Clinical efficacy of dim light melatonin onset testing in diagnosing delayed sleep phase syndrome.

PubMed

Rahman, Shadab A; Kayumov, Leonid; Tchmoutina, Ekaterina A; Shapiro, Colin M

2009-05-01

Delayed Sleep Phase Syndrome (DSPS) arises from biological clock desynchrony and accounts for 10% of chronic insomnia patients. Currently DSPS is diagnosed based on sleep/wake cycle disruptions rather than examining the underlying biological clock alterations. The objective of the study was to determine the sensitivity and specificity of the Dim Light Melatonin Onset (DLMO) Test in diagnosing DSPS in a clinical setting. Fifty-six patients (mean age 28 years) symptomatic of DSPS participated in the study. Following an initial assessment of DSPS using sleep diaries, participants underwent two consecutive nights of polysomnography (PSG), with an imposed sleep period on the second night to demonstrate the delay in the timing of habitual sleep period and to thereby confirm DSPS. Circadian phase delays were also measured using melatonin secretion profiles, and the efficacy of diagnosing DSPS using DLMO was compared to using sleep diaries and PSG. Melatonin secretion was assayed for each individual by ELISA using saliva samples. Main outcome measures included the time of melatonin secretion onset, clinical sensitivity and specificity of the DLMO test. The time of melatonin secretion onset was significantly delayed in DSPS patients. Clinical sensitivity and specificity of the DLMO test in diagnosing DSPS were 90.3% and 84.0%, respectively. The DLMO test is an accurate tool for differentiating between sleep disorder patients with or without underlying circadian rhythm disruption. It is effective for phase typing DSPS patients in a clinical setting.

Dual conception of risk in the Iowa Gambling Task: effects of sleep deprivation and test-retest gap.

PubMed

Singh, Varsha

2013-01-01

Risk in the Iowa Gambling Task (IGT) is often understood in terms of intertemporal choices, i.e., preference for immediate outcomes in favor of delayed outcomes is considered risky decision making. According to behavioral economics, healthy decision makers are expected to refrain from choosing the short-sighted immediate gain because, over time (10 trials of the IGT), the immediate gains result in a long term loss (net loss). Instead decision makers are expected to maximize their gains by choosing options that, over time (10 trials), result in delayed or long term gains (net gain). However, task choices are sometimes made on the basis of the frequency of reward and punishment such that frequent rewards/infrequent punishments are favored over infrequent rewards/frequent punishments. The presence of these two attributes (intertemporality and frequency of reward) in IGT decision making may correspond to the emotion-cognition dichotomy and reflect a dual conception of risk. Decision making on the basis of the two attributes was tested under two conditions: delay in retest and sleep deprivation. An interaction between sleep deprivation and time delay was expected to attenuate the difference between the two attributes. Participants were 40 male university students. Analysis of the effects of IGT attribute type (intertemporal vs. frequency of reinforcement), sleep deprivation (sleep deprivation vs. no sleep deprivation), and test-retest gap (short vs. long delay) showed a significant within-subjects effect of IGT attribute type thus confirming the difference between the two attributes. Sleep deprivation had no effect on the attributes, but test-retest gap and the three-way interaction between attribute type, test-retest gap, and sleep deprivation were significantly different. Post-hoc tests revealed that sleep deprivation and short test-retest gap attenuated the difference between the two attributes. Furthermore, the results showed an expected trend of increase in intertemporal decision making at retest suggesting that intertemporal decision making benefited from repeated task exposure. The present findings add to understanding of the emotion-cognition dichotomy. Further, they show an important time-dependent effect of a universally experienced constraint (sleep deprivation) on decision making. It is concluded that risky decision making in the IGT is contingent on the attribute under consideration and is affected by factors such as time elapsed and constraint experienced before the retest.

Acute versus chronic partial sleep deprivation in middle-aged people: differential effect on performance and sleepiness.

PubMed

Philip, Pierre; Sagaspe, Patricia; Prague, Mélanie; Tassi, Patricia; Capelli, Aurore; Bioulac, Bernard; Commenges, Daniel; Taillard, Jacques

2012-07-01

To evaluate the effects of acute sleep deprivation and chronic sleep restriction on vigilance, performance, and self-perception of sleepiness. Habitual night followed by 1 night of total sleep loss (acute sleep deprivation) or 5 consecutive nights of 4 hr of sleep (chronic sleep restriction) and recovery night. Eighteen healthy middle-aged male participants (age [(± standard deviation] = 49.7 ± 2.6 yr, range 46-55 yr). Multiple sleep latency test trials, Karolinska Sleepiness Scale scores, simple reaction time test (lapses and 10% fastest reaction times), and nocturnal polysomnography data were recorded. Objective and subjective sleepiness increased immediately in response to sleep restriction. Sleep latencies after the second and third nights of sleep restriction reached levels equivalent to those observed after acute sleep deprivation, whereas Karolinska Sleepiness Scale scores did not reach these levels. Lapse occurrence increased after the second day of sleep restriction and reached levels equivalent to those observed after acute sleep deprivation. A statistical model revealed that sleepiness and lapses did not progressively worsen across days of sleep restriction. Ten percent fastest reaction times (i.e., optimal alertness) were not affected by acute or chronic sleep deprivation. Recovery to baseline levels of alertness and performance occurred after 8-hr recovery night. In middle-aged study participants, sleep restriction induced a high increase in sleep propensity but adaptation to chronic sleep restriction occurred beyond day 3 of restriction. This sleepiness attenuation was underestimated by the participants. One recovery night restores daytime sleepiness and cognitive performance deficits induced by acute or chronic sleep deprivation. Philip P; Sagaspe P; Prague M; Tassi P; Capelli A; Bioulac B; Commenges D; Taillard J. Acute versus chronic partial sleep deprivation in middle-aged people: differential effect on performance and sleepiness. SLEEP 2012;35(7):997-1002.

Sleep restriction and degraded reaction-time performance in Figaro solo sailing races.

PubMed

Hurdiel, Rémy; Van Dongen, Hans P A; Aron, Christophe; McCauley, Peter; Jacolot, Laure; Theunynck, Denis

2014-01-01

In solo offshore sailing races like those of the Solitaire du Figaro, sleep must be obtained in multiple short bouts to maintain competitive performance and safety. Little is known about the amount of sleep restriction experienced at sea and the effects that fatigue from sleep loss have on sailors' performance. Therefore, we assessed sleep in sailors of yachts in the Figaro 2 Beneteau class during races and compared response times on a serial simple reaction-time test before and after races. Twelve men (professional sailors) recorded their sleep and measured their response times during one of the three single-handed races of 150, 300 and 350 nautical miles (nominally 24-50 h in duration). Total estimated sleep duration at sea indicated considerable sleep insufficiency. Response times were slower after races than before. The results suggest that professional sailors incur severe sleep loss and demonstrate marked performance impairment when competing in one- to two-day solo sailing races. Competitive performance could be improved by actively managing sleep during solo offshore sailing races.

Narcolepsy with Long Sleep Time: A Specific Entity?

PubMed Central

Vernet, Cyrille; Arnulf, Isabelle

2009-01-01

Background: The classical narcolepsy patient reports intense feelings of sleepiness (with/out cataplexy), normal or disrupted nighttime sleep, and takes short and restorative naps. However, with long-term monitoring, we identified some narcoleptics resembling patients with idiopathic hypersomnia. Objective: To isolate and describe a new subtype of narcolepsy with long sleep time). Setting: University Hospital Design: Controlled, prospective cohort Participants: Out of 160 narcoleptics newly diagnosed within the past 3 years, 29 (18%) had a long sleep time (more than 11 h/24 h). We compared narcoleptics with (n = 23) and without (n = 29) long sleep time to 25 hypersomniacs with long sleep time and 20 healthy subjects. Intervention: Patients and controls underwent face-to face interviews, questionnaires, human leukocyte antigen (HLA) genotype, an overnight polysomnography, multiple sleep latency tests, and 24-h ad libitum sleep monitoring. Results: Narcoleptics with long sleep time had a similar disease course and similar frequencies of cataplexy, sleep paralysis, hallucinations, multiple sleep onset in REM periods, short mean sleep latencies, and HLA DQB1*0602 positivity as narcoleptics with normal sleep time did. However, they had longer sleep time during 24 h, and higher sleep efficiency, lower Epworth Sleepiness Scale scores, and reported their naps were more often unrefreshing. Only 3/23 had core narcolepsy (HLA and cataplexy positive). Conclusions: The subgroup of narcoleptics with a long sleep time comprises 18% of narcoleptics. Their symptoms combine the disabilities of both narcolepsy (severe sleepiness) and idiopathic hypersomnia (long sleep time and unrefreshing naps). Thus, they may constitute a group with multiple arousal system dysfunctions. Citation: Vernet C; Arnulf I. Narcolepsy with long sleep time: a specific entity? SLEEP 2009;32(9):1229-1235. PMID:19750928

The Effects of Sleep on Emotional Target Detection Performance: A Novel iPad-Based Pediatric Game

PubMed Central

Colonna, Annalisa; Smith, Anna B.; Smith, Stuart; VanDenEshof, Kirandeep; Orgill, Jane; Gringras, Paul; Pal, Deb K.

2018-01-01

Background: Consolidation of learning occurs during sleep but when it is disturbed there may be an adverse impact upon these functions. While research has focused upon how sleep affects cognition in adulthood, the effects of disrupted sleep are likely to impact more heavily on learning among children and adolescents. We aimed to investigate whether a night’s sleep impacts upon executive function compared with an equivalent wakefulness period. We also wanted to know whether restricting sleep would reduce these effects on performance. To investigate this issue in children, we adapted existing research methods to make them more suitable for this population. Methods: Using a cross-over trial design, 22 children aged 7–14 completed an updated but previously validated, continuous performance task (CPT) designed to be appealing to children, containing emotional and neutral targets and presented on an iPad. We measured omission and commission errors, mean and variability of reaction times (RTs) immediately and after a delay spent in the following three ways: 11-h intervals of unrestricted and restricted sleep in the style of a ‘sleepover’ and daytime wakefulness. We examined differences in immediate and delayed testing for each dependent variable. Both sleep nights were spent in a specialist sleep lab where polysomnography data were recorded. Results: While there were no significant main effects of sleep condition, as expected we observed significantly faster and more accurate performance in delayed compared with immediate testing across all conditions for omission errors, RT and variability of RT. Importantly, we saw a significant interaction for commission errors to emotional targets (p = 0.034): while they were comparable across all conditions during immediate testing, for delayed testing there were significantly more errors after wakefulness compared with unrestricted sleep (p = 0.019) and at a trend level for restricted sleep (p = 0.063). Performance improvement after restricted sleep was inversely correlated with sleep opportunity time (p = 0.03), total sleep time (p = 0.01) and total non-REM time (p = 0.005). Conclusion: This tool, designed to be simple to use and appealing to children, revealed a preserving effect of typical and disrupted sleep periods on performance during an emotionally themed target detection task compared with an equivalent wakefulness period. PMID:29563887

How Many Sleep Diary Entries Are Needed to Reliably Estimate Adolescent Sleep?

PubMed

Short, Michelle A; Arora, Teresa; Gradisar, Michael; Taheri, Shahrad; Carskadon, Mary A

2017-03-01

To investigate (1) how many nights of sleep diary entries are required for reliable estimates of five sleep-related outcomes (bedtime, wake time, sleep onset latency [SOL], sleep duration, and wake after sleep onset [WASO]) and (2) the test-retest reliability of sleep diary estimates of school night sleep across 12 weeks. Data were drawn from four adolescent samples (Australia [n = 385], Qatar [n = 245], United Kingdom [n = 770], and United States [n = 366]), who provided 1766 eligible sleep diary weeks for reliability analyses. We performed reliability analyses for each cohort using complete data (7 days), one to five school nights, and one to two weekend nights. We also performed test-retest reliability analyses on 12-week sleep diary data available from a subgroup of 55 US adolescents. Intraclass correlation coefficients for bedtime, SOL, and sleep duration indicated good-to-excellent reliability from five weekday nights of sleep diary entries across all adolescent cohorts. Four school nights was sufficient for wake times in the Australian and UK samples, but not the US or Qatari samples. Only Australian adolescents showed good reliability for two weekend nights of bedtime reports; estimates of SOL were adequate for UK adolescents based on two weekend nights. WASO was not reliably estimated using 1 week of sleep diaries. We observed excellent test-rest reliability across 12 weeks of sleep diary data in a subsample of US adolescents. We recommend at least five weekday nights of sleep dairy entries to be made when studying adolescent bedtimes, SOL, and sleep duration. Adolescent sleep patterns were stable across 12 consecutive school weeks. © Sleep Research Society 2017. Published by Oxford University Press on behalf of the Sleep Research Society. All rights reserved. For permissions, please e-mail journals.permissions@oup.com.

Sleep-disordered breathing: a survey of otolaryngologic practice at military hospitals.

PubMed

Davidson, T M; Do, K L

2000-11-01

We conducted a survey of otolaryngologists at all Veterans Administration and Department of Defense hospitals in the United States to ascertain the nature and scope of their treatment of sleep-disordered breathing. Questionnaire responses indicated that head and neck surgeons in military hospitals have a strong interest in the management of patients with snoring and sleep apnea. Because of the difficulty in obtaining timely sleep test results and the low number of referrals from physicians who perform such testing, many otolaryngologists expressed a desire to be able to perform their own sleep testing.

The biologic effects of grounding the human body during sleep as measured by cortisol levels and subjective reporting of sleep, pain, and stress.

PubMed

Ghaly, Maurice; Teplitz, Dale

2004-10-01

Diurnal cortisol secretion levels were measured and circadian cortisol profiles were evaluated in a pilot study conducted to test the hypothesis that grounding the human body to earth during sleep will result in quantifiable changes in cortisol. It was also hypothesized that grounding the human body would result in changes in sleep, pain, and stress (anxiety, depression, irritability), as measured by subjective reporting. Twelve (12) subjects with complaints of sleep dysfunction, pain, and stress were grounded to earth during sleep for 8 weeks in their own beds using a conductive mattress pad. Saliva tests were administered to establish pregrounding baseline cortisol levels. Levels were obtained at 4-hour intervals for a 24-hour period to determine the circadian cortisol profile. Cortisol testing was repeated at week 6. Subjective symptoms of sleep dysfunction, pain, and stress were reported daily throughout the 8-week test period. Measurable improvements in diurnal cortisol profiles were observed, with cortisol levels significantly reduced during night-time sleep. Subjects' 24-hour circadian cortisol profiles showed a trend toward normalization. Subjectively reported symptoms, including sleep dysfunction, pain, and stress, were reduced or eliminated in nearly all subjects. Results indicate that grounding the human body to earth ("earthing") during sleep reduces night-time levels of cortisol and resynchronizes cortisol hormone secretion more in alignment with the natural 24-hour circadian rhythm profile. Changes were most apparent in females. Furthermore, subjective reporting indicates that grounding the human body to earth during sleep improves sleep and reduces pain and stress.

Is sleep-related verbal memory consolidation impaired in sleepwalkers?

PubMed

Uguccioni, Ginevra; Pallanca, Olivier; Golmard, Jean-Louis; Leu-Semenescu, Smaranda; Arnulf, Isabelle

2015-04-01

In order to evaluate verbal memory consolidation during sleep in subjects experiencing sleepwalking or sleep terror, 19 patients experiencing sleepwalking/sleep terror and 19 controls performed two verbal memory tasks (16-word list from the Free and Cued Selective Reminding Test, and a 220- and 263-word modified story recall test) in the evening, followed by nocturnal video polysomnography (n = 29) and morning recall (night-time consolidation after 14 h, n = 38). The following morning, they were given a daytime learning task using the modified story recall test in reverse order, followed by an evening recall test after 9 h of wakefulness (daytime consolidation, n = 38). The patients experiencing sleepwalking/sleep terror exhibited more frequent awakenings during slow-wave sleep and longer wakefulness after sleep onset than the controls. Despite this reduction in sleep quality among sleepwalking/sleep terror patients, they improved their scores on the verbal tests the morning after sleep compared with the previous evening (+16 ± 33%) equally well as the controls (+2 ± 13%). The performance of both groups worsened during the daytime in the absence of sleep (-16 ± 15% for the sleepwalking/sleep terror group and -14 ± 11% for the control group). There was no significant correlation between the rate of memory consolidation and any of the sleep measures. Seven patients experiencing sleepwalking also sleep-talked during slow-wave sleep, but their sentences were unrelated to the tests or the list of words learned during the evening. In conclusion, the alteration of slow-wave sleep during sleepwalking/sleep terror does not noticeably impact on sleep-related verbal memory consolidation. © 2014 European Sleep Research Society.

Longitudinal associations between time spent using technology and sleep duration among adolescents.

PubMed

Mazzer, K; Bauducco, S; Linton, S J; Boersma, K

2018-07-01

Technology use has been the focus of much concern for adolescents' sleep health. However, few studies have investigated the bidirectional association between sleep duration and time spent using technology. The aim of this study was to test whether time spent using technology predicted shorter sleep duration, and/or vice versa using cross-lagged analyses over one year. Participants were 1620 high school students in the 8th and 9th grade at baseline from 17 public schools in three middle Sweden communities. Students completed questionnaires at school during the spring of 2015 and 2016. Time spent using technology was self-reported and sleep duration was calculated from reported bed-times, wake-times and sleep onset latency. Time spent using technology significantly predicted shorter subsequent sleep duration and vice versa. Public health advocates educating others about the negative impacts of technology on sleep must also be mindful of the opposite, that many young people may turn to technological devices when experiencing difficulty sleeping. Copyright © 2018 The Foundation for Professionals in Services for Adolescents. Published by Elsevier Ltd. All rights reserved.

Sleep Management Strategy and Performance in an Extreme Mountain Ultra-marathon.

PubMed

Poussel, Mathias; Laroppe, Julien; Hurdiel, Rémy; Girard, Julien; Poletti, Laurence; Thil, Catherine; Didelot, Antoine; Chenuel, Bruno

2015-01-01

We intended to assess the relationship between sleep strategies and performance during the North-Face Ultra-Trail du Mont-Blanc 2013, to test the hypothesis that sleep management can influence athletic performance. Almost all runners specifically adopted sleep management strategies before the race. Among the finishers 72% didn't sleep at all during the race and 28% took a least one break for sleep. Non-sleepers completed the race faster than the sleepers (P = 0.0008). Race time was positively correlated with drowsiness (P < 0.0001) and negatively correlated with the number participations in this race (P = 0.0039). Runners who adopted a sleep management strategy based on increased sleep time before the race completed the race faster (P = 0.0258). Most finishers seemed to be aware of the importance of developing sleep management strategies and increasing sleep time some nights before the race appeared to be the most relevant strategy to improve performance.

Teacher’s sleep quality: linked to social job characteristics?

PubMed Central

KOTTWITZ, Maria U.; GERHARDT, Christin; PEREIRA, Diana; ISELI, Lionel; ELFERING, Achim

2017-01-01

Besides dealing with high workload, being a teacher is challenging with respect to the social context. There is increasing evidence that adverse social job characteristics challenge sleep quality. The current study tests whether restraint sleep quality (defined as worse sleep quality before than during vacation) is related to time-related job stressors, job resources, and social job characteristics. Forty-eight elementary school teachers (42% women) participated both during the last week before and the first week after vacation. Before vacation, teachers were asked for demographics and working conditions with reference to the last 30 d, and sleep quality with reference to the last 7 d. After vacation sleep quality during vacation was assessed and used as reference for working time sleep quality. Results showed mean levels of sleep quality increased during vacation. In teachers with restrained working time sleep quality (38%), experiences of failure at work, social exclusion, and emotional dissonance were more frequent than in teachers with unrestrained working time sleep quality (Ps<0.05). Groups did not differ in time-related stressors, time control and social support from supervisors. Emotion work, social exclusion and individual experience of failure seem to challenge sleep quality in teachers. PMID:28804097

Teacher's sleep quality: linked to social job characteristics?

PubMed

Kottwitz, Maria U; Gerhardt, Christin; Pereira, Diana; Iseli, Lionel; Elfering, Achim

2018-02-07

Besides dealing with high workload, being a teacher is challenging with respect to the social context. There is increasing evidence that adverse social job characteristics challenge sleep quality. The current study tests whether restraint sleep quality (defined as worse sleep quality before than during vacation) is related to time-related job stressors, job resources, and social job characteristics. Forty-eight elementary school teachers (42% women) participated both during the last week before and the first week after vacation. Before vacation, teachers were asked for demographics and working conditions with reference to the last 30 d, and sleep quality with reference to the last 7 d. After vacation sleep quality during vacation was assessed and used as reference for working time sleep quality. Results showed mean levels of sleep quality increased during vacation. In teachers with restrained working time sleep quality (38%), experiences of failure at work, social exclusion, and emotional dissonance were more frequent than in teachers with unrestrained working time sleep quality (Ps<0.05). Groups did not differ in time-related stressors, time control and social support from supervisors. Emotion work, social exclusion and individual experience of failure seem to challenge sleep quality in teachers.

Effect of carbon monoxide exposure on human sleep and psychomotor performance

DOE Office of Scientific and Technical Information (OSTI.GOV)

O'Donnell, R.D.; Chikos, P.; Theodore, J.

1971-01-01

Four volunteers exposed for 9 hr (11 p.m. to 8 a.m.) to 75 or 150 ppM CO had COHb concentrations of 5.9 and 12.7%, respectively. Sleep habits and subsequent performance were measured. CO induced slight changes in sleeping habits including more deep sleep at expense of light sleep (especially at beginning of exposure) and a reduction in number of sleep stage changes. However, REM sleep was not affected. No effect of CO on complex cognitive or psychromotor activity measured by mental arithmetic, time estimation, tracking and monitoring under moderate or heavy stress, tone-time difference estimation, and critical flicker fusion tests.

The Effects of Sleep Deprivation on Soccer Skills.

PubMed

Pallesen, Ståle; Gundersen, Hilde Stokvold; Kristoffersen, Morten; Bjorvatn, Bjørn; Thun, Eirunn; Harris, Anette

2017-08-01

Many athletes sleep poorly due to stress, travel, and competition anxiety. In the present study, we investigated the effects of sleep deprivation on soccer skills (juggling, dribbling, ball control, continuous kicking, 20 and 40 m sprint, and 30 m sprint with changes of direction). In all, 19 male junior soccer players (14-19 years old) were recruited and participated in a cross-balanced experimental study comprising two conditions; habitual sleep and 24 hours sleep deprivation. In both conditions, testing took place between 8 a.m. and 10 a.m. Order of tests was counterbalanced. Each test was conducted once or twice in a sequence repeated three times. The results revealed a negative effect of sleep deprivation on the continuous kicking test. On one test, 30 meter sprint with directional changes, a significant condition × test repetition interaction was found, indicating a steeper learning curve in the sleep deprived condition from Test 1 to Test 2 and a steeper learning curve in the rested condition from Test 2 to Test 3. The results are discussed in terms of limitations and strengths, and recommendations for future studies are outlined.

Short-term total sleep deprivation alters delay-conditioned memory in the rat.

PubMed

Tripathi, Shweta; Jha, Sushil K

2016-06-01

Short-term sleep deprivation soon after training may impair memory consolidation. Also, a particular sleep stage or its components increase after learning some tasks, such as negative and positive reinforcement tasks, avoidance tasks, and spatial learning tasks, and so forth. It suggests that discrete memory types may require specific sleep stage or its components for their optimal processing. The classical conditioning paradigms are widely used to study learning and memory but the role of sleep in a complex conditioned learning is unclear. Here, we have investigated the effects of short-term sleep deprivation on the consolidation of delay-conditioned memory and the changes in sleep architecture after conditioning. Rats were trained for the delay-conditioned task (for conditioning, house-light [conditioned stimulus] was paired with fruit juice [unconditioned stimulus]). Animals were divided into 3 groups: (a) sleep deprived (SD); (b) nonsleep deprived (NSD); and (c) stress control (SC) groups. Two-way ANOVA revealed a significant interaction between groups and days (training and testing) during the conditioned stimulus-unconditioned stimulus presentation. Further, Tukey post hoc comparison revealed that the NSD and SC animals exhibited significant increase in performances during testing. The SD animals, however, performed significantly less during testing. Further, we observed that wakefulness and NREM sleep did not change after training and testing. Interestingly, REM sleep increased significantly on both days compared to baseline more specifically during the initial 4-hr time window after conditioning. Our results suggest that the consolidation of delay-conditioned memory is sleep-dependent and requires augmented REM sleep during an explicit time window soon after training. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

Acute Versus Chronic Partial Sleep Deprivation in Middle-Aged People: Differential Effect on Performance and Sleepiness

PubMed Central

Philip, Pierre; Sagaspe, Patricia; Prague, Mélanie; Tassi, Patricia; Capelli, Aurore; Bioulac, Bernard; Commenges, Daniel; Taillard, Jacques

2012-01-01

Study Objective: To evaluate the effects of acute sleep deprivation and chronic sleep restriction on vigilance, performance, and self-perception of sleepiness. Design: Habitual night followed by 1 night of total sleep loss (acute sleep deprivation) or 5 consecutive nights of 4 hr of sleep (chronic sleep restriction) and recovery night. Participants: Eighteen healthy middle-aged male participants (age [(± standard deviation] = 49.7 ± 2.6 yr, range 46-55 yr). Measurements: Multiple sleep latency test trials, Karolinska Sleepiness Scale scores, simple reaction time test (lapses and 10% fastest reaction times), and nocturnal polysomnography data were recorded. Results: Objective and subjective sleepiness increased immediately in response to sleep restriction. Sleep latencies after the second and third nights of sleep restriction reached levels equivalent to those observed after acute sleep deprivation, whereas Karolinska Sleepiness Scale scores did not reach these levels. Lapse occurrence increased after the second day of sleep restriction and reached levels equivalent to those observed after acute sleep deprivation. A statistical model revealed that sleepiness and lapses did not progressively worsen across days of sleep restriction. Ten percent fastest reaction times (i.e., optimal alertness) were not affected by acute or chronic sleep deprivation. Recovery to baseline levels of alertness and performance occurred after 8-hr recovery night. Conclusions: In middle-aged study participants, sleep restriction induced a high increase in sleep propensity but adaptation to chronic sleep restriction occurred beyond day 3 of restriction. This sleepiness attenuation was underestimated by the participants. One recovery night restores daytime sleepiness and cognitive performance deficits induced by acute or chronic sleep deprivation. Citation: Philip P; Sagaspe P; Prague M; Tassi P; Capelli A; Bioulac B; Commenges D; Taillard J. Acute versus chronic partial sleep deprivation in middle-aged people: differential effect on performance and sleepiness. SLEEP 2012;35(7):997–1002. PMID:22754046

Idiopathic hypersomnia with and without long sleep time: a controlled series of 75 patients.

PubMed

Vernet, Cyrille; Arnulf, Isabelle

2009-06-01

To characterize the clinical, psychological, and sleep pattern of idiopathic hypersomnia with and without long sleep time, and provide normative values for 24-hour polysomnography. University Hospital. Controlled, prospective cohort. 75 consecutive patients (aged 34 +/- 12 y) with idiopathic hypersomnia and 30 healthy matched controls. Patients and controls underwent during 48 hours a face-to-face interview, questionnaires, human leukocyte antigen genotype, a night polysomnography and multiple sleep latency test (MSLT), followed by 24-h ad libitum sleep monitoring. Hypersomniacs had more fatigue, higher anxiety and depression scores, and more frequent hypnagogic hallucinations (24%), sleep paralysis (28%), sleep drunkenness (36%), and unrefreshing naps (46%) than controls. They were more frequently evening types. DQB1*0602 genotype was similarly found in hypersomniacs (24.2%) and controls (19.2%). Hypersomniacs had more frequent slow wave sleep after 06:00 than controls. During 24-h polysomnography, the 95% confidence interval for total sleep time was 493-558 min in controls, versus 672-718 min in hypersomniacs. There were 40 hypersomniacs with and 35 hypersomniacs without long ( > 600 min) sleep time. The hypersomniacs with long sleep time were younger (29 +/- 10 vs 40 +/- 13 y, P = 0.0002), slimmer (body mass index: 26 +/- 5 vs 23 +/- 4 kg/m2; P = 0.005), and had lower Horne-Ostberg scores and higher sleep efficiencies than those without long sleep time. MSLT latencies were normal (> 8 min) in 71% hypersomniacs with long sleep time. Hypersomnia, especially with long sleep time, is frequently associated with evening chronotype and young age. It is inadequately diagnosed using MSLT.

Sleep Characteristics and Carotid Atherosclerosis Among Midlife Women.

PubMed

Thurston, Rebecca C; Chang, Yuefang; von Känel, Roland; Barinas-Mitchell, Emma; Jennings, J Richard; Hall, Martica H; Santoro, Nanette; Buysse, Daniel J; Matthews, Karen A

2017-02-01

Midlife, which encompasses the menopause transition in women, can be a time of disrupted sleep and accelerated atherosclerosis accumulation. Short or poor sleep quality has been associated with cardiovascular disease (CVD) risk; few studies have investigated relations among midlife women. We tested whether shorter actigraphy sleep time or poorer subjective sleep quality was associated with carotid atherosclerosis among midlife women. Two hundred fifty-six peri- and postmenopausal women aged 40-60 years completed 3 days of wrist actigraphy, hot flash monitoring, questionnaires (Pittsburgh Sleep Quality Index [PSQI], Berlin), a blood draw, and carotid ultrasound [intima media thickness (IMT), plaque]. Associations of objective (actigraphy) and subjective (PSQI) sleep with IMT/plaque were tested in regression models (covariates: age, race, education, body mass index, blood pressure, lipids, insulin resistance, medications, snoring, depressive symptoms, sleep hot flashes, and estradiol). Shorter objective sleep time was associated with higher odds of carotid plaque (for each hour shorter sleep, plaque score ≥ 2, odds ratio (OR) [95% confidence interval, CI] = 1.58 [1.11-2.27], p = .01; plaque score = 1, OR [95% CI] = 0.95 [0.68-1.32], p = .75, vs. no plaque, multivariable). Poorer subjective sleep quality was associated with higher mean IMT [β, b (standard error, SE) = 0.004 (0.002), p = .03], maximal IMT [b (SE) = 0.009 (0.003), p = .005], and plaque [plaque score ≥ 2, OR (95% CI) = 1.23 (1.09-1.40), p = .001; score = 1, OR (95% CI) = 1.06 (0.93-1.21), p = .37, vs. no plaque] in multivariable models. Findings persisted additionally adjusting for sleep hot flashes and estradiol. Shorter actigraphy-assessed sleep time and poorer subjective sleep quality were associated with increased carotid atherosclerosis among midlife women. Associations persisted adjusting for CVD risk factors, hot flashes, and estradiol. © Sleep Research Society 2016. Published by Oxford University Press on behalf of the Sleep Research Society. All rights reserved. For permissions, please e-mail journals.permissions@oup.com.

Getting a Good Night's Sleep in Adolescence: Do Strategies for Coping With Stress Matter?

PubMed

Matthews, Karen A; Hall, Martica H; Cousins, Jennifer; Lee, Laisze

2016-01-01

Getting a good night's sleep is challenging for adolescents because of early school start times and adolescents' substantial social and physical changes. We tested whether key indices of sleep health are associated with usual styles of coping with stress and interpersonal conflict in healthy black and white adolescents. Two hundred forty-two (57% female, 56% black) high school students completed daily sleep diaries, questionnaires, and actigraphy across a school week. Linear regression models tested associations, independent of race, gender, and other covariates. Students who reported using disengagement coping exhibited poor sleep health. They had shorter sleep duration, more fragmented sleep, delayed sleep, and increased daytime sleepiness. Unexpectedly, positive engagement coping was related to daytime sleepiness and delayed sleep, although not in models that included disengagement coping. Coping strategies may be an important influence on adolescent sleep. Future research should evaluate the antecedent-consequent relationships among coping, sleep, and stress.

Effects of Acute Sleep Deprivation Resulting from Night Shift Work on Young Doctors.

PubMed

Sanches, Inês; Teixeira, Fátima; dos Santos, José Moutinho; Ferreira, António Jorge

2015-01-01

To evaluate sleep deprivation and its effects on young physicians in relation to concentration capacity and psychomotor performance. Eighteen physicians aged 26 - 33 years were divided into 2 groups: non-sleep deprived group (with no night work) and sleep deprived group (minimum 12 hour of night work/week). We applied Pittsburgh Sleep Quality Index to screen the presence of sleep pathology and Epworth Sleepiness Scale to evaluate subjective daytime sleepiness; we used actigraphy and sleep diary to assess sleep hygiene and standard sleep-wake cycles. To demonstrate the effects of sleep deprivation, we applied Toulouse-Piéron's test (concentration test) and a battery of three reaction time tasks after the night duty. Sleep deprived group had higher daytime sleepiness on Epworth Sleepiness Scale (p < 0.05) and during week sleep deprivation was higher (p < 0.010). The mean duration of sleep during the period of night duty was 184.2 minutes to sleep deprived group and 397.7 minutes to non-sleep deprived group (p < 0.001). In the Toulouse-Piéron's test, the sleep deprived group had more omissions (p < 0.05) with a poorer result in concentration (p < 0.05). Psychomotor tests that evaluated response to simple stimuli revealed longer response latency (p < 0.05) and more errors (p < 0.05) in Sleep deprived group; in reaction to instruction test the sleep deprived group showed worse perfection index (p < 0.05); in the fine movements test there was no statistically significant difference between the groups. Acute sleep deprivation resulting from nocturnal work in medical professions is associated with a reduction in attention and concentration and delayed response to stimuli. This may compromise patient care as well as the physician's health and quality of life. It is essential to study the effects of acute sleep deprivation on the cognitive abilities and performance of health professionals.

Sleep inertia during a simulated 6-h on/6-h off fixed split duty schedule.

PubMed

Hilditch, Cassie J; Short, Michelle; Van Dongen, Hans P A; Centofanti, Stephanie A; Dorrian, Jillian; Kohler, Mark; Banks, Siobhan

Sleep inertia is a safety concern for shift workers returning to work soon after waking up. Split duty schedules offer an alternative to longer shift periods, but introduce additional wake-ups and may therefore increase risk of sleep inertia. This study investigated sleep inertia across a split duty schedule. Sixteen participants (age range 21-36 years; 10 females) participated in a 9-day laboratory study with two baseline nights (10 h time in bed, [TIB]), four 24-h periods of a 6-h on/6-h off split duty schedule (5-h TIB in off period; 10-h TIB per 24 h) and two recovery nights. Two complementary rosters were evaluated, with the timing of sleep and wake alternating between the two rosters (2 am/2 pm wake-up roster versus 8 am/8 pm wake-up roster). At 2, 17, 32 and 47 min after scheduled awakening, participants completed an 8-min inertia test bout, which included a 3-min psychomotor vigilance test (PVT-B), a 3-min Digit-Symbol Substitution Task (DSST), the Karolinska Sleepiness Scale (KSS), and the Samn-Perelli Fatigue Scale (SP-Fatigue). Further testing occurred every 2 h during scheduled wakefulness. Performance was consistently degraded and subjective sleepiness/fatigue was consistently increased during the inertia testing period as compared to other testing times. Morning wake-ups (2 am and 8 am) were associated with higher levels of sleep inertia than later wake-ups (2 pm and 8 pm). These results suggest that split duty workers should recognise the potential for sleep inertia after waking, especially during the morning hours.

Daily antecedents and consequences of nightly sleep.

PubMed

Lee, Soomi; Crain, Tori L; McHale, Susan M; Almeida, David M; Buxton, Orfeu M

2017-08-01

Sleep can serve as both cause and consequence of individuals' everyday experiences. We built upon prior studies of the correlates of sleep, which have relied primarily on cross-sectional data, to examine the antecedents and consequences of sleep using a daily diary design. Specifically, we assessed the temporal sequence between nightly sleep and daily psychosocial stressors. Parents employed in a US information technology company (n = 102) completed eight consecutive daily diaries at both baseline and 1 year later. In telephone interviews each evening, participants reported on the previous night's sleep hours, sleep quality and sleep latency. They also reported daily work-to-family conflict and time inadequacy (i.e. perceptions of not having enough time) for their child and for themselves to engage in exercise. Multi-level models testing lagged and non-lagged effects simultaneously revealed that sleep hours and sleep quality were associated with next-day consequences of work-to-family conflict and time inadequacy, whereas psychosocial stressors as antecedents did not predict sleep hours or quality that night. For sleep latency, the opposite temporal order emerged: on days with more work-to-family conflict or time inadequacy for child and self than usual, participants reported longer sleep latencies than usual. An exception to this otherwise consistent pattern was that time inadequacy for child also preceded shorter sleep hours and poorer sleep quality that night. The results highlight the utility of a daily diary design for capturing the temporal sequences linking sleep and psychosocial stressors. © 2016 European Sleep Research Society.

Estimating sleep parameters using nasal pressure signals applicable to continuous positive airway pressure devices.

PubMed

Park, Jong-Uk; Erdenebayar, Urtnasan; Joo, Eun-Yeon; Lee, Kyoung-Joung

2017-06-27

This paper proposes a method for classifying sleep-wakefulness and estimating sleep parameters using nasal pressure signals applicable to a continuous positive airway pressure (CPAP) device. In order to classify the sleep-wakefulness states of patients with sleep-disordered breathing (SDB), apnea-hypopnea and snoring events are first detected. Epochs detected as SDB are classified as sleep, and time-domain- and frequency-domain-based features are extracted from the epochs that are detected as normal breathing. Subsequently, sleep-wakefulness is classified using a support vector machine (SVM) classifier in the normal breathing epoch. Finally, four sleep parameters-sleep onset, wake after sleep onset, total sleep time and sleep efficiency-are estimated based on the classified sleep-wakefulness. In order to develop and test the algorithm, 110 patients diagnosed with SDB participated in this study. Ninety of the subjects underwent full-night polysomnography (PSG) and twenty underwent split-night PSG. The subjects were divided into 50 patients of a training set (full/split: 42/8), 30 of a validation set (full/split: 24/6) and 30 of a test set (full/split: 24/6). In the experiments conducted, sleep-wakefulness classification accuracy was found to be 83.2% in the test set, compared with the PSG scoring results of clinical experts. Furthermore, all four sleep parameters showed higher correlations than the results obtained via PSG (r  ⩾  0.84, p  <  0.05). In order to determine whether the proposed method is applicable to CPAP, sleep-wakefulness classification performances were evaluated for each CPAP in the split-night PSG data. The results indicate that the accuracy and sensitivity of sleep-wakefulness classification by CPAP variation shows no statistically significant difference (p  <  0.05). The contributions made in this study are applicable to the automatic classification of sleep-wakefulness states in CPAP devices and evaluation of the quality of sleep.

The Effects of Sleep Restriction and Extension on School-Age Children: What a Difference an Hour Makes.

ERIC Educational Resources Information Center

Sadeh, Avi; Gruber, Reut; Raviv, Amiram

2003-01-01

Assessed effects of sleep restriction and extension on 9- to 12-year-olds' neurobehavioral functioning. Found that modest sleep restriction led to improved sleep quality but to reduced reported alertness. Children who extended sleep improved significantly from baseline their performance on the digit forward memory test and reaction time on the…

Restricting Time in Bed in Early Adolescence Reduces Both NREM and REM Sleep but Does Not Increase Slow Wave EEG

PubMed Central

Campbell, Ian G.; Kraus, Amanda M.; Burright, Christopher S.; Feinberg, Irwin

2016-01-01

Study Objectives: School night total sleep time decreases across adolescence (9–18 years) by 10 min/year. This decline is comprised entirely of a selective decrease in NREM sleep; REM sleep actually increases slightly. Decreasing sleep duration across adolescence is often attributed to insufficient time in bed. Here we tested whether sleep restriction in early adolescence produces the same sleep stage changes observed on school nights across adolescence. Methods: All-night sleep EEG was recorded in 76 children ranging in age from 9.9 to 14.0 years. Each participant kept 3 different sleep schedules that consisted of 3 nights of 8.5 h in bed followed by 4 nights of either 7, 8.5, or 10 h in bed. Sleep stage durations and NREM delta EEG activity were compared across the 3 time in bed conditions. Results: Shortening time in bed from 10 to 7 hours reduced sleep duration by approximately 2 hours, roughly equal to the decrease in sleep duration we recorded longitudinally across adolescence. However, sleep restriction significantly reduced both NREM (by 83 min) and REM (by 47 min) sleep. Sleep restriction did not affect NREM delta EEG activity. Conclusions: Our findings suggest that the selective NREM reduction and the small increase in REM we observed longitudinally across 9–18 years are not produced by sleep restriction. We hypothesize that the selective NREM decline reflects adolescent brain maturation (synaptic elimination) that reduces the need for the restorative processes of NREM sleep. Citation: Campbell IG, Kraus AM, Burright CS, Feinberg I. Restricting time in bed in early adolescence reduces both NREM and REM sleep but does not increase slow wave EEG. SLEEP 2016;39(9):1663–1670. PMID:27397569

The Improvement of Sleep by Oral Intake of GABA and Apocynum venetum Leaf Extract.

PubMed

Yamatsu, Atsushi; Yamashita, Yusuke; Maru, Isafumi; Yang, Jinwei; Tatsuzaki, Jin; Kim, Mujo

2015-01-01

The effects of two food materials, γ-aminobutyric acid (GABA) produced by natural fermentation and Apocynum venetum leaf extract (AVLE), on the improvement of sleep were investigated in humans. The electroencephalogram (EEG) test revealed that oral administration of GABA (100 mg) and AVLE (50 mg) had beneficial effects on sleep. GABA shortened sleep latency by 5.3 min and AVLE increased non-rapid eye movement (REM) sleep time by 7.6%. Simultaneous intake of GABA and AVLE shortened sleep latency by 4.3 min and increased non-REM sleep time by 5.1%. The result of questionnaires showed that GABA and AVLE enabled subjects to realize the effects on sleep. These results mean that GABA can help people to fall asleep quickly, AVLE induces deep sleep, and they function complementarily with simultaneous intake. Since both GABA and AVLE are materials of foods and have been ingested for a long time, they can be regarded as safe and appropriate for daily intake in order to improve the quality of sleep.

Different sleep onset criteria at the multiple sleep latency test (MSLT): an additional marker to differentiate central nervous system (CNS) hypersomnias.

PubMed

Pizza, Fabio; Vandi, Stefano; Detto, Stefania; Poli, Francesca; Franceschini, Christian; Montagna, Pasquale; Plazzi, Giuseppe

2011-03-01

Excessive daytime sleepiness (EDS) has different correlates in non-rapid eye movement (NREM) [idiopathic hypersomnia (IH) without long sleep time] and REM sleep [narcolepsy without cataplexy (NwoC) and narcolepsy with cataplexy (NC)]-related hypersomnias of central origin. We analysed sleep onset characteristics at the multiple sleep latency test (MSLT) applying simultaneously two sleep onset criteria in 44 NC, seven NwoC and 16 IH consecutive patients referred for subjective EDS complaint. Sleep latency (SL) at MSLT was assessed both as the time elapsed to the occurrence of a single epoch of sleep Stage 1 NREM (SL) and of unequivocal sleep [three sleep Stage 1 NREM epochs or any other sleep stage epoch, sustained SL (SusSL)]. Idiopathic hypersomnia patients showed significantly (P<0.0001) longer SusSL than SL (7.7±2.5 versus 5.6±1.3 min, respectively) compared to NwoC (5.8±2.5 versus 5.3±2.2 min) and NC patients (4.1±3 versus 3.9±3 min). A mean difference threshold between SusSL and SL ≥27 s reached a diagnostic value to discriminate IH versus NC and NwoC sufferers (sensitivity 88%; specificity 82%). Moreover, NC patients showed better subjective sleepiness perception than NwoC and IH cases in the comparison between naps with or without sleep occurrence. Simultaneous application of the two widely used sleep onset criteria differentiates IH further from NC and NwoC patients: IH fluctuate through a wake-Stage 1 NREM sleep state before the onset of sustained sleep, while NC and NwoC shift abruptly into a sustained sleep. The combination of SusSL and SL determination at MSLT should be tested as an additional objective differential criterion for EDS disorders. © 2010 European Sleep Research Society.

Sleep-related declarative memory consolidation and verbal replay during sleep talking in patients with REM sleep behavior disorder.

PubMed

Uguccioni, Ginevra; Pallanca, Olivier; Golmard, Jean-Louis; Dodet, Pauline; Herlin, Bastien; Leu-Semenescu, Smaranda; Arnulf, Isabelle

2013-01-01

To determine if sleep talkers with REM sleep behavior disorder (RBD) would utter during REM sleep sentences learned before sleep, and to evaluate their verbal memory consolidation during sleep. Eighteen patients with RBD and 10 controls performed two verbal memory tasks (16 words from the Free and Cued Selective Reminding Test and a 220-263 word long modified Story Recall Test) in the evening, followed by nocturnal video-polysomnography and morning recall (night-time consolidation). In 9 patients with RBD, daytime consolidation (morning learning/recall, evening recall) was also evaluated with the modified Story Recall Test in a cross-over order. Two RBD patients with dementia were studied separately. Sleep talking was recorded using video-polysomnography, and the utterances were compared to the studied texts by two external judges. Sleep-related verbal memory consolidation was maintained in patients with RBD (+24±36% words) as in controls (+9±18%, p=0.3). The two demented patients with RBD also exhibited excellent nighttime consolidation. The post-sleep performance was unrelated to the sleep measures (including continuity, stages, fragmentation and apnea-hypopnea index). Daytime consolidation (-9±19%) was worse than night-time consolidation (+29±45%, p=0.03) in the subgroup of 9 patients with RBD. Eleven patients with RBD spoke during REM sleep and pronounced a median of 20 words, which represented 0.0003% of sleep with spoken language. A single patient uttered a sentence that was judged to be semantically (but not literally) related to the text learned before sleep. Verbal declarative memory normally consolidates during sleep in patients with RBD. The incorporation of learned material within REM sleep-associated sleep talking in one patient (unbeknownst to himself) at the semantic level suggests a replay at a highly cognitive creative level.

Sleep-Related Declarative Memory Consolidation and Verbal Replay during Sleep Talking in Patients with REM Sleep Behavior Disorder

PubMed Central

Uguccioni, Ginevra; Pallanca, Olivier; Golmard, Jean-Louis; Dodet, Pauline; Herlin, Bastien; Leu-Semenescu, Smaranda; Arnulf, Isabelle

2013-01-01

Objective To determine if sleep talkers with REM sleep behavior disorder (RBD) would utter during REM sleep sentences learned before sleep, and to evaluate their verbal memory consolidation during sleep. Methods Eighteen patients with RBD and 10 controls performed two verbal memory tasks (16 words from the Free and Cued Selective Reminding Test and a 220-263 word long modified Story Recall Test) in the evening, followed by nocturnal video-polysomnography and morning recall (night-time consolidation). In 9 patients with RBD, daytime consolidation (morning learning/recall, evening recall) was also evaluated with the modified Story Recall Test in a cross-over order. Two RBD patients with dementia were studied separately. Sleep talking was recorded using video-polysomnography, and the utterances were compared to the studied texts by two external judges. Results Sleep-related verbal memory consolidation was maintained in patients with RBD (+24±36% words) as in controls (+9±18%, p=0.3). The two demented patients with RBD also exhibited excellent nighttime consolidation. The post-sleep performance was unrelated to the sleep measures (including continuity, stages, fragmentation and apnea-hypopnea index). Daytime consolidation (-9±19%) was worse than night-time consolidation (+29±45%, p=0.03) in the subgroup of 9 patients with RBD. Eleven patients with RBD spoke during REM sleep and pronounced a median of 20 words, which represented 0.0003% of sleep with spoken language. A single patient uttered a sentence that was judged to be semantically (but not literally) related to the text learned before sleep. Conclusion Verbal declarative memory normally consolidates during sleep in patients with RBD. The incorporation of learned material within REM sleep-associated sleep talking in one patient (unbeknownst to himself) at the semantic level suggests a replay at a highly cognitive creative level. PMID:24349492

Habitual short sleep impacts frontal switch mechanism in attention to novelty.

PubMed

Gumenyuk, Valentina; Roth, Thomas; Korzyukov, Oleg; Jefferson, Catherine; Bowyer, Susan; Drake, Christopher L

2011-12-01

Reduced time in bed relative to biological sleep need is common. The impact of habitual short sleep on auditory attention has not been studied to date. In the current study, we utilized novelty oddball tasks to evaluate the effect of habitual short sleep on brain function underlying attention control processes measured by the mismatch negativity (MMN, index of pre-attentive stage), P3a (attention-dependent), and P3b (memory-dependent) event related brain potentials (ERPs). An extended time in bed in a separate study was used to evaluate the possible reversal of the impairments of these processes in habitual short sleepers. Ten self-defined short sleepers (total sleep time [TST] ≤ 6 h) and 9 normal-sleeping subjects with TST 7-8 h, participated. ERPs were recorded via a 64-channel EEG system. Two test conditions: "ignore" and "attend" were implemented. The ERPs were analyzed and compared between groups on the 2 task conditions and frontal/central/parietal electrodes by 3-factor ANOVA. Sleep diary data were compared between groups by t-test. Sleep was recorded by the Zeo sleep monitoring system for a week in both habitual and extended sleep conditions at home. The main findings of the present study show that short sleeping individuals had deficiency in activity of the MMN and P3a brain responses over frontal areas compared to normal-sleeping subjects. The P3b amplitude was increased over frontal areas and decreased over parietal with respect to the control group. Extension of time in bed for one week increased TST (from 5.7 h to 7.4 h), and concomitantly MMN amplitude increased from -0.1 μV up to -1.25 μV over frontal areas. Reduced time in bed is associated with deficiency of the neuronal process associated with change detection, which may recover after one week of sleep extension, whereas attention-dependent neural processes do not normalize after this period of time in habitually short sleeping individuals and may require longer recovery periods.

Sleep Can Reduce the Testing Effect: It Enhances Recall of Restudied Items but Can Leave Recall of Retrieved Items Unaffected

ERIC Educational Resources Information Center

Bäuml, Karl-Heinz T.; Holterman, Christoph; Abel, Magdalena

2014-01-01

The testing effect refers to the finding that retrieval practice in comparison to restudy of previously encoded contents can improve memory performance and reduce time-dependent forgetting. Naturally, long retention intervals include both wake and sleep delay, which can influence memory contents differently. In fact, sleep immediately after…

Assessing the benefits of napping and short rest breaks on processing speed in sleep-restricted adolescents.

PubMed

Lim, Julian; Lo, June C; Chee, Michael W L

2017-04-01

Achievement-oriented adolescents often study long hours under conditions of chronic sleep restriction, adversely affecting cognitive function. Here, we studied how napping and rest breaks (interleaved off-task periods) might ameliorate the negative effects of sleep restriction on processing speed. Fifty-seven healthy adolescents (26 female, age = 15-19 years) participated in a 15-day live-in protocol. All participants underwent sleep restriction (5 h time-in-bed), but were then randomized into two groups: one of these groups received a daily 1-h nap opportunity. Data from seven of the study days (sleep restriction days 1-5, and recovery days 1-2) are reported here. The Blocked Symbol Decoding Test, administered once a day, was used to assess time-on-task effects and the effects of rest breaks on processing speed. Controlling for baseline differences, participants who took a nap demonstrated faster speed of processing and greater benefit across testing sessions from practice. These participants were also affected significantly less by time-on-task effects. In contrast, participants who did not receive a nap benefited more from the rest breaks that were permitted between blocks of the test. Our results indicate that napping partially reverses the detrimental effects of sleep restriction on processing speed. However, rest breaks have a greater effect as a countermeasure against poor performance when sleep pressure is higher. These data add to the growing body of evidence showing the importance of sleep for good cognitive functioning in adolescents, and suggest that more frequent rest breaks might be important in situations where sleep loss is unavoidable. © 2017 European Sleep Research Society.

Timing and Variability of Postpartum Sleep in Relation to Daytime Performance

PubMed Central

McBean, Amanda L.; Montgomery-Downs, Hawley E.

2013-01-01

Postpartum women have highly disturbed sleep, also known as sleep fragmentation. Fragmentation extends their total sleep period, also disrupting sleep timing. A stable and earlier sleep period among non-postpartum populations are related to better performance, physical health, and mental health. However, sleep timing has not been examined among postpartum women who are also vulnerable to daytime impairment. The study objective was to examine how the timing and regularity of sleep during the early postpartum period are related to daytime functioning across postpartum weeks 2-13. In this field-based study, 71 primiparous women wore an actigraph, a small wrist-worn device that monitors sleep and sleep timing, for the 12-week study period. Mothers self-administered a 5-minute psychomotor vigilance test (PVT) each morning to evaluate the number of >500ms response lapses. They also completed a Morningness-Eveningness scale at the beginning of the study to identify chronotype. After controlling for maternal age, earlier sleep timing was associated with significantly fewer PVT lapses at postpartum weeks 9,12; a more stable sleep midpoint was associated with significantly fewer PVT lapses at postpartum weeks 2,5-13. Earlier sleep midpoints were related to more stable sleep midpoints at postpartum week 2 and a morning-type chronotype. An earlier sleep midpoint was also associated with a reduced slope of worsening PVT lapses across weeks. Across the first 12 postpartum weeks, women with earlier or more stable sleep periods had less daytime impairment than women with later or more variable sleep midpoints. Postpartum women with earlier sleep midpoints also showed less severe decrements in performance across time, which has been attributed to cumulative impacts of sleep disturbance. These data suggest the sleep period, in addition to sleep duration and fragmentation, should be more closely examined, particularly among vulnerable women, as it may affect the neurobehavioral performance of new mothers. PMID:24041725

Restricting Time in Bed in Early Adolescence Reduces Both NREM and REM Sleep but Does Not Increase Slow Wave EEG.

PubMed

Campbell, Ian G; Kraus, Amanda M; Burright, Christopher S; Feinberg, Irwin

2016-09-01

School night total sleep time decreases across adolescence (9-18 years) by 10 min/year. This decline is comprised entirely of a selective decrease in NREM sleep; REM sleep actually increases slightly. Decreasing sleep duration across adolescence is often attributed to insufficient time in bed. Here we tested whether sleep restriction in early adolescence produces the same sleep stage changes observed on school nights across adolescence. All-night sleep EEG was recorded in 76 children ranging in age from 9.9 to 14.0 years. Each participant kept 3 different sleep schedules that consisted of 3 nights of 8.5 h in bed followed by 4 nights of either 7, 8.5, or 10 h in bed. Sleep stage durations and NREM delta EEG activity were compared across the 3 time in bed conditions. Shortening time in bed from 10 to 7 hours reduced sleep duration by approximately 2 hours, roughly equal to the decrease in sleep duration we recorded longitudinally across adolescence. However, sleep restriction significantly reduced both NREM (by 83 min) and REM (by 47 min) sleep. Sleep restriction did not affect NREM delta EEG activity. Our findings suggest that the selective NREM reduction and the small increase in REM we observed longitudinally across 9-18 years are not produced by sleep restriction. We hypothesize that the selective NREM decline reflects adolescent brain maturation (synaptic elimination) that reduces the need for the restorative processes of NREM sleep. © 2016 Associated Professional Sleep Societies, LLC.

Validation of Sleep-Tracking Technology Compared with Polysomnography in Adolescents.

PubMed

de Zambotti, Massimiliano; Baker, Fiona C; Colrain, Ian M

2015-09-01

To evaluate the accuracy in measuring nighttime sleep of a fitness tracker (Jawbone UP) compared to polysomnography (PSG). Jawbone UP and PSG data were simultaneously collected from adolescents during an overnight laboratory recording. Agreements between Jawbone UP and PSG sleep outcomes were analyzed using paired t tests and Bland-Altman plots. Multiple regressions were used to investigate which PSG sleep measures predicted Jawbone UP "Sound sleep" and "Light sleep." SRI International Human Sleep Laboratory. Sixty-five healthy adolescents (28 females, mean age ± standard deviation [SD]: 15.8 ± 2.5 y). N/A. Outcomes showed good agreements between Jawbone UP and PSG for total sleep time (mean differences ± SD: -10.0 ± 20.5 min), sleep efficiency (mean differences ± SD: -1.9 ± 4.2 %), and wake after sleep onset (WASO) (mean differences ± SD: 10.6 ± 14.7 min). Overall, Jawbone UP overestimated PSG total sleep time and sleep efficiency and underestimated WASO but differences were small and, on average, did not exceed clinically meaningful cutoffs of > 30 min for total sleep time and > 5% for sleep efficiency. Multiple regression models showed that Jawbone UP "Sound sleep" measure was predicted by PSG time in N2 (β = 0.25), time in rapid eye movement (β = 0.29), and arousal index (β = -0.34). Jawbone UP "Light sleep" measure was predicted by PSG time in N2 (β = 0.48), time in N3 (β = 0.49), arousal index (β = 0.38) and awakening index (β = 0.28). Jawbone UP showed a progression from slight overestimation to underestimation of total sleep time and sleep efficiency with advancing age. All relationships were similar in boys and girls. Jawbone UP shows good agreement with polysomnography in measures of total sleep time and wake after sleep onset in adolescent boys and girls. Further validation is needed in other age groups and clinical populations before advocating use of these inexpensive and easy-to-use devices in clinical sleep medicine and research. © 2015 Associated Professional Sleep Societies, LLC.

Cardiovascular Stress Reactivity and Carotid Intima-Media Thickness: The Buffering Role of Slow-Wave Sleep.

PubMed

Brindle, Ryan C; Duggan, Katherine A; Cribbet, Matthew R; Kline, Christopher E; Krafty, Robert T; Thayer, Julian F; Mulukutla, Suresh R; Hall, Martica H

2018-04-01

Exaggerated cardiovascular reactivity to acute psychological stress has been associated with increased carotid intima-media thickness (IMT). However, interstudy variability in this relationship suggests the presence of moderating factors. The current study aimed to test the hypothesis that poor nocturnal sleep, defined as short total sleep time or low slow-wave sleep, would moderate the relationship between cardiovascular reactivity and IMT. Participants (N = 99, 65.7% female, age = 59.3 ± 9.3 years) completed a two-night laboratory sleep study and cardiovascular examination where sleep and IMT were measured. The multisource interference task was used to induce acute psychological stress, while systolic and diastolic blood pressure and heart rate were monitored. Moderation was tested using the PROCESS framework in SPSS. Slow-wave sleep significantly moderated the relationship between all cardiovascular stress reactivity variables and IMT (all pinteraction ≤ .048, all ΔRinteraction ≥ .027). Greater stress reactivity was associated with higher IMT values in the low slow-wave sleep group and lower IMT values in the high slow-wave sleep group. No moderating effects of total sleep time were observed. The results provide evidence that nocturnal slow-wave sleep moderates the relationship between cardiovascular stress reactivity and IMT and may buffer the effect of daytime stress-related disease processes.

Feasibility and Emotional Impact of Experimentally Extending Sleep in Short-Sleeping Adolescents.

PubMed

Van Dyk, Tori R; Zhang, Nanhua; Catlin, Perry A; Cornist, Kaylin; McAlister, Shealan; Whitacre, Catharine; Beebe, Dean W

2017-09-01

Published experimental sleep manipulation protocols for adolescents have been limited to the summer, limiting causal conclusions about how short sleep affects them on school nights, when they are most likely to restrict their sleep. This study assesses the feasibility and emotional impact of a school-night sleep manipulation protocol to test the effects of lengthening sleep in habitually short-sleeping adolescents. High school students aged 14-18 years who habitually slept 5-7 hours on school nights participated in a 5-week experimental sleep manipulation protocol. Participants completed a baseline week followed in randomized counterbalanced order by two experimental conditions lasting 2 weeks each: prescribed habitual sleep (HAB; sleep time set to match baseline) and sleep extension (EXT; 1.5-hour increase in time in bed from HAB). All sleep was obtained at home, monitored with actigraphy. Data on adherence, protocol acceptability, mood and behavior were collected at the end of each condition. Seventy-six adolescents enrolled in the study, with 54 retained through all 5 weeks. Compared to HAB, during EXT, participants averaged an additional 72.6 minutes/night of sleep (p < .001) and had reduced symptoms of sleepiness, anger, vigor, fatigue, and confusion (p < .05). The large majority of parents (98%) and adolescents (100%) said they would "maybe" or "definitely" recommend the study to another family. An experimental, school-night sleep manipulation protocol can be feasibly implemented which directly tests the potential protective effects of lengthening sleep. Many short-sleeping adolescents would benefit emotionally from sleeping longer, supporting public health efforts to promote adolescent sleep on school nights. © Sleep Research Society 2017. Published by Oxford University Press on behalf of the Sleep Research Society. All rights reserved. For permissions, please e-mail journals.permissions@oup.com.

Idiopathic Hypersomnia with and without Long Sleep Time: A Controlled Series of 75 Patients

PubMed Central

Vernet, Cyrille; Arnulf, Isabelle

2009-01-01

Objective: To characterize the clinical, psychological, and sleep pattern of idiopathic hypersomnia with and without long sleep time, and provide normative values for 24-hour polysomnography. Setting: University Hospital Design: Controlled, prospective cohort Participants: 75 consecutive patients (aged 34 ± 12 y) with idiopathic hypersomnia and 30 healthy matched controls. Intervention: Patients and controls underwent during 48 hours a face-to face interview, questionnaires, human leukocyte antigen genotype, a night polysomnography and multiple sleep latency test (MSLT), followed by 24-h ad libitum sleep monitoring. Results: Hypersomniacs had more fatigue, higher anxiety and depression scores, and more frequent hypnagogic hallucinations (24%), sleep paralysis (28%), sleep drunkenness (36%), and unrefreshing naps (46%) than controls. They were more frequently evening types. DQB1*0602 genotype was similarly found in hypersomniacs (24.2%) and controls (19.2%). Hypersomniacs had more frequent slow wave sleep after 06:00 than controls. During 24-h polysomnography, the 95% confidence interval for total sleep time was 493–558 min in controls, versus 672–718 min in hypersomniacs. There were 40 hypersomniacs with and 35 hypersomniacs without long ( > 600 min) sleep time. The hypersomniacs with long sleep time were younger (29 ± 10 vs 40 ± 13 y, P = 0.0002), slimmer (body mass index: 26 ± 5 vs 23 ± 4 kg/m2; P = 0.005), and had lower Horne-Ostberg scores and higher sleep efficiencies than those without long sleep time. MSLT latencies were normal ( > 8 min) in 71% hypersomniacs with long sleep time. Conclusions: Hypersomnia, especially with long sleep time, is frequently associated with evening chronotype and young age. It is inadequately diagnosed using MSLT. Citation: Vernet C; Arnulf I. Idiopathic Hypersomnia with and without Long Sleep Time: A Controlled Series of 75 Patients. SLEEP 2009;32(6):753-759. PMID:19544751

Sensitivity and validity of psychometric tests for assessing driving impairment: effects of sleep deprivation.

PubMed

Jongen, Stefan; Perrier, Joy; Vuurman, Eric F; Ramaekers, Johannes G; Vermeeren, Annemiek

2015-01-01

To assess drug induced driving impairment, initial screening is needed. However, no consensus has been reached about which initial screening tools have to be used. The present study aims to determine the ability of a battery of psychometric tests to detect performance impairing effects of clinically relevant levels of drowsiness as induced by one night of sleep deprivation. Twenty four healthy volunteers participated in a 2-period crossover study in which the highway driving test was conducted twice: once after normal sleep and once after one night of sleep deprivation. The psychometric tests were conducted on 4 occasions: once after normal sleep (at 11 am) and three times during a single night of sleep deprivation (at 1 am, 5 am, and 11 am). On-the-road driving performance was significantly impaired after sleep deprivation, as measured by an increase in Standard Deviation of Lateral Position (SDLP) of 3.1 cm compared to performance after a normal night of sleep. At 5 am, performance in most psychometric tests showed significant impairment. As expected, largest effect sizes were found on performance in the Psychomotor Vigilance Test (PVT). Large effects sizes were also found in the Divided Attention Test (DAT), the Attention Network Test (ANT), and the test for Useful Field of View (UFOV) at 5 and 11 am during sleep deprivation. Effects of sleep deprivation on SDLP correlated significantly with performance changes in the PVT and the DAT, but not with performance changes in the UFOV. From the psychometric tests used in this study, the PVT and DAT seem most promising for initial evaluation of drug impairment based on sensitivity and correlations with driving impairment. Further studies are needed to assess the sensitivity and validity of these psychometric tests after benchmark sedative drug use.

Do later wake times and increased sleep duration of 12th graders result in more studying, higher grades, and improved SAT/ACT test scores?

PubMed

Cole, James S

2016-09-01

The aim of this study was to investigate the relationship between sleep duration, wake time, and hours studying on high school grades and performance on the Scholastic Aptitude Test (SAT)/ American College Testing (ACT) college entrance exams. Data were collected from 13,071 recently graduated high school seniors who were entering college in the fall of 2014. A column proportions z test with a Bonferroni adjustment was used to analyze proportional differences. Analysis of covariance (ANCOVA) was used to examine mean group differences. Students who woke up prior to 6 a.m. and got less than 8 h of sleep (27 %) were significantly more likely to report studying 11 or more hours per week (30 %), almost double the rate compared to students who got more than 8 h of sleep and woke up the latest (16 %). Post hoc results revealed students who woke up at 7 a.m. or later reported significantly higher high school grades than all other groups (p < 0.001), with the exception of those students who woke up between 6:01 a.m. and 7:00 a.m. and got eight or more hours of sleep. The highest reported SAT/ACT scores were from the group that woke up after 7 a.m. but got less than 8 h sleep (M = 1099.5). Their scores were significantly higher than all other groups. This study provides additional evidence that increased sleep and later wake time are associated with increased high school grades. However, this study also found that students who sleep the longest also reported less studying and lower SAT/ACT scores.

Differences in sleep habits, study time, and academic performance between US-born and foreign-born college students.

PubMed

Eliasson, Arne H; Eliasson, Arn H; Lettieri, Christopher J

2017-05-01

To inform the design of a sleep improvement program for college students, we assessed academic performance, sleep habits, study hours, and extracurricular time, hypothesizing that there would be differences between US-born and foreign-born students. Questionnaires queried participants on bedtimes, wake times, nap frequency, differences in weekday and weekend sleep habits, study hours, grade point average, time spent at paid employment, and other extracurricular activities. Comparisons were made using chi square tests for categorical data and t tests for continuous data between US-born and foreign-born students. Of 120 participants (55 % women) with racial diversity (49 whites, 18 blacks, 26 Hispanics, 14 Asians, and 13 other), 49 (41 %) were foreign-born. Comparisons between US-born and foreign-born students showed no differences in average age or gender though US-born had more whites. There were no differences between US-born and foreign-born students for grade point averages, weekday bedtimes, wake times, or total sleep times. However, US-born students averaged 50 min less study time per day (p = 0.01), had almost 9 h less paid employment per week (14.5 vs 23.4 h per week, p = 0.001), and stayed up to socialize more frequently (63 vs 43 %, p = 0.03). Foreign-born students awakened an hour earlier and averaged 40 min less sleep per night on weekends. Cultural differences among college students have a profound effect on sleep habits, study hours, and extracurricular time. The design of a sleep improvement program targeting a population with diverse cultural backgrounds must factor in such behavioral variations in order to have relevance and impact.

Habitual Short Sleep Impacts Frontal Switch Mechanism in Attention to Novelty

PubMed Central

Gumenyuk, Valentina; Roth, Thomas; Korzyukov, Oleg; Jefferson, Catherine; Bowyer, Susan; Drake, Christopher L.

2011-01-01

Study Objectives: Reduced time in bed relative to biological sleep need is common. The impact of habitual short sleep on auditory attention has not been studied to date. In the current study, we utilized novelty oddball tasks to evaluate the effect of habitual short sleep on brain function underlying attention control processes measured by the mismatch negativity (MMN, index of pre-attentive stage), P3a (attention-dependent), and P3b (memory-dependent) event related brain potentials (ERPs). An extended time in bed in a separate study was used to evaluate the possible reversal of the impairments of these processes in habitual short sleepers. Methods: Ten self-defined short sleepers (total sleep time [TST] ≤ 6h) and 9 normal-sleeping subjects with TST 7-8 h, participated. ERPs were recorded via a 64-channel EEG system. Two test conditions: “ignore” and “attend” were implemented. The ERPs were analyzed and compared between groups on the 2 task conditions and frontal/central/parietal electrodes by 3-factor ANOVA. Sleep diary data were compared between groups by t-test. Sleep was recorded by the Zeo sleep monitoring system for a week in both habitual and extended sleep conditions at home. Results: The main findings of the present study show that short sleeping individuals had deficiency in activity of the MMN and P3a brain responses over frontal areas compared to normal-sleeping subjects. The P3b amplitude was increased over frontal areas and decreased over parietal with respect to the control group. Extension of time in bed for one week increased TST (from 5.7 h to 7.4 h), and concomitantly MMN amplitude increased from −0.1μV up to −1.25 μV over frontal areas. Conclusions: Reduced time in bed is associated with deficiency of the neuronal process associated with change detection, which may recover after one week of sleep extension, whereas attention-dependent neural processes do not normalize after this period of time in habitually short sleeping individuals and may require longer recovery periods. Citation: Gumenyuk V; Roth T; Korzyukov O; Jefferson C; Bowyer S; Drake CL. Habitual short sleep impacts frontal switch mechanism in attention to novelty. SLEEP 2011;34(12):1659-1670. PMID:22131603

Effects of a Single Night of Postpartum Sleep on Childless Women’s Daytime Functioning

PubMed Central

McBean, Amanda L.; Kinsey, Steven G.; Montgomery-Downs, Hawley E.

2017-01-01

Study Objectives The maternal postpartum period is characterized by sleep fragmentation, which is associated with daytime impairment, mental health disturbances, and changes in melatonin patterns. In addition to sleep fragmentation, women undergo a complex set of physiological and environmental changes upon entering the postpartum period, confounding our understanding of effects of postpartum sleep disturbance. The primary study aim was to understand the basic impact of a single night of postpartum-like sleep fragmentation on sleep architecture, nocturnal melatonin levels, mood, daytime sleepiness, and neurobehavioral performance. Measurements and Results For one week prior to entry into the laboratory, eleven healthy nulliparous women kept a stable sleep-wake schedule (verified via actigraphy). Participants contributed three consecutive nights of laboratory overnight polysomnography: (1) a habituation/sleep disorder screening night; (2) a baseline night; and (3) a sleep fragmentation night, when participants were awakened three times for ~30 min each. Self-reported sleep quality and mood (Profile of Mood States Survey) both decreased significantly after sleep fragmentation compared to baseline measurements. Unexpectedly, daytime sleepiness (Multiple Sleep Latency Test) decreased significantly after sleep fragmentation. Experimental fragmentation had no significant effect on time spent in nocturnal sleep stages, urinary 6-sulphatoxymelatonin concentration, or psychomotor vigilance test performance. Participants continued to provide actigraphy data, and daily PVTs and self-reported sleep quality assessments at home for one week following sleep fragmentation; these assessments did not differ from baseline values. Conclusions While there were no changes in measured physiological components of a single night of postpartum-like experimental sleep fragmentation, there were decreases in self-reported measures of mood and sleep quality. Future research should examine the effects of multiple nights of modeling postpartum-like sleep fragmentation on objective measures of sleep and daytime functioning. PMID:26776447

Efficacy of cognitive-behavioral therapy for insomnia associated with traumatic brain injury: a single-case experimental design.

PubMed

Ouellet, Marie-Christine; Morin, Charles M

2007-12-01

To test the efficacy of a cognitive-behavioral therapy (CBT) for insomnia in persons having sustained traumatic brain injury (TBI). Single-case design with multiple baselines across participants. Outpatient rehabilitation center. Eleven subjects having sustained mild to severe TBI who developed insomnia after the injury. Eight-week CBT for insomnia including stimulus control, sleep restriction, cognitive restructuring, sleep hygiene education, and fatigue management. Total wake time, sleep efficiency, and diagnostic criteria. Visual analyses, corroborated by intervention time series analyses and t tests, revealed clinically and statistically significant reductions in total wake time and sleep efficiency for 8 (73%) of 11 participants. An average reduction of 53.9% in total wake time was observed across participants from pre- to post-treatment. Progress was in general well maintained at the 1-month and 3-month follow-ups. The average sleep efficiency augmented significantly from pretreatment (77.2%) to post-treatment (87.9%), and also by the 3-month follow-up (90.9%). Improvements in sleep were accompanied by a reduction in symptoms of general and physical fatigue. The results of this study show that psychologic interventions for insomnia are a promising therapeutic avenue for TBI survivors.

Sleep, sleepiness, and circadian rhythmicity in aircrews operating on transatlantic routes

NASA Technical Reports Server (NTRS)

Wegmann, Hans M.; Gundel, Alexander; Samel, Alexander; Schwartz, Edwin; Naumann, Martin

1986-01-01

A two-phase study was performed on B-747 crew members operating on regular passenger flights with 9-h time difference. In phase I, sleep-log surveys were obtained. The results for the layover period indicate congruent sleep patterns with shifts in sleep onset less than 9 h; sleep duration was prolonged. Phase II consisted of polygraphic sleep recordings and multiple sleep latency tests (MSLTs) applied to four cockpit crews in a baseline period, during the layover, and after return to home base. During the layover, mean bed times were shifted by about 4.5 h, and sleep was disturbed by early and prolonged awakenings which led to a reduction of sleep efficiency. The ECG and rectal temperature recordings gave evidence for a desynchronization of the circadian system and an internal dissociation of different body functions.

Nocturnal Sleep Dynamics Identify Narcolepsy Type 1.

PubMed

Pizza, Fabio; Vandi, Stefano; Iloti, Martina; Franceschini, Christian; Liguori, Rocco; Mignot, Emmanuel; Plazzi, Giuseppe

2015-08-01

To evaluate the reliability of nocturnal sleep dynamics in the differential diagnosis of central disorders of hypersomnolence. Cross-sectional. Sleep laboratory. One hundred seventy-five patients with hypocretin-deficient narcolepsy type 1 (NT1, n = 79), narcolepsy type 2 (NT2, n = 22), idiopathic hypersomnia (IH, n = 22), and "subjective" hypersomnolence (sHS, n = 52). None. Polysomnographic (PSG) work-up included 48 h of continuous PSG recording. From nocturnal PSG conventional sleep macrostructure, occurrence of sleep onset rapid eye movement period (SOREMP), sleep stages distribution, and sleep stage transitions were calculated. Patient groups were compared, and receiver operating characteristic (ROC) curve analysis was used to test the diagnostic utility of nocturnal PSG data to identify NT1. Sleep macrostructure was substantially stable in the 2 nights of each diagnostic group. NT1 and NT2 patients had lower latency to rapid eye movement (REM) sleep, and NT1 patients showed the highest number of awakenings, sleep stage transitions, and more time spent in N1 sleep, as well as most SOREMPs at daytime PSG and at multiple sleep latency test (MSLT) than all other groups. ROC curve analysis showed that nocturnal SOREMP (area under the curve of 0.724 ± 0.041, P < 0.0001), percent of total sleep time spent in N1 (0.896 ± 0.023, P < 0.0001), and the wakefulness-sleep transition index (0.796 ± 0.034, P < 0.0001) had a good sensitivity and specificity profile to identify NT1 sleep, especially when used in combination (0.903 ± 0.023, P < 0.0001), similarly to SOREMP number at continuous daytime PSG (0.899 ± 0.026, P < 0.0001) and at MSLT (0.956 ± 0.015, P < 0.0001). Sleep macrostructure (i.e. SOREMP, N1 timing) including stage transitions reliably identifies hypocretin-deficient narcolepsy type 1 among central disorders of hypersomnolence. © 2015 Associated Professional Sleep Societies, LLC.

Effect of auricular acupressure for postpartum insomnia: an uncontrolled clinical trial.

PubMed

Ko, Yi-Li; Lin, Shih-Chi; Lin, Pi-Chu

2016-02-01

This study examined the effects of auricular acupressure therapy on women with postpartum insomnia. Postpartum women generally have poor sleep quality because of frequent night-time breastfeeding during the first month after giving birth. A one-group pretest/post-test quasi-experiment was conducted. A convenience sampling method was used to recruit participants at a postpartum centre (doing-the-month centre) in Northern Taiwan, from January 2014-July 2014. Thirty women with postpartum insomnia received auricular acupressure therapy on one auricular point (Shenmen point pressing) four times a day for 14 days. The Chinese version of the Pittsburgh Sleep Quality Index was used to assess sleep quality before and after the 14-day treatment. After the 14-day auricular acupressure treatment, the Pittsburgh Sleep Quality Index total scores of the women decreased from 8·7 (pretest) to 5·57 (post-test, 36% reduction). Scores on the subscales of the Pittsburgh Sleep Quality Index, including sleep quality, sleep latency, sleep duration and sleep disturbance, also statistically improved (p < 0·05). Hormone changes and frequent breastfeeding were identified as characteristics that may exacerbate poor sleep quality of postpartum women, for whom the auricular acupressure intervention may effectively improve sleep quality. Auricular acupressure can be an alternative complementary therapy to aid postpartum women with insomnia in improving sleep quality. © 2015 John Wiley & Sons Ltd.

Direct Measurements of Smartphone Screen-Time: Relationships with Demographics and Sleep.

PubMed

Christensen, Matthew A; Bettencourt, Laura; Kaye, Leanne; Moturu, Sai T; Nguyen, Kaylin T; Olgin, Jeffrey E; Pletcher, Mark J; Marcus, Gregory M

2016-01-01

Smartphones are increasingly integrated into everyday life, but frequency of use has not yet been objectively measured and compared to demographics, health information, and in particular, sleep quality. The aim of this study was to characterize smartphone use by measuring screen-time directly, determine factors that are associated with increased screen-time, and to test the hypothesis that increased screen-time is associated with poor sleep. We performed a cross-sectional analysis in a subset of 653 participants enrolled in the Health eHeart Study, an internet-based longitudinal cohort study open to any interested adult (≥ 18 years). Smartphone screen-time (the number of minutes in each hour the screen was on) was measured continuously via smartphone application. For each participant, total and average screen-time were computed over 30-day windows. Average screen-time specifically during self-reported bedtime hours and sleeping period was also computed. Demographics, medical information, and sleep habits (Pittsburgh Sleep Quality Index-PSQI) were obtained by survey. Linear regression was used to obtain effect estimates. Total screen-time over 30 days was a median 38.4 hours (IQR 21.4 to 61.3) and average screen-time over 30 days was a median 3.7 minutes per hour (IQR 2.2 to 5.5). Younger age, self-reported race/ethnicity of Black and "Other" were associated with longer average screen-time after adjustment for potential confounders. Longer average screen-time was associated with shorter sleep duration and worse sleep-efficiency. Longer average screen-times during bedtime and the sleeping period were associated with poor sleep quality, decreased sleep efficiency, and longer sleep onset latency. These findings on actual smartphone screen-time build upon prior work based on self-report and confirm that adults spend a substantial amount of time using their smartphones. Screen-time differs across age and race, but is similar across socio-economic strata suggesting that cultural factors may drive smartphone use. Screen-time is associated with poor sleep. These findings cannot support conclusions on causation. Effect-cause remains a possibility: poor sleep may lead to increased screen-time. However, exposure to smartphone screens, particularly around bedtime, may negatively impact sleep.

How much is left in your "sleep tank"? Proof of concept for a simple model for sleep history feedback.

PubMed

Dorrian, Jillian; Hursh, Steven; Waggoner, Lauren; Grant, Crystal; Pajcin, Maja; Gupta, Charlotte; Coates, Alison; Kennaway, David; Wittert, Gary; Heilbronn, Leonie; Vedova, Chris Della; Banks, Siobhan

2018-02-02

Technology-supported methods for sleep recording are becoming increasingly affordable. Sleep history feedback may help with fatigue-related decision making - Should I drive? Am I fit for work? This study examines a "sleep tank" model (SleepTank ™ ), which is analogous to the fuel tank in a car, refilled by sleep, and depleted during wake. Required inputs are sleep period time and sleep efficiency (provided by many consumer-grade actigraphs). Outputs include suggested hours remaining to "get sleep" and percentage remaining in tank (Tank%). Initial proof of concept analyses were conducted using data from a laboratory-based simulated nightshift study. Ten, healthy males (18-35y) undertook an 8h baseline sleep opportunity and daytime performance testing (BL), followed by four simulated nightshifts (2000 h-0600 h), with daytime sleep opportunities (1000 h-1600 h), then an 8 h night-time sleep opportunity to return to daytime schedule (RTDS), followed by daytime performance testing. Psychomotor Vigilance Task (PVT) and Karolinska Sleepiness Scale were performed at 1200 h on BL and RTDS, and at 1830 h, 2130 h 0000 h and 0400 h each nightshift. A 40-minute York Driving Simulation was performed at 1730 h, 2030 h and 0300 h on each nightshift. Model outputs were calculated using sleep period timing and sleep efficiency (from polysomnography) for each participant. Tank% was a significant predictor of PVT lapses (p < 0.001), and KSS (p < 0.001), such that every 5% reduction resulted in an increase of two lapses, or one point on the KSS. Tank% was also a significant predictor of %time in the Safe Zone from the driving simulator (p = 0.001), such that every 1% increase in the tank resulted in a 0.75% increase in time spent in the Safe Zone. Initial examination of the correspondence between model predictions and performance and sleepiness measures indicated relatively good predictive value. Results provide tentative evidence that this "sleep tank" model may be an informative tool to aid in individual decision-making based on sleep history. Copyright © 2018 Elsevier Ltd. All rights reserved.

The effect of preinjury sleep difficulties on neurocognitive impairment and symptoms after sport-related concussion.

PubMed

Sufrinko, Alicia; Pearce, Kelly; Elbin, R J; Covassin, Tracey; Johnson, Eric; Collins, Michael; Kontos, Anthony P

2015-04-01

Researchers have reported that sleep duration is positively related to baseline neurocognitive performance. However, researchers have yet to examine the effect of preinjury sleep difficulties on postconcussion impairments. To compare neurocognitive impairment and symptoms of athletes with preinjury sleep difficulties to those without after a sport-related concussion (SRC). Cohort study; Level of evidence, 3. The sample included 348 adolescent and adult athletes (age, mean ± SD, 17.43 ± 2.34 years) with a diagnosed SRC. The sample was divided into 2 groups: (1) 34 (10%) participants with preinjury sleep difficulties (sleeping less as well as having trouble falling asleep; SLEEP SX) and (2) 231 (66%) participants without preinjury sleep difficulties (CONTROL). The remaining 84 (24%) participants with minimal sleep difficulties (1 symptom) were excluded. Participants completed the Immediate Postconcussion Assessment and Cognitive Test (ImPACT) and Postconcussion Symptom Scale (PCSS) at baseline and 3 postinjury intervals (2, 5-7, and 10-14 days after injury). A series of repeated-measures analyses of covariance with Bonferroni correction, controlling for baseline non-sleep-related symptoms, were conducted to compare postinjury neurocognitive performance between groups. Follow-up exploratory t tests examined between-group differences at each time interval. A series of analyses of variance were used to examine total PCSS score, sleep-related, and non-sleep-related symptoms across time intervals between groups. Groups differed significantly in PCSS scores across postinjury intervals for reaction time (P < .001), with the preinjury SLEEP SX group performing worse than controls at 5-7 days (mean ± SD, 0.70 ± 0.32 [SLEEP SX], 0.60 ± 0.14 [CONTROL]) and 10-14 days (0.61 ± 0.17 [SLEEP SX]; 0.57 ± 0.10 [CONTROL]) after injury. Groups also differed significantly on verbal memory performance (P = .04), with the SLEEP SX (68.21 ± 18.64) group performing worse than the CONTROL group (76.76 ± 14.50) 2 days after injury. The SLEEP SX group reported higher total symptom (P = .02) and sleep-related symptom (P = .02) scores across postinjury time intervals. Preinjury sleep difficulties may exacerbate neurocognitive impairment and symptoms after concussion. The findings may help clinicians identify athletes who are at risk for worse impairments after a concussion due to preinjury sleep difficulties. © 2015 The Author(s).

Insufficient sleep impairs driving performance and cognitive function.

PubMed

Miyata, Seiko; Noda, Akiko; Ozaki, Norio; Hara, Yuki; Minoshima, Makoto; Iwamoto, Kunihiro; Takahashi, Masahiro; Iidaka, Tetsuya; Koike, Yasuo

2010-01-22

Cumulative sleep deprivation may increase the risk of psychiatric disorders, other disorders, and accidents. We examined the effect of insufficient sleep on cognitive function, driving performance, and cerebral blood flow in 19 healthy adults (mean age 29.2 years). All participants were in bed for 8h (sufficient sleep), and for <4h (insufficient sleep). The oxyhaemoglobin (oxyHb) level by a word fluency task was measured with a near-infrared spectroscopy recorder on the morning following sufficient and insufficient sleep periods. Wisconsin card sorting test, continuous performance test, N-back test, and driving performance were evaluated on the same days. The peak oxyHb level was significantly lower, in the left and right frontal lobes after insufficient sleep than after sufficient sleep (left: 0.25+/-0.13 vs. 0.74+/-0.33 mmol, P<0.001; right: 0.25+/-0.09 vs. 0.69+/-0.44 mmol, P<0.01). The percentage of correct responses on CPT after insufficient sleep was significantly lower than that after sufficient sleep (96.1+/-4.5 vs. 86.6+/-9.8%, P<0.05). The brake reaction time in a harsh-braking test was significantly longer after insufficient sleep than after sufficient sleep (546.2+/-23.0 vs. 478.0+/-51.2 ms, P<0.05). Whereas there were no significant correlations between decrease in oxyHb and the changes of cognitive function or driving performance between insufficient sleep and sufficient sleep. One night of insufficient sleep affects daytime cognitive function and driving performance and this was accompanied by the changes of cortical oxygenation response. (c) 2009 Elsevier Ireland Ltd. All rights reserved.

Digital sleep logs reveal potential impacts of modern temporal structure on class performance in different chronotypes.

PubMed

Smarr, Benjamin Lee

2015-02-01

Stability of sleep and circadian rhythms are important for healthy learning and memory. While experimental manipulations of lifestyle and learning outcomes present major obstacles, the ongoing increase in data sources allows retrospective data mining of people's sleep timing variation. Here I use digital sleep-log data generated by 1109 students in a biology lab course at the University of Washington to test the hypothesis that higher variance in time asleep and later sleep-onset times negatively correlate with class performance, used here as a real-world proxy for learning and memory. I find that sleep duration variance and mean sleep-onset times both significantly correlate with class performance. These correlations are powerful on weeknights but undetectable on Friday and Saturday nights ("free nights"). Finally, although these data come with no demographic information beyond sex, the constructed demographic groups of "larks" and "owls" within the sexes reveal a significant decrease in performance of owls relative to larks in male students, whereas the correlation of performance with sleep-onset time for all male students was only a near-significant trend. This provides a proof of concept that deeper demographic mining of digital logs in the future may identify subgroups for which certain sleep phenotypes have greater predictive value for performance outcomes. The data analyzed are consistent with known patterns, including sleep-timing delays from weeknights to free nights and sleep-timing delays in men relative to women. These findings support the hypothesis that modern schedule impositions on sleep and circadian timing have consequences for real-world learning and memory. This study also highlights the low-cost, large-scale benefits of personal, daily, digital records as an augmentation of sleep and circadian studies. © 2015 The Author(s).

Executive function mediates prospective relationships between sleep duration and sedentary behavior in children.

PubMed

Warren, Christopher; Riggs, Nathaniel; Pentz, Mary Ann

2016-10-01

Childhood sedentary behavior has been linked to increased obesity risk. Prior work has identified associations between sedentary behavior, executive function (EF), and sleep. This study tested the hypothesis that reduced sleep duration may adversely impact EF and lead to increased childhood sedentary behavior. Southern California schoolchildren participating in the school-based health promotion program Pathways to Health (N=709) were assessed annually from 4th through 6th grades (2010-2013) on self-report measures of sedentary behavior, sleep duration, and executive function. A series of path models were specified treating average nightly sleep duration and weekend wake/bed-time shift at 4th grade as predictors of 6th grade sedentary behavior. Four EF subdomains were tested as potential mediators of longitudinal associations at 5th grade. Significant associations between average nightly sleep duration, EF and sedentary behavior were identified (p<0.05), adjusting for participant gender, physical activity, SES, ethnicity, program group assignment, and the presence/absence of parental screen time rules. Fifth grade overall EF (p<0.05)-and in particular the subdomains of inhibitory control (p<0.05) and organization of materials (p<0.01)-significantly mediated the relationship between 4th grade sleep duration and 6th grade sedentary behavior (p<0.05). Furthermore, delay of weekend bed- or wake-times relative to weekdays was prospectively associated with decreased overall EF (p<0.05), but not increased sedentary behavior (p=0.35 for bed-time delay; p=0.64 for wake-time delay), irrespective of average nightly sleep duration. Findings suggest that sleep promotion efforts may reduce children's sedentary behavior both directly and indirectly through changes in EF. Copyright © 2016 Elsevier Inc. All rights reserved.

Executive function mediates prospective relationships between sleep duration and sedentary behavior in children

PubMed Central

Warren, Christopher; Riggs, Nathaniel; Pentz, Mary Ann

2016-01-01

Childhood sedentary behavior has been linked to increased obesity risk. Prior work has identified associations between sedentary behavior, executive function (EF), and sleep. This study tested the hypothesis that reduced sleep duration may adversely impact EF and lead to increased childhood sedentary behavior. Southern California schoolchildren participating in the school-based health promotion program Pathways to Health (N = 709) were assessed annually from 4th through 6th grades (2010–2013) on self-report measures of sedentary behavior, sleep duration, and executive function. A series of path models were specified treating average nightly sleep duration and weekend wake/bed-time shift at 4th grade as predictors of 6th grade sedentary behavior. Four EF subdomains were tested as potential mediators of longitudinal associations at 5th grade. Significant associations between average nightly sleep duration, EF and sedentary behavior were identified (p < 0.05), adjusting for participant gender, physical activity, SES, ethnicity, program group assignment, and the presence/absence of parental screen time rules. Fifth grade overall EF (p < 0.05)—and in particular the subdomains of inhibitory control (p < 0.05) and organization of materials (p < 0.01)—significantly mediated the relationship between 4th grade sleep duration and 6th grade sedentary behavior (p < 0.05). Furthermore, delay of weekend bed- or wake-times relative to weekdays was prospectively associated with decreased overall EF (p < 0.05), but not increased sedentary behavior (p = 0.35 for bed-time delay; p = 0.64 for wake-time delay), irrespective of average nightly sleep duration. Findings suggest that sleep promotion efforts may reduce children’s sedentary behavior both directly and indirectly through changes in EF. PMID:27477059

The impact of sleep loss on the facilitation of seizures: A prospective case-crossover study.

PubMed

Samsonsen, Christian; Sand, Trond; Bråthen, Geir; Helde, Grethe; Brodtkorb, Eylert

2016-11-01

The relationship between sleep and seizures is intricate. The aim of this study was to assess whether sleep loss is an independent seizure precipitant in a clinical setting. In this prospective, observational cross-over study, 179 consecutive hospital admissions for epileptic seizures were included. A semi-structured interview regarding several seizure precipitants was performed. The sleep pattern prior to the seizure, as well as alcohol, caffeine and drug use, were recorded. The interview was repeated by telephone covering the same weekday at a time when there had been no recent seizure. The Hospital Anxiety and Depression Scale (HADS) and a visual analogue scale for perceived stress were applied at admission. Student's t-test, Fisher exact test and ANOVA were used for statistical analyses. Complete data for analysis were retrieved in 144 patients. The sleep-time during the 24h prior to the seizure was lower (7.3h) compared to follow-up (8.3h; p<0.0005). Caffeine consumption and use of relevant non antiepileptic drugs (AED) were not different. HADS and stress scores at admission did not correlate with sleep-time difference. In ANOVA, controlled for alcohol consumption and AED use, the sleep-time difference remained significant (p=0.008). The interaction with alcohol intake was high, but the sleep-time difference remained highly significant also for the non- and low-consumption (≤2 units per day) subgroup (n=121, 7.50h vs 8.42h, p=0.001). Epileptic seizures are often precipitated by a combination of various clinical factors, but sleep loss stands out as an independent seizure trigger. Copyright © 2016 Elsevier B.V. All rights reserved.

Utility of home sleep apnea testing in high-risk veterans.

PubMed

Cairns, Alyssa; Sarmiento, Kathleen; Bogan, Richard

2017-09-01

Many Veterans Affairs Medical Centers (VAMCs) have implemented home sleep apnea testing (HSAT) in lieu of traditional in-lab testing to establish a timely and cost-sensitive diagnosis of obstructive sleep apnea (OSA). However, concern remains for the sensitivity and specificity of said technology in this population as many veterans are at increased risk for many of the comorbid conditions that can limit the accuracy of HSAT results. Hence, the purpose of this study is to evaluate rate of incongruent outcomes (e.g., negative HSAT results despite high clinical symptomology) as well as differences in study quality metrics and predictors of OSA between veteran sleep patients and general sleep patients being evaluated by a home sleep test. A random sample of HSAT outcomes from 1500 veterans and 1500 general sleep clinic patients was retrieved from a repository of anonymized HSAT outcomes from 2009 to 2013. General sleep clinic data were from patients referred for home sleep testing from a variety of clinical practices across North America, whereas VAMC patients were tested using a central dissemination process. All patients were tested for OSA using the Apnea Risk and Evaluation System (ARES), an HSAT that simultaneously records airflow, pulse oximetry, snoring, accelerometry, and EEG. Sample differences and rates of comorbidities, HSAT outcomes, predictors of OSA, and pretest OSA risk information were evaluated between groups. The presence of OSA was defined as an apnea-hypopnea index (AHI; using 4% desaturation criterion) of ≥5 and ≥15 events per hour. Sample differences in predictors of OSA were evaluated using logistic multiple regression. Veterans (91.3% male) were more likely to report comorbidities, especially depression, insomnia, hypertension, diabetes, restless legs syndrome (RLS), and use of sleep and pain medications compared to general sleep clinic patients (57.1% male). Despite differences in the rate of medical comorbidities, no differences were observed between groups with regard to rates of positive studies, study integrity indicators, or predictors of OSA. Veterans, on average, had 30 min less recording time compared to those in the general clinic sample (p < .01). However, these differences did not impact the amount of the record that was deemed valid nor were veterans more likely to have wakefulness after sleep onset. Predictors of OSA for both groups included advancing age, and increased measures of adiposity (neck circumference and BMI). Mean AHI and respiratory disturbance index (RDI) were statistically similar for both groups and were similar for sleep stage and position. Home sleep apnea testing for the diagnosis of OSA appears to yield similar results for VAMC patients deemed at high risk for OSA as it does with general sleep clinic patients.

Association Between Sleep Timing, Obesity, Diabetes: The Hispanic Community Health Study/Study of Latinos (HCHS/SOL) Cohort Study.

PubMed

Knutson, Kristen L; Wu, Donghong; Patel, Sanjay R; Loredo, Jose S; Redline, Susan; Cai, Jianwen; Gallo, Linda C; Mossavar-Rahmani, Yasmin; Ramos, Alberto R; Teng, Yanping; Daviglus, Martha L; Zee, Phyllis C

2017-04-01

Recent studies implicate inadequate sleep duration and quality in metabolic disease. Fewer studies have examined the timing of sleep, which may be important because of its potential impact on circadian rhythms of metabolic function. We examined the association between sleep timing and metabolic risk among Hispanic/Latino adults. Cross-sectional data from community-based study of 13429 participants aged 18-74 years. People taking diabetic medications were excluded. Sleep timing was determined from self-reported bedtimes and wake times. Chronotype was defined as the midpoint of sleep on weekends adjusted for sleep duration on weekdays. Other measurements included body mass index (BMI), fasting glucose levels, estimated insulin resistance (HOMA-IR), glucose levels 2 hours post oral glucose ingestion, and hemoglobin A1c. Survey linear regression models tested associations between sleep timing and metabolic measures. Analyses were stratified by diabetes status and age-group when significant interactions were observed. Among participants with diabetes, fasting glucose levels were positively associated with bedtime (approximately +3%/hour later, p < .01) and midpoint of sleep (approximately +2%/hour later, p < .05). In participants with and without diabetes combined, HOMA-IR was positively associated with midpoint of sleep (+1.5%/hr later, p < .05), and chronotype (+1.2%/hour later, p < .05). Associations differed by age-group. Among those < 36 years, later sleep timing was associated with lower BMI, lower fasting glucose, and lower HbA1c, but the opposite association was observed among older participants. Later sleep timing was associated with higher estimated insulin resistance across all groups. Some associations between sleep timing and metabolic measures may be age-dependent. © Sleep Research Society 2017. Published by Oxford University Press on behalf of the Sleep Research Society. All rights reserved. For permissions, please e-mail journals.permissions@oup.com.

Reduction in time-to-sleep through EEG based brain state detection and audio stimulation.

PubMed

Zhuo Zhang; Cuntai Guan; Ti Eu Chan; Juanhong Yu; Aung Aung Phyo Wai; Chuanchu Wang; Haihong Zhang

2015-08-01

We developed an EEG- and audio-based sleep sensing and enhancing system, called iSleep (interactive Sleep enhancement apparatus). The system adopts a closed-loop approach which optimizes the audio recording selection based on user's sleep status detected through our online EEG computing algorithm. The iSleep prototype comprises two major parts: 1) a sleeping mask integrated with a single channel EEG electrode and amplifier, a pair of stereo earphones and a microcontroller with wireless circuit for control and data streaming; 2) a mobile app to receive EEG signals for online sleep monitoring and audio playback control. In this study we attempt to validate our hypothesis that appropriate audio stimulation in relation to brain state can induce faster onset of sleep and improve the quality of a nap. We conduct experiments on 28 healthy subjects, each undergoing two nap sessions - one with a quiet background and one with our audio-stimulation. We compare the time-to-sleep in both sessions between two groups of subjects, e.g., fast and slow sleep onset groups. The p-value obtained from Wilcoxon Signed Rank Test is 1.22e-04 for slow onset group, which demonstrates that iSleep can significantly reduce the time-to-sleep for people with difficulty in falling sleep.

Sleep Deprivation and Time-Based Prospective Memory.

PubMed

Esposito, Maria José; Occhionero, Miranda; Cicogna, PierCarla

2015-11-01

To evaluate the effect of sleep deprivation on time-based prospective memory performance, that is, realizing delayed intentions at an appropriate time in the future (e.g., to take a medicine in 30 minutes). Between-subjects experimental design. The experimental group underwent 24 h of total sleep deprivation, and the control group had a regular sleep-wake cycle. Participants were tested at 08:00. Laboratory. Fifty healthy young adults (mean age 22 ± 2.1, 31 female). 24 h of total sleep deprivation. Participants were monitored by wrist actigraphy for 3 days before the experimental session. The following cognitive tasks were administered: one time-based prospective memory task and 3 reasoning tasks as ongoing activity. Objective and subjective vigilance was assessed by the psychomotor vigilance task and a visual analog scale, respectively. To measure the time-based prospective memory task we assessed compliance and clock checking behavior (time monitoring). Sleep deprivation negatively affected time-based prospective memory compliance (P < 0.001), objective vigilance (mean RT: P < 0.001; slowest 10% RT: P < 0.001; lapses: P < 0.005), and subjective vigilance (P < 0.0001). Performance on reasoning tasks and time monitoring behavior did not differ between groups. The results highlight the potential dangerous effects of total sleep deprivation on human behavior, particularly the ability to perform an intended action after a few minutes. Sleep deprivation strongly compromises time-based prospective memory compliance but does not affect time check frequency. Sleep deprivation may impair the mechanism that allows the integration of information related to time monitoring with the prospective intention. © 2015 Associated Professional Sleep Societies, LLC.

Sleep restriction can attenuate prioritization benefits on declarative memory consolidation.

PubMed

Lo, June C; Bennion, Kelly A; Chee, Michael W L

2016-12-01

As chronic sleep restriction is a widespread problem among adolescents, the present study investigated the effects of a 1-week sleep restriction (SR) versus control period on the consolidation of long-term memory for prose passages. We also determined whether the benefit of prioritization on memory is modulated by adequate sleep occurring during consolidation. Fifty-six healthy adolescents (25 male, aged 15-19 years) were instructed to remember a prose passage in which half of the content was highlighted (prioritized), and were told that they would receive an additional bonus for remembering highlighted content. Following an initial free recall test, participants underwent a 7-night period in which they received either a 5-h (SR) or 9-h (control) nightly sleep opportunity, monitored by polysomnography on selected nights. Free recall of the passage was tested at the end of the sleep manipulation period (1 week after encoding), and again 6 weeks after encoding. Recall of highlighted content was superior to that of non-highlighted content at all three time-points (initial, 1 week, 6 weeks). This beneficial effect of prioritization on memory was stronger 1 week relative to a few minutes after encoding for the control, but not the SR group. N3 duration was similar in the control and SR groups. Overall, the present study shows that the benefits of prioritization on memory are enhanced over time, requiring time and sleep to unfold fully. Partial sleep deprivation (i.e. 5-h nocturnal sleep opportunity) may attenuate such benefits, but this may be offset by preservation of N3 sleep duration. © 2016 The Authors. Journal of Sleep Research published by John Wiley & Sons Ltd on behalf of European Sleep Research Society.

Meditation acutely improves psychomotor vigilance, and may decrease sleep need

PubMed Central

2010-01-01

Background A number of benefits from meditation have been claimed by those who practice various traditions, but few have been well tested in scientifically controlled studies. Among these claims are improved performance and decreased sleep need. Therefore, in these studies we assess whether meditation leads to an immediate performance improvement on a well validated psychomotor vigilance task (PVT), and second, whether longer bouts of meditation may alter sleep need. Methods The primary study assessed PVT reaction times before and after 40 minute periods of mediation, nap, or a control activity using a within subject cross-over design. This study utilized novice meditators who were current university students (n = 10). Novice meditators completed 40 minutes of meditation, nap, or control activities on six different days (two separate days for each condition), plus one night of total sleep deprivation on a different night, followed by 40 minutes of meditation. A second study examined sleep times in long term experienced meditators (n = 7) vs. non-meditators (n = 23). Experienced meditators and controls were age and sex matched and living in the Delhi region of India at the time of the study. Both groups continued their normal activities while monitoring their sleep and meditation times. Results Novice meditators were tested on the PVT before each activity, 10 minutes after each activity and one hour later. All ten novice meditators improved their PVT reaction times immediately following periods of meditation, and all but one got worse immediately following naps. Sleep deprivation produced a slower baseline reaction time (RT) on the PVT that still improved significantly following a period of meditation. In experiments with long-term experienced meditators, sleep duration was measured using both sleep journals and actigraphy. Sleep duration in these subjects was lower than control non-meditators and general population norms, with no apparent decrements in PVT scores. Conclusions These results suggest that meditation provides at least a short-term performance improvement even in novice meditators. In long term meditators, multiple hours spent in meditation are associated with a significant decrease in total sleep time when compared with age and sex matched controls who did not meditate. Whether meditation can actually replace a portion of sleep or pay-off sleep debt is under further investigation. PMID:20670413

Sleep supports inhibitory operant conditioning memory in Aplysia.

PubMed

Vorster, Albrecht P A; Born, Jan

2017-06-01

Sleep supports memory consolidation as shown in mammals and invertebrates such as bees and Drosophila. Here, we show that sleep's memory function is preserved in Aplysia californica with an even simpler nervous system. Animals performed on an inhibitory conditioning task ("learning that a food is inedible") three times, at Training, Retrieval 1, and Retrieval 2, with 17-h intervals between tests. Compared with Wake animals, remaining awake between Training and Retrieval 1, Sleep animals with undisturbed post-training sleep, performed significantly better at Retrieval 1 and 2. Control experiments testing retrieval only after ∼34 h, confirmed the consolidating effect of sleep occurring within 17 h after training. © 2017 Vorster and Born; Published by Cold Spring Harbor Laboratory Press.

Prioritizing Sleep Health: Public Health Policy Recommendations.

PubMed

Barnes, Christopher M; Drake, Christopher L

2015-11-01

The schedules that Americans live by are not consistent with healthy sleep patterns. In addition, poor access to educational and treatment aids for sleep leaves people engaging in behavior that is harmful to sleep and forgoing treatment for sleep disorders. This has created a sleep crisis that is a public health issue with broad implications for cognitive outcomes, mental health, physical health, work performance, and safety. New public policies should be formulated to address these issues. We draw from the scientific literature to recommend the following: establishing national standards for middle and high school start times that are later in the day, stronger regulation of work hours and schedules, eliminating daylight saving time, educating the public regarding the impact of electronic media on sleep, and improving access to ambulatory in-home diagnostic testing for sleep disorders. © The Author(s) 2015.

Anxiolytic-like effect of Carvacrol (5-isopropyl-2-methylphenol) in mice: involvement with GABAergic transmission.

PubMed

Melo, Francisca Helvira Cavalcante; Venâncio, Edith Teles; de Sousa, Damião Pergentino; de França Fonteles, Marta Maria; de Vasconcelos, Silvânia Maria Mendes; Viana, Glauce Socorro Barros; de Sousa, Francisca Cléa Florenço

2010-08-01

Carvacrol (5-isopropyl-2-methylphenol) is a monoterpenic phenol present in the essencial oil of many plants. It is the major component of the essential oil fraction of oregano and thyme. This work presents the behavioral effects of carvacrol in animal models of elevated plus maze (EPM), open field, Rotarod and barbiturate-induced sleeping time tests in mice. Carvacrol (CVC) was administered orally, in male mice, at single doses of 12.5; 25 and 50 mg/kg while diazepam 1 or 2 mg/kg was used as standard drug and flumazenil (2.5 mg/kg) was used to elucidate the possible anxiolytic mechanism of CVC on the plus maze test. The results showed that CVC, at three doses, had no effect on the spontaneous motor activity in the Rotarod test nor in the number of squares crossed in the open-field test. However, CVC decreased the number of groomings in the open-field test. In the plus maze test, CVC, at three doses significantly increased all the observed parameters in the EPM test and flumazenil was able to reverse the effects of diazepam and CVC. Therefore, CVC did not alter the sleep latency and sleeping time in the barbiturate-induced sleeping time test. These results show that CVC presents anxiolytic effects in the plus maze test which are not influenced by the locomotor activity in the open-field test.

Children benefit differently from night- and day-time sleep in motor learning.

PubMed

Yan, Jin H

2017-08-01

Motor skill acquisition occurs while practicing (on-line) and when asleep or awake (off-line). However, developmental questions still remain about whether children of various ages benefit similarly or differentially from night- and day-time sleeping. The likely circadian effects (time-of-day) and the possible between-test-interference (order effects) associated with children's off-line motor learning are currently unknown. Therefore, this study examines the contributions of over-night sleeping and mid-day napping to procedural skill learning. One hundred and eight children were instructed to practice a finger sequence task using computer keyboards. After an equivalent 11-h interval in one of the three states (sleep, nap, wakefulness), children performed the same sequence in retention tests and a novel sequence in transfer tests. Changes in the movement time and sequence accuracy were evaluated between ages (6-7, 8-9, 10-11years) during practice, and from skill training to retrievals across three states. Results suggest that night-time sleeping and day-time napping improved the tapping speed, especially for the 6-year-olds. The circadian factor did not affect off-line motor learning in children. The interference between the two counter-balanced retrieval tests was not found for the off-line motor learning. This research offers possible evidence about the age-related motor learning characteristics in children and a potential means for enhancing developmental motor skills. The dynamics between age, experience, memory formation, and the theoretical implications of motor skill acquisition are discussed. Copyright © 2017 Elsevier B.V. All rights reserved.

Decision Modeling in Sleep Apnea: The Critical Roles of Pretest Probability, Cost of Untreated Obstructive Sleep Apnea, and Time Horizon

PubMed Central

Moro, Marilyn; Westover, M. Brandon; Kelly, Jessica; Bianchi, Matt T.

2016-01-01

Study Objectives: Obstructive sleep apnea (OSA) is associated with increased morbidity and mortality, and treatment with positive airway pressure (PAP) is cost-effective. However, the optimal diagnostic strategy remains a subject of debate. Prior modeling studies have not consistently supported the widely held assumption that home sleep testing (HST) is cost-effective. Methods: We modeled four strategies: (1) treat no one; (2) treat everyone empirically; (3) treat those testing positive during in-laboratory polysomnography (PSG) via in-laboratory titration; and (4) treat those testing positive during HST with auto-PAP. The population was assumed to lack independent reasons for in-laboratory PSG (such as insomnia, periodic limb movements in sleep, complex apnea). We considered the third-party payer perspective, via both standard (quality-adjusted) and pure cost methods. Results: The preferred strategy depended on three key factors: pretest probability of OSA, cost of untreated OSA, and time horizon. At low prevalence and low cost of untreated OSA, the treat no one strategy was favored, whereas empiric treatment was favored for high prevalence and high cost of untreated OSA. In-laboratory backup for failures in the at-home strategy increased the preference for the at-home strategy. Without laboratory backup in the at-home arm, the in-laboratory strategy was increasingly preferred at longer time horizons. Conclusion: Using a model framework that captures a broad range of clinical possibilities, the optimal diagnostic approach to uncomplicated OSA depends on pretest probability, cost of untreated OSA, and time horizon. Estimating each of these critical factors remains a challenge warranting further investigation. Citation: Moro M, Westover MB, Kelly J, Bianchi MT. Decision modeling in sleep apnea: the critical roles of pretest probability, cost of untreated obstructive sleep apnea, and time horizon. J Clin Sleep Med 2016;12(3):409–418. PMID:26518699

Multiple sleep latency test in narcolepsy type 1 and narcolepsy type 2: A 5-year follow-up study.

PubMed

Huang, Yu-Shu; Guilleminault, Christian; Lin, Cheng-Hui; Chen, Chia-Hsiang; Chin, Wei-Chih; Chen, Tzu-Shuang

2018-05-29

Excessively sleepy teenagers and young adults without sleep-disordered breathing are diagnosed with either narcolepsy type 1 or narcolepsy type 2, or hypersomnia, based on the presence/absence of cataplexy and the results of a multiple sleep latency test. However, there is controversy surrounding this nomenclature. We will try to find the differences between different diagnoses of hypersomnia from the results of the long-term follow-up evaluation of a sleep study. We diagnosed teenagers who had developed excessive daytime sleepiness based on the criteria of the International Classification of Sleep Disorders, 3rd edition. Each individual received the same clinical neurophysiologic testing every year for 5 years after the initial diagnosis of narcolepsy type 1 (n = 111) or type 2 (n = 46). The follow-up evaluation demonstrated that narcolepsy type 1 (narcolepsy-cataplexy) is a well-defined clinical entity, with very reproducible clinical neurophysiologic findings over time, whereas patients with narcolepsy type 2 presented clear clinical and test variability. By the fifth year of the follow-up evaluation, 17.6% of subjects did not meet the diagnostic criteria of narcolepsy type 2, and 23.9% didn't show any two sleep-onset rapid eye movement periods in multiple sleep latency during the 5-year follow-up. Therefore narcolepsy type 1 (narcolepsy-cataplexy) is a well-defined syndrome, with the presentation clearly related to the known consequences of destruction of hypocretin/orexin neurons. Narcolepsy type 2 covers patients with clinical and test variability over time, thus bringing into question the usage of the term "narcolepsy" to label these patients. © 2018 European Sleep Research Society.

Afternoon serum-melatonin in sleep disordered breathing.

PubMed

Ulfberg, J; Micic, S; Strøm, J

1998-08-01

To study afternoon serum-melatonin values in patients with sleep disordered breathing. Melatonin has a strong circadian rhythm with high values during the night-time and low values in the afternoon. Sleep disordered breathing may change the circadian rhythm of melatonin which may have diagnostic implications. The Sleep Laboratory, The Department of Internal Medicine, Avesta Hospital, Sweden, and the Department of Anaesthesiology, Glostrup University Hospital, Copenhagen, Denmark. We examined 60 consecutive patients admitted for sleep disordered breathing and 10 healthy non snoring controls. The patients underwent a sleep apnoea screening test having a specificity of 100% for the obstructive sleep apnoea syndrome (OSAS) using a combination of static charge sensitive bed and oximetry. Obstructive sleep apnoea syndrome was found in 49 patients, eight patients had borderline sleep disordered breathing (BSDB) and three patients were excluded due to interfering disease. Patients and controls had an afternoon determination of serum-melatonin. The Epworth Sleepiness Scale was used to score day-time sleepiness. In comparison with normal controls patients suffering from OSAS had significantly higher serum-melatonin levels in the afternoon. However, as a diagnostic test for OSAS in patients with sleep disordered breathing serum-melatonin showed a low sensitivity but a high specificity. The results indicate that breathing disorders during sleep in general affect pineal function. Sleep disordered breathing seems to disturb pineal function. Determination of afternoon serum-melatonin alone or together with a scoring of daytime sleepiness does not identify OSAS-patients in a heterogeneous population of patients complaining of heavy snoring and excessive daytime sleepiness.

Effects of Sleep Loss on Subjective Complaints and Objective Neurocognitive Performance as Measured by the Immediate Post-Concussion Assessment and Cognitive Testing.

PubMed

Stocker, Ryan P J; Khan, Hassen; Henry, Luke; Germain, Anne

2017-05-01

This study examined the effects of total and partial sleep deprivation on subjective symptoms and objective neurocognitive performance, as measured by the Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT) in a sample of healthy adults. One-hundred and two, right-handed, healthy participants (between ages 18 and 30 years old) completed three consecutive nights in the sleep laboratory with concurrent continuous polysomnography monitoring. Night 1 served as a baseline night. Prior to Night 2, they were randomly assigned to one of three sleep conditions: undisrupted normal sleep (N = 34), sleep restriction (50% of habitual sleep, N = 37), or total sleep deprivation (N = 31). Participants slept undisturbed on Night 3. ImPACT was administered on three separate occasions. Sleep loss was associated with increased severity of subjectively reported affective, cognitive, physical, and sleep symptoms. Although objective neurocognitive task scores derived from the ImPACT battery did not corroborate subjective complaints, sleep loss was associated with significant differences on tasks of visual memory, reaction time, and visual motor speed over time. While self-report measures suggested marked impairments following sleep loss, deficits in neurocognitive performance were observed only on three domains measured with ImPACT. ImPACT may capture subtle changes in neurocognitive performance following sleep loss; however, independent and larger validation studies are needed to determine its sensitivity to acute sleep loss and recovery sleep. Neurocognitive screening batteries may be useful for detecting the effects of more severe or chronic sleep loss under high-stress conditions that mimic high-risk occupations. © The Author 2017. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

An end-to-end framework for real-time automatic sleep stage classification

PubMed Central

Ong, Ju Lynn; Gooley, Joshua J; Ancoli-Israel, Sonia; Chee, Michael W L

2018-01-01

Abstract Sleep staging is a fundamental but time consuming process in any sleep laboratory. To greatly speed up sleep staging without compromising accuracy, we developed a novel framework for performing real-time automatic sleep stage classification. The client–server architecture adopted here provides an end-to-end solution for anonymizing and efficiently transporting polysomnography data from the client to the server and for receiving sleep stages in an interoperable fashion. The framework intelligently partitions the sleep staging task between the client and server in a way that multiple low-end clients can work with one server, and can be deployed both locally as well as over the cloud. The framework was tested on four datasets comprising ≈1700 polysomnography records (≈12000 hr of recordings) collected from adolescents, young, and old adults, involving healthy persons as well as those with medical conditions. We used two independent validation datasets: one comprising patients from a sleep disorders clinic and the other incorporating patients with Parkinson’s disease. Using this system, an entire night’s sleep was staged with an accuracy on par with expert human scorers but much faster (≈5 s compared with 30–60 min). To illustrate the utility of such real-time sleep staging, we used it to facilitate the automatic delivery of acoustic stimuli at targeted phase of slow-sleep oscillations to enhance slow-wave sleep. PMID:29590492

Continuous positive airway pressure improves sleep and daytime sleepiness in patients with Parkinson disease and sleep apnea.

PubMed

Neikrug, Ariel B; Liu, Lianqi; Avanzino, Julie A; Maglione, Jeanne E; Natarajan, Loki; Bradley, Lenette; Maugeri, Alex; Corey-Bloom, Jody; Palmer, Barton W; Loredo, Jose S; Ancoli-Israel, Sonia

2014-01-01

Obstructive sleep apnea (OSA), common in Parkinson disease (PD), contributes to sleep disturbances and daytime sleepiness. We assessed the effect of continuous positive airway pressure (CPAP) on OSA, sleep, and daytime sleepiness in patients with PD. This was a randomized placebo-controlled, crossover design. Patients with PD and OSA were randomized into 6 w of therapeutic treatment or 3 w of placebo followed by 3 w of therapeutic treatment. Patients were evaluated by polysomnography (PSG) and multiple sleep latency test (MSLT) pretreatment (baseline), after 3 w, and after 6 w of CPAP treatment. Analyses included mixed models, paired analysis, and within-group analyses comparing 3 w to 6 w of treatment. Sleep laboratory. Thirty-eight patients with PD (mean age = 67.2 ± 9.2 y; 12 females). Continuous positive airway pressure. PSG OUTCOME MEASURES: sleep efficiency, %sleep stages (N1, N2, N3, R), arousal index, apnea-hypopnea index (AHI), and % time oxygen saturation < 90% (%time SaO2 < 90%). MSLT outcome measures: mean sleep-onset latency (MSL). There were significant group-by-time interactions for AHI (P < 0.001), % time SaO2 < 90% (P = 0.02), %N2 (P = 0.015) and %N3 (P = 0.014). Subjects receiving therapeutic CPAP showed significant decrease in AHI, %time SaO2 < 90%, %N2, and significant increase in %N3 indicating effectiveness of CPAP in the treatment of OSA, improvement in nighttime oxygenation, and in deepening sleep. The paired sample analyses revealed that 3 w of therapeutic treatment resulted in significant decreases in arousal index (t = 3.4, P = 0.002). All improvements after 3 w were maintained at 6 w. Finally, 3 w of therapeutic CPAP also resulted in overall decreases in daytime sleepiness (P = 0.011). Therapeutic continuous positive airway pressure versus placebo was effective in reducing apnea events, improving oxygen saturation, and deepening sleep in patients with Parkinson disease and obstructive sleep apnea. Additionally, arousal index was reduced and effects were maintained at 6 weeks. Finally, 3 weeks of continuous positive airway pressure treatment resulted in reduced daytime sleepiness measured by multiple sleep latency test. These results emphasize the importance of identifying and treating obstructive sleep apnea in patients with Parkinson disease.

Nocturnal Sleep Dynamics Identify Narcolepsy Type 1

PubMed Central

Pizza, Fabio; Vandi, Stefano; Iloti, Martina; Franceschini, Christian; Liguori, Rocco; Mignot, Emmanuel; Plazzi, Giuseppe

2015-01-01

Study Objectives: To evaluate the reliability of nocturnal sleep dynamics in the differential diagnosis of central disorders of hypersomnolence. Design: Cross-sectional. Setting: Sleep laboratory. Patients: One hundred seventy-five patients with hypocretin-deficient narcolepsy type 1 (NT1, n = 79), narcolepsy type 2 (NT2, n = 22), idiopathic hypersomnia (IH, n = 22), and “subjective” hypersomnolence (sHS, n = 52). Interventions: None. Methods: Polysomnographic (PSG) work-up included 48 h of continuous PSG recording. From nocturnal PSG conventional sleep macrostructure, occurrence of sleep onset rapid eye movement period (SOREMP), sleep stages distribution, and sleep stage transitions were calculated. Patient groups were compared, and receiver operating characteristic (ROC) curve analysis was used to test the diagnostic utility of nocturnal PSG data to identify NT1. Results: Sleep macrostructure was substantially stable in the 2 nights of each diagnostic group. NT1 and NT2 patients had lower latency to rapid eye movement (REM) sleep, and NT1 patients showed the highest number of awakenings, sleep stage transitions, and more time spent in N1 sleep, as well as most SOREMPs at daytime PSG and at multiple sleep latency test (MSLT) than all other groups. ROC curve analysis showed that nocturnal SOREMP (area under the curve of 0.724 ± 0.041, P < 0.0001), percent of total sleep time spent in N1 (0.896 ± 0.023, P < 0.0001), and the wakefulness-sleep transition index (0.796 ± 0.034, P < 0.0001) had a good sensitivity and specificity profile to identify NT1 sleep, especially when used in combination (0.903 ± 0.023, P < 0.0001), similarly to SOREMP number at continuous daytime PSG (0.899 ± 0.026, P < 0.0001) and at MSLT (0.956 ± 0.015, P < 0.0001). Conclusions: Sleep macrostructure (i.e. SOREMP, N1 timing) including stage transitions reliably identifies hypocretin-deficient narcolepsy type 1 among central disorders of hypersomnolence. Citation: Pizza F, Vandi S, Iloti M, Franceschini C, Liguori R, Mignot E, Plazzi G. Nocturnal sleep dynamics identify narcolepsy type 1. SLEEP 2015;38(8):1277–1284. PMID:25845690

Validation of Sleep-Tracking Technology Compared with Polysomnography in Adolescents

PubMed Central

de Zambotti, Massimiliano; Baker, Fiona C.; Colrain, Ian M.

2015-01-01

Study Objectives: To evaluate the accuracy in measuring nighttime sleep of a fitness tracker (Jawbone UP) compared to polysomnography (PSG). Design: Jawbone UP and PSG data were simultaneously collected from adolescents during an overnight laboratory recording. Agreements between Jawbone UP and PSG sleep outcomes were analyzed using paired t tests and Bland-Altman plots. Multiple regressions were used to investigate which PSG sleep measures predicted Jawbone UP “Sound sleep” and “Light sleep.” Setting: SRI International Human Sleep Laboratory. Participants: Sixty-five healthy adolescents (28 females, mean age ± standard deviation [SD]: 15.8 ± 2.5 y). Interventions: N/A. Measurements and Results: Outcomes showed good agreements between Jawbone UP and PSG for total sleep time (mean differences ± SD: −10.0 ± 20.5 min), sleep efficiency (mean differences ± SD: −1.9 ± 4.2 %), and wake after sleep onset (WASO) (mean differences ± SD: 10.6 ± 14.7 min). Overall, Jawbone UP overestimated PSG total sleep time and sleep efficiency and underestimated WASO but differences were small and, on average, did not exceed clinically meaningful cutoffs of > 30 min for total sleep time and > 5% for sleep efficiency. Multiple regression models showed that Jawbone UP “Sound sleep” measure was predicted by PSG time in N2 (β = 0.25), time in rapid eye movement (β = 0.29), and arousal index (β = −0.34). Jawbone UP “Light sleep” measure was predicted by PSG time in N2 (β = 0.48), time in N3 (β = 0.49), arousal index (β = 0.38) and awakening index (β = 0.28). Jawbone UP showed a progression from slight overestimation to underestimation of total sleep time and sleep efficiency with advancing age. All relationships were similar in boys and girls. Conclusions: Jawbone UP shows good agreement with polysomnography in measures of total sleep time and wake after sleep onset in adolescent boys and girls. Further validation is needed in other age groups and clinical populations before advocating use of these inexpensive and easy-to-use devices in clinical sleep medicine and research. Citation: de Zambotti M, Baker FC, Colrain IM. Validation of sleep-tracking technology compared with polysomnography in adolescents. SLEEP 2015;38(9):1461–1468. PMID:26158896

The role of a short post-lunch nap in improving cognitive, motor, and sprint performance in participants with partial sleep deprivation.

PubMed

Waterhouse, J; Atkinson, G; Edwards, B; Reilly, T

2007-12-01

The aim of this study was to determine the effects of a post-lunch nap on subjective alertness and performance following partial sleep loss. Ten healthy males (mean age 23.3 years, s = 3.4) either napped or sat quietly from 13:00 to 13:30 h after a night of shortened sleep (sleep 23:00-03:00 h only). Thirty minutes after the afternoon nap or control (no-nap) condition, alertness, short-term memory, intra-aural temperature, heart rate, choice reaction time, grip strength, and times for 2-m and 20-m sprints were recorded. The afternoon nap lowered heart rate and intra-aural temperature. Alertness, sleepiness, short-term memory, and accuracy at the 8-choice reaction time test were improved by napping (P < 0.05), but mean reaction times and grip strength were not affected (P > 0.05). Sprint times were improved. Mean time for the 2-m sprints fell from 1.060 s (s(x) = 0.018) to 1.019 s (s(x) = 0.019) (P = 0.031 paired t-test); mean time for the 20-m sprints fell from 3.971 s (s(x) = 0.054) to 3.878 s (s(x) = 0.047) (P = 0.013). These results indicate that a post-lunch nap improves alertness and aspects of mental and physical performance following partial sleep loss, and have implications for athletes with restricted sleep during training or before competition.

Acute Effects of 24-h Sleep Deprivation on Salivary Cortisol and Testosterone Concentrations and Testosterone to Cortisol Ratio Following Supplementation with Caffeine or Placebo

PubMed Central

DONALD, CIARAN MC; MOORE, JOSS; MCINTYRE, ALAN; CARMODY, KEVIN; DONNE, BERNARD

2017-01-01

Caffeine has become a popular ergogenic aid amongst athletes and usage to improve athletic performance has been well documented. The effect of caffeine on anabolic and catabolic hormones in a sleep-deprived s tate has had little investigation to date. The purpose of the current study was to investigate the potential of caffeine to offset the effects, if any, of short-term sleep deprivation and exercise on an athlete’s testosterone and cortisol concentrations via salivary technique. Eleven competitive male athletes volunteered to be part of this prospective double-blinded study. Three test days were scheduled for each athlete; one non-sleep deprived, one sleep-deprived with caffeine supplementation (6 mg.kg−1) and one sleep-deprived with placebo ingestion. Sleep deprivation was defined as 24-h without sleep. Each test day was composed of 2 aerobic components: a modified Hoff test and a Yo-Yo test. Testosterone and cortisol concentrations were measured via salivary analysis at 4 different time-points; T1 to T4, representing baseline, and pre- and post-aerobic components, respectively. Overall no significant differences were detected comparing the different sleep states for testosterone or cortisol concentrations. A trend existed whereby the sleep-deprived with caffeine ingestion state mirrored the non-sleep deprived state for cortisol concentration. Therefore, caffeine supplementation may have potential benefits for athletes during short-term aerobic exercise when sleep-deprived. An increase in mean testosterone concentration post-aerobic exercise was only observed in the sleep-deprived with caffeine ingestion state. PMID:28479951

Direct Measurements of Smartphone Screen-Time: Relationships with Demographics and Sleep

PubMed Central

Christensen, Matthew A.; Bettencourt, Laura; Kaye, Leanne; Moturu, Sai T.; Nguyen, Kaylin T.; Olgin, Jeffrey E.; Pletcher, Mark J.; Marcus, Gregory M.

2016-01-01

Background Smartphones are increasingly integrated into everyday life, but frequency of use has not yet been objectively measured and compared to demographics, health information, and in particular, sleep quality. Aims The aim of this study was to characterize smartphone use by measuring screen-time directly, determine factors that are associated with increased screen-time, and to test the hypothesis that increased screen-time is associated with poor sleep. Methods We performed a cross-sectional analysis in a subset of 653 participants enrolled in the Health eHeart Study, an internet-based longitudinal cohort study open to any interested adult (≥ 18 years). Smartphone screen-time (the number of minutes in each hour the screen was on) was measured continuously via smartphone application. For each participant, total and average screen-time were computed over 30-day windows. Average screen-time specifically during self-reported bedtime hours and sleeping period was also computed. Demographics, medical information, and sleep habits (Pittsburgh Sleep Quality Index–PSQI) were obtained by survey. Linear regression was used to obtain effect estimates. Results Total screen-time over 30 days was a median 38.4 hours (IQR 21.4 to 61.3) and average screen-time over 30 days was a median 3.7 minutes per hour (IQR 2.2 to 5.5). Younger age, self-reported race/ethnicity of Black and "Other" were associated with longer average screen-time after adjustment for potential confounders. Longer average screen-time was associated with shorter sleep duration and worse sleep-efficiency. Longer average screen-times during bedtime and the sleeping period were associated with poor sleep quality, decreased sleep efficiency, and longer sleep onset latency. Conclusions These findings on actual smartphone screen-time build upon prior work based on self-report and confirm that adults spend a substantial amount of time using their smartphones. Screen-time differs across age and race, but is similar across socio-economic strata suggesting that cultural factors may drive smartphone use. Screen-time is associated with poor sleep. These findings cannot support conclusions on causation. Effect-cause remains a possibility: poor sleep may lead to increased screen-time. However, exposure to smartphone screens, particularly around bedtime, may negatively impact sleep. PMID:27829040

Prior sleep with zolpidem enhances the effect of caffeine or modafinil during 18 hours continuous work.

PubMed

Batéjat, Denise; Coste, Olivier; Van Beers, Pascal; Lagarde, Didier; Piérard, Christophe; Beaumont, Maurice

2006-05-01

Continuous military operations may disrupt sleep-wakefulness cycles, resulting in impaired performance and fatigue. We assessed the treatment efficacy of a hypnotic-psychostimulant combination to maintain sleep quality, performance, and alertness during a 42-h simulated military operation. A 6-h prophylactic sleep period with zolpidem (ZOL) followed by a 18-h continuous work period with administration at midway of 300 mg of slow release caffeine (CAF) or 200 mg of modafinil (MOD) was performed by eight healthy male subjects. Performance level was assessed with a reaction time test, a memory search test, a dual task, an attention test, and a computerized Stroop test. Cortical activation level was evaluated by the Critical Flicker Frequency test. Subjective sleepiness was evaluated using a visual analog scale and questionnaires. Effects of drugs on prophylactic and recovery sleep were also quantified from EEG recordings. CAF and MOD maintained performance and alertness throughout the 18-h work period. As shown by EEG recordings, ZOL improved prophylactic sleep without any deleterious effect on performance immediately after waking. As a result of its positive effects on prophylactic sleep, a lower pressure for slow wave sleep during recovery sleep was observed; nevertheless, zolpidem did not enhance the effects of either psychostimulant on performance. MOD and CAF may be of value in promoting performance and wakefulness during shiftwork or military operations while zolpidem improves prophylactic sleep quality without any deleterious effect after waking. We concluded that a zolpidem/ caffeine or modafinil combination could be useful in a context of environmental conditions not conducive to sleep.

Sensitivity and Validity of Psychometric Tests for Assessing Driving Impairment: Effects of Sleep Deprivation

PubMed Central

Jongen, Stefan; Perrier, Joy; Vuurman, Eric F.; Ramaekers, Johannes G.; Vermeeren, Annemiek

2015-01-01

Objective To assess drug induced driving impairment, initial screening is needed. However, no consensus has been reached about which initial screening tools have to be used. The present study aims to determine the ability of a battery of psychometric tests to detect performance impairing effects of clinically relevant levels of drowsiness as induced by one night of sleep deprivation. Methods Twenty four healthy volunteers participated in a 2-period crossover study in which the highway driving test was conducted twice: once after normal sleep and once after one night of sleep deprivation. The psychometric tests were conducted on 4 occasions: once after normal sleep (at 11 am) and three times during a single night of sleep deprivation (at 1 am, 5 am, and 11 am). Results On-the-road driving performance was significantly impaired after sleep deprivation, as measured by an increase in Standard Deviation of Lateral Position (SDLP) of 3.1 cm compared to performance after a normal night of sleep. At 5 am, performance in most psychometric tests showed significant impairment. As expected, largest effect sizes were found on performance in the Psychomotor Vigilance Test (PVT). Large effects sizes were also found in the Divided Attention Test (DAT), the Attention Network Test (ANT), and the test for Useful Field of View (UFOV) at 5 and 11 am during sleep deprivation. Effects of sleep deprivation on SDLP correlated significantly with performance changes in the PVT and the DAT, but not with performance changes in the UFOV. Conclusion From the psychometric tests used in this study, the PVT and DAT seem most promising for initial evaluation of drug impairment based on sensitivity and correlations with driving impairment. Further studies are needed to assess the sensitivity and validity of these psychometric tests after benchmark sedative drug use. PMID:25668292

Effects of three hypnotics on the sleep-wakefulness cycle in sleep-disturbed rats.

PubMed

Shinomiya, Kazuaki; Shigemoto, Yuki; Omichi, Junji; Utsu, Yoshiaki; Mio, Mitsunobu; Kamei, Chiaki

2004-04-01

New sleep disturbance model in rats is useful for estimating the characteristics of some hypnotics. The present study was undertaken to investigate the utility of a sleep disturbance model by placing rats on a grid suspended over water using three kinds of hypnotics, that is, short-acting benzodiazepine (triazolam), intermediate-acting benzodiazepine (flunitrazepam) and long-acting barbiturate (phenobarbital). Electrodes for measurement of EEG and EMG were implanted into the frontal cortex and the dorsal neck muscle of rats. EEG and EMG were recorded with an electroencephalogram. SleepSign ver.2.0 was used for EEG and EMG analysis. Total times of wakefulness, non-REM and REM sleep were measured from 0900 to 1500 hours. In rats placed on the grid suspended over water up to 1 cm under the grid surface, not only triazolam but also flunitrazepam and phenobarbital caused a shortening of sleep latency. Both flunitrazepam and phenobarbital were effective in increasing of total non-REM sleep time in rats placed on sawdust or the grid, and the effects of both drugs in rats placed on the grid were larger than those in rats placed on sawdust. Measurement of the hourly non-REM sleep time was useful for investigating the peak time and duration of effect of the three hypnotics. Phenobarbital showed a decrease in total REM sleep time in rats placed on the grid, although both triazolam and flunitrazepam were without effect. The present insomnia model can be used as a sleep disturbance model for testing not only the sleep-inducing effects but also the sleep-maintaining effects including non-REM sleep and REM sleep of hypnotics.

Effects of suvorexant, an orexin receptor antagonist, on sleep parameters as measured by polysomnography in healthy men.

PubMed

Sun, Hong; Kennedy, William P; Wilbraham, Darren; Lewis, Nicole; Calder, Nicole; Li, Xiaodong; Ma, Junshui; Yee, Ka Lai; Ermlich, Susan; Mangin, Eric; Lines, Christopher; Rosen, Laura; Chodakewitz, Jeffrey; Murphy, Gail M

2013-02-01

Suvorexant (MK-4305) is an orexin receptor antagonist being developed for the treatment of insomnia. This report describes the effects of nighttime administration of suvorexant on polysomnography (PSG) sleep parameters in healthy young men. Randomized, double-blind, placebo-controlled, 4-period crossover PSG study, followed by an additional 5(th) period to assess pharmacokinetics. Sleep laboratory. Healthy young men between 18 and 45 years of age (22 enrolled, 19 completed). Periods 1-4: suvorexant (10 mg, 50 mg, or 100 mg) or placebo 1 h before nighttime PSG recording. Period 5: suvorexant 10 mg, 50 mg, or 100 mg. In Periods 1-4, overnight sleep parameters were recorded by PSG and next-morning residual effects were assessed by psychomotor performance tests and subjective assessments. Statistically significant sleep-promoting effects were observed with all doses of suvorexant compared to placebo. Suvorexant 50 mg and 100 mg significantly decreased latency to persistent sleep and wake after sleep onset time, and increased sleep efficiency. Suvorexant 10 mg significantly decreased wake after sleep onset time. There were no statistically significant effects of suvorexant on EEG frequency bands including delta (slow wave) activity based on power spectral analysis. Suvorexant was well tolerated. There was no evidence of next-day residual effects for suvorexant 10 mg. Suvorexant 50 mg statistically significantly reduced subjective alertness, and suvorexant 100 mg significantly increased reaction time and reduced subjective alertness. There were no statistically significant effects of any suvorexant dose on digit symbol substitution test performance. In Period 5, plasma samples of suvorexant were collected for pharmacokinetic evaluation. The median T(max) was 3 hours and apparent terminal t(½) was 9-13 hours. In healthy young men without sleep disorders, suvorexant promoted sleep with some evidence of residual effects at the highest doses.

Sleep pattern and locomotor activity are impaired by doxorubicin in non-tumor-bearing rats.

PubMed

Lira, Fabio Santos; Esteves, Andrea Maculano; Pimentel, Gustavo Duarte; Rosa, José Cesar; Frank, Miriam Kannebley; Mariano, Melise Oliveira; Budni, Josiane; Quevedo, João; Santos, Ronaldo Vagner Dos; de Mello, Marco Túlio

2016-01-01

We sought explore the effects of doxorubicin on sleep patterns and locomotor activity. To investigate these effects, two groups were formed: a control group and a Doxorubicin (DOXO) group. Sixteen rats were randomly assigned to either the control or DOXO groups. The sleep patterns were examined by polysomnographic recording and locomotor activity was evaluated in an open-field test. In the light period, the total sleep time and slow wave sleep were decreased, while the wake after sleep onset and arousal were increased in the DOXO group compared with the control group (p<0.05). In the dark period, the total sleep time, arousal, and slow wave sleep were increased, while the wake after sleep onset was decreased in the DOXO group compared with the control group (p<0.05). Moreover, DOXO induced a decrease of crossing and rearing numbers when compared control group (p<0.05). Therefore, our results suggest that doxorubicin induces sleep pattern impairments and reduction of locomotor activity.

Sleep can reduce the testing effect: it enhances recall of restudied items but can leave recall of retrieved items unaffected.

PubMed

Bäuml, Karl-Heinz T; Holterman, Christoph; Abel, Magdalena

2014-11-01

The testing effect refers to the finding that retrieval practice in comparison to restudy of previously encoded contents can improve memory performance and reduce time-dependent forgetting. Naturally, long retention intervals include both wake and sleep delay, which can influence memory contents differently. In fact, sleep immediately after encoding can induce a mnemonic benefit, stabilizing and strengthening the encoded contents. We investigated in a series of 5 experiments whether sleep influences the testing effect. After initial study of categorized item material (Experiments 1, 2, and 4A), paired associates (Experiment 3), or educational text material (Experiment 4B), subjects were asked to restudy encoded contents or engage in active retrieval practice. A final recall test was conducted after a 12-hr delay that included diurnal wakefulness or nocturnal sleep. The results consistently showed typical testing effects after the wake delay. However, these testing effects were reduced or even eliminated after sleep, because sleep benefited recall of restudied items but left recall of retrieved items unaffected. The findings are consistent with the bifurcation model of the testing effect (Kornell, Bjork, & Garcia, 2011), according to which the distribution of memory strengths across items is shifted differentially by retrieving and restudying, with retrieval strengthening items to a much higher degree than restudy does. On the basis of this model, most of the retrieved items already fall above recall threshold in the absence of sleep, so additional sleep-induced strengthening may not improve recall of retrieved items any further. PsycINFO Database Record (c) 2014 APA, all rights reserved.

Reliability of Sleep Measures from Four Personal Health Monitoring Devices Compared to Research-Based Actigraphy and Polysomnography.

PubMed

Mantua, Janna; Gravel, Nickolas; Spencer, Rebecca M C

2016-05-05

Polysomnography (PSG) is the "gold standard" for monitoring sleep. Alternatives to PSG are of interest for clinical, research, and personal use. Wrist-worn actigraph devices have been utilized in research settings for measures of sleep for over two decades. Whether sleep measures from commercially available devices are similarly valid is unknown. We sought to determine the validity of five wearable devices: Basis Health Tracker, Misfit Shine, Fitbit Flex, Withings Pulse O2, and a research-based actigraph, Actiwatch Spectrum. We used Wilcoxon Signed Rank tests to assess differences between devices relative to PSG and correlational analysis to assess the strength of the relationship. Data loss was greatest for Fitbit and Misfit. For all devices, we found no difference and strong correlation of total sleep time with PSG. Sleep efficiency differed from PSG for Withings, Misfit, Fitbit, and Basis, while Actiwatch mean values did not differ from that of PSG. Only mean values of sleep efficiency (time asleep/time in bed) from Actiwatch correlated with PSG, yet this correlation was weak. Light sleep time differed from PSG (nREM1 + nREM2) for all devices. Measures of Deep sleep time did not differ from PSG (SWS + REM) for Basis. These results reveal the current strengths and limitations in sleep estimates produced by personal health monitoring devices and point to a need for future development.

Melatonin ingestion after exhaustive late-evening exercise improves sleep quality and quantity, and short-term performances in teenage athletes.

PubMed

Cheikh, Mohamed; Hammouda, Omar; Gaamouri, Nawel; Driss, Tarak; Chamari, Karim; Cheikh, Ridha Ben; Dogui, Mohamed; Souissi, Nizar

2018-05-30

The present study aimed to explore the effects of a single 10-mg dose of melatonin (MEL) administration after exhaustive late-evening exercise on sleep quality and quantity, and short-term physical and cognitive performances in healthy teenagers. Ten male adolescent athletes (mean ± SD, age = 15.4 ± 0.3 years, body-mass = 60.68 ± 5.7 kg, height = 167.9 ± 6.9 cm and BMI = 21.21 ± 2.5) performed two test sessions separated by at least one week. During each session, participants completed the Yo-Yo intermittent-recovery-test level-1 (YYIRT-1) at ~20:00 h. Then, sleep polysomnography was recorded from 22:15 min to 07:00 h, after a double blind randomized order administration of a single 10-mg tablet of MEL (MEL-10 mg) or Placebo (PLA). The following morning, Hooper wellness index was administered and the participants performed the Choice Reaction Time (CRT) test, the Zazzo test and some short-term physical exercises (YYIRT-1, vertical and horizontal Jumps (VJ; HJ), Hand grip strength (HG), and five-jump test (5-JT)). Evening total distance covered in the YYIRT-1 did not change during the two conditions (p > 0.05). Total sleep time (Δ = 24.55 mn; p < 0.001), sleep efficiency (Δ = 4.47%; p < 0.001), stage-3 sleep (N3 sleep) (Δ = 1.73%; p < 0.05) and rapid-eye-movement sleep (Δ = 2.15%; p < 0.001) were significantly higher with MEL in comparison with PLA. Moreover, sleep-onset-latency (Δ = -8.45mn; p < 0.001), total time of nocturnal awakenings after sleep-onset (NA) (Δ = -11 mn; p < 0.001), stage-1 sleep (N1 sleep) (Δ = -1.7%; p < 0.001) and stage-2 sleep (N2 sleep) (Δ = -1.9%; p < 0.05) durations were lower with MEL. The Hooper index showed a better subjective sleep quality, a decrease of the subjective perception of fatigue and a reduced level of muscle soreness with MEL. Moreover, MEL improved speed and performance but not inaccuracy during the Zazzo test. CRT was faster with MEL. Morning YYIRT-1 (Δ = 82 m; p < 0.001) and 5-JT (Δ = 0.08 m; p < 0.05) performances were significantly higher with MEL in comparison with PLA. In contrast, HG, VJ and HJ performances did not change during the two conditions (p > 0.05). The administration of a single dose of MEL-10 mg after strenuous late-evening exercise improved sleep quality and quantity, selective attention, subjective assessment of the general wellness state, and some short-term physical performances the following morning in healthy teenagers.

Sleep schedules and school performance in Indigenous Australian children.

PubMed

Blunden, Sarah; Magee, Chris; Attard, Kelly; Clarkson, Larissa; Caputi, Peter; Skinner, Timothy

2018-04-01

Sleep duration and sleep schedule variability have been related to negative health and well-being outcomes in children, but little is known about Australian Indigenous children. Data for children aged 7-9 years came from the Australian Longitudinal Study of Indigenous Children and the National Assessment Program-Literacy and Numeracy (NAPLAN). Latent class analysis determined sleep classes taking into account sleep duration, bedtimes, waketimes, and variability in bedtimes from weekdays to weekends. Regression models tested whether the sleep classes were cross-sectionally associated with grade 3 NAPLAN scores. Latent change score modeling then examined whether the sleep classes predicted changes in NAPLAN performance from grades 3 to 5. Five sleep schedule classes were identified: normative sleep, early risers, long sleep, variable sleep, and short sleep. Overall, long sleepers performed best, with those with reduced sleep (short sleepers and early risers) performing the worse on grammar, numeracy, and writing performance. Latent change score results also showed that long sleepers performed best in spelling and writing and short sleepers and typical sleepers performed the worst over time. In this sample of Australian Indigenous children, short sleep was associated with poorer school performance compared with long sleep, with this performance worsening over time for some performance indicators. Other sleep schedules (eg, early wake times and variable sleep) also had some relationships with school performance. As sleep scheduling is modifiable, this offers opportunity for improvement in sleep and thus performance outcomes for these and potentially all children. Copyright © 2018 National Sleep Foundation. Published by Elsevier Inc. All rights reserved.

Objective but not subjective sleep predicts memory in community-dwelling older adults.

PubMed

Cavuoto, Marina G; Ong, Ben; Pike, Kerryn E; Nicholas, Christian L; Bei, Bei; Kinsella, Glynda J

2016-08-01

Research on the relationship between habitual sleep patterns and memory performance in older adults is limited. No previous study has used objective and subjective memory measures in a large, older-aged sample to examine the association between sleep and various domains of memory. The aim of this study was to examine the association between objective and subjective measures of sleep with memory performance in older adults, controlling for the effects of potential confounds. One-hundred and seventy-three community-dwelling older adults aged 65-89 years in Victoria, Australia completed the study. Objective sleep quality and length were ascertained using the Actiwatch 2 Mini-Mitter, while subjective sleep was measured using the Pittsburgh Sleep Quality Index. Memory was indexed by tests of retrospective memory (Hopkins Verbal Learning Test - Revised), working memory (n-back, 2-back accuracy) and prospective memory (a habitual button pressing task). Compared with normative data, overall performance on retrospective memory function was within the average range. Hierarchical regression was used to determine whether objective or subjective measures of sleep predicted memory performances after controlling for demographics, health and mood. After controlling for confounds, actigraphic sleep indices (greater wake after sleep onset, longer sleep-onset latency and longer total sleep time) predicted poorer retrospective (∆R(2)  = 0.05, P = 0.016) and working memory (∆R(2)  = 0.05, P = 0.047). In contrast, subjective sleep indices did not significantly predict memory performances. In community-based older adults, objectively-measured, habitual sleep indices predict poorer memory performances. It will be important to follow the sample longitudinally to determine trajectories of change over time. © 2016 European Sleep Research Society.

Daytime Sleepiness Increases With Age in Early Adolescence: A Sleep Restriction Dose-Response Study.

PubMed

Campbell, Ian G; Burright, Christopher S; Kraus, Amanda M; Grimm, Kevin J; Feinberg, Irwin

2017-05-01

Daytime sleepiness increases across adolescence. This increase is commonly attributed to insufficient sleep durations resulting from increasingly limited time in bed. We tested the effects of 3 sleep schedules on daytime sleepiness and whether these effects changed with age in early adolescence. In 77 children ranging in age from 9.9 to 14 years, objective (multiple sleep latency test [MSLT]) and subjective (Karolinska sleepiness scale [KSS]) sleepiness was measured following 4 consecutive nights of either 7, 8.5, or 10 hours in bed. All participants completed all 3 sleep schedules. The order in which they completed the schedules was not randomized but was accounted for in all statistical analyses. Time in bed restriction decreased sleep duration and increased objective and subjective daytime sleepiness. Although the sleep durations did not change with age, the likelihood of falling asleep during the MSLT increased with age. Nevertheless, sleep restriction produced a greater increase in MSLT-measured sleepiness in younger participants. Subjective sleepiness measured with the KSS increased with shorter sleep duration, but this effect did not change with age. Increasing objective daytime sleepiness in early adolescence cannot simply be attributed to reduced sleep due to restricted sleep schedules. We propose that some of the increased daytime sleepiness of adolescents is a consequence of adolescent brain reorganization driven by synaptic pruning which decreases the intensity of waking brain activity. © Sleep Research Society 2017. Published by Oxford University Press on behalf of the Sleep Research Society. All rights reserved. For permissions, please e-mail journals.permissions@oup.com.

Flight crew sleep during multiple layover polar flights.

PubMed

Sasaki, M; Kurosaki, Y S; Spinweber, C L; Graeber, R C; Takahashi, T

1993-07-01

This study investigated changes in sleep after multiple transmeridian flights. The subjects were 12 B747 airline pilots operating on the following polar flight: Tokyo (TYO)-Anchorage (ANC)-London (LON)-Anchorage-Tokyo. Sleep polysomnograms were recorded on two baseline nights (B1, B2), during layovers, and, after returning to Tokyo, two recovery nights were recorded (R1, R2). In ANC (outbound), total sleep time (TST) was reduced and, sleep efficiency was low (72.0%). In London, time in bed (TIB) increased slightly, but sleep efficiency was still reduced. On return to ANC (inbound), there was considerable slow wave sleep (SWS) rebound and multiple awakenings reduced sleep efficiency to 76.8%. Sleep efficiency on R2 was significantly lower than on B1 (t-test, p < 0.05) but not different from R1. To sum up, sleep of aircrews flying multiple transmeridian flights is disrupted during layovers and this effect persists during the two recovery nights. As a result, there is a marked cumulative sleep loss during multi-legs polar route trip in comparison to single leg flights. These findings suggest that following such extensive transmeridian trips, crews should have at least three nights of recovery sleep in their home time zone before returning to duty.

Consolidation of Prospective Memory: Effects of Sleep on Completed and Reinstated Intentions

PubMed Central

Barner, Christine; Seibold, Mitja; Born, Jan; Diekelmann, Susanne

2017-01-01

Sleep has been shown to facilitate the consolidation of prospective memory, which is the ability to execute intended actions at the appropriate time in the future. In a previous study, the sleep benefit for prospective memory was mainly expressed as a preservation of prospective memory performance under divided attention as compared to full attention. Based on evidence that intentions are only remembered as long as they have not been executed yet (cf. ‘Zeigarnik effect’), here we asked whether the enhancement of prospective memory by sleep vanishes if the intention is completed before sleep and whether completed intentions can be reinstated to benefit from sleep again. In Experiment 1, subjects learned cue-associate word pairs in the evening and were prospectively instructed to detect the cue words and to type in the associates in a lexical decision task (serving as ongoing task) 2 h later before a night of sleep or wakefulness. At a second surprise test 2 days later, sleep and wake subjects did not differ in prospective memory performance. Specifically, both sleep and wake groups detected fewer cue words under divided compared to full attention, indicating that sleep does not facilitate the consolidation of completed intentions. Unexpectedly, in Experiment 2, reinstating the intention, by instructing subjects about the second test after completion of the first test, was not sufficient to restore the sleep benefit. However, in Experiment 3, where subjects were instructed about both test sessions immediately after learning, sleep facilitated prospective memory performance at the second test after 2 days, evidenced by comparable cue word detection under divided attention and full attention in sleep participants, whereas wake participants detected fewer cue words under divided relative to full attention. Together, these findings show that for prospective memory to benefit from sleep, (i) the intention has to be active across the sleep period, and (ii) the intention should be induced in temporal proximity to the initial learning session. PMID:28111558

The role of sleep in aesthetic perception and empathy: A mediation analysis.

PubMed

Peretti, Sara; Tempesta, Daniela; Socci, Valentina; Pino, Maria C; Mazza, Monica; Valenti, Marco; De Gennaro, Luigi; Di Dio, Cinzia; Marchetti, Antonella; Ferrara, Michele

2018-02-06

The ability to experience aesthetics plays a fundamental role in human social interactions, as well as the capacity to feel empathy. Some studies have shown that beauty perception shares part of the neural network underlying emotional and empathic abilities, which are also known to affect sleep quality and duration. In this study, we evaluated for the first time the effects of sleep on the relation between aesthetic perception and empathic abilities in healthy subjects using a mediation analysis approach. One-hundred and twenty-six subjects participated in this study. One-hundred and one subjects slept at home (Sleep Group). The remaining 25 subjects were tested as controls after 1 night of sleep deprivation to assess the effects of lack of sleep on aesthetic perception and empathy (Sleep-Deprived Group). All participants underwent one testing session in which they performed a battery of empathy tests and an aesthetic perception task (Golden Beauty). The results showed that sleep duration mediates the relationship between empathy and aesthetic perception in the sleep group. The mediation effect of sleep was more evident on the emotional empathy measures. Conversely, in the sleep deprivation group the lack of correlations among empathy, aesthetic perception and sleep variables did not allow to perform the mediation analysis. These results suggest that adequate sleep duration may play a significant role in improving cognitive and emotional empathic abilities as well as the capability to give accurate aesthetic judgements. © 2018 European Sleep Research Society.

Obstructive Sleep Apnea and 15-Year Cognitive Decline: The Atherosclerosis Risk in Communities (ARIC) Study

PubMed Central

Lutsey, Pamela L.; Bengtson, Lindsay G.S.; Punjabi, Naresh M.; Shahar, Eyal; Mosley, Thomas H.; Gottesman, Rebecca F.; Wruck, Lisa M.; MacLehose, Richard F.; Alonso, Alvaro

2016-01-01

Study Objectives: Prospective data evaluating abnormal sleep quality and quantity with cognitive decline are limited because most studies used subjective data and/or had short follow-up. We hypothesized that, over 15 y of follow-up, participants with objectively measured obstructive sleep apnea (OSA) and other indices of poor sleep quantity and quality would experience greater decline in cognitive functioning than participants with normal sleep patterns. Methods: ARIC participants (n = 966; mean age 61 y, 55% women) with in-home polysomnography (1996–1998) and repeated cognitive testing were followed for 15 y. Three cognitive tests (Delayed Word Recall, Word Fluency, and Digit Symbol Substitution) were administered at two time points (1996–1998 and 2011–2013). Ten additional cognitive tests were administered at the 2011–2013 neurocognitive examination. OSA was modeled using established clinical OSA severity categories. Multivariable linear regression was used to explore associations of OSA and other sleep indices with change in cognitive tests between the two assessments. Results: A median of 14.9 y (max: 17.3) passed between the two cognitive assessments. OSA category and additional indices of sleep (other measures of hypoxemia and disordered breathing, sleep fragmentation, sleep duration) were not associated with change in any cognitive test. Analyses of OSA severity categories and 10 cognitive tests administered only in 2011–2013 also showed little evidence of an association. Conclusions: Overall, abnormal sleep quality and quantity at midlife was not related to cognitive decline and later-life cognition. The effect of adverse sleep quality and quantity on cognitive decline among the elderly remains to be determined. Citation: Lutsey PL, Bengtson LG, Punjabi NM, Shahar E, Mosley TH, Gottesman RF, Wruck LM, MacLehose RF, Alonso A. Obstructive sleep apnea and 15-year cognitive decline: the Atherosclerosis Risk in Communities (ARIC) study. SLEEP 2016;39(2):309–316. PMID:26446113

Cortical region-specific sleep homeostasis in mice: effects of time of day and waking experience.

PubMed

Guillaumin, Mathilde C C; McKillop, Laura E; Cui, Nanyi; Fisher, Simon P; Foster, Russell G; de Vos, Maarten; Peirson, Stuart N; Achermann, Peter; Vyazovskiy, Vladyslav V

2018-04-25

Sleep-wake history, wake behaviours, lighting conditions and circadian time influence sleep, but neither their relative contribution, nor the underlying mechanisms are fully understood. The dynamics of EEG slow-wave activity (SWA) during sleep can be described using the two-process model, whereby the parameters of homeostatic Process S are estimated using empirical EEG SWA (0.5-4 Hz) in non-rapid eye movement sleep (NREM), and the 24-h distribution of vigilance states. We hypothesised that the influence of extrinsic factors on sleep homeostasis, such as the time of day or wake behaviour, would manifest in systematic deviations between empirical SWA and model predictions. To test this hypothesis, we performed parameter estimation and tested model predictions using NREM SWA derived from continuous EEG recordings from the frontal and occipital cortex in mice. The animals showed prolonged wake periods, followed by consolidated sleep, both during the dark and light phases, and wakefulness primarily consisted of voluntary wheel running, learning a new motor skill or novel object exploration. Simulated SWA matched empirical levels well across conditions, and neither waking experience nor time of day had a significant influence on the fit between data and simulation. However, we consistently observed that Process S declined during sleep significantly faster in the frontal than in the occipital area of the neocortex. The striking resilience of the model to specific wake behaviours, lighting conditions and time of day suggests that intrinsic factors underpinning the dynamics of Process S are robust to extrinsic influences, despite their major role in shaping the overall amount and distribution of vigilance states across 24 h.

A description of sleep behaviour in healthy late pregnancy, and the accuracy of self-reports.

PubMed

McIntyre, Jordan P R; Ingham, Cayley M; Hutchinson, B Lynne; Thompson, John M D; McCowan, Lesley M; Stone, Peter R; Veale, Andrew G; Cronin, Robin; Stewart, Alistair W; Ellyett, Kevin M; Mitchell, Edwin A

2016-05-18

The importance of maternal sleep and its contribution to maternal and fetal health during pregnancy is increasingly being recognised. However, the ability to accurately recall sleep practices during pregnancy has been questioned. The aim of this study is to test the accuracy of recall of normal sleep practices in late pregnancy. Thirty healthy women between 35 and 38 weeks of gestation underwent level III respiratory polysomnography (PSG) with infrared digital video recordings in their own homes. Data regarding sleep positions, number of times getting out of bed during the night and respiratory measures were collected. A sleep questionnaire was administered the morning after the recorded sleep. Continuous data were assessed using Spearman's Rho and Bland-Altman. Cohen's Kappa was used to assess recall in the categorical variables. Two-thirds of participants went to sleep on their left side. There was good agreement in sleep onset position between video and questionnaire data (Kappa 0.52), however the there was poor agreement on position on wakening (Kappa 0.24). The number of times getting out of bed during the night was accurately recalled (Kappa 0.65). Twenty five out of 30 participants snored as recorded by PSG. Questionnaire data was inaccurate for this measure. Bland-Altman plots demonstrated acceptable agreement between video and questionnaire data for estimated sleep duration, but not the time taken to fall asleep (sleep latency). One participant had mild obstructive sleep apnoea and another probable high upper airways resistance. Sleep onset position, sleep duration and the number of times getting out of bed during the night were accurately recalled, but sleep latency and sleep position on waking were not. This study identifies the sleep variables that can be accurately obtained by questionnaire and those that cannot.

Effect of a medicinal plant (Passiflora incarnata L) on sleep

PubMed Central

Guerrero, Fructuoso Ayala; Medina, Graciela Mexicano

2017-01-01

INTRODUCTION Extracts of the plant Passiflora incarnata L. (Passifloraceae) were administered intraperitoneally in order to test its effects on sleep. METHOD Experiments were carried out on chronically implanted male adult wistar rats to obtain cerebral (EEG), ocular (EOG) and muscular (EMG) activities throughout their states of vigilance. Polygraphic recordings were taken during 9 continuous hours before and after the extract administration (500 mg/kg). RESULTS Passiflora incarnata induced a significant increment in the total sleep time (p<0.05). This increment was due to an increase in the time spent by animals in slow wave sleep (SWS). Concomitantly, a significant decrement in wakefulness (W) was observed (p<0.05). In contrast, time spent in rapid eye movement (REM) sleep showed a decreasing tendency, since both its frequency and mean duration were reduced. CONCLUSIONS The extracts obtained from Passiflora incarnata can be considered as appropriated sleep inducers. PMID:29410738

Effect of a medicinal plant (Passiflora incarnata L) on sleep.

PubMed

Guerrero, Fructuoso Ayala; Medina, Graciela Mexicano

2017-01-01

Extracts of the plant Passiflora incarnata L. (Passifloraceae) were administered intraperitoneally in order to test its effects on sleep. Experiments were carried out on chronically implanted male adult wistar rats to obtain cerebral (EEG), ocular (EOG) and muscular (EMG) activities throughout their states of vigilance. Polygraphic recordings were taken during 9 continuous hours before and after the extract administration (500 mg/kg). Passiflora incarnata induced a significant increment in the total sleep time ( p <0.05). This increment was due to an increase in the time spent by animals in slow wave sleep (SWS). Concomitantly, a significant decrement in wakefulness (W) was observed ( p <0.05). In contrast, time spent in rapid eye movement (REM) sleep showed a decreasing tendency, since both its frequency and mean duration were reduced. The extracts obtained from Passiflora incarnata can be considered as appropriated sleep inducers.

Sleep disturbance and the effects of extended-release zolpidem during cannabis withdrawal

PubMed Central

Vandrey, Ryan; Smith, Michael T.; McCann, Una D.; Budney, Alan J.; Curran, Erin M.

2011-01-01

Background Sleep difficulty is a common symptom of cannabis withdrawal, but little research has objectively measured sleep or explored the effects of hypnotic medication on sleep during cannabis withdrawal. Methods Twenty daily cannabis users completed a within-subject crossover study. Participants alternated between periods of ad-libitum cannabis use and short-term cannabis abstinence (3 days). Placebo was administered at bedtime during one abstinence period (withdrawal test) and extended-release zolpidem, a non-benzodiazepine GABAA receptor agonist, was administered during the other. Polysomnographic (PSG) sleep architecture measures, subjective ratings, and cognitive performance effects were assessed each day. Results During the placebo-abstinence period, participants had decreased sleep efficiency, total sleep time, percent time spent in Stage 1 and Stage 2 sleep, REM latency and subjective sleep quality, as well as increased sleep latency and time spent in REM sleep compared with when they were using cannabis. Zolpidem attenuated the effects of abstinence on sleep architecture and normalized sleep efficiency scores, but had no effect on sleep latency. Zolpidem was not associated with any significant side effects or next-day cognitive performance impairments. Conclusions These data extend prior research that indicates abrupt abstinence from cannabis can lead to clinically significant sleep disruption in daily users. The findings also indicate that sleep disruption associated with cannabis withdrawal can be attenuated by zolpidem, suggesting that hypnotic medications might be useful adjunct pharmacotherapies in the treatment of cannabis use disorders. PMID:21296508

The association of mothers' and fathers' insomnia symptoms with school-aged children's sleep assessed by parent report and in-home sleep-electroencephalography.

PubMed

Urfer-Maurer, Natalie; Weidmann, Rebekka; Brand, Serge; Holsboer-Trachsler, Edith; Grob, Alexander; Weber, Peter; Lemola, Sakari

2017-10-01

Sleep plays an essential role for children's well-being. Because children's sleep is associated with parental sleep patterns, it must be considered in the family context. As a first aim of the present study, we test whether parental insomnia symptoms are related to children's in-home sleep-electroencephalography (EEG). Second, we examine the association between parental insomnia symptoms and maternal and paternal perception of children's sleep using actor-partner interdependence models. A total of 191 healthy children enrolled in public school and aged 7-12 years took part in the study. Ninety-six were formerly very preterm born children. Children underwent in-home sleep-EEG, and parents reported children's sleep-related behavior by using the German version of the Children's Sleep Habits Questionnaire. Further, parents completed the Insomnia Severity Index to report their own insomnia symptoms. Maternal but not paternal insomnia symptoms were related to less children's EEG-derived total sleep time, more stage 2 sleep, less slow wave sleep, later sleep onset time, and later awakening time. Mothers' and fathers' own insomnia symptoms were related to their reports of children's bedtime resistance, sleep duration, sleep anxiety, night wakings, and/or daytime sleepiness. Moreover, maternal insomnia symptoms were associated with paternal reports of children's bedtime resistance, sleep anxiety, and sleep-disordered breathing. The associations between parental insomnia symptoms and parents' perception of children's sleep could not be explained by children's objectively measured sleep. Mothers' insomnia symptoms and children's objective sleep patterns are associated. Moreover, the parents' own insomnia symptoms might bias their perception of children's sleep-related behavior problems. Copyright © 2017 Elsevier B.V. All rights reserved.

Measuring sleep habits without using a diary: the sleep timing questionnaire

NASA Technical Reports Server (NTRS)

Monk, Timothy H.; Buysse, Daniel J.; Kennedy, Kathy S.; Pods, Jaime M.; DeGrazia, Jean M.; Miewald, Jean M.

2003-01-01

STUDY OBJECTIVES: To develop a single-administration instrument yielding equivalent measures of sleep to those obtained from a formal (2-week) sleep diary. DESIGN & SETTING: A single-administration Sleep riming Questionnaire (STQ) is described (and reproduced in the Appendix). Test-retest reliability was examined in 40 subjects who were given the STQ on two occasions separated by less than 1 year. Convergent validity was measured both by comparing STO-derived measures with objective measures derived from wrist actigraphy (n=23) and by comparing STQ-derived measures with other subjective measures derived from a detailed 2-week sleep diary in two nonoverlapping samples (n=101, 93). Correlations of STQ measures with age and momingness-eveningness (chronotype) were also examined. SUBJECTS: The analyses used sample sizes of 40, 23, 101, and 93 (both genders, overall age range 20y-89y). Most subjects were healthy volunteers; some Study 4 subjects were patients (enrolled in research protocols). RESULTS: Test-retest reliability for the STQ was demonstrated for estimates of bedtime (r = 0.705, p < 0.001) and waketime (r = 0.826, p < 0.001). Convergent validity using wrist actigraphy was demonstrated by correlations of 0.592 (p < 0.005) for bedtime, and of 0.769 (p < 0.001) for waketime. Diary studies indicated STQ bedtime and waketime data to be highly correlated (at about 0.8) with those obtained from a formal 2-week sleep diary. The STQ also provided data on estimated sleep latency and wake after sleep onset (WASO), which correlated reliably (at about 0.7) with average nightly ratings of these variables from a 2-week sleep diary. Mean estimated values of sleep latency and WASO from the two instruments were within 1 minute of each other. ST-derived bedtimes and waketimes correlated with both age and chronotype in the expected direction (older subjects earlier, morning types earlier). CONCLUSION: The STQ may be a reliable valid measure of sleep timing that could provide a time-efficient alternative to traditional sleep diaries.

Sleep and Sleepiness among First-Time Postpartum Parents: A Field- and Laboratory-Based Multimethod Assessment

PubMed Central

Insana, Salvatore P.; Montgomery-Downs, Hawley E.

2012-01-01

The study aim was to compare sleep, sleepiness, fatigue, and neurobehavioral performance among first-time mothers and fathers during their early postpartum period. Participants were 21 first-time postpartum mother-father dyads (N=42) and seven childless control dyads (N=14). Within their natural environment, participants completed one week of wrist actigraphy monitoring, along with multi-day self-administered sleepiness, fatigue, and neurobehavioral performance measures. The assessment week was followed by an objective laboratory based test of sleepiness. Mothers obtained more sleep compared to fathers, but mothers’ sleep was more disturbed by awakenings. Fathers had greater objectively measured sleepiness than mothers. Mothers and fathers did not differ on subjectively measured sleep quality, sleepiness, or fatigue; however, mothers had worse neurobehavioral performance than fathers. Compared to control dyads, postpartum parents experienced greater sleep disturbance, sleepiness, and sleepiness associated impairments. Study results inform social policy, postpartum sleep interventions, and research on postpartum family systems and mechanisms that propagate sleepiness. PMID:22553114

Short sleep mediates the association between long work hours and increased body mass index.

PubMed

Magee, Christopher A; Caputi, Peter; Iverson, Don C

2011-04-01

This study examined whether short sleep duration, physical activity and time spent sitting each day mediated the association between long work hours and body mass index (BMI). Participants included 16,951 middle aged Australian adults who were employed in full time work (i.e. ≥35 h a week). Data on BMI, sleep duration, work hours and other health and demographic variables were obtained through a self-report questionnaire. A multiple mediation model was tested whereby sleep duration, physical activity and amount of time spent sitting were entered as potential mediators between work hours and BMI. The results demonstrated that short sleep partially mediated the association between long work hours and increased BMI in males. In females, long work hours were indirectly related to higher BMI through short sleep. The results provide some support for the hypothesis that long work hours could contribute to obesity via a reduction in sleep duration; this warrants further investigation in prospective studies.

Nocturnal sleep and daytime alertness of aircrew after transmeridian flights

NASA Technical Reports Server (NTRS)

Nicholson, Anthony N.; Pascoe, Peta A.; Spencer, Michael B.; Stone, Barbara M.; Green, Roger L.

1986-01-01

The nocturnal sleep and daytime alertness of aircrew were studied by electroencephalography and the multiple sleep latency test. After a transmeridian flight from London To San Francisco, sleep onset was faster and, although there was increased wakefulness during the second half of the night, sleep duration and efficiency over the whole night were not changed. The progressive decrease in sleep latencies observed normally in the multiple sleep latency test during the morning continued throughout the day after arrival. Of the 13 subjects, 12 took a nap of around 1-h duration in the afternoon preceding the return flight. These naps would have been encouraged by the drowsiness at this time and facilitated by the departure of the aircraft being scheduled during the early evening. An early evening departure had the further advantage that the circadian increase in vigilance expected during the early part of the day would occur during the latter part of the return flight.

Associations of Objectively and Subjectively Measured Sleep Quality with Subsequent Cognitive Decline in Older Community-Dwelling Men: The MrOS Sleep Study

PubMed Central

Blackwell, Terri; Yaffe, Kristine; Laffan, Alison; Ancoli-Israel, Sonia; Redline, Susan; Ensrud, Kristine E.; Song, Yeonsu; Stone, Katie L.

2014-01-01

Study Objectives: To examine associations of objectively and subjectively measured sleep with subsequent cognitive decline. Design: A population-based longitudinal study. Setting: Six centers in the United States. Participants: Participants were 2,822 cognitively intact community-dwelling older men (mean age 76.0 ± 5.3 y) followed over 3.4 ± 0.5 y. Interventions: None. Measurements and Results: Objectively measured sleep predictors from wrist actigraphy: total sleep time (TST), sleep efficiency (SE), wake after sleep onset (WASO), number of long wake episodes (LWEP). Self-reported sleep predictors: sleep quality (Pittsburgh Sleep Quality Index [PSQI]), daytime sleepiness (Epworth Sleepiness Scale [ESS]), TST. Clinically significant cognitive decline: five-point decline on the Modified Mini-Mental State examination (3MS), change score for the Trails B test time in the worse decile. Associations of sleep predictors and cognitive decline were examined with logistic regression and linear mixed models. After multivariable adjustment, higher levels of WASO and LWEP and lower SE were associated with an 1.4 to 1.5-fold increase in odds of clinically significant decline (odds ratio 95% confidence interval) Trails B test: SE < 70% versus SE ≥ 70%: 1.53 (1.07, 2.18); WASO ≥ 90 min versus WASO < 90 min: 1.47 (1.09, 1.98); eight or more LWEP versus fewer than eight: 1.38 (1.02, 1.86). 3MS: eight or more LWEP versus fewer than eight: 1.36 (1.09, 1.71), with modest relationships to linear change in cognition over time. PSQI was related to decline in Trails B performance (3 sec/y per standard deviation increase). Conclusions: Among older community-dwelling men, reduced sleep efficiency, greater nighttime wakefulness, greater number of long wake episodes, and poor self-reported sleep quality were associated with subsequent cognitive decline. Citation: Blackwell T; Yaffe K; Laffan A; Ancoli-Israel S; Redline S; Ensrud KE; Song Y; Stone KL. Associations of objectively and subjectively measured sleep quality with subsequent cognitive decline in older community-dwelling men: the MrOS sleep study. SLEEP 2014;37(4):655-663. PMID:24899757

Poor sleep quality predicts deficient emotion information processing over time in early adolescence.

PubMed

Soffer-Dudek, Nirit; Sadeh, Avi; Dahl, Ronald E; Rosenblat-Stein, Shiran

2011-11-01

There is deepening understanding of the effects of sleep on emotional information processing. Emotion information processing is a key aspect of social competence, which undergoes important maturational and developmental changes in adolescence; however, most research in this area has focused on adults. Our aim was to test the links between sleep and emotion information processing during early adolescence. Sleep and facial information processing were assessed objectively during 3 assessment waves, separated by 1-year lags. Data were obtained in natural environments-sleep was assessed in home settings, and facial information processing was assessed at school. 94 healthy children (53 girls, 41 boys), aged 10 years at Time 1. N/A. Facial information processing was tested under neutral (gender identification) and emotional (emotional expression identification) conditions. Sleep was assessed in home settings using actigraphy for 7 nights at each assessment wave. Waking > 5 min was considered a night awakening. Using multilevel modeling, elevated night awakenings and decreased sleep efficiency significantly predicted poor performance only in the emotional information processing condition (e.g., b = -1.79, SD = 0.52, confidence interval: lower boundary = -2.82, upper boundary = -0.076, t(416.94) = -3.42, P = 0.001). Poor sleep quality is associated with compromised emotional information processing during early adolescence, a sensitive period in socio-emotional development.

General intelligence predicts memory change across sleep.

PubMed

Fenn, Kimberly M; Hambrick, David Z

2015-06-01

Psychometric intelligence (g) is often conceptualized as the capability for online information processing but it is also possible that intelligence may be related to offline processing of information. Here, we investigated the relationship between psychometric g and sleep-dependent memory consolidation. Participants studied paired-associates and were tested after a 12-hour retention interval that consisted entirely of wake or included a regular sleep phase. We calculated the number of word-pairs that were gained and lost across the retention interval. In a separate session, participants completed a battery of cognitive ability tests to assess g. In the wake group, g was not correlated with either memory gain or memory loss. In the sleep group, we found that g correlated positively with memory gain and negatively with memory loss. Participants with a higher level of general intelligence showed more memory gain and less memory loss across sleep. Importantly, the correlation between g and memory loss was significantly stronger in the sleep condition than in the wake condition, suggesting that the relationship between g and memory loss across time is specific to time intervals that include sleep. The present research suggests that g not only reflects the capability for online cognitive processing, but also reflects capability for offline processes that operate during sleep.

Chronotype influences activity circadian rhythm and sleep: differences in sleep quality between weekdays and weekend.

PubMed

Vitale, Jacopo A; Roveda, Eliana; Montaruli, Angela; Galasso, Letizia; Weydahl, Andi; Caumo, Andrea; Carandente, Franca

2015-04-01

Several studies have shown the differences among chronotypes in the circadian rhythm of different physiological variables. Individuals show variation in their preference for the daily timing of activity; additionally, there is an association between chronotype and sleep duration/sleep complaints. Few studies have investigated sleep quality during the week days and weekends in relation to the circadian typology using self-assessment questionnaires or actigraphy. The purpose of this study was to use actigraphy to assess the relationship between the three chronotypes and the circadian rhythm of activity levels and to determine whether sleep parameters respond differently with respect to time (weekdays versus the weekend) in Morning-types (M-types), Neither-types (N-types) and Evening-types (E-types). The morningness-eveningness questionnaire (MEQ) was administered to 502 college students to determine their chronotypes. Fifty subjects (16 M-types, 15 N-types and 19 E-types) were recruited to undergo a 7-days monitoring period with an actigraph (Actiwacth® actometers, CNT, Cambridge, UK) to evaluate their sleep parameters and the circadian rhythm of their activity levels. To compare the amplitude and the acrophase among the three chronotypes, we used a one-way ANOVA followed by the Tukey-Kramer post-hoc test. To compare the Midline Estimating Statistic of Rhythm (MESOR) among the three chronotypes, we used a Kruskal-Wallis non-parametric test followed by pairwise comparisons that were performed using Dunn's procedure with a Bonferroni correction for multiple comparisons. The analysis of each sleep parameter was conducted using the mixed ANOVA procedure. The results showed that the chronotype was influenced by sex (χ(2) with p = 0.011) and the photoperiod at birth (χ(2) with p < 0.05). Though the MESOR and amplitude of the activity levels were not different among the three chronotypes, the acrophases compared by the ANOVA post-hoc test were significantly different (p < 0.001). The ANOVA post-hoc test revealed the presence of a significant difference (p < 0.001) between the M-types (14:32 h) and E-types (16:53 h). There was also a significant interaction between the chronotype and four sleep parameters: Sleep end, Assumed Sleep, Immobility Time and Sleep Efficiency. Sleep Efficiency showed the same patterns as did Assumed Sleep and Immobility Time: the Sleep Efficiency of the E-types was poorer than that of the M- and N-types during weekdays (77.9% ± 7.0 versus 84.1% ± 4.9 and 84.1% ± 5.2) but was similar to that measured in the M- and N-types during the weekend. Sleep Latency and Movement and Fragmentation Index were not different among the three chronotypes and did not change on the weekend compared with weekdays. This study highlights two key findings: first, we observed that the circadian rhythm of activity levels was influenced by the chronotype; second, the chronotype had a significant effect on sleep parameters: the E-types had a reduced sleep quality and quantity compared with the M- and N-types during weekdays, whereas the E-types reached the same levels as the other chronotypes during the weekends. These findings suggest that E-types accumulate a sleep deficit during weekdays due to social and academic commitments and that they recover from this deficit during "free days" on the weekend.

Sleep duration and sleep quality in people with and without intellectual disability: A meta-analysis.

PubMed

Surtees, Andrew D R; Oliver, Chris; Jones, Chris A; Evans, David L; Richards, Caroline

2017-11-28

This study provides the first meta-analysis of the purported differences in sleep time and sleep quality between people with and without intellectual disabilities. Twenty-one papers were identified that compared sleep time and/or sleep quality in people with and without intellectual disabilities. The meta-analysis of sleep time revealed that people with an intellectual disability slept for 18 min less, on average, than people without an intellectual disability. This significant difference was limited to those studies that tested groups of people with an identified genetic syndrome or developmental disorder. The analysis of sleep quality also concluded that people with intellectual disabilities experienced poorer sleep: In 93% of comparisons between groups, sleep was found to be of poorer quality in the group of people with intellectual disabilities. There were no differences found between studies that measured sleep objectively and those that used diary or questionnaire measures. Notably, most samples were drawn from populations of people with specified genetic syndromes or developmental disorders, rather than intellectual disability of heterogeneous origin. Similarly, most studies investigated sleep in children, although there was no evidence that the differences between the groups reduced during adulthood. Most studies used highly-regarded objective measures of sleep, such as polysomnography or actigraphy, although methodological flaws were evident in the identification of samples and the measurement of intellectual disability. Copyright © 2017 Elsevier Ltd. All rights reserved.

Dynamic circadian modulation in a biomathematical model for the effects of sleep and sleep loss on waking neurobehavioral performance.

PubMed

McCauley, Peter; Kalachev, Leonid V; Mollicone, Daniel J; Banks, Siobhan; Dinges, David F; Van Dongen, Hans P A

2013-12-01

Recent experimental observations and theoretical advances have indicated that the homeostatic equilibrium for sleep/wake regulation--and thereby sensitivity to neurobehavioral impairment from sleep loss--is modulated by prior sleep/wake history. This phenomenon was predicted by a biomathematical model developed to explain changes in neurobehavioral performance across days in laboratory studies of total sleep deprivation and sustained sleep restriction. The present paper focuses on the dynamics of neurobehavioral performance within days in this biomathematical model of fatigue. Without increasing the number of model parameters, the model was updated by incorporating time-dependence in the amplitude of the circadian modulation of performance. The updated model was calibrated using a large dataset from three laboratory experiments on psychomotor vigilance test (PVT) performance, under conditions of sleep loss and circadian misalignment; and validated using another large dataset from three different laboratory experiments. The time-dependence of circadian amplitude resulted in improved goodness-of-fit in night shift schedules, nap sleep scenarios, and recovery from prior sleep loss. The updated model predicts that the homeostatic equilibrium for sleep/wake regulation--and thus sensitivity to sleep loss--depends not only on the duration but also on the circadian timing of prior sleep. This novel theoretical insight has important implications for predicting operator alertness during work schedules involving circadian misalignment such as night shift work.

gamma-Aminobutyric acid-activated chloride channels: relationship to genetic differences in ethanol sensitivity.

PubMed

Allan, A M; Spuhler, K P; Harris, R A

1988-03-01

We demonstrated recently that low concentrations of ethanol enhanced the muscimol-stimulated chloride influx in cerebellar membranes from long sleep (LS-ethanol sensitive) mice, but had no effect on membranes from short sleep (SS-ethanol resistant) mice. The LS and SS were selected from a heterogeneous stock (HS) of mice for differential sensitivity to the hypnotic effects of ethanol as measured by the duration of the loss of the righting reflex (sleep time). In the present study, we tested 100 HS for ethanol sleep time. The mice with the shortest sleep time (HS-SS) and the mice with the longest sleep time (HS-LS) were selected and tested for the effect of ethanol and muscimol on chloride flux in cerebellum. The effects of ethanol and muscimol on both cerebellar and cortical chloride flux were also examined in rats from the 7th generation selected for differential sensitivity to the hypnotic effects of ethanol (high acute ethanol sensitive rats-HAS and low acute ethanol sensitive rats-LAS). Low concentrations of ethanol (10-30 mM) potentiated muscimol stimulation of 36Cl- uptake in both cortical and cerebellar membranes prepared from ethanol-sensitive animals (HS-LS and HAS). None of the ethanol concentrations tested altered stimulated chloride uptake in ethanol-resistant animals (HS-SS and LAS). No differences in muscimol stimulation of chloride uptake were observed between the pairs of selected lines. These findings strongly suggest that genetic differences in ethanol hypnosis are related to differences in the sensitivity of gamma-aminobutyric acid-operated chloride channels to ethanol.

Out Like a Light? The Effects of a Diurnal Husbandry Schedule on Mouse Sleep and Behavior.

PubMed

Robinson-Junker, Amy L; O'hara, Bruce F; Gaskill, Brianna N

2018-03-01

Sleep disruption in humans, caused by shift work, can be detrimental to physical and behavioral health. Nocturnal laboratory mice may experience a similar disruption caused by human daytime activities, but whether this disruption affects their welfare is unknown. We used 48 mice (CD1, C57BL/6, and BALB/c of both sexes) in a factorial design to test a sleep disruption treatment, in which mice were disturbed by providing routine husbandry at either 1000 or 2200 during a 12:12-h light:dark cycle, with lights on at 0700. All mice were exposed for 1 wk to each disruption treatment, and we used a noninvasive sleep monitoring apparatus to monitor and record sleep. To determine whether providing nesting material ameliorated effects of sleep disruption, we tested 4 amounts of nesting material (3, 6, 9, or 12 g) and continuously recorded sleep in the home cage for 2 wk. C57BL/6 mice, regardless of sex or disruption timing, slept the least overall. There was a strong interaction of sex and type of mouse on sleep across 24 h. Mice slept less during the first day of the daytime disturbance than on day 6. These results suggest that disturbance timing affects sleep patterns in mice but not their overall amount of sleep and that the changes in sleep patterns vary between mouse type and sex. In addition, mice appear to both anticipate and acclimate to human activity during the day. Our welfare checks were possibly too predictable and inconsequential to induce true sleep disruption.

The Maintenance of Wakefulness Test and driving simulator performance.

PubMed

Banks, Siobhan; Catcheside, Peter; Lack, Leon C; Grunstein, Ron R; McEvoy, R Doug

2005-11-01

It has been suggested that the Maintenance of Wakefulness Test (MWT) may be clinically useful to assess fitness to drive, yet little is known about the actual relationship between sleep latency and driving performance. This study examined the ability of 2 MWT trials to predict driving-simulator performance in healthy individuals. Experimental. NA. Twenty healthy volunteers (mean age 22.8 years; 9 men). NA. The MWT and driving-simulator performance were examined under 2 conditions-partial sleep deprivation and a combination of partial sleep deprivation and alcohol consumption. Each subject was studied a week apart, with the order randomly assigned. Subjects completed a nighttime 70-minute AusEd driving simulation task and two 40-minute MWT trials, 1 before (MWT1) and 1 after (MWT2) the driving task. In the sleep-deprived condition, the MWT1 sleep latency was inversely correlated with braking reaction time. During the partial sleep deprivation and alcohol condition, the number of microsleeps during the driving task, steering deviation, braking reaction time, and crashes all negatively correlated with the MWT1 sleep latency. Additionally, construction of a receiver-operator characteristic curve revealed that MWT1 sleep latency in the partial sleep deprivation plus alcohol condition significantly discriminated subjects who had a crash from those who did not. These results indicate that sleep latency on the MWT is a reasonable predictor of driving simulator performance in sleepy, alcohol-impaired, normal subjects. Further research is needed to examine the relationship between daytime MWT results and driving simulator performance in sleepy patients (eg, those with obstructive sleep apnea) and in experimentally sleep-deprived normal subjects.

Sleep and wakefulness in aircrew before and after transoceanic flights

NASA Technical Reports Server (NTRS)

Dement, William C.; Seidel, Wesley F.; Cohen, Suzanne A.; Carskadon, Mary A.; Bliwise, Nancy G.

1986-01-01

The effects of rapid transmeridian flight on sleep and wakefulness were studied in aircrew members before and after flying one of two routes: San Francisco (SFO) to London (LHR) or SFO to Tokyo. After an adaptation night, sleep and daytime sleepiness were measured objectively in SFO and during the first layover (L/O) of the target trip, using the 'core measures' described by Graeber et al. (1986) and respiration parameters, and the Multiple Sleep Latency Test (MSLT) described by Carscadon (1982); postsleep questionnaires provided subjective assessments. It was found that baseline sleep is not an ideal basis for subsequent comparison; nevertheless, there was an indication that L/O sleep periods tended to provide either less total sleep or less efficient sleep. During baseline, there was significant midday sleepiness tendency as measured by the MSLT; this tendency occurred at almost the same time on the second L/O day in LHR. Recommendations are offered for the adjustment of flight times and for scheduling times of permitted napping as accommodations for the periods of sleepiness tendency.

French consensus. Idiopathic hypersomnia: Investigations and follow-up.

PubMed

Leu-Semenescu, S; Quera-Salva, M-A; Dauvilliers, Y

Idiopathic hypersomnia is a rare, central hypersomnia, recently identified and to date of unknown physiopathology. It is characterised by a more or less permanent, excessive daytime sleepiness, associated with long and unrefreshing naps. Night-time sleep is of good quality, excessive in quantity, associated with sleep inertia in the subtype previously described as "with long sleep time". Diagnosis of idiopathic hypersomnia is complex due to the absence of a quantifiable biomarker, the heterogeneous symptoms, which overlap with the clinical picture of type 2 narcolepsy, and its variable evolution over time. Detailed evaluation enables other frequent causes of somnolence, such as depression or sleep deprivation, to be eliminated. Polysomnography and multiple sleep latency tests (MSLT) are essential to rule out other sleep pathologies and to objectify excessive daytime sleepiness. Sometimes the MSLT do not show excessive sleepiness, hence a continued sleep recording of at least 24hours is necessary to show prolonged sleep (>11h/24h). In this article, we propose recommendations for the work-up to be carried out during diagnosis and follow-up for patients suffering from idiopathic hypersomnia. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

The association between sleep duration and physical performance in Chinese community-dwelling elderly.

PubMed

Fu, Liyuan; Jia, Liye; Zhang, Wen; Han, Peipei; Kang, Li; Ma, Yixuan; Yu, Hairui; Zhai, Tianqi; Chen, Xiaoyu; Guo, Qi

2017-01-01

Physical performance is an important healthy factor in elder people. Good living habits, which include sleep, can maintain physical strength and physical performance. The aim of the present study was to conduct a cross-sectional study to determine the association between total sleep duration and physical performance. Our study population comprised residents of the township central hospital in the suburban of Tianjin, China. We measured muscle strength, walk speed and balance function by grip, 4-m walk test and timed up and go test (TUGT). We divided sleep duration into four groups <7h, 7-8h, >8-9h, >9h. A total 898 participants had completed data (392 men and 506 women, mean age 67.71 years). In man, adjusted sleep duration was associated with lower grip in > 9 h group, the mean value (95% CI) was 0.429 (0.409, 0.448), and longer TUGT time was also associated with long sleep duration, 10.46s (9.97 s, 10.95 s). In women, adjusted slower 4-m walk speed present an inverse U-shaped relation with sleep duration, by 0.93 m/s (0.86 m/s, 0.98 m/s), 0.97 m/s (0.96 m/s, 1.00 m/s), 0.97 m/s (0.95 m/s, 0.99 m/s) and 0.92 m/s (0.89 m/s, 0.96 m/s); longer TUGT time were associated with long sleep duration (> 9 h), by 11.23 s (10.70 s, 11.77 s). In Chinese community-dwelling elderly, lower muscle strength and lower balance function were associated with long sleep duration in men. Slower walk speed and lower balance function were associated with long sleep duration in women.

A global quantification of "normal" sleep schedules using smartphone data.

PubMed

Walch, Olivia J; Cochran, Amy; Forger, Daniel B

2016-05-01

The influence of the circadian clock on sleep scheduling has been studied extensively in the laboratory; however, the effects of society on sleep remain largely unquantified. We show how a smartphone app that we have developed, ENTRAIN, accurately collects data on sleep habits around the world. Through mathematical modeling and statistics, we find that social pressures weaken and/or conceal biological drives in the evening, leading individuals to delay their bedtime and shorten their sleep. A country's average bedtime, but not average wake time, predicts sleep duration. We further show that mathematical models based on controlled laboratory experiments predict qualitative trends in sunrise, sunset, and light level; however, these effects are attenuated in the real world around bedtime. Additionally, we find that women schedule more sleep than men and that users reporting that they are typically exposed to outdoor light go to sleep earlier and sleep more than those reporting indoor light. Finally, we find that age is the primary determinant of sleep timing, and that age plays an important role in the variability of population-level sleep habits. This work better defines and personalizes "normal" sleep, produces hypotheses for future testing in the laboratory, and suggests important ways to counteract the global sleep crisis.

Assessing the sleeping habits of patients in a sleep disorder centre: a review of sleep diary accuracy.

PubMed

Lawrence, Geoffrey; Muza, Rexford

2018-01-01

Excessive daytime sleepiness (EDS) is a complaint common to many aspects of medicine. There are primary and secondary causes for EDS, with secondary causes including a large number of common conditions. Primary causes, such as narcolepsy, are much rarer. When assessing for primary hypersomnia, restricted or fragmented sleep must be ruled out. This process involves assessment of sleeping habits using a sleep diary and/or actigraphy. Clinicians are suspicious of the accuracy with which patients use the former. This review aims to evaluate the accuracy of a sleep diary study against the 'objective gold standard' actigraphy report. Data from 35 patients at a Sleep Disorder Centre who underwent both a sleep diary and actigraphy study for suspected primary hypersomnia in 2016 was collected. Mean values of four variables were calculated: 'time of lights out', 'time to fall asleep', 'time of waking' and 'sleep time'. The 'similarity' was assessed. This was a term defined in three different ways: if sleep diary values are accurate to within 20, 30 and 60 min respectively. Percentage 'similarity', mean time differences and standard deviations (SDs) were calculated for each variable. A paired t -test was also performed to assess the significance of the time differences between the two modalities. Least accurate was 'sleep time', with 14.7%, 23.5% and 58.8% of patients within 20, 30 and 60 min of the actigraphy respectively. Mean time difference for this variable was 66 min (versus 33, 15 and 22). 'Time to fall asleep' was most accurate, with 76.5%, 82.4% and 100% 'similarity' respectively. The clinically acceptable accuracy has no universal definition, so clinicians must use experience and reasoning to determine this level to interpret this data. The review suggests that some variables are entered with high accuracy, and the diary is low cost and adds subjective information that cannot be gathered from actigraphy. Therefore, use is recommended to continue alongside actigraphy.

Reversible obstructive sleep apnea caused by occupational exposure to guar gum dust.

PubMed

Leznoff, A; Haight, J S; Hoffstein, V

1986-05-01

This report describes a case of reversible obstructive sleep apnea caused by occupational exposure to an inhaled allergen, guar gum powder. The patient, a pet food plant employee, also experienced severe cough, rhinitis, and conjunctivitis. Skin tests confirmed the specific guar allergy. Pharyngeal cross-sectional area was smaller than normal. Pulmonary function studies, histamine challenge tests, nasal air-flow resistance measurements, and nocturnal polysomnography were performed on 3 separate occasions: while the patient was working at his usual occupation, at the end of a 3-wk holiday, and after a guar dust challenge in an inhalation chamber. Pulmonary function and histamine challenge tests were consistently normal. At the time of the initial tests, nasal resistance was elevated, and nocturnal polysomnography revealed obstructive sleep apnea. After absence from work, obstructive sleep apnea resolved, and the nasal resistance returned to normal. After challenge with guar gum dust, the patient developed increased resistance to nasal air flow, and obstructive sleep apnea reappeared. This case demonstrates that allergy can cause reversible obstructive sleep apnea and that occupational exposure should be considered in the assessment of patients with this disease.

Effect of bright light therapy on delayed sleep/wake cycle and reaction time of athletes participating in the Rio 2016 Olympic Games.

PubMed

Rosa, João Paulo P; Silva, Andressa; Rodrigues, Dayane F; Simim, Mário Antônio; Narciso, Fernanda V; Tufik, Sergio; Bichara, Jorge J; Pereira, Sebastian Rafael D; Da Silva, Sidney C; de Mello, Marco Tulio

2018-04-16

This study investigated the effect of using an artificial bright light on the entrainment of the sleep/wake cycle as well as the reaction times of athletes before the Rio 2016 Olympic Games. A total of 22 athletes from the Brazilian Olympic Swimming Team were evaluated, with the aim of preparing them to compete at a time when they would normally be about to go to bed for the night. During the 8-day acclimatization period, their sleep/wake cycles were assessed by actigraphy, with all the athletes being treated with artificial light therapy for between 30 and 45 min (starting at day 3). In addition, other recommendations to improve sleep hygiene were made to the athletes. In order to assess reaction times, the Psychomotor Vigilance Test was performed before (day 1) and after (day 8) the bright light therapy. As a result of the intervention, the athletes slept later on the third (p = 0.01), seventh (p = 0.01) and eighth (p = 0.01) days after starting bright light therapy. Regarding reaction times, when tested in the morning the athletes showed improved average (p = 0.01) and minimum reaction time (p = 0.03) when comparing day 8 to day 1. When tested in the evening, they showed improved average (p = 0.04), minimum (p = 0.03) and maximum reaction time (p = 0.02) when comparing day 8 to day 1. Light therapy treatment delayed the sleep/wake cycles and improved reaction times of members of the swimming team. The use of bright light therapy was shown to be effective in modulating the sleep/wake cycles of athletes who had to perform in competitions that took place late at night.

To study or to sleep? The academic costs of extra studying at the expense of sleep.

PubMed

Gillen-O'Neel, Cari; Huynh, Virginia W; Fuligni, Andrew J

2013-01-01

This longitudinal study examined how nightly variations in adolescents' study and sleep time are associated with academic problems on the following day. Participants (N = 535, 9th grade M(age) = 14.88) completed daily diaries every day for 14 days in 9th, 10th, and 12th grades. Results suggest that regardless of how much a student generally studies each day, if that student sacrifices sleep time to study more than usual, he or she will have more trouble understanding material taught in class and be more likely to struggle on an assignment or test the following day. Because students are increasingly likely to sacrifice sleep time for studying in the latter years of high school, this negative dynamic becomes increasingly prevalent over time. © 2012 The Authors. Child Development © 2012 Society for Research in Child Development, Inc.

Emotional working memory during sustained wakefulness.

PubMed

Tempesta, Daniela; De Gennaro, Luigi; Presaghi, Fabio; Ferrara, Michele

2014-12-01

In the present study we investigated whether one night of sleep deprivation can affect working memory (WM) performance with emotional stimuli. Twenty-five subjects were tested after one night of sleep deprivation and after one night of undisturbed sleep at home. As a second aim of the study, to evaluate the cumulative effects of sleep loss and of time-of-day changes on emotional WM ability, the subjects were tested every 4 h, from 22:00 to 10:00 hours, in four testing sessions during the sleep deprivation period (deprivation sessions: D1, D2, D3 and D4). Subjects performed the following test battery: Psychomotor Vigilance Task, 0-back task, 2-back task and an 'emotional 2-back task' with neutral, positive and negative emotional pictures selected from the International Affective Picture System. Results showed lower accuracy in the emotional WM task when the participants were sleep-deprived relative to when they had slept, suggesting the crucial role of sleep for preserving WM ability. In addition, the accuracy for the negative pictures remains stable during the sessions performed from 22:00 to 06:00 hours (D1, D2 and D3), while it drops at the D4 session, when the participants had accumulated the longest sleep debt. It is suggested that, during sleep loss, attentional and WM mechanisms may be sustained by the higher arousing characteristics of the emotional (negative) stimuli. © 2014 European Sleep Research Society.

What drives sleep-dependent memory consolidation: greater gain or less loss?

PubMed

Fenn, Kimberly M; Hambrick, David Z

2013-06-01

When memory is tested after a delay, performance is typically better if the retention interval includes sleep. However, it is unclear what accounts for this well-established effect. It is possible that sleep enhances the retrieval of information, but it is also possible that sleep protects against memory loss that normally occurs during waking activity. We developed a new research approach to investigate these possibilities. Participants learned a list of paired-associate items and were tested on the items after a 12-h interval that included waking or sleep. We analyzed the number of items gained versus the number of items lost across time. The sleep condition showed more items gained and fewer items lost than did the wake condition. Furthermore, the difference between the conditions (favoring sleep) in lost items was greater than the difference in gain, suggesting that loss prevention may primarily account for the effect of sleep on declarative memory consolidation. This finding may serve as an empirical constraint on theories of memory consolidation.

Duration of sleep inertia after napping during simulated night work and in extended operations.

PubMed

Signal, Tracey Leigh; van den Berg, Margo J; Mulrine, Hannah M; Gander, Philippa H

2012-07-01

Due to the mixed findings of previous studies, it is still difficult to provide guidance on how to best manage sleep inertia after waking from naps in operational settings. One of the few factors that can be manipulated is the duration of the nap opportunity. The aim of the present study was to investigate the magnitude and time course of sleep inertia after waking from short (20-, 40- or 60-min) naps during simulated night work and extended operations. In addition, the effect of sleep stage on awakening and duration of slow wave sleep (SWS) on sleep inertia was assessed. Two within-subject protocols were conducted in a controlled laboratory setting. Twenty-four healthy young men (Protocol 1: n = 12, mean age = 25.1 yrs; Protocol 2: n = 12, mean age = 23.2 yrs) were provided with nap opportunities of 20-, 40-, and 60-min (and a control condition of no nap) ending at 02:00 h after ∼20 h of wakefulness (Protocol 1 [P1]: simulated night work) or ending at 12:00 h after ∼30 h of wakefulness (Protocol 2 [P2]: simulated extended operations). A 6-min test battery, including the Karolinska Sleepiness Scale (KSS) and the 4-min 2-Back Working Memory Task (WMT), was repeated every 15 min the first hour after waking. Nap sleep was recorded polysomnographically, and in all nap opportunities sleep onset latency was short and sleep efficiency high. Mixed-model analyses of variance (ANOVA) for repeated measures were calculated and included the factors time (time post-nap), nap opportunity (duration of nap provided), order (order in which the four protocols were completed), and the interaction of these terms. Results showed no test x nap opportunity effect (i.e., no effect of sleep inertia) on KSS. However, WMT performance was impaired (slower reaction time, fewer correct responses, and increased omissions) on the first test post-nap, primarily after a 40- or 60-min nap. In P2 only, performance improvement was evident 45 min post-awakening for naps of 40 min or more. In ANOVAs where sleep stage on awakening was included, the test x nap opportunity interaction was significant, but differences were between wake and non-REM Stage 1/Stage 2 or wake and SWS. A further series of ANOVAs showed no effect of the duration of SWS on sleep inertia. The results of this study demonstrate that no more than 15 min is required for performance decrements due to sleep inertia to dissipate after nap opportunities of 60 min or less, but subjective sleepiness is not a reliable indicator of this effect. Under conditions where sleep is short, these findings also suggest that SWS, per se, does not contribute to more severe sleep inertia. When wakefulness is extended and napping occurs at midday (i.e., P2), nap opportunities of 40- and 60-min have the advantage over shorter duration sleep periods, as they result in performance benefits ∼45 min after waking.

The effect of alpha rhythm sleep on EEG activity and individuals' attention.

PubMed

Kim, Seon Chill; Lee, Myoung Hee; Jang, Chel; Kwon, Jung Won; Park, Joo Wan

2013-12-01

[Purpose] This study examined whether the alpha rhythm sleep alters the EEG activity and response time in the attention and concentration tasks. [Subjects and Methods] The participants were 30 healthy university students, who were randomly and equally divided into two groups, the experimental and control groups. They were treated using the Happy-sleep device or a sham device, respectively. All participants had a one-week training period. Before and after training sessions, a behavioral task test was performed and EEG alpha waves were measured to confirm the effectiveness of training on cognitive function. [Results] In terms of the behavioral task test, reaction time (RT) variations in the experimental group were significantly larger than in the control group for the attention item. Changes in the EEG alpha power in the experimental group were also significantly larger than those of the control group. [Conclusions] These findings suggest that sleep induced using the Happy-sleep device modestly enhances the ability to pay attention and focus during academic learning.

The effect of sleep quality on academic performance is mediated by Internet use time: DADOS study.

PubMed

Adelantado-Renau, Mireia; Diez-Fernandez, Ana; Beltran-Valls, Maria Reyes; Soriano-Maldonado, Alberto; Moliner-Urdiales, Diego

2018-05-19

The aims of the present study were to analyze the association of sleep patterns with academic and cognitive performance in adolescents, and to test the potential mediating effect of different activities of screen media usage on this association. A sample of 269 adolescents (140 boys) aged 14 years from the baseline data of the Deporte, ADOlescencia y Salud study completed questionnaires about sleep quality, cognitive performance, and leisure-time sedentary behaviors. Sleep duration was objectively computed using a wrist-worn GENEActiv accelerometer and academic performance was analyzed through school records. Sleep quality (but not sleep duration) was associated with all the academic performance indicators (all p<0.05). Analysis of covariance revealed higher grades among adolescents with better sleep quality (PSQI≤5; all p<0.05). These analyses showed no differences regarding cognitive performance. Internet use time was revealed as a mediator of the association between sleep quality and academic performance, being significant for all academic performance indicators (P M ranging from 15.5% to 16.0%). The association between sleep quality and academic performance in adolescents is mediated by time of Internet use. Overall, reducing Internet use in adolescents could be an achievable intervention for improving sleep quality, with potentially positive effects on academic performance. Copyright © 2018 Sociedade Brasileira de Pediatria. Published by Elsevier Editora Ltda. All rights reserved.

Poor sleep quality is associated with a negative cognitive bias and decreased sustained attention.

PubMed

Gobin, Christina M; Banks, Jonathan B; Fins, Ana I; Tartar, Jaime L

2015-10-01

Poor sleep quality has been demonstrated to diminish cognitive performance, impair psychosocial functioning and alter the perception of stress. At present, however, there is little understanding of how sleep quality affects emotion processing. The aim of the present study was to determine the extent to which sleep quality, measured through the Pittsburg Sleep Quality Index, influences affective symptoms as well as the interaction between stress and performance on an emotional memory test and sustained attention task. To that end, 154 undergraduate students (mean age: 21.27 years, standard deviation = 4.03) completed a series of measures, including the Pittsburg Sleep Quality Index, the Sustained Attention to Response Task, an emotion picture recognition task and affective symptom questionnaires following either a control or physical stress manipulation, the cold pressor test. As sleep quality and psychosocial functioning differ among chronotypes, we also included chronotype and time of day as variables of interest to ensure that the effects of sleep quality on the emotional and non-emotional tasks were not attributed to these related factors. We found that poor sleep quality is related to greater depressive symptoms, anxiety and mood disturbances. While an overall relationship between global Pittsburg Sleep Quality Index score and emotion and attention measures was not supported, poor sleep quality, as an independent component, was associated with better memory for negative stimuli and a deficit in sustained attention to non-emotional stimuli. Importantly, these effects were not sensitive to stress, chronotype or time of day. Combined, these results suggest that individuals with poor sleep quality show an increase in affective symptomatology as well as a negative cognitive bias with a concomitant decrease in sustained attention to non-emotional stimuli. © 2015 European Sleep Research Society.

Sleep and Cognitive Function in Multiple Sclerosis.

PubMed

Braley, Tiffany J; Kratz, Anna L; Kaplish, Neeraj; Chervin, Ronald D

2016-08-01

To examine associations between cognitive performance and polysomnographic measures of obstructive sleep apnea in patients with multiple sclerosis (MS). Participants underwent a comprehensive MS-specific cognitive testing battery (the Minimal Assessment of Cognitive Function in MS, or MACFIMS) and in-laboratory overnight PSG. In adjusted linear regression models, the oxygen desaturation index (ODI) and minimum oxygen saturation (MinO2) were significantly associated with performance on multiple MACFIMS measures, including the Paced Auditory Serial Addition Test (PASAT; 2-sec and 3-sec versions), which assesses working memory, processing speed, and attention, and on the Brief Visuospatial Memory Test-Revised, a test of delayed visual memory. The respiratory disturbance index (RDI) was also significantly associated with PASAT-3 scores as well as the California Verbal Learning Test-II (CVLT-II) Discriminability Index, a test of verbal memory and response inhibition. Among these associations, apnea severity measures accounted for between 12% and 23% of the variance in cognitive test performance. Polysomnographic measures of sleep fragmentation (as reflected by the total arousal index) and total sleep time also showed significant associations with a component of the CVLT-II that assesses response inhibition, explaining 18% and 27% of the variance in performance. Among patients with MS, obstructive sleep apnea and sleep disturbance are significantly associated with diminished visual memory, verbal memory, executive function (as reflected by response inhibition), attention, processing speed, and working memory. If sleep disorders degrade these cognitive functions, effective treatment could offer new opportunities to improve cognitive functioning in patients with MS. A commentary on this article appears in this issue on page 1489. © 2016 Associated Professional Sleep Societies, LLC.

Sleep-related memory consolidation in primary insomnia.

PubMed

Nissen, Christoph; Kloepfer, Corinna; Feige, Bernd; Piosczyk, Hannah; Spiegelhalder, Kai; Voderholzer, Ulrich; Riemann, Dieter

2011-03-01

It has been suggested that healthy sleep facilitates the consolidation of newly acquired memories and underlying brain plasticity. The authors tested the hypothesis that patients with primary insomnia (PI) would show deficits in sleep-related memory consolidation compared to good sleeper controls (GSC). The study used a four-group parallel design (n=86) to investigate the effects of 12 h of night-time, including polysomnographically monitored sleep ('sleep condition' in PI and GSC), versus 12 h of daytime wakefulness ('wake condition' in PI and GSC) on procedural (mirror tracing task) and declarative memory consolidation (visual and verbal learning task). Demographic characteristics and memory encoding did not differ between the groups at baseline. Polysomnography revealed a significantly disturbed sleep profile in PI compared to GSC in the sleep condition. Night-time periods including sleep in GSC were associated with (i) a significantly enhanced procedural and declarative verbal memory consolidation compared to equal periods of daytime wakefulness in GSC and (ii) a significantly enhanced procedural memory consolidation compared to equal periods of daytime wakefulness and night-time sleep in PI. Across retention intervals of daytime wakefulness, no differences between the experimental groups were observed. This pattern of results suggests that healthy sleep fosters the consolidation of new memories, and that this process is impaired for procedural memories in patients with PI. Future work is needed to investigate the impact of treatment on improving sleep and memory. © 2010 European Sleep Research Society.

Sleep-dependent memory consolidation in the epilepsy monitoring unit: A pilot study.

PubMed

Sarkis, Rani A; Alam, Javad; Pavlova, Milena K; Dworetzky, Barbara A; Pennell, Page B; Stickgold, Robert; Bubrick, Ellen J

2016-08-01

We sought to examine whether patients with focal epilepsy exhibit sleep dependent memory consolidation, whether memory retention rates correlated with particular aspects of sleep physiology, and how the process was affected by seizures. We prospectively recruited patients with focal epilepsy and assessed declarative memory using a task consisting of 15 pairs of colored pictures on a 5×6 grid. Patients were tested 12h after training, once after 12h of wakefulness and once after 12h that included sleep. EMG chin electrodes were placed to enable sleep scoring. The number and density of sleep spindles were assessed using a wavelet-based algorithm. Eleven patients were analyzed age 21-56years. The percentage memory retention over 12h of wakefulness was 62.7% and over 12h which included sleep 83.6% (p=0.04). Performance on overnight testing correlated with the duration of slow wave sleep (SWS) (r=+0.63, p<0.05). Three patients had seizures during the day, and 3 had nocturnal seizures. Day-time seizures did not affect retention rates, while those patients who had night time seizures had a drop in retention from an average of 92% to 60.5%. There is evidence of sleep dependent memory consolidation in patients with epilepsy which mostly correlates with the amount of SWS. Our preliminary findings suggest that nocturnal seizures likely disrupt sleep dependent memory consolidation. Findings highlight the importance of SWS in sleep dependent memory consolidation and the adverse impact of nocturnal seizures on this process. Copyright © 2016 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.

Sleep-dependent Memory Consolidation in the Epilepsy Monitoring Unit: a Pilot Study

PubMed Central

Sarkis, Rani A.; Alam, Javad; Pavlova, Milena K.; Dworetzky, Barbara A.; Pennell, Page B.; Stickgold, Robert; Bubrick, Ellen J.

2018-01-01

Objective We sought to examine whether patients with focal epilepsy exhibit sleep dependent memory consolidation, whether memory retention rates correlated with particular aspects of sleep physiology, and how the process was affected by seizures. Methods We prospectively recruited patients with focal epilepsy and assessed declarative memory using a task consisting of 15 pairs of colored pictures on a 5 × 6 grid. Patients were tested 12 hours after training, once after 12 hours of wakefulness and once after 12 hours that included sleep. EMG chin electrodes were placed to enable sleep scoring. The number and density of sleep spindles were assessed using a wavelet-based algorithm. Results Eleven patients were analyzed age 21–56 years. The percentage memory retention over 12 hours of wakefulness was 62.7% % and over 12 hours which included sleep 83.6 % (p = 0.04). Performance on overnight testing correlated with the duration of slow wave sleep (SWS) (r=+0.63, p <0.05). Three patients had seizures during the day, and another 3 had nocturnal seizures. Day-time seizures did not affect retention rates, while those patients who had night time seizures had a drop in retention from an average of 92% to 60.5%. Conclusions There is evidence of sleep dependent memory consolidation in patients with epilepsy which mostly correlates with the amount of SWS. Our preliminary findings suggest that nocturnal seizures likely disrupt sleep dependent memory consolidation. Significance Findings highlight the importance of SWS in sleep dependent memory consolidation and the adverse impact of nocturnal seizures on this process. PMID:27417054

Flurbiprofen in rapid eye movement sleep deprivation induced hyperalgesia.

PubMed

Gürel, Elif Ezgi; Ural, Keremcan; Öztürk, Gülnur; Öztürk, Levent

2014-04-10

Rapid eye movement (REM) sleep deprivation induces hyperalgesia in healthy rats. Here, we evaluated the effects of flurbiprofen, an anti-inflammatory and neuroprotective agent, on the increased thermal responses observed in REM sleep deprived rats. Forty female rats were divided into four groups following 96-hour REM sleep deprivation: intraperitoneal injections of placebo, and flurbiprofen 5 mg/kg, 15 mg/kg and 40 mg/kg were made in CONT (n=10), FBP5, FBP15 and FBP40 groups respectively. Pain threshold measurements were performed three times at baseline (0.hour), at the end of REM sleep deprivation (96.hour) and at 1 h after injections (97.hour) by hot plate and tail-flick tests. REM sleep deprivation induced a significant decrease in pain thresholds of all rats (hotplate: 0.hour vs 96.hour, 9.75±2.85 vs 5.10±2.02, p<0.001; tail flick: 0.hour vs 96.hour, 11.92±4.62 vs 7.92±5.15, p<0.001). Flurbiprofen in 15 mg/kg and 40 mg/kg doses significantly improved pain tolerance measured by tail flick test (tail flick in FBP15 and FBP40 groups: 96.hour vs 97.hour, 7.01±4.97 vs 8.34±3.61 and 5.06±1.57 vs 7.04±2.49, p<0.05 for both). 96 h of REM sleep deprivation resulted in reduced pain thresholds in both hot plate and tail flick tests. Flurbiprofen was used for the first time in a rat model of REM sleep deprivation, and it provided anti-nociceptive effects in 15 mg/kg and 40 mg/kg doses. Flurbiprofen may have the potential for treatment of painful syndromes accompanying insomnia or sleep loss. Copyright © 2014 Elsevier Inc. All rights reserved.

Sleep-wake patterns, non-rapid eye movement, and rapid eye movement sleep cycles in teenage narcolepsy.

PubMed

Xu, Xing; Wu, Huijuan; Zhuang, Jianhua; Chen, Kun; Huang, Bei; Zhao, Zhengqing; Zhao, Zhongxin

2017-05-01

To further characterize sleep disorders associated with narcolepsy, we assessed the sleep-wake patterns, rapid eye movement (REM), and non-REM (NREM) sleep cycles in Chinese teenagers with narcolepsy. A total of 14 Chinese type 1 narcoleptic patients (13.4 ± 2.6 years of age) and 14 healthy age- and sex-matched control subjects (13.6 ± 1.8 years of age) were recruited. Ambulatory 24-h polysomnography was recorded for two days, with test subjects adapting to the instruments on day one and the study data collection performed on day two. Compared with the controls, the narcoleptic patients showed a 1.5-fold increase in total sleep time over 24 h, characterized by enhanced slow-wave sleep and REM sleep. Frequent sleep-wake transitions were identified in nocturnal sleep with all sleep stages switching to wakefulness, with more awakenings and time spent in wakefulness after sleep onset. Despite eight cases of narcolepsy with sleep onset REM periods at night, the mean duration of NREM-REM sleep cycle episode and the ratio of REM/NREM sleep between patients and controls were not significantly different. Our study identified hypersomnia in teenage narcolepsy despite excessive daytime sleepiness. Sleep fragmentation extended to all sleep stages, indicating impaired sleep-wake cycles and instability of sleep stages. The limited effects on NREM-REM sleep cycles suggest the relative conservation of ultradian regulation of sleep. Copyright © 2016 Elsevier B.V. All rights reserved.

Relationships between school start time, sleep duration, and adolescent behaviors.

PubMed

Wahlstrom, Kyla L; Berger, Aaron T; Widome, Rachel

2017-06-01

The objectives were 2-fold: (1) to examine how high school start times relate to adolescent sleep duration, and (2) to test associations between sleep duration and mental health- and substance use-related issues and behaviors in teens. This study examines selected questions from survey data collected between 2010 and 2013 high school students. Respondents included more than 9000 students in grades 9 to 12 in 8 high schools in 5 school districts across the United States. The survey instrument is the 97-item Teen Sleep Habits Survey. Logistic regression models were used to calculate adjusted odds ratios and 95% confidence intervals. Because of clustering within schools and the use of repeated measures, generalized estimating equations were used to account for variance inflation. Greater sleep duration was associated with fewer reports of various mental health- and substance use-related issues and behaviors (all P values <.01). For instance, for each additional hour of sleep reported, there was a 28% reduction in the adjusted odds of a participant reporting that he or she felt "unhappy, sad, or depressed." Later wake-up times were associated with a reduction in risk for some, but not all factors. Later start times were significantly associated with greater sleep duration. Given that later start times allow for greater sleep duration and that adequate sleep duration is associated with more favorable mental health- and substance use-related issues and behaviors, it is important that school districts prioritize exploring and implementing policies, such as delayed start times, that may increase the amount of sleep of adolescent students, which is needed for their optimal development. Copyright © 2017 National Sleep Foundation. Published by Elsevier Inc. All rights reserved.

Obstructive sleep apnea exaggerates cognitive dysfunction in stroke patients.

PubMed

Zhang, Yan; Wang, Wanhua; Cai, Sijie; Sheng, Qi; Pan, Shenggui; Shen, Fang; Tang, Qing; Liu, Yang

2017-05-01

Obstructive sleep apnea (OSA) is very common in stroke survivors. It potentially worsens the cognitive dysfunction and inhibits their functional recovery. However, whether OSA independently damages the cognitive function in stroke patients is unclear. A simple method for evaluating OSA-induced cognitive impairment is also missing. Forty-four stroke patients six weeks after onset and 24 non-stroke patients with snoring were recruited for the polysomnographic study of OSA and sleep architecture. Their cognitive status was evaluated with a validated Chinese version of Cambridge Prospective Memory Test. The relationship between memory deficits and respiratory, sleeping, and dementia-related clinical variables were analyzed with correlation and multiple linear regression tests. OSA significantly and independently damaged time- and event-based prospective memory in stroke patients, although it had less power than the stroke itself. The impairment of prospective memory was correlated with increased apnea-hypopnea index, decreased minimal and mean levels of peripheral oxygen saturation, and disrupted sleeping continuity (reduced sleep efficiency and increased microarousal index). The further regression analysis identified minimal levels of peripheral oxygen saturation and sleep efficiency to be the two most important predictors for the decreased time-based prospective memory in stroke patients. OSA independently contributes to the cognitive dysfunction in stroke patients, potentially through OSA-caused hypoxemia and sleeping discontinuity. The prospective memory test is a simple but sensitive method to detect OSA-induced cognitive impairment in stroke patients. Proper therapies of OSA might improve the cognitive function and increase the life quality of stroke patients. Copyright © 2017 Elsevier B.V. All rights reserved.

Auditory attention and multiattribute decision-making during a 33 h sleep-deprivation period: mean performance and between-subject dispersions.

PubMed

Linde, L; Edland, A; Bergström, M

1999-05-01

One purpose of this study was to compare attention in the evening (22:00 h), in the late night (04:00 h), in the morning (10:00 h) and in the afternoon (16:00 h) during a period of complete wakefulness beginning at 08:00 h with a mean daytime performance without sleep deprivation. Another purpose was to investigate sleep deprivation effects on a multi-attribute decision-making task with and without time pressure. Twelve sleep-deprived male students were compared with 12 male non-sleep-deprived students. Both groups were tested five times with an auditory attention and a symbol coding task. Significant declines (p < 0.05) in mean level of performance on the auditory attention task were found at 04:00, 10:00 and 16:00 h for subjects forced to the vigil. However, the effect of the sleep deprivation manifested itself even more in increased between-subject dispersions. There were no differences between time pressure and no time pressure on the decision-making task and no significant differences between sleep-deprived and non-sleep-deprived subjects in decision strategies. In fact, the pattern of decision strategies among the sleep-deprived subject was more similar to a pattern of decision strategies typical for non-stressful conditions than the pattern of decision strategies among the non-sleep-deprived subjects. This result may have been due to the fact that the sleep loss acted as a dearouser. Here too, however, the variances differed significantly among sleep-deprived and non-sleep-deprived subjects, indicating that the sleep-deprived subjects were more variable in their decision strategy pattern than the control group.

An approach to understanding sleep and depressed mood in adolescents: person-centred sleep classification.

PubMed

Shochat, Tamar; Barker, David H; Sharkey, Katherine M; Van Reen, Eliza; Roane, Brandy M; Carskadon, Mary A

2017-12-01

Depressive mood in youth has been associated with distinct sleep dimensions, such as timing, duration and quality. To identify discrete sleep phenotypes, we applied person-centred analysis (latent class mixture models) based on self-reported sleep patterns and quality, and examined associations between phenotypes and mood in high-school seniors. Students (n = 1451; mean age = 18.4 ± 0.3 years; 648 M) completed a survey near the end of high-school. Indicators used for classification included school night bed- and rise-times, differences between non-school night and school night bed- and rise-times, sleep-onset latency, number of awakenings, naps, and sleep quality and disturbance. Mood was measured using the total score on the Center for Epidemiologic Studies-Depression Scale. One-way anova tested differences between phenotype for mood. Fit indexes were split between 3-, 4- and 5-phenotype solutions. For all solutions, between phenotype differences were shown for all indicators: bedtime showed the largest difference; thus, classes were labelled from earliest to latest bedtime as 'A' (n = 751), 'B' (n = 428) and 'C' (n = 272) in the 3-class solution. Class B showed the lowest sleep disturbances and remained stable, whereas classes C and A each split in the 4- and 5-class solutions, respectively. Associations with mood were consistent, albeit small, with class B showing the lowest scores. Person-centred analysis identified sleep phenotypes that differed in mood, such that those with the fewest depressive symptoms had moderate sleep timing, shorter sleep-onset latencies and fewer arousals. Sleep characteristics in these groups may add to our understanding of how sleep and depressed mood associate in teens. © 2017 European Sleep Research Society.

Actigraphy-defined Measures of Sleep and Movement Across the Menstrual Cycle In Midlife Menstruating Women: SWAN Sleep Study

PubMed Central

Zheng, Huiyong; Harlow, Siobán D; Kravitz, Howard M; Bromberger, Joyce; Buysse, Daniel J; Matthews, Karen A; Gold, Ellen B; Owens, Jane F; Hall, Martica

2014-01-01

Objective To evaluate patterns in actigraphy-defined sleep measures across the menstrual cycle, testing the hypothesis that sleep would be more disrupted in the premenstrual period, i.e. in the 14 days prior to menses. Methods A community-based, longitudinal study of wrist actigraphy-derived sleep measures was conducted with 163 women (58 African-American, 78 White, and 27 Chinese) of late reproductive age (mean=51.5, SD=2.0 years) from the Study of Women's Health Across the Nation (SWAN) Sleep Study. Daily measures of sleep [sleep efficiency (%) and total sleep time (minutes)] and movement during sleep [mean activity score (counts)] were characterized using wrist actigraphy across a menstrual cycle or 35 days, whichever was shorter. Data were standardized to 28 days to account for the variation of unequal cycle lengths and divided into four weekly segments for analyses. Results Sleep efficiency percentage declined gradually across the menstrual cycle, but the decline became pronounced in fourth week, the premenstrual period. Compared with third week, sleep efficiency declined by 5% (p<0.0001) and mean total sleep time was 25 minutes less (p=0.0002) in fourth week. No significant mean differences were found when comparing the means of second week versus third week. The association of weekly segments with sleep efficiency or minutes of total sleep time was modified by sociodemographic and lifestyle factors, including body mass index (BMI), race, study site, financial strain, marital status, and smoking. Conclusions Sleep varied systematically across the menstrual cycle in women of late reproductive age, including a gradual decline in sleep efficiency across all weeks, with a more marked change premenstrually during the last week of the menstrual cycle. These sleep changes may be modifiable by altering lifestyle factors. PMID:24845393

Actigraphy-defined measures of sleep and movement across the menstrual cycle in midlife menstruating women: Study of Women's Health Across the Nation Sleep Study.

PubMed

Zheng, Huiyong; Harlow, Siobán D; Kravitz, Howard M; Bromberger, Joyce; Buysse, Daniel J; Matthews, Karen A; Gold, Ellen B; Owens, Jane F; Hall, Martica

2015-01-01

This study aims to evaluate patterns in actigraphy-defined sleep measures across the menstrual cycle by testing the hypothesis that sleep would be more disrupted in the premenstrual period (ie, within the 14 d before menses). A community-based longitudinal study of wrist actigraphy-derived sleep measures was conducted in 163 (58 African American, 78 white, and 27 Chinese) late-reproductive-age (mean [SD], 51.5 [2.0] y) women from the Study of Women's Health Across the Nation Sleep Study. Daily measures of sleep (sleep efficiency [%] and total sleep time [minutes]) and movement during sleep (mean activity score [counts]) were characterized using wrist actigraphy across a menstrual cycle or 35 days, whichever was shorter. Data were standardized to 28 days to account for unequal cycle lengths and divided into four weekly segments for analyses. Sleep efficiency declined gradually across the menstrual cycle, but the decline became pronounced on the fourth week (the premenstrual period). Compared with the third week, sleep efficiency declined by 5% (P < 0.0001) and mean total sleep time was 25 minutes less (P = 0.0002) on the fourth week. We found no significant differences between the mean for the second week and the mean for the third week. The association of weekly segments with sleep efficiency or total sleep time was modified by sociodemographic and lifestyle factors, including body mass index, race, study site, financial strain, marital status, and smoking. Among late-reproductive-age women, sleep varies systematically across the menstrual cycle, including a gradual decline in sleep efficiency across all weeks, with a more marked change premenstrually during the last week of the menstrual cycle. These sleep changes may be modified by altering lifestyle factors.

Impact of sleep duration on seizure frequency in adults with epilepsy: a sleep diary study.

PubMed

Cobabe, Maurine M; Sessler, Daniel I; Nowacki, Amy S; O'Rourke, Colin; Andrews, Noah; Foldvary-Schaefer, Nancy

2015-02-01

Prolonged sleep deprivation activates epileptiform EEG abnormalities and seizures in people with epilepsy. Few studies have addressed the effect of chronic partial sleep deprivation on seizure occurrence in populations with epilepsy. We tested the primary hypothesis that partial sleep deprivation over 24- and 72-hour periods increases seizure occurrence in adults with epilepsy. Forty-four subjects completed a series of self-reported instruments, as well as 1-month sleep and seizure diaries, to characterize their sleep and quality of life. Diaries were used to determine the relationship between seizure occurrence and total sleep time 24 and 72h before seizure occurrence using random effects models and a logistic regression model fit by generalized estimating equations. A total of 237 seizures were recorded during 1295 diary days, representing 5.5±7.0 (mean±SD) seizures per month. Random effects models for 24- and 72-hour total sleep times showed no clinically or statistically significant differences in the total sleep time between preseizure periods and seizure-free periods. The average 24-hour total sleep time during preseizure 24-hour periods was 8min shorter than that during seizure-free periods (p=0.51). The average 72-hour total sleep time during preseizure periods was 20min longer than that during seizure-free periods (p=0.86). The presence of triggers was a significant predictor of seizure occurrence, with stress/anxiety noted most often as a trigger. Mean total sleep time was 9h, and subjects took an average of 12±10 naps per month, having a mean duration of 1.9±1.2h. Daytime sleepiness, fatigue, and insomnia symptoms were commonly reported. Small degrees of sleep loss were not associated with seizure occurrence in our sample of adults with epilepsy. Our results also include valuable observations of the altered sleep times and frequent napping habits of adults with refractory epilepsy and the potential contribution of these habits to quality of life and seizure control. Copyright © 2014 Elsevier Inc. All rights reserved.

Pinellia ternata (Thunb.) Makino Preparation promotes sleep by increasing REM sleep.

PubMed

Lin, Sisi; Nie, Bo; Yao, Guihong; Yang, Hui; Ye, Ren; Yuan, Zhengzhong

2018-05-15

Pinellia ternata (Thunb.) Makino Preparation (PTP) is widely used to treat insomnia in traditional Chinese medicine; however, its specific role is not clear. In this study, PTP was prepared at three concentrations. For locomotor activity tests, mice were treated with PTP and evaluated for 14 days. For polygraph recordings, mice were treated for 14 days and recorded after treatment. The main chemical constituents in PTP were identified by Ultra performance liquid chromatography/quadrupole time spectrometry (UPLC/Q-TOF-MS). The results showed that 0.9 g/mL PTP significantly reduced locomotor activity. The effect was related to the time of treatment. PTP reduced wakefulness and increased sleep in mice. Furthermore, PTP promoted sleep by increasing the number of REM sleep episodes with a duration of 64-128s and increasing the number of transitions from NREM sleep to REM sleep and from REM sleep to wakefulness. A total of 17 compounds were identified.

Earlier School Start Times as a Risk Factor for Poor School Performance: An Examination of Public Elementary Schools in the Commonwealth of Kentucky

ERIC Educational Resources Information Center

Keller, Peggy S.; Smith, Olivia A.; Gilbert, Lauren R.; Bi, Shuang; Haak, Eric A.; Buckhalt, Joseph A.

2015-01-01

Adequate sleep is essential for child learning. However, school systems may inadvertently be promoting sleep deprivation through early school start times. The current study examines the potential implications of early school start times for standardized test scores in public elementary schools in Kentucky. Associations between early school start…

The impact of diurnal sleep on the consolidation of a complex gross motor adaptation task.

PubMed

Hoedlmoser, Kerstin; Birklbauer, Juergen; Schabus, Manuel; Eibenberger, Patrick; Rigler, Sandra; Mueller, Erich

2015-02-01

Diurnal sleep effects on consolidation of a complex, ecological valid gross motor adaptation task were examined using a bicycle with an inverse steering device. We tested 24 male subjects aged between 20 and 29 years using a between-subjects design. Participants were trained to adapt to the inverse steering bicycle during 45 min. Performance was tested before (TEST1) and after (TEST2) training, as well as after a 2 h retention interval (TEST3). During retention, participants either slept or remained awake. To assess gross motor performance, subjects had to ride the inverse steering bicycle 3 × 30 m straight-line and 3 × 30 m through a slalom. Beyond riding time, we sophisticatedly measured performance accuracy (standard deviation of steering angle) in both conditions using a rotatory potentiometer. A significant decrease of accuracy during straight-line riding after nap and wakefulness was shown. Accuracy during slalom riding remained stable after wakefulness but was reduced after sleep. We found that the duration of rapid eye movement sleep as well as sleep spindle activity are negatively related with gross motor performance changes over sleep. Together these findings suggest that the consolidation of adaptation to a new steering device does not benefit from a 2 h midday nap. We speculate that in case of strongly overlearned motor patterns such as normal cycling, diurnal sleep spindles and rapid eye movement sleep might even help to protect everyday needed skills, and to rapidly forget newly acquired, interfering and irrelevant material. © 2014 The Authors. Journal of Sleep Research published by John Wiley & Sons Ltd on behalf of European Sleep Research Society.

Cognitive Performance, Sleepiness, and Mood in Partially Sleep Deprived Adolescents: The Need for Sleep Study.

PubMed

Lo, June C; Ong, Ju Lynn; Leong, Ruth L F; Gooley, Joshua J; Chee, Michael W L

2016-03-01

To investigate the effects of sleep restriction (7 nights of 5 h time in bed [TIB]) on cognitive performance, subjective sleepiness, and mood in adolescents. A parallel-group design was adopted in the Need for Sleep Study. Fifty-six healthy adolescents (25 males, age = 15-19 y) who studied in top high schools and were not habitual short sleepers were randomly assigned to Sleep Restriction (SR) or Control groups. Participants underwent a 2-w protocol consisting of 3 baseline nights (TIB = 9 h), 7 nights of sleep opportunity manipulation (TIB = 5 h for the SR and 9 h for the control groups), and 3 nights of recovery sleep (TIB = 9 h) at a boarding school. A cognitive test battery was administered three times each day. During the manipulation period, the SR group demonstrated incremental deterioration in sustained attention, working memory and executive function, increase in subjective sleepiness, and decrease in positive mood. Subjective sleepiness and sustained attention did not return to baseline levels even after 2 recovery nights. In contrast, the control group maintained baseline levels of cognitive performance, subjective sleepiness, and mood throughout the study. Incremental improvement in speed of processing, as a result of repeated testing and learning, was observed in the control group but was attenuated in the sleep-restricted participants, who, despite two recovery sleep episodes, continued to perform worse than the control participants. A week of partial sleep deprivation impairs a wide range of cognitive functions, subjective alertness, and mood even in high-performing high school adolescents. Some measures do not recover fully even after 2 nights of recovery sleep. A commentary on this article appears in this issue on page 497. © 2016 Associated Professional Sleep Societies, LLC.

Sleep and cognitive functioning in childhood: Ethnicity, socioeconomic status, and sex as moderators.

PubMed

Philbrook, Lauren E; Hinnant, J Benjamin; Elmore-Staton, Lori; Buckhalt, Joseph A; El-Sheikh, Mona

2017-07-01

We examined children's sleep at age 9 as a predictor of developmental trajectories of cognitive performance from ages 9 to 11 years. The effects of sleep on cognition are not uniform and thus we tested race/ethnicity, socioeconomic status (SES), and sex as moderators of these associations. At the first assessment, 282 children aged 9.44 years (52% boys, 65% European American [EA], 35% African American [AA]) participated. Two more waves of data collection spaced 1 year apart followed. The majority of children (63%) were living at or below the poverty line. Children's sleep was measured objectively with actigraphy and 2 well-established sleep parameters were derived: duration, indexed by sleep minutes between sleep onset and wake time, and quality, indexed by efficiency. Multiple cognitive functioning domains were examined with the Woodcock Johnson Tests of Cognitive Abilities (WJ III). Across the sample, higher sleep efficiency, but not duration, was associated with better cognitive performance. Significant moderation effects emerged. Controlling for SES, AA children scored lower on general intellectual ability and working memory (WM) at age 11 only if they experienced lower sleep efficiency at age 9. Further, boys scored lower on general abilities and processing speed (PS) at age 11 only if their sleep efficiency was lower at age 9. Findings indicate that lower sleep efficiency may contribute to lower cognitive functioning especially for AA children and boys. These vulnerabilities appear to emerge early in development and are maintained over time. Results underscore the importance of individual differences in explicating relations between sleep and children's cognitive performance. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Chronic Stress is Prospectively Associated with Sleep in Midlife Women: The SWAN Sleep Study.

PubMed

Hall, Martica H; Casement, Melynda D; Troxel, Wendy M; Matthews, Karen A; Bromberger, Joyce T; Kravitz, Howard M; Krafty, Robert T; Buysse, Daniel J

2015-10-01

Evaluate whether levels of upsetting life events measured over a 9-y period prospectively predict subjective and objective sleep outcomes in midlife women. Prospective cohort study. Four sites across the United States. 330 women (46-57 y of age) enrolled in the Study of Women's Health Across the Nation (SWAN) Sleep Study. N/A. Upsetting life events were assessed annually for up to 9 y. Trajectory analysis applied to life events data quantitatively identified three distinct chronic stress groups: low stress, moderate stress, and high stress. Sleep was assessed by self-report and in-home polysomnography (PSG) during the ninth year of the study. Multivariate analyses tested the prospective association between chronic stress group and sleep, adjusting for race, baseline sleep complaints, marital status, body mass index, symptoms of depression, and acute life events at the time of the Sleep Study. Women characterized by high chronic stress had lower subjective sleep quality, were more likely to report insomnia, and exhibited increased PSG-assessed wake after sleep onset (WASO) relative to women with low to moderate chronic stress profiles. The effect of chronic stress group on WASO persisted in the subsample of participants without baseline sleep complaints. Chronic stress is prospectively associated with sleep disturbance in midlife women, even after adjusting for acute stressors at the time of the sleep study and other factors known to disrupt sleep. These results are consistent with current models of stress that emphasize the cumulative effect of stressors on health over time. © 2015 Associated Professional Sleep Societies, LLC.

Perceived stress, disturbed sleep, and cognitive impairments in patients with work-related stress complaints: a longitudinal study.

PubMed

Eskildsen, Anita; Fentz, Hanne Nørr; Andersen, Lars Peter; Pedersen, Anders Degn; Kristensen, Simon Bang; Andersen, Johan Hviid

2017-07-01

Patients on sick leave due to work-related stress often present with cognitive impairments as well as sleep disturbances. The aim of this longitudinal study was to examine the role of perceived stress and sleep disturbances in the longitudinal development in cognitive impairments in a group of patients with prolonged work-related stress (N = 60) during a period of 12 months following initial professional care-seeking. Objective cognitive impairments (neuropsychological tests) were measured on two occasions - at initial professional care-seeking and at 12-month follow-up. Questionnaires on perceived stress, sleep disturbances, and cognitive complaints were completed seven times during the 12 months which facilitated multilevel analysis with segregation of within-person (change) and between-person (baseline level) components of the time-varying predictors (perceived stress and sleep disturbances). Change in perceived stress was associated with concurrent and subsequent change in self-reported cognitive complaints over the period of 12 months and to a lesser extent the change in performance on neuropsychological tests of processing speed from baseline to 12-month follow-up. Change in sleep disturbances was also associated with concurrent and subsequent change in self-reported cognitive complaints over the 12 months but not with change on neuropsychological test performance. Although the mechanism behind the improvement in cognitive impairments in patients with work-related stress should be further explored in future studies, the results could suggest that improvement in cognitive impairments is partly mediated by decreasing levels of perceived stress and, to a lesser extent, decreasing levels of sleep disturbances. Lay summary This study examines the role of perceived stress and sleep disturbances in respect to the development of cognitive impairments (e.g. memory and concentration) in a group of patients with work-related stress. We found that change in cognitive impairments seems to be partly explained by change in perceived stress and, to a lesser extent, sleep disturbances over time. This could suggest that cognitive impairments can be reduced by stress management interventions which aim to reduce perceived stress and sleep disturbances but future studies are needed to confirm this interpretation.

Enduring effects of perinatal nicotine exposure on murine sleep in adulthood.

PubMed

Borniger, Jeremy C; Don, Reuben F; Zhang, Ning; Boyd, R Thomas; Nelson, Randy J

2017-09-01

The long-term consequences of early life nicotine exposure are poorly defined. Approximately 8-10% of women report smoking during pregnancy, and this may promote aberrant development in the offspring. To this end, we investigated potential enduring effects of perinatal nicotine exposure on murine sleep and affective behaviors in adulthood (~13-15 wk of age) in C57Bl6j mice. Mothers received a water bottle containing 200 µg/ml nicotine bitartrate dihydrate in 2% wt/vol saccharin or pH-matched 2% saccharin with 0.2% (vol/vol) tartaric acid throughout pregnancy and before weaning. Upon reaching adulthood, offspring were tested in the open field and elevated plus maze, as well as the forced swim and sucrose anhedonia tests. Nicotine-exposed male (but not female) mice had reduced mobility in the open field, but no differences were observed in anxiety-like or depressive-like responses. Upon observing this male-specific phenotype, we further assessed sleep-wake states via wireless EEG/EMG telemetry. Following baseline recording, we assessed whether mice exposed to nicotine altered their homeostatic response to 5 h of total sleep deprivation and whether nicotine influenced responses to a powerful somnogen [i.e., lipopolysaccharides (LPS)]. Males exposed to perinatal nicotine decreased the percent time spent awake and increased time in non-rapid eye movement (NREM) sleep, without changes to REM sleep. Nicotine-exposed males also displayed exaggerated responses (increased time asleep and NREM spectral power) to sleep deprivation. Nicotine-exposed animals additionally had blunted EEG slow-wave responses to LPS administration. Together, our data suggest that perinatal nicotine exposure has long-lasting effects on normal sleep and homeostatic sleep processes into adulthood. Copyright © 2017 the American Physiological Society.

Sleep and alertness in North Sea helicopter operations.

PubMed

Simons, Ries; Wilschut, Ellen S; Valk, Pierre J L

2011-07-01

Dutch North Sea helicopter operations are characterized by multiple sector flights to offshore platforms under difficult environmental conditions. In the context of a Ministry of Transport program to improve safety levels of helicopter operations, we assessed effects of pre-duty sleep, pre-duty travel time, and workload factors on the alertness and vigilance of pilots. Data of 24 pilots comprising 224 duty days were analyzed. Pilots performed 10-min test sessions after wake up, pre-duty, halfway-duty, end-duty, and at bedtime during normal duty rosters. Test sessions included completion of a vigilance task, vigor and sleepiness ratings, and questions on sleep and operational characteristics. Pilots wore an actometer to objectify sleep data. Vigor scores were high and sleepiness levels were low during the entire flight duty periods (FDPs), while vigilance was impaired only 6.8% in the course of the FDPs. Pre-duty sleep before morning duties was 1.5 h shorter than sleep before duties starting after midday. Longer pre-duty travel time was correlated with shorter pre-duty sleep and lower vigilance levels during duty. During the FDPs, pilots maintained alertness and vigilance levels that may be considered safe in terms of alertness-related flight safety. This favorable outcome may be attributed to reasonable length of FDPs, favorable circadian start and end times of duties, sufficient opportunities for restorative pre-duty sleep, and relatively good weather conditions. Appropriate FDP scheduling is an important measure to optimize alertness of helicopter pilots who have to cope with adverse environmental conditions and limited landing and air traffic control facilities.

Decision Modeling in Sleep Apnea: The Critical Roles of Pretest Probability, Cost of Untreated Obstructive Sleep Apnea, and Time Horizon.

PubMed

Moro, Marilyn; Westover, M Brandon; Kelly, Jessica; Bianchi, Matt T

2016-03-01

Obstructive sleep apnea (OSA) is associated with increased morbidity and mortality, and treatment with positive airway pressure (PAP) is cost-effective. However, the optimal diagnostic strategy remains a subject of debate. Prior modeling studies have not consistently supported the widely held assumption that home sleep testing (HST) is cost-effective. We modeled four strategies: (1) treat no one; (2) treat everyone empirically; (3) treat those testing positive during in-laboratory polysomnography (PSG) via in-laboratory titration; and (4) treat those testing positive during HST with auto-PAP. The population was assumed to lack independent reasons for in-laboratory PSG (such as insomnia, periodic limb movements in sleep, complex apnea). We considered the third-party payer perspective, via both standard (quality-adjusted) and pure cost methods. The preferred strategy depended on three key factors: pretest probability of OSA, cost of untreated OSA, and time horizon. At low prevalence and low cost of untreated OSA, the treat no one strategy was favored, whereas empiric treatment was favored for high prevalence and high cost of untreated OSA. In-laboratory backup for failures in the at-home strategy increased the preference for the at-home strategy. Without laboratory backup in the at-home arm, the in-laboratory strategy was increasingly preferred at longer time horizons. Using a model framework that captures a broad range of clinical possibilities, the optimal diagnostic approach to uncomplicated OSA depends on pretest probability, cost of untreated OSA, and time horizon. Estimating each of these critical factors remains a challenge warranting further investigation. © 2016 American Academy of Sleep Medicine.

3-minute smartphone-based and tablet-based psychomotor vigilance tests for the assessment of reduced alertness due to sleep deprivation.

PubMed

Grant, Devon A; Honn, Kimberly A; Layton, Matthew E; Riedy, Samantha M; Van Dongen, Hans P A

2017-06-01

The psychomotor vigilance test (PVT) is widely used to measure reduced alertness due to sleep loss. Here, two newly developed, 3-min versions of the psychomotor vigilance test, one smartphone-based and the other tablet-based, were validated against a conventional 10-min laptop-based PVT. Sixteen healthy participants (ages 22-40; seven males, nine females) completed a laboratory study, which included a practice and a baseline day, a 38-h total sleep deprivation (TSD) period, and a recovery day, during which they performed the three different versions of the PVT every 3 h. For each version of the PVT, the number of lapses, mean response time (RT), and number of false starts showed statistically significant changes across the sleep deprivation and recovery days. The number of lapses on the laptop was significantly correlated with the numbers of lapses on the smartphone and tablet. The mean RTs were generally faster on the smartphone and tablet than on the laptop. All three versions of the PVT exhibited a time-on-task effect in RTs, modulated by time awake and time of day. False starts were relatively rare on all three PVTs. For the number of lapses, the effect sizes across 38 h of TSD were large for the laptop PVT and medium for the smartphone and tablet PVTs. These results indicate that the 3-min smartphone and tablet PVTs are valid instruments for measuring reduced alertness due to sleep deprivation and restored alertness following recovery sleep. The results also indicate that the loss of sensitivity on the 3-min PVTs may be mitigated by modifying the threshold defining lapses.

Sleep disturbance induces neuroinflammation and impairment of learning and memory.

PubMed

Zhu, Biao; Dong, Yuanlin; Xu, Zhipeng; Gompf, Heinrich S; Ward, Sarah A P; Xue, Zhanggang; Miao, Changhong; Zhang, Yiying; Chamberlin, Nancy L; Xie, Zhongcong

2012-12-01

Hospitalized patients can develop cognitive function decline, the mechanisms of which remain largely to be determined. Sleep disturbance often occurs in hospitalized patients, and neuroinflammation can induce learning and memory impairment. We therefore set out to determine whether sleep disturbance can induce neuroinflammation and impairment of learning and memory in rodents. Five to 6-month-old wild-type C57BL/6J male mice were used in the studies. The mice were placed in rocking cages for 24 h, and two rolling balls were present in each cage. The mice were tested for learning and memory function using the Fear Conditioning Test one and 7 days post-sleep disturbance. Neuroinflammation in the mouse brain tissues was also determined. Of the Fear Conditioning studies at one day and 7 days after sleep disturbance, twenty-four hour sleep disturbance decreased freezing time in the context test, which assesses hippocampus-dependent learning and memory; but not the tone test, which assesses hippocampus-independent learning and memory. Sleep disturbance increased pro-inflammatory cytokine IL-6 levels and induced microglia activation in the mouse hippocampus, but not the cortex. These results suggest that sleep disturbance induces neuroinflammation in the mouse hippocampus, and impairs hippocampus-dependent learning and memory in mice. Pending further studies, these findings suggest that sleep disturbance-induced neuroinflammation and impairment of learning and memory may contribute to the development of cognitive function decline in hospitalized patients. Copyright © 2012 Elsevier Inc. All rights reserved.

Microsurgical Performance After Sleep Interruption: A NeuroTouch Simulator Study.

PubMed

Micko, Alexander; Knopp, Karoline; Knosp, Engelbert; Wolfsberger, Stefan

2017-10-01

In times of the ubiquitous debate about doctors' working hour restrictions, it is still questionable if the physician's performance is impaired by high work load and long shifts. In this study, we evaluated the impact of sleep interruption on neurosurgical performance. Ten medical students and 10 neurosurgical residents were tested on the virtual-reality simulator NeuroTouch by performing an identical microsurgical task, well rested (baseline test), and after sleep interruption at night (stress test). Deviation of total score, timing, and excessive force on tissue were evaluated. In addition, vital parameters and self-assessment were analyzed. After sleep interruption, total performance score increased significantly (45.1 vs. 48.7, baseline vs. stress test, P = 0.048) while timing remained stable (10.1 vs. 10.4 minutes for baseline vs. stress test, P > 0.05) for both students and residents. Excessive force decreased in both groups during the stress test for the nondominant hand (P = 0.05). For the dominant hand, an increase of excessive force was encountered in the group of residents (P = 0.05). In contrast to their results, participants of both groups assessed their performance worse during the stress test. In our study, we found an increase of neurosurgical simulator performance in neurosurgical residents and medical students under simulated night shift conditions. Further, microsurgical dexterity remained unchanged. Based on our results and the data in the available literature, we cannot confirm that working hour restrictions will have a positive effect on neurosurgical performance. Copyright © 2017 Elsevier Inc. All rights reserved.

Declarative and Non-declarative Memory Consolidation in Children with Sleep Disorder.

PubMed

Csábi, Eszter; Benedek, Pálma; Janacsek, Karolina; Zavecz, Zsófia; Katona, Gábor; Nemeth, Dezso

2015-01-01

Healthy sleep is essential in children's cognitive, behavioral, and emotional development. However, remarkably little is known about the influence of sleep disorders on different memory processes in childhood. Such data could give us a deeper insight into the effect of sleep on the developing brain and memory functions and how the relationship between sleep and memory changes from childhood to adulthood. In the present study we examined the effect of sleep disorder on declarative and non-declarative memory consolidation by testing children with sleep-disordered breathing (SDB) which is characterized by disrupted sleep structure. We used a story recall task to measure declarative memory and Alternating Serial Reaction time (ASRT) task to assess non-declarative memory. This task enables us to measure two aspects of non-declarative memory, namely general motor skill learning and sequence-specific learning. There were two sessions: a learning phase and a testing phase, separated by a 12 h offline period with sleep. Our data showed that children with SDB exhibited a generally lower declarative memory performance both in the learning and testing phase; however, both the SDB and control groups exhibited retention of the previously recalled items after the offline period. Here we showed intact non-declarative consolidation in SDB group in both sequence-specific and general motor skill. These findings suggest that sleep disorders in childhood have a differential effect on different memory processes (online vs. offline) and give us insight into how sleep disturbances affects developing brain.

Declarative and Non-declarative Memory Consolidation in Children with Sleep Disorder

PubMed Central

Csábi, Eszter; Benedek, Pálma; Janacsek, Karolina; Zavecz, Zsófia; Katona, Gábor; Nemeth, Dezso

2016-01-01

Healthy sleep is essential in children’s cognitive, behavioral, and emotional development. However, remarkably little is known about the influence of sleep disorders on different memory processes in childhood. Such data could give us a deeper insight into the effect of sleep on the developing brain and memory functions and how the relationship between sleep and memory changes from childhood to adulthood. In the present study we examined the effect of sleep disorder on declarative and non-declarative memory consolidation by testing children with sleep-disordered breathing (SDB) which is characterized by disrupted sleep structure. We used a story recall task to measure declarative memory and Alternating Serial Reaction time (ASRT) task to assess non-declarative memory. This task enables us to measure two aspects of non-declarative memory, namely general motor skill learning and sequence-specific learning. There were two sessions: a learning phase and a testing phase, separated by a 12 h offline period with sleep. Our data showed that children with SDB exhibited a generally lower declarative memory performance both in the learning and testing phase; however, both the SDB and control groups exhibited retention of the previously recalled items after the offline period. Here we showed intact non-declarative consolidation in SDB group in both sequence-specific and general motor skill. These findings suggest that sleep disorders in childhood have a differential effect on different memory processes (online vs. offline) and give us insight into how sleep disturbances affects developing brain. PMID:26793090

Predictors of adherence to a brief behavioral insomnia intervention: daily process analysis.

PubMed

Ruiter Petrov, Megan E; Lichstein, Kenneth L; Huisingh, Carrie E; Bradley, Laurence A

2014-05-01

Behavioral interventions for insomnia are effective in improving sleep, yet adherence is variable, and predictors of adherence have not been consistently replicated. The relationships between daily variations in state factors at the initiation of treatment and adherence have not been investigated. Using 2-week, self-report online logs, this study determined, among 53 college students with probable insomnia, the associations of pretreatment factors and daily factors during treatment on daily variations in adherence to one session of behavioral treatments for insomnia. These treatments included stimulus control therapy (SCT), sleep restriction therapy (SRT), and sleep hygiene (SH). Low self-efficacy was associated with poorer SCT and SH adherence. Participants with a "bed partner or pet" at least some of the time had better SCT adherence. Greater total sleep time and poorer sleep quality were associated with poor SCT and SRT adherence the following night. Greater sleep efficiency was related to greater next night SCT and SRT adherence. Alcohol consumption was related to poorer SRT and SH adherence the following night. Future studies should test the replicability of these findings. Adherence trials may want to test whether discouraging alcohol intake, enhancing treatment-related self-efficacy, and monitoring and providing feedback on sleep, early in treatment, affects adherence. Copyright © 2014. Published by Elsevier Ltd.

Sleep, its subjective perception, and daytime performance in insomniacs with a pattern of alpha sleep.

PubMed

Schneider-Helmert, D; Kumar, A

1995-01-15

Intrusion of alpha activity, an electroencephalographic (EEG) pattern typical for wakefulness, into sleep stages has repeatedly been described and investigated in various populations. Some studies suggested that it is a less deep and restorative sleep, but others did not support this interpretation. The present study was carried out to collect ample data on neurophysiology and subjective experience of sleep and on daytime cognitive performance to clarify this point. A sample of 128 primary insomniacs was investigated with polysomnography (PSG) that was submitted to a computerized, automatic analysis of alpha activity during sleep. It yielded two groups of 64 Ss each with a normal, that is, nonalpha sleep EEG and with alpha-sleep, respectively. Contrasting the two groups for PSG showed that alpha sleep Ss had significantly more stage 4 and a (nonsignificant) tendency for more awakenings. Subjectively, they largely underestimated intermittent wake time and consequently overestimated sleep duration by 50 min. The performance test battery showed a difference in one test only, that is, a better short-term memory function by alpha sleep Ss. In conclusion, there was no result supporting the assumption that alpha sleep is less restorative, but a significant lack of perception of intermittent awakenings during night sleep by alpha sleep Ss was found. The authors propose an explanation and point to the implications this misperception might have for the clinician.

A global quantification of “normal” sleep schedules using smartphone data

PubMed Central

Walch, Olivia J.; Cochran, Amy; Forger, Daniel B.

2016-01-01

The influence of the circadian clock on sleep scheduling has been studied extensively in the laboratory; however, the effects of society on sleep remain largely unquantified. We show how a smartphone app that we have developed, ENTRAIN, accurately collects data on sleep habits around the world. Through mathematical modeling and statistics, we find that social pressures weaken and/or conceal biological drives in the evening, leading individuals to delay their bedtime and shorten their sleep. A country’s average bedtime, but not average wake time, predicts sleep duration. We further show that mathematical models based on controlled laboratory experiments predict qualitative trends in sunrise, sunset, and light level; however, these effects are attenuated in the real world around bedtime. Additionally, we find that women schedule more sleep than men and that users reporting that they are typically exposed to outdoor light go to sleep earlier and sleep more than those reporting indoor light. Finally, we find that age is the primary determinant of sleep timing, and that age plays an important role in the variability of population-level sleep habits. This work better defines and personalizes “normal” sleep, produces hypotheses for future testing in the laboratory, and suggests important ways to counteract the global sleep crisis. PMID:27386531

A Novel Approach to Prediction of Mild Obstructive Sleep Disordered Breathing in a Population-Based Sample: The Sleep Heart Health Study

PubMed Central

Caffo, Brian; Diener-West, Marie; Punjabi, Naresh M.; Samet, Jonathan

2010-01-01

This manuscript considers a data-mining approach for the prediction of mild obstructive sleep disordered breathing, defined as an elevated respiratory disturbance index (RDI), in 5,530 participants in a community-based study, the Sleep Heart Health Study. The prediction algorithm was built using modern ensemble learning algorithms, boosting in specific, which allowed for assessing potential high-dimensional interactions between predictor variables or classifiers. To evaluate the performance of the algorithm, the data were split into training and validation sets for varying thresholds for predicting the probability of a high RDI (≥ 7 events per hour in the given results). Based on a moderate classification threshold from the boosting algorithm, the estimated post-test odds of a high RDI were 2.20 times higher than the pre-test odds given a positive test, while the corresponding post-test odds were decreased by 52% given a negative test (sensitivity and specificity of 0.66 and 0.70, respectively). In rank order, the following variables had the largest impact on prediction performance: neck circumference, body mass index, age, snoring frequency, waist circumference, and snoring loudness. Citation: Caffo B; Diener-West M; Punjabi NM; Samet J. A novel approach to prediction of mild obstructive sleep disordered breathing in a population-based sample: the Sleep Heart Health Study. SLEEP 2010;33(12):1641-1648. PMID:21120126

Pain Sensitivity and Recovery From Mild Chronic Sleep Loss

PubMed Central

Roehrs, Timothy A.; Harris, Erica; Randall, Surilla; Roth, Thomas

2012-01-01

Study Objectives: To determine whether an extended bedtime in sleepy and otherwise healthy volunteers would increase alertness and thereby also reduce pain sensitivity. Setting: Outpatient with sleep laboratory assessments. Participants and Interventions: Healthy volunteers (n = 18), defined as having an average daily sleep latency on the Multiple Sleep Latency Test (MSLT) < 8 min, were randomized to 4 nights of extended bedtime (10 hr) (EXT) or 4 nights of their diary-reported habitual bedtimes (HAB). On day 1 and day 4 they received a standard MSLT (10:00, 12:00, 14:00, and 16:00 hr) and finger withdrawal latency pain testing to a radiant heat stimulus (10:30 and 14:30 hr). Results: During the four experimental nights the EXT group slept 1.8 hr per night more than the HAB group and average daily sleep latency on the MSLT increased in the EXT group, but not the HAB group. Similarly, finger withdrawal latency was increased (pain sensitivity was reduced) in the EXT group but not the HAB group. The nightly increase in sleep time during the four experimental nights was correlated with the improvement in MSLT, which in turn was correlated with reduced pain sensitivity. Conclusions: These are the first data to show that an extended bedtime in mildly sleepy healthy adults, which resulted in increased sleep time and reduced sleepiness, reduces pain sensitivity. Citation: Roehrs TA; Harris E; Randall S; Roth T. Pain sensitivity and recovery from mild chronic sleep loss. SLEEP 2012;35(12):1667-1672. PMID:23204609

Development of sleep monitoring system for observing the effect of the room ambient toward the quality of sleep

NASA Astrophysics Data System (ADS)

Saad, W. H. M.; Khoo, C. W.; Rahman, S. I. Ab; Ibrahim, M. M.; Saad, N. H. M.

2017-06-01

Getting enough sleep at the right times can help in improving quality of life and protect mental and physical health. This study proposes a portable sleep monitoring device to determine the relationship between the room ambient and quality of sleep. Body condition parameter such as heart rate, body temperature and body movement was used to determine quality of sleep and Audio/video-based monitoring system. The functionality test on all sensors is carried out to make sure that all sensors is working properly. The functionality of the overall system is designed for a better experience with a very minimal intervention to the user. The simple test on the body condition (body temperature and heart rate) while asleep with several different ambient parameters (humidity, brightness and temperature) are varied and the result shows that someone has a better sleep in a dark and colder ambient. This can prove by lower body temperature and lower heart rate.

Do nurses who work in a fair organization sleep and perform better and why? Testing potential psychosocial mediators of organizational justice.

PubMed

Hietapakka, Laura; Elovainio, Marko; Heponiemi, Tarja; Presseau, Justin; Eccles, Martin; Aalto, Anna-Mari; Pekkarinen, Laura; Kuokkanen, Liisa; Sinervo, Timo

2013-10-01

We examined whether organizational justice is associated with sleep quality and performance in a population-based sample of 1,729 Finnish registered nurses working full time. In addition, we tested psychological mechanisms mediating the potential association. The results of multivariate linear regression analyses showed higher organizational justice to be associated with fewer sleeping problems (β values range from -.20 to -.11) and higher self-reported performance (β values range from .05 to .35). Furthermore, psychological distress (related to the psychological stress model) and job involvement (related to the psychosocial resource model) mediated the association between organizational justice and sleep. Sleeping problems partly mediated the association between organizational justice and performance. Psychological distress explained 51% to 83% and job involvement explained 10% to 15% of the total effects of justice variables on sleeping problems. The findings provide support for the psychological stress model and offer practical implications for reducing nurses' sleeping problems.

Dim light at night does not disrupt timing or quality of sleep in mice.

PubMed

Borniger, Jeremy C; Weil, Zachary M; Zhang, Ning; Nelson, Randy J

2013-10-01

Artificial nighttime illumination has recently become commonplace throughout the world; however, in common with other animals, humans have not evolved in the ecological context of chronic light at night. With prevailing evidence linking the circadian, endocrine, immune, and metabolic systems, understanding these relationships is important to understanding the etiology and progression of several diseases. To eliminate the covariate of sleep disruption in light at night studies, researchers often use nocturnal animals. However, the assumption that light at night does not affect sleep in nocturnal animals remains unspecified. To test the effects of light at night on sleep, we maintained Swiss-Webster mice in standard light/dark (LD) or dim light at night (DLAN) conditions for 8-10 wks and then measured electroencephalogram (EEG) and electromyogram (EMG) biopotentials via wireless telemetry over the course of two consecutive days to determine differences in sleep timing and homeostasis. Results show no statistical differences in total percent time, number of episodes, maximum or average episode durations in wake, slow-wave sleep (SWS), or rapid eye movement (REM) sleep. No differences were evident in SWS delta power, an index of sleep drive, between groups. Mice kept in DLAN conditions showed a relative increase in REM sleep during the first few hours after the dark/light transition. Both groups displayed normal 24-h circadian rhythms as measured by voluntary running wheel activity. Groups did not differ in body mass, but a marked negative correlation of body mass with percent time spent awake and a positive correlation of body mass with time spent in SWS was evident. Elevated body mass was also associated with shorter maximum wake episode durations, indicating heavier animals had more trouble remaining in the wake vigilance state for extended periods of time. Body mass did not correlate with activity levels, nor did activity levels correlate with time spent in different sleep states. These data indicate that heavier animals tend to sleep more, potentially contributing to further weight gain. We conclude that chronic DLAN exposure does not significantly affect sleep timing or homeostasis in mice, supporting the use of dim light with nocturnal rodents in chronobiology research to eliminate the possible covariate of sleep disruption.

[Improved methods for monitoring sleep state and respiratory rhythm in freely moving rats].

PubMed

Wang, Qi-Min; Dong, Hui; Zhang, Cheng; Zhang, Yong-He; Ma, Jing; Wang, Guang-Fa

2014-01-01

To improve the method for monitoring sleep state and respiratory rhythm of SD rats, providing a solution for rats' chewing on the wires, signal loss and instability problems in the animal model of sleep apnea syndrome (SAS). We improved monitoring electrodes of both electrocorticogram (ECoG) and electromyogram (EMG), signal circuit and animal operation. Operation time was shortened and wound exposure time was reduced, which made it easier for postoperative recovery. The ECoG and EMG signals were more stable with sharp image, and signal circuit lines had better conductivity and material durability, achieving continuous monitoring for a long time and high success rate. We could precisely distinguish the sleep wake state and the sleep apnea events in rats according to these signals. The improved method is more reliable and practical to test the small animal model of SAS, and is more easily to operate and the signals are more stable.

Skylab sleep monitoring experiment (experiment M133)

NASA Technical Reports Server (NTRS)

Frost, J. D., Jr.

1975-01-01

A summary of the conceptual design of the Skylab sleep monitoring experiment and a comprehensive compilation of the data-analysis results from the three Skylab missions is presented. One astronaut was studied per flight, electroencephalographic, electro-oculographic, and headmotion signals acquired during sleep by use of an elastic recording cap containing sponge electrodes and an attached miniature preamplifier/accelerometer unit are shown. A control-panel assembly, mounted in the sleep compartment, tested electrodes, preserved analog signals, and automatically analyzed data in real time (providing a telemetered indication of sleep stage). Results indicate that men are able to obtain adequate sleep in regularly scheduled eight-hour rest periods during extended space missions.

Dynamic Circadian Modulation in a Biomathematical Model for the Effects of Sleep and Sleep Loss on Waking Neurobehavioral Performance

PubMed Central

McCauley, Peter; Kalachev, Leonid V.; Mollicone, Daniel J.; Banks, Siobhan; Dinges, David F.; Van Dongen, Hans P. A.

2013-01-01

Recent experimental observations and theoretical advances have indicated that the homeostatic equilibrium for sleep/wake regulation—and thereby sensitivity to neurobehavioral impairment from sleep loss—is modulated by prior sleep/wake history. This phenomenon was predicted by a biomathematical model developed to explain changes in neurobehavioral performance across days in laboratory studies of total sleep deprivation and sustained sleep restriction. The present paper focuses on the dynamics of neurobehavioral performance within days in this biomathematical model of fatigue. Without increasing the number of model parameters, the model was updated by incorporating time-dependence in the amplitude of the circadian modulation of performance. The updated model was calibrated using a large dataset from three laboratory experiments on psychomotor vigilance test (PVT) performance, under conditions of sleep loss and circadian misalignment; and validated using another large dataset from three different laboratory experiments. The time-dependence of circadian amplitude resulted in improved goodness-of-fit in night shift schedules, nap sleep scenarios, and recovery from prior sleep loss. The updated model predicts that the homeostatic equilibrium for sleep/wake regulation—and thus sensitivity to sleep loss—depends not only on the duration but also on the circadian timing of prior sleep. This novel theoretical insight has important implications for predicting operator alertness during work schedules involving circadian misalignment such as night shift work. Citation: McCauley P; Kalachev LV; Mollicone DJ; Banks S; Dinges DF; Van Dongen HPA. Dynamic circadian modulation in a biomathematical model for the effects of sleep and sleep loss on waking neurobehavioral performance. SLEEP 2013;36(12):1987-1997. PMID:24293775

Sleep restriction may lead to disruption in physiological attention and reaction time.

PubMed

Choudhary, Arbind Kumar; Kishanrao, Sadawarte Sahebrao; Dadarao Dhanvijay, Anup Kumar; Alam, Tanwir

2016-01-01

Sleepiness is the condition where for some reason fails to go into a sleep state and will have difficulty in remaining awake even while carrying out activities. Sleep restriction occurs when an individual fails to get enough sleep due to high work demands. The mechanism between sleep restriction and underlying brain physiology deficits is not well assumed. The objective of the present study was to investigate the mental attention (P300) and reaction time [visual (VRT) and auditory (ART)] among night watchmen, at subsequent; first (1st) day, fourth (4th) day and seventh (7th) day of restricted sleep period. After exclusion and inclusion criteria, the study was performed among 50 watchmen (age=18-35 years) (n=50) after providing written informed consent and divided into two group. Group I-(Normal sleep) (n=28) working in day time and used to have normal sleep in night (≥8 h); Group II-(Restricted sleep) (n=22) - working in night time and used to have less sleep in night (≤3 h). Statistical significance between the different groups was determined by the independent student ' t ' test and the significance level was fixed at p≤0.05. We observed that among all normal and restricted sleep watchmen there was not any significant variation in Karolinska Sleepiness Scale (KSS) score, VRT and ART, along with latency and amplitude of P300 on 1st day of restricted sleep. However at subsequent on 4th day and 7th day of restricted sleep, there was significant increase in (KSS)score, and prolongation of VRT and ART as well as alteration in latency and amplitude of P300 wave in restricted sleep watchmen when compare to normal sleep watchmen. The present finding concludes that loss of sleep has major impact in dynamic change in mental attention and reaction time among watchmen employed in night shift. Professional regulations and work schedules should integrate sleep schedules before and during the work period as an essential dimension for their healthy life.

Melanopsin gene variations interact with season to predict sleep onset and chronotype.

PubMed

Roecklein, Kathryn A; Wong, Patricia M; Franzen, Peter L; Hasler, Brant P; Wood-Vasey, W Michael; Nimgaonkar, Vishwajit L; Miller, Megan A; Kepreos, Kyle M; Ferrell, Robert E; Manuck, Stephen B

2012-10-01

The human melanopsin gene has been reported to mediate risk for seasonal affective disorder (SAD), which is hypothesized to be caused by decreased photic input during winter when light levels fall below threshold, resulting in differences in circadian phase and/or sleep. However, it is unclear if melanopsin increases risk of SAD by causing differences in sleep or circadian phase, or if those differences are symptoms of the mood disorder. To determine if melanopsin sequence variations are associated with differences in sleep-wake behavior among those not suffering from a mood disorder, the authors tested associations between melanopsin gene polymorphisms and self-reported sleep timing (sleep onset and wake time) in a community sample (N = 234) of non-Hispanic Caucasian participants (age 30-54 yrs) with no history of psychological, neurological, or sleep disorders. The authors also tested the effect of melanopsin variations on differences in preferred sleep and activity timing (i.e., chronotype), which may reflect differences in circadian phase, sleep homeostasis, or both. Daylength on the day of assessment was measured and included in analyses. DNA samples were genotyped for melanopsin gene polymorphisms using fluorescence polarization. P10L genotype interacted with daylength to predict self-reported sleep onset (interaction p < .05). Specifically, sleep onset among those with the TT genotype was later in the day when individuals were assessed on longer days and earlier in the day on shorter days, whereas individuals in the other genotype groups (i.e., CC and CT) did not show this interaction effect. P10L genotype also interacted in an analogous way with daylength to predict self-reported morningness (interaction p < .05). These results suggest that the P10L TT genotype interacts with daylength to predispose individuals to vary in sleep onset and chronotype as a function of daylength, whereas other genotypes at P10L do not seem to have effects that vary by daylength. A better understanding of how melanopsin confers heightened responsivity to daylength may improve our understanding of a broad range of behavioral responses to light (i.e., circadian, sleep, mood) as well as the etiology of disorders with seasonal patterns of recurrence or exacerbation.

Sleep disturbance and neurobehavioral performance among postpartum women.

PubMed

Insana, Salvatore P; Williams, Kayla B; Montgomery-Downs, Hawley E

2013-01-01

Sleep disturbances cause neurobehavioral performance and daytime functioning impairments. Postpartum women experience high levels of sleep disturbance. Thus, the study objective was to describe and explore the relation between neurobehavioral performance and sleep among women during the early postpartum period. Longitudinal field-based study. There were 70 primiparous women and nine nulliparous women in a control group. None. During their first 12 postpartum weeks, 70 primiparous women wore continuous wrist actigraphy to objectively monitor their sleep. Each morning they self-administered the psychomotor vigilance test (PVT) to index their neurobehavioral performance. Nine nulliparous women in a control group underwent the same protocol for 12 continuous weeks. Postpartum PVT mean reciprocal (1/RT) reaction time did not differ from that of women in the control group at postpartum week 2, but then worsened over time. Postpartum slowest 10% 1/RT PVT reaction time was significantly worse than that of women in the control group at all weeks. Despite improvements in postpartum sleep, neurobehavioral performance continued to worsen from week 2 through the end of the study. Across the first 12 postpartum weeks, PVT measures were more frequently associated with percent sleep compared with total sleep time, highlighting the deleterious consequences of sleep disruption on maternal daytime functioning throughout the early postpartum period. Worsened maternal neurobehavioral performance across the first 12 postpartum weeks may have been influenced by the cumulative effects of sleep disturbance. These results can inform future work to identify the particular sleep profiles that could be primary intervention targets to improve daytime functioning among postpartum women, and indicate need for further research on the effectiveness of family leave policies. The time when postpartum women return to control-level daytime functioning is unknown.

[Psychological results of mental performance in sleep deprivation].

PubMed

Dahms, P; Schaad, G; Gorges, W; von Restorff, W

1996-01-01

To quantify the effects of sleep periods that have different lengths of time during continuous operations (CONOPS) 2 independent groups of subjects performed several cognitive tasks for 3 days. The 72 h trial period contained three 60-min sleep periods for the 10 subjects of the experimental group and three sleep periods of 4 h each for the 14 subjects of the control group. With the exception of only one subtest the statistical analyses of the test results of the 2 groups show no significant differences in cognitive performance. It is suggested that high motivation is responsible for comparable performance of the subjects, which was essentially obtained by a monetary pay system for successful test performance.

A cross-cultural comparison of sleep duration between US And Australian adolescents: the effect of school start time, parent-set bedtimes, and extracurricular load.

PubMed

Short, Michelle A; Gradisar, Michael; Lack, Leon C; Wright, Helen R; Dewald, Julia F; Wolfson, Amy R; Carskadon, Mary A

2013-06-01

To test whether sleep duration on school nights differs between adolescents in Australia and the United States and, if so, whether this difference is explained by cultural differences in school start time, parental involvement in setting bedtimes, and extracurricular commitments. Three hundred eighty-five adolescents aged 13 to 18 years (M = 15.57, SD = 0.95; 60% male) from Australia and 302 adolescents aged 13 to 19 years (M = 16.03, SD = 1.19; 35% male) from the United States. Adolescents completed the School Sleep Habits Survey during class time, followed by an 8-day sleep diary. After controlling for age and gender, Australian adolescents obtained an average of 47 minutes more sleep per school night than those in the United States. Australian adolescents were more likely to have a parent-set bedtime (17.5% vs. 6.8%), have a later school start time (8:32 a.m. vs. 7:45 a.m.), and spend less time per day on extracurricular commitments (1 h 37 min vs. 2 h 41 min) than their U.S. peers. The mediating factors of parent-set bedtimes, later school start times, and less time spent on extracurricular activities were significantly associated with more total sleep. In addition to biological factors, extrinsic cultural factors significantly affect adolescent sleep. The present study highlights the importance of a cross-cultural, ecological approach and the impact of early school start times, lack of parental limit setting around bedtimes, and extracurricular load in limiting adolescent sleep.

Maximizing Sensitivity of the Psychomotor Vigilance Test (PVT) to Sleep Loss

PubMed Central

Basner, Mathias; Dinges, David F.

2011-01-01

Study Objectives: The psychomotor vigilance test (PVT) is among the most widely used measures of behavioral alertness, but there is large variation among published studies in PVT performance outcomes and test durations. To promote standardization of the PVT and increase its sensitivity and specificity to sleep loss, we determined PVT metrics and task durations that optimally discriminated sleep deprived subjects from alert subjects. Design: Repeated-measures experiments involving 10-min PVT assessments every 2 h across both acute total sleep deprivation (TSD) and 5 days of chronic partial sleep deprivation (PSD). Setting: Controlled laboratory environment. Participants: 74 healthy subjects (34 female), aged 22–45 years. Interventions: TSD experiment involving 33 h awake (N = 31 subjects) and a PSD experiment involving 5 nights of 4 h time in bed (N = 43 subjects). Measurements and Results: In a paired t-test paradigm and for both TSD and PSD, effect sizes of 10 different PVT performance outcomes were calculated. Effect sizes were high for both TSD (1.59–1.94) and PSD (0.88–1.21) for PVT metrics related to lapses and to measures of psychomotor speed, i.e., mean 1/RT (response time) and mean slowest 10% 1/RT. In contrast, PVT mean and median RT outcomes scored low to moderate effect sizes influenced by extreme values. Analyses facilitating only portions of the full 10-min PVT indicated that for some outcomes, high effect sizes could be achieved with PVT durations considerably shorter than 10 min, although metrics involving lapses seemed to profit from longer test durations in TSD. Conclusions: Due to their superior conceptual and statistical properties and high sensitivity to sleep deprivation, metrics involving response speed and lapses should be considered primary outcomes for the 10-min PVT. In contrast, PVT mean and median metrics, which are among the most widely used outcomes, should be avoided as primary measures of alertness. Our analyses also suggest that some shorter-duration PVT versions may be sensitive to sleep loss, depending on the outcome variable selected, although this will need to be confirmed in comparative analyses of separate duration versions of the PVT. Using both sensitive PVT metrics and optimal test durations maximizes the sensitivity of the PVT to sleep loss and therefore potentially decreases the sample size needed to detect the same neurobehavioral deficit. We propose criteria to better standardize the 10-min PVT and facilitate between-study comparisons and meta-analyses. Citation: Basner M; Dinges DF. Maximizing sensitivity of the psychomotor vigilance test (PVT) to sleep loss. SLEEP 2011;34(5):581-591. PMID:21532951

Cognitive Performance, Sleepiness, and Mood in Partially Sleep Deprived Adolescents: The Need for Sleep Study

PubMed Central

Lo, June C.; Ong, Ju Lynn; Leong, Ruth L.F.; Gooley, Joshua J.; Chee, Michael W.L.

2016-01-01

Study Objectives: To investigate the effects of sleep restriction (7 nights of 5 h time in bed [TIB]) on cognitive performance, subjective sleepiness, and mood in adolescents. Methods: A parallel-group design was adopted in the Need for Sleep Study. Fifty-six healthy adolescents (25 males, age = 15–19 y) who studied in top high schools and were not habitual short sleepers were randomly assigned to Sleep Restriction (SR) or Control groups. Participants underwent a 2-w protocol consisting of 3 baseline nights (TIB = 9 h), 7 nights of sleep opportunity manipulation (TIB = 5 h for the SR and 9 h for the control groups), and 3 nights of recovery sleep (TIB = 9 h) at a boarding school. A cognitive test battery was administered three times each day. Results: During the manipulation period, the SR group demonstrated incremental deterioration in sustained attention, working memory and executive function, increase in subjective sleepiness, and decrease in positive mood. Subjective sleepiness and sustained attention did not return to baseline levels even after 2 recovery nights. In contrast, the control group maintained baseline levels of cognitive performance, subjective sleepiness, and mood throughout the study. Incremental improvement in speed of processing, as a result of repeated testing and learning, was observed in the control group but was attenuated in the sleep-restricted participants, who, despite two recovery sleep episodes, continued to perform worse than the control participants. Conclusions: A week of partial sleep deprivation impairs a wide range of cognitive functions, subjective alertness, and mood even in high-performing high school adolescents. Some measures do not recover fully even after 2 nights of recovery sleep. Commentary: A commentary on this article appears in this issue on page 497. Citation: Lo JC, Ong JL, Leong RL, Gooley JJ, Chee MW. Cognitive performance, sleepiness, and mood in partially sleep deprived adolescents: the need for sleep study. SLEEP 2016;39(3):687–698. PMID:26612392

Basic psychological need experiences, fatigue, and sleep in individuals with unexplained chronic fatigue.

PubMed

Campbell, Rachel; Tobback, Els; Delesie, Liesbeth; Vogelaers, Dirk; Mariman, An; Vansteenkiste, Maarten

2017-12-01

Grounded in self-determination theory, this study tested the hypothesis that the satisfaction and frustration of the psychological needs for autonomy, competence, and relatedness would relate to fatigue and subjective and objective sleep parameters, with stress and negative sleep cognitions playing an explanatory role in these associations. During a stay at a sleep laboratory in Belgium, individuals with unexplained chronic fatigue (N = 160; 78% female) underwent polysomnography and completed a questionnaire at 3 different points in time (i.e., after arrival in the sleep lab, before bedtime, and the following morning) that assessed their need-based experiences and stress during the previous week, fatigue during the preceding day, and sleep-related cognitions and sleep during the previous night. Results indicated that need frustration related to higher stress, which in turn, related to higher evening fatigue. Need frustration also related to poorer subjective sleep quality and shorter sleep duration, as indicated by both subjective and objective shorter total sleep time and subjective (but not objective) longer sleep latency. These associations were accounted for by stress and negative sleep cognitions. These findings suggest that health care professionals working with individuals with unexplained chronic fatigue may consider focusing on basic psychological needs within their therapeutic approach. Copyright © 2017 John Wiley & Sons, Ltd.

Neuropsychological disorders related to interictal epileptic discharges during sleep in benign epilepsy of childhood with centrotemporal or Rolandic spikes.

PubMed

Baglietto, M G; Battaglia, F M; Nobili, L; Tortorelli, S; De Negri, E; Calevo, M G; Veneselli, E; De Negri, M

2001-06-01

Nine children (five males, four females; age range 6 years 1 month to 11 years 1 month) affected by benign epilepsy of childhood with centrotemporal or Rolandic spikes (BECRS) with EEG evidence of marked activation of interictal epileptic discharges (IEDs) during sleep, and nine unaffected control children matched for age, sex, and socioeconomic status, were enrolled in a prospective study. At the time of detection of IED activation during sleep, patients showed a mean Full-Scale IQ score within the normal range, but significantly below that of control participants; neuropsychological assessment revealed disorders in visuospatial short-term memory (Corsi's Block Tapping Test), attention, and cognitive flexibility (Trail Making Test and Stroop Color-Word Test), picture naming, and fluency (Benton's Naming Test and Word Fluency), visuoperceptual skill (Ghent-Poppelreuter and Street Gestalt Completion Tests) and visuomotor coordination (Bender Test). After detection of IED activation during sleep, children were followed up for 2 years. At the time of IED remission (T1), neuropsychological re-evaluation showed a notable increase in IQ score and a significant improvement (t-test: p<0.007) in visuomotor coordination, non-verbal short-term memory, sustained attention and mental flexibility, picture naming, and visual-perceptual performance. At T1, patients' performance did not differ from the controls (Mann-Whitney U test).

Nintendo Wii Fit-Based Sleepiness Testing is Not Impaired by Contagious Sleepiness.

PubMed

Tietäväinen, Aino; Kuvaldina, Maria; Hæggström, Edward

2018-06-01

Sleep deprivation may cause accidents, and it has deteriorating effects on health. A measurement of postural steadiness by a portable and affordable Nintendo Wii Fit balance board can be used to quantify a person's alertness. At work, people are under the influence of their environment-often other people-that may affect their alertness. This work investigates whether sleep deprivation among people is "contagious," as quantified by sway measures. We measured 21 volunteers' postural steadiness while alert and sleep deprived. During the measurements, a screen placed in front of the participants showed a footage of either alert or sleep-deprived faces. We found a significant difference between the day time and night time steadiness, but found no effect resulting from watching footage of sleep-deprived people. This finding shows that a posturographic sleepiness tester quantifies physiological sleep deprivation, and is insensitive to the influence of social factors.

Intermittent fasting during Ramadan: does it affect sleep?

PubMed

Bahammam, Ahmed S; Almushailhi, Khalid; Pandi-Perumal, Seithikurippu R; Sharif, Munir M

2014-02-01

Islamic intermittent fasting is distinct from regular voluntary or experimental fasting. We hypothesised that if a regimen of a fixed sleep-wake schedule and a fixed caloric intake is followed during intermittent fasting, the effects of fasting on sleep architecture and daytime sleepiness will be minimal. Therefore, we designed this study to objectively assess the effects of Islamic intermittent fasting on sleep architecture and daytime sleepiness. Eight healthy volunteers reported to the Sleep Disorders Centre on five occasions for polysomnography and multiple sleep latency tests: (1) during adaptation; (2) 3 weeks before Ramadan, after having performed Islamic fasting for 1 week (baseline fasting); (3) 1 week before Ramadan (non-fasting baseline); (4) 2 weeks into Ramadan (Ramadan); and (5) 2 weeks after Ramadan (non-fasting; Recovery). Daytime sleepiness was assessed using the Epworth Sleepiness Scale and the multiple sleep latency test. The participants had a mean age of 26.6 ± 4.9 years, a body mass index of 23.7 ± 3.5 kg m(-2) and an Epworth Sleepiness Scale score of 7.3 ± 2.7. There was no change in weight or the Epworth Sleepiness Scale in the four study periods. The rapid eye movement sleep percentage was significantly lower during fasting. There was no difference in sleep latency, non-rapid eye movement sleep percentage, arousal index and sleep efficiency. The multiple sleep latency test analysis revealed no difference in the sleep latency between the 'non-fasting baseline', 'baseline fasting', 'Ramadan' and 'Recovery' time points. Under conditions of a fixed sleep-wake schedule and a fixed caloric intake, Islamic intermittent fasting results in decreased rapid eye movement sleep with no impact on other sleep stages, the arousal index or daytime sleepiness. © 2013 European Sleep Research Society.

Obstructive Sleep-Disordered Breathing Is More Common than Central in Mild Familial Dysautonomia

PubMed Central

Hilz, Max J.; Moeller, Sebastian; Buechner, Susanne; Czarkowska, Hanna; Ayappa, Indu; Axelrod, Felicia B.; Rapoport, David M.

2016-01-01

Study Objectives: In familial dysautonomia (FD) patients, sleep-disordered breathing (SDB) might contribute to their high risk of sleep-related sudden death. Prevalence of central versus obstructive sleep apneas is controversial but may be therapeutically relevant. We, therefore, assessed sleep structure and SDB in FD-patients with no history of SDB. Methods: 11 mildly affected FD-patients (28 ± 11 years) without clinically overt SDB and 13 controls (28 ± 10 years) underwent polysomnographic recording during one night. We assessed sleep stages, obstructive and central apneas (≥ 90% air flow reduction) and hypopneas (> 30% decrease in airflow with ≥ 4% oxygen-desaturation), and determined obstructive (oAI) and central (cAI) apnea indices and the hypopnea index (HI) as count of respective apneas/hypopneas divided by sleep time. We obtained the apnea-hypopnea index (AHI4%) from the total of apneas and hypopneas divided by sleep time. We determined differences between FD-patients and controls using the U-test and within-group differences between oAIs, cAIs, and HIs using the Friedman test and Wilcoxon test. Results: Sleep structure was similar in FD-patients and controls. AHI4% and HI were significantly higher in patients than controls. In patients, HIs were higher than oAIs and oAIs were higher than cAIs. In controls, there was no difference between HIs, oAIs, and cAIs. Only patients had apneas and hypopneas during slow wave sleep. Conclusions: In our FD-patients, obstructive apneas were more common than central apneas. These findings may be related to FD-specific pathophysiology. The potential ramifications of SDB in FD-patients suggest the utility of polysomnography to unveil SDB and initiate treatment. Commentary: A commentary on this article appears in this issue on page 1583. Citation: Hilz MJ, Moeller S, Buechner S, Czarkowska H, Ayappa I, Axelrod FB, Rapoport DM. Obstructive sleep-disordered breathing is more common than central in mild familial dysautonomia. J Clin Sleep Med 2016;12(12):1607–1614. PMID:27655467

A dynamic deep sleep stage in Drosophila.

PubMed

van Alphen, Bart; Yap, Melvyn H W; Kirszenblat, Leonie; Kottler, Benjamin; van Swinderen, Bruno

2013-04-17

How might one determine whether simple animals such as flies sleep in stages? Sleep in mammals is a dynamic process involving different stages of sleep intensity, and these are typically associated with measurable changes in brain activity (Blake and Gerard, 1937; Rechtschaffen and Kales, 1968; Webb and Agnew, 1971). Evidence for different sleep stages in invertebrates remains elusive, even though it has been well established that many invertebrate species require sleep (Campbell and Tobler, 1984; Hendricks et al., 2000; Shaw et al., 2000; Sauer et al., 2003). Here we used electrophysiology and arousal-testing paradigms to show that the fruit fly, Drosophila melanogaster, transitions between deeper and lighter sleep within extended bouts of inactivity, with deeper sleep intensities after ∼15 and ∼30 min of inactivity. As in mammals, the timing and intensity of these dynamic sleep processes in flies is homeostatically regulated and modulated by behavioral experience. Two molecules linked to synaptic plasticity regulate the intensity of the first deep sleep stage. Optogenetic upregulation of cyclic adenosine monophosphate during the day increases sleep intensity at night, whereas loss of function of a molecule involved in synaptic pruning, the fragile-X mental retardation protein, increases sleep intensity during the day. Our results show that sleep is not homogenous in insects, and suggest that waking behavior and the associated synaptic plasticity mechanisms determine the timing and intensity of deep sleep stages in Drosophila.

Automatic sleep staging using empirical mode decomposition, discrete wavelet transform, time-domain, and nonlinear dynamics features of heart rate variability signals.

PubMed

Ebrahimi, Farideh; Setarehdan, Seyed-Kamaledin; Ayala-Moyeda, Jose; Nazeran, Homer

2013-10-01

The conventional method for sleep staging is to analyze polysomnograms (PSGs) recorded in a sleep lab. The electroencephalogram (EEG) is one of the most important signals in PSGs but recording and analysis of this signal presents a number of technical challenges, especially at home. Instead, electrocardiograms (ECGs) are much easier to record and may offer an attractive alternative for home sleep monitoring. The heart rate variability (HRV) signal proves suitable for automatic sleep staging. Thirty PSGs from the Sleep Heart Health Study (SHHS) database were used. Three feature sets were extracted from 5- and 0.5-min HRV segments: time-domain features, nonlinear-dynamics features and time-frequency features. The latter was achieved by using empirical mode decomposition (EMD) and discrete wavelet transform (DWT) methods. Normalized energies in important frequency bands of HRV signals were computed using time-frequency methods. ANOVA and t-test were used for statistical evaluations. Automatic sleep staging was based on HRV signal features. The ANOVA followed by a post hoc Bonferroni was used for individual feature assessment. Most features were beneficial for sleep staging. A t-test was used to compare the means of extracted features in 5- and 0.5-min HRV segments. The results showed that the extracted features means were statistically similar for a small number of features. A separability measure showed that time-frequency features, especially EMD features, had larger separation than others. There was not a sizable difference in separability of linear features between 5- and 0.5-min HRV segments but separability of nonlinear features, especially EMD features, decreased in 0.5-min HRV segments. HRV signal features were classified by linear discriminant (LD) and quadratic discriminant (QD) methods. Classification results based on features from 5-min segments surpassed those obtained from 0.5-min segments. The best result was obtained from features using 5-min HRV segments classified by the LD classifier. A combination of linear/nonlinear features from HRV signals is effective in automatic sleep staging. Moreover, time-frequency features are more informative than others. In addition, a separability measure and classification results showed that HRV signal features, especially nonlinear features, extracted from 5-min segments are more discriminative than those from 0.5-min segments in automatic sleep staging. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

The influence of chronotype and intelligence on academic achievement in primary school is mediated by conscientiousness, midpoint of sleep and motivation.

PubMed

Arbabi, Talat; Vollmer, Christian; Dörfler, Tobias; Randler, Christoph

2015-04-01

Individuals differ in their timing of sleep (bed times, rise times) and in their preference for morning or evening hours. Previous work focused on the relationship between academic achievement and these variables in secondary school students. The main aim of the study is to investigate the relationship between chronotype and academic achievement in 10-year-old children (n = 1125) attending 4th grade of primary school. They filled a cognitive test (Culture Fair Intelligence Test, CFT 20-R) and questions about rise times and bed times, academic achievement, conscientiousness and motivation. We used the "scales for the assessment of learning and performance motivation" (SELLMO; Skalen zur Erfassung der Lern- und Leistungsmotivation for motivation), the short version of the Five-Factor Personality Inventory Children (FFPI-C) to measure conscientiousness, and the Composite Scale of Morningness (CSM) to assess morningness-eveningness. Mean CSM score was 37.84 ± 6.66, midpoint of sleep was 1:36 ± 00:25 and average sleep duration (time in bed) was 10:15 ± 0:48. Morningness orientation was positively related to intelligence, conscientiousness and learning objectives. Eveningness orientation was related to avoidance performance objectives and work avoidance. Early midpoint of sleep, conscientiousness and intelligence were associated with better grades. The multivariate model showed that intelligence was the strongest predictor of good grades. Conscientiousness, motivation, younger age and an earlier midpoint of sleep were positively related to good grades. This is the first study in primary school pupils, and it shows that the relationship between evening orientation and academic achievement is already prevalent at this age even when controlling for important predictors of achievement.

Oculomotor impairment during chronic partial sleep deprivation.

PubMed

Russo, M; Thomas, M; Thorne, D; Sing, H; Redmond, D; Rowland, L; Johnson, D; Hall, S; Krichmar, J; Balkin, T

2003-04-01

The effects of chronic partial sleep (sleep deprivation) and extended sleep (sleep augmentation) followed by recovery sleep on oculomotor function were evaluated in normal subjects to explore the usefulness of oculomotor assessment for alertness monitoring in fitness-for-duty testing. Sixty-six commercial drivers (24-62 years, 50m/16f) participated in a 15 day study composed of 3 training days with 8h time in bed per night, 7 experimental days with subjects randomly assigned to either 3, 5, 7, or 9h time in bed, and 3 recovery nights with 8h time in bed. Data from 57 subjects were used. Saccadic velocity (SV), initial pupil diameter (IPD), latency to pupil constriction (CL), and amplitude of pupil constriction (CA) were assessed and correlated with the sleep latency test (SLT), the Stanford sleepiness scale (SSS), and simulated driving performance. Regression analyses showed that SV slowed significantly in the 3 and 5h groups, IPD decreased significantly in the 9h group, and CL increased significantly in the 3h group. SLT and SSS significantly correlated with SV, IPD, CL, and driving accidents for the 3h group, and with CL for the 5h group. Analyses also showed a significant negative correlation between decreasing SV and increasing driving accidents in the 3h group and a significant negative correlation between IPD and driving accidents for the 7h group. The results demonstrate a sensitivity primarily of SV to sleepiness, and a correlation of SV and IPD to impaired simulated driving performance, providing evidence for the potential utility of oculomotor indicators in the detection of excessive sleepiness and deterioration of complex motor performance with chronic partial sleep restriction. This paper shows a relationship between sleep deprivation and oculomotor measures, and suggests a potential utility for oculometrics in assessing operational performance readiness under sleep restricted conditions.

The impact of diurnal sleep on the consolidation of a complex gross motor adaptation task

PubMed Central

Hoedlmoser, Kerstin; Birklbauer, Juergen; Schabus, Manuel; Eibenberger, Patrick; Rigler, Sandra; Mueller, Erich

2015-01-01

Diurnal sleep effects on consolidation of a complex, ecological valid gross motor adaptation task were examined using a bicycle with an inverse steering device. We tested 24 male subjects aged between 20 and 29 years using a between-subjects design. Participants were trained to adapt to the inverse steering bicycle during 45 min. Performance was tested before (TEST1) and after (TEST2) training, as well as after a 2 h retention interval (TEST3). During retention, participants either slept or remained awake. To assess gross motor performance, subjects had to ride the inverse steering bicycle 3 × 30 m straight-line and 3 × 30 m through a slalom. Beyond riding time, we sophisticatedly measured performance accuracy (standard deviation of steering angle) in both conditions using a rotatory potentiometer. A significant decrease of accuracy during straight-line riding after nap and wakefulness was shown. Accuracy during slalom riding remained stable after wakefulness but was reduced after sleep. We found that the duration of rapid eye movement sleep as well as sleep spindle activity are negatively related with gross motor performance changes over sleep. Together these findings suggest that the consolidation of adaptation to a new steering device does not benefit from a 2 h midday nap. We speculate that in case of strongly overlearned motor patterns such as normal cycling, diurnal sleep spindles and rapid eye movement sleep might even help to protect everyday needed skills, and to rapidly forget newly acquired, interfering and irrelevant material. PMID:25256866

Relationship between napping during night shift work and household obligations of female nursing personnel.

PubMed

Silva-Costa, Aline; Fischer, Frida Marina; Griep, Rosane Harter; Rotenberg, Lúcia

2013-01-01

Night shift employment involves displacing sleep to the daytime. For female workers, the opportunity for daytime sleep is influenced by routine housework demands, which aggravates sleep deprivation. Allowing naps to be taken during the night shift of work is a frequent practice at some hospitals and can help reduce the effects of sleep deprivation. We hypothesize that an association between domestic work and the length of naps during night work exists for nursing professionals. To test this hypothesis, two cross-sectional studies were conducted in two different hospitals. In Study 1, female workers answered questionnaires regarding sleeping habits, professional work, and housework demands. In Study 2, data regarding napping during shifts was obtained by actigraphy, a noninvasive method of monitoring the human sleep-wake cycle. The demand for the performance of housework was measured by (i) domestic work hours (total time spent performing domestic work per week), and (ii) domestic workload, which considers the degree of sharing domestic tasks and the number of people living at home. The populations from the two studies were subdivided into groups, based on the duration of napping at work. Data on naps were analyzed according to domestic demands, using the Mann-Whitney and Chi-squared tests. Among the two study populations (Studies 1 and 2), those in Study 2 were older, had shorter professional weekly work hours, worked more night shifts, and dedicated more time to housework. significant associations were only found in Study 2, where greater time napping at work was associated with both greater time spent doing housework and greater domestic workload. The known benefits of napping during night shifts seem to be especially relevant for female workers who are more sleep-deprived from working more night shifts and who have higher demands for housework.

Circadian rhythms and sleep have additive effects on respiration in the rat

PubMed Central

Stephenson, Richard; Liao, Kiong Sen; Hamrahi, Hedieh; Horner, Richard L

2001-01-01

We tested two hypotheses: that respiration and metabolism are subject to circadian modulation in wakefulness, non-rapid-eye-movement (NREM) sleep and rapid-eye-movement (REM) sleep; and that the effects of sleep on breathing vary as a function of time of day.Electroencephalogram (EEG), neck electromyogram (EMG) and abdominal body temperature (Tb) were measured by telemetry in six male Sprague-Dawley rats. The EEG and EMG were used to identify sleep-wake states. Ventilation (V̇I) and metabolic rate (V̇CO2) were measured by plethysmography. Recordings were made over 24 h (12:12 h light:dark) when rats were in established states of wakefulness, NREM sleep and REM sleep.Statistically significant circadian rhythms were observed in V̇I and V̇CO2 in each of the wakefulness, NREM sleep and REM sleep states. Amplitudes and phases of the circadian rhythms were similar across sleep-wake states.The circadian rhythm in V̇I was mediated by a circadian rhythm in respiratory frequency (fR). Tidal volume (VT) was unaffected by time of day in all three sleep-wake states.The 24 h mean V̇I was significantly greater during wakefulness (363.5 ± 18.5 ml min−1) than during NREM sleep (284.8 ± 11.1 ml min−1) and REM sleep (276.1 ± 13.9 ml min−1). V̇CO2 and VT each significantly decreased from wakefulness to NREM sleep to REM sleep. fR was significantly lower in NREM sleep than in wakefulness and REM sleep.These data confirm that ventilation and metabolism exhibit circadian rhythms during wakefulness, and NREM and REM sleep, and refute the hypothesis that state-related effects on breathing vary as a function of time of day. We conclude that the effects of circadian rhythms and sleep-wake state on respiration and metabolic rate are additive in the rat. PMID:11579171

Sleep Environments and Sleep Durations in a Sample of Low-Income Preschool Children

PubMed Central

Wilson, Katherine E.; Miller, Alison L.; Lumeng, Julie C.; Chervin, Ronald D.

2014-01-01

Study Objectives: Sleep duration is commonly studied in children, but less is known about the potential impact of adverse sleep environments, particularly at preschool ages. We examined the frequency of suboptimal sleep environments and tested for associations with sleep duration or nocturnal sleep time among low-income preschool children. Methods: Parents of Head Start preschoolers in Michigan (Detroit and greater Lansing) completed questionnaires on children's sleep schedules and sleep environments. Respondents indicated how often their children slept in a place “too bright,” “too loud,” “too cold,” or “too hot” on a scale of 1 = never to 5 = always. A suboptimal sleep environment (SSE) was defined when one or more of these conditions were reported for ≥ 1-2 nights/week. Weeknight sleep duration or reported time that the child went to sleep was regressed on SSE as an explanatory variable, with adjustment for age, race/ethnicity, gender, maternal education, and average daily nap duration. Results: Among 133 preschool children, mean age was 4.1 ± 0.5 (SD), 48% were male, 39% were white, and 52% were black; 34% of parents had ≤ a high school degree. Parents reported that 26 (20%) of the children slept in a SSE ≥ 1-2 nights per week. In regression models, SSE was associated with 27 minutes shorter sleep duration (β = -0.45, SE = 0.22, p = 0.044) and 22 minutes later time child “fell asleep” (β = 0.37, SE = 0.19, p = 0.048) on weeknights. Conclusions: Among these Head Start preschool children, environmental challenges to adequate sleep are not uncommon, and they may have consequences. Clinician or preschool assessment of sleep environments may open opportunities to improve sleep at early ages. Citation: Wilson KE; Miller AL; Lumeng JC; Chervin RD. Sleep environments and sleep durations in a sample of low-income preschool children. J Clin Sleep Med 2014;10(3):299-305. PMID:24634628

The efficacy of melatonin for sleep problems in children with autism, fragile X syndrome, or autism and fragile X syndrome.

PubMed

Wirojanan, Juthamas; Jacquemont, Sebastien; Diaz, Rafael; Bacalman, Susan; Anders, Thomas F; Hagerman, Randi J; Goodlin-Jones, Beth L

2009-04-15

To determine the efficacy of melatonin on sleep problems in children with autistic spectrum disorder (ASD) and fragile X syndrome (FXS). A 4-week, randomized, double blind, placebo-controlled, crossover design was conducted following a 1-week baseline period. Either melatonin, 3 mg, or placebo was given to participants for 2 weeks and then alternated for another 2 weeks. Sleep variables, including sleep duration, sleep-onset time, sleep-onset latency time, and the number of night awakenings, were recorded using an Actiwatch and from sleep diaries completed by parents. All participants had been thoroughly assessed for ASD and also had DNA testing for the diagnosis of FXS. Data were successfully obtained from the 12 of 18 subjects who completed the study (11 males, age range 2 to 15.25 years, mean 5.47, SD 3.6). Five participants met diagnostic criteria for ASD, 3 for FXS alone, 3 for FXS and ASD, and 1 for fragile X premutation. Eight out of 12 had melatonin first. The conclusions from a nonparametric repeated-measures technique indicate that mean night sleep duration was longer on melatonin than placebo by 21 minutes (p = .02), mean sleep-onset latency was shorter by 28 minutes (p = .0001), and mean sleep-onset time was earlier by 42 minutes (p = .02). The results of this study support the efficacy and tolerability of melatonin treatment for sleep problems in children with ASD and FXS.

The Orexin Antagonist SB-649868 Promotes and Maintains Sleep in Men with Primary Insomnia

PubMed Central

Bettica, Paolo; Squassante, Lisa; Zamuner, Stefano; Nucci, Gianluca; Danker-Hopfe, Heidi; Ratti, Emiliangelo

2012-01-01

Study Objectives: To assess the acute effects of SB-649868 in male subjects with Primary Insomnia with regard to (1) objective and subjective sleep parameters, (2) safety and tolerability, (3) next-day residual effects. Design: Multicenter, randomized, double-blind, placebo-controlled crossover study using a complete set of Williams orthogonal Latin Squares Setting: 9 sleep centers in Germany Patients: 52 male subjects with a diagnosis of primary insomnia (difficulty in sleep initiation and maintenance) confirmed by polysomnography Interventions: SB-649868 (10, 30, 60 mg) and placebo administered after dinner 90 minutes before bedtime Measurements and Results: Sleep effects assessed by polysomnography during 2 consecutive nights and by sleep questionnaires completed by subjects after each night at the sleep laboratory. Safety and tolerability were assessed by adverse events collection, electrocardiogram (ECG), vital signs, laboratory tests. Next-day residual effects were assessed by Digit Symbol Substitution Test, and modified Verbal Learning Memory Test administered at “lights on” after night 2. SB-649868 significantly reduced latency to persistent sleep, wake after sleep onset (WASO), and increased total sleep time (TST) compared to placebo. A dose-dependent effect was observed. A dose-dependent increase in absolute and percent REM sleep and reduction in REM sleep latency was observed mainly at the 60-mg dose. SB-649868 was well tolerated with inconsistent next day residual effects. SB-649868 sleep effects were correlated with SB-649868 circulating levels. Conclusion: The data demonstrate the sleep-promoting properties of the orexin antagonist SB-649868 in male patients with insomnia. Clinical Trials Information: This study was registered on ClinicalTrials.gov with the following identifier: NCT00426816. URL: http://www.clinicaltrial.gov/ct2/show/NCT00426816?term=649868&rank=5. Citation: Bettica P; Squassante L; Zamuner S; Nucci G; Danker-Hopfe H; Ratti E. The orexin antagonist SB-649868 promotes and maintains sleep in men with primary insomnia. SLEEP 2012;35(8):1097-1104. PMID:22851805

The ERP old-new effect: A useful indicator in studying the effects of sleep on memory retrieval processes.

PubMed

Mograss, Melodee; Godbout, Roger; Guillem, F

2006-11-01

To verify that the classic "Old/New" memory effect can be detected after a long delay, and to investigate the differential influence of declarative memory processes after normal sleep and daytime wake. The protocol is a variation of a more traditional study-recognition test used in event-related potential (ERP) studies in which sleep or wake is inserted between the learning and recognition session in order to verify the existence of the Old/New effect (ie, positive shift that occurs when stimuli are repeated). ERPs were recorded during the recognition-test session. The protocol was based on early work that compared the effect of sleep on memory without recording sleep. Data collection occurred in the outpatient sleep laboratory. Results from 13 subjects (6 men) aged between 21 and 39 years. The subjects performed the recognition memory test after sleep and daytime wake periods. More-accurate performance for the old (studied) stimuli occurred after the sleep session. Analysis of variance on correctly answered reaction times revealed a significant effect of condition (old/new) with no difference across session. A repeated-measure analysis revealed differences in "Old/New" effect, whereby the amplitude difference between the old and new items was larger after sleep than after wake. This effect of sleep was found in early frontal and later posterior ERP components, processes that represent strategic, contextual processing and facilitation of episodic memory. Memory representation was not different across sessions. These findings suggest that sleep and wake facilitate 2 components of memory unequally, ie, episodic recognition and memory representation functioning.

Post-Learning Sleep Transiently Boosts Context Specific Operant Extinction Memory.

PubMed

Borquez, Margarita; Contreras, María P; Vivaldi, Ennio; Born, Jan; Inostroza, Marion

2017-01-01

Operant extinction is learning to supress a previously rewarded behavior. It is known to be strongly associated with the specific context in which it was acquired, which limits the therapeutic use of operant extinction in behavioral treatments, e.g., of addiction. We examined whether sleep influences contextual memory of operant extinction over time, using two different recall tests (Recent and Remote). Rats were trained in an operant conditioning task (lever press) in context A, then underwent extinction training in context B, followed by a 3-h retention period that contained either spontaneous morning sleep, morning sleep deprivation, or spontaneous evening wakefulness. A recall test was performed either immediately after the 3-h experimental retention period (Recent recall) or after 48 h (Remote), in the extinction context B and in a novel context C. The two main findings were: (i) at the Recent recall test, sleep in comparison with sleep deprivation and spontaneous wakefulness enhanced extinction memory but, only in the extinction context B; (ii) at the Remote recall, extinction performance after sleep was enhanced in both contexts B and C to an extent comparable to levels at Recent recall in context B. Interestingly, extinction performance at Remote recall was also improved in the sleep deprivation groups in both contexts, with no difference to performance in the sleep group. Our results suggest that 3 h of post-learning sleep transiently facilitate the context specificity of operant extinction at a Recent recall. However, the improvement and contextual generalization of operant extinction memory observed in the long-term, i.e., after 48 h, does not require immediate post-learning sleep.

The effect of one night's sleep deprivation on adolescent neurobehavioral performance.

PubMed

Louca, Mia; Short, Michelle A

2014-11-01

To investigate the effects of one night's sleep deprivation on neurobehavioral functioning in adolescents. Participants completed a neurobehavioral test battery measuring sustained attention, reaction speed, cognitive processing speed, sleepiness, and fatigue every 2 h during wakefulness. Baseline performance (defined as those test bouts between 09:00 and 19:00 on days 2 and 3, following two 10-h sleep opportunities) were compared to performance at the same clock time the day following total sleep deprivation. The sleep laboratory at the Centre for Sleep Research. Twelve healthy adolescents (6 male), aged 14-18 years (mean = 16.17, standard deviation = 0.83). Sustained attention, reaction speed, cognitive processing speed, and subjective sleepiness were all significantly worse following one night without sleep than following 10-h sleep opportunities (all main effects of day, P < 0.05). Sleep deprivation led to increased variability on objective performance measures. There were between-subjects differences in response to sleep loss that were task-specific, suggesting that adolescents may not only vary in terms of the degree to which they are affected by sleep loss but also the domains in which they are affected. These findings suggest that one night of total sleep deprivation has significant deleterious effects upon neurobehavioral performance and subjective sleepiness. These factors impair daytime functioning in adolescents, leaving them at greater risk of poor academic and social functioning and accidents and injuries.

Biological markers of melancholia and reclassification of depressive disorders.

PubMed

Greden, J F

1982-01-01

Pathophysiological markers of melancholia are being developed in four major areas: 1) neuroendocrine; 2) sleep; 3) psychomotor and 4) biochemical. Neuroendocrine markers include a failure of suppress plasma cortisol secretion in the dexamethasone suppression test (DST), diminished thyrotrophin (TSH) response to thyrotrophin releasing hormone (TRH stimulation test), and blunted growth hormone response to a variety of stimulating agents such as d-amphetamine, methylamphetamine, clonidine, L-dopa and insulin (growth hormone test). Of these, the DST is the best standardized. It is a highly specific laboratory marker with documented value in diagnosis, assessing prognosis and monitoring treatment progress. Sleep EEG abnormalities include reduced REM latency, increased REM density, reduction in delta sleep and impaired sleep efficiency. Sleep EEGs are pragmatically difficult, but results are quite specific. Elongated speech pause time (SPT) during "automatic speech" is a promising marker of psychomotor regulation. This simple, non-invasive measure may have special value in reducing clinical subjectivity and in monitoring treatment progress. Biochemical markers include: 1) platelet monoamine oxidase (MAO) activity; 2) in vitro lithium RBC transport and 3) urinary MHPG levels. Standardizations of biochemical tests are still lacking. Most biological tests for melancholia operate by indirectly "marking" CNS limbic system dysfunction. For wide acceptance, a test must be safe, moderately sensitive, highly specific, practical, relatively inexpensive and not significantly altered by common anti-depressant treatments. The DST best meets these criteria at this time. Proper utilization of test results requires knowledge of baseline prevalence rates and of the concepts of sensitivity (true-positive rate), specificity (true negative rate) and positive and negative predictive values (diagnostic confidence). No single marker will meet all clinical needs. Combinations or serial use of tests will hopefully enhance their already considerable usefulness.

Does Sleep Improve Memory Organization?

PubMed Central

Takeuchi, Masashi; Furuta, Hisakazu; Sumiyoshi, Tomiki; Suzuki, Michio; Ochiai, Yoko; Hosokawa, Munehito; Matsui, Mie; Kurachi, Masayoshi

2014-01-01

Sleep can integrate information into existing memory networks, look for common patterns and distil overarching rules, or simply stabilize and strengthen the memory exactly as it was learned. Recent research has shown that sleep facilitates abstraction of gist information as well as integration across multiple memories, insight into hidden solutions, and even the ability to make creative connections between distantly related ideas and concepts. To investigate the effect of sleep on memory organization, 35 normal volunteers were randomly assigned either to the sleep (n = 17) or wake group (n = 18). The sleep subjects performed the Japanese Verbal Learning Test (JVLT), a measure of learning and memory, three times in the evening, and slept. On the following morning (9 h later), they were asked to recall the words on the list. The wake subjects took the same test in the morning, and were asked to recall the words in the same time interval as in the sleep group. The semantic clustering ratio (SCR), divided by the total number of words recalled, was used as an index of memory organization. Our main interest was whether the sleep subjects elicit a greater increase in this measure from the third to the fourth assessments. Time × Group interaction effect on SCR was not significant between the sleep group and wake group as a whole. Meanwhile, the change in the SCR between the third and fourth trials was negatively correlated with duration of nocturnal waking in the sleep group, but not other sleep indices. Based on this observation, further analysis was conducted for subjects in the sleep group who awoke nocturnally for <60 min for comparison with the wake group. A significant Time × Group interaction was noted; these “good-sleepers” showed a significantly greater improvement in the memory index compared with the wake subjects. These results provide the first suggestion that sleep may enhance memory organization, which requires further study. PMID:24782726

Normobaric hypoxia overnight impairs cognitive reaction time.

PubMed

Pramsohler, Stephan; Wimmer, Stefan; Kopp, Martin; Gatterer, Hannes; Faulhaber, Martin; Burtscher, Martin; Netzer, Nikolaus Cristoph

2017-05-15

Impaired reaction time in patients suffering from hypoxia during sleep, caused by sleep breathing disorders, is a well-described phenomenon. High altitude sleep is known to induce periodic breathing with central apneas and oxygen desaturations, even in perfectly healthy subjects. However, deficits in reaction time in mountaineers or workers after just some nights of hypoxia exposure are not sufficiently explored. Therefore, we aimed to investigate the impact of sleep in a normobaric hypoxic environment on reaction time divided by its cognitive and motoric components. Eleven healthy non acclimatized students (5f, 6m, 21 ± 2.1 years) slept one night at a simulated altitude of 3500 m in a normobaric hypoxic room, followed by a night with polysomnography at simulated 5500 m. Preexisting sleep disorders were excluded via BERLIN questionnaire. All subjects performed a choice reaction test (SCHUHFRIED RT, S3) at 450 m and directly after the nights at simulated 3500 and 5500 m. We found a significant increase of cognitive reaction time with higher altitude (p = 0.026). No changes were detected in movement time (p = n.s.). Reaction time, the combined parameter of cognitive- and motoric reaction time, didn't change either (p = n.s.). Lower SpO 2 surprisingly correlated significantly with shorter cognitive reaction time (r = 0.78, p = 0.004). Sleep stage distribution and arousals at 5500 m didn't correlate with reaction time, cognitive reaction time or movement time. Sleep in hypoxia does not seem to affect reaction time to simple tasks. The component of cognitive reaction time is increasingly delayed whereas motoric reaction time seems not to be affected. Low SpO 2 and arousals are not related to increased cognitive reaction time therefore the causality remains unclear. The fact of increased cognitive reaction time after sleep in hypoxia, considering high altitude workers and mountaineering operations with overnight stays, should be further investigated.

Effects of noise on sleep inertia as a function of circadian placement of a one-hour nap.

PubMed

Tassi, P; Nicolas, A; Dewasmes, G; Eschenlauer, R; Ehrhart, J; Salame, P; Muzet, A; Libert, J P

1992-08-01

The purpose of the present study was to analyse the arousing effects of noise on sleep inertia as a function of circadian placement of a one-hour nap. In a first experiment, we measured the effects of sleep inertia in a neutral acoustic environment after a one-hour nap placed either at 0100 or 0400 on response time during a spatial memory test. In a second experiment were analysed the effects of an intense continuous noise on sleep inertia. The results showed that noise produced a total abolition of sleep inertia after an early nap (0000 to 0100). This may be due to the arousing effect of noise; however, results are less clear after a late nap 0300 to 0400 as noise seems to be ineffective. This result is discussed in terms of either a function of time-of-day effect or of prior sleep intensity. Moreover, our data suggest a possible interaction of noise with partial sleep deprivation leading to a slight deleterious effect those subjects who did not sleep at all.

Sleep Quantity and Quality during Acute Concussion: A Pilot Study.

PubMed

Raikes, Adam C; Schaefer, Sydney Y

2016-12-01

A number of subjective and objective studies provide compelling evidence of chronic post-concussion changes in sleep, yet very little is known about the acute effects of concussion on sleep quality and quantity. Therefore, the purpose of this prospective pilot study was to use actigraphy to examine the changes in sleep quality and quantity acutely following concussion at home rather than in a hospital or sleep laboratory. Seventeen young adults (7 with acute concussion, 10 controls) were recruited for this study. All participants completed two 5-day testing sessions separated by 30 days from intake (controls) or day of injury (concussion). Participants wore actigraphs and kept a sleep journal. Sleep parameter outcomes included nighttime total sleep time (nTST), 24-h total sleep time (TST), wake after sleep onset (WASO), and sleep efficiency (SE). The coefficient of variation (CV) for each sleep parameter was computed for each session. nTST and TST CV was significantly greater in the concussion group. There is the additional indication that individuals with a concussion may require and obtain more sleep shortly after injury and subsequently have a shorter duration of sleep at 1 mo post-injury. This pattern was not seen in the measures of sleep quality (WASO, SE). Individuals with a concussion demonstrated increased nighttime sleep duration variability. This increase persisted at 1 mo post-injury and may be associated with previously documented self-reports of poor sleep quality lasting months and years after a concussion. Additionally, this increase may predispose individuals to numerous negative health outcomes if left untreated. © 2016 Associated Professional Sleep Societies, LLC.

Hemodynamic and psychological responses to laboratory stressors in women: Assessing the roles of menstrual cycle phase, premenstrual symptomatology, and sleep characteristics

PubMed Central

Lustyk, M. Kathleen B.; Douglas, Haley A.C.; Shilling, Elizabeth A.; Woods, Nancy F.

2016-01-01

This study assessed whether premenstrual symptomatology and/or sleep characteristics explain increased luteal phase psychophysiological reactivity to laboratory stressors. We hypothesized that: (1) premenstrual symptoms and sleep characteristics would explain greater luteal versus follicular phase psychophysiological reactivity, (2) symptoms and sleep characteristics would differentially predict psychophysiological reactivity within each cycle phase, and (3) symptoms and sleep characteristics would interact to affect luteal but not follicular reactivity. Freely cycling women (N=87) completed two laboratory sessions, one follicular (cycle days 5–9) and one luteal (days 7–10 post-ovulation). We employed two stressors: one physical (cold pressor task) and the other cognitive in nature (Paced Auditory Serial Addition Task). During testing, electrocardiography monitored heart rate (HR) while a timed and auto-inflatable sphygmomanometer assessed blood pressure (BP). Participants also completed a one-time self-report measure of sleep characteristics and premenstrual symptomatology as well as a measure of state anxiety pre-post stressor. Results revealed greater luteal HR and systolic BP reactivity compared to follicular reactivity (p<0.001 for both analyses), however neither premenstrual symptoms nor sleep characteristics explained this luteal increase. Within cycle analyses revealed that symptoms and sleep characteristics interacted to affect luteal phase state anxiety reactivity (R2=.32, p=.002) with negative affect being associated with more reactivity when sleep hours were low (β=.333, p=.04). Overall, significant relationships existed during the luteal phase only. Findings are discussed in terms of clinical utility and methodological challenges related to performing laboratory stress testing in women. PMID:23092740

Changes in Subjective Sleep Quality Before a Competition and Their Relation to Competitive Anxiety.

PubMed

Ehrlenspiel, Felix; Erlacher, Daniel; Ziegler, Matthias

2016-12-09

The aim of this study was to examine the effects of competitions on subjective sleep quality. Previous studies have been inconclusive and lack differentiated and standardized measurements of subjective sleep quality. Furthermore the temporal relation between precompetitive anxiety and sleep quality was investigated. Anxiety and nervousness associated with competitions are considered to cause sleep impairments. A convenience sample of N = 79 elite male athletes from various sports participated. In a time-to-event paradigm, sleep quality and competitive anxiety were assessed via standardized self-report measurements 4 days before a competition and on the day of the competition. Univariate analyses were used to examine differences between time points. To examine cross-lagged effects between anxiety and sleep quality a latent change score model (LCSM) was specified that tested an effect of anxiety on changes in sleep quality. Evaluations of nocturnal sleep deteriorated significantly from 4 days before competition to the day of competition, but there were no differences regarding perceptions of the restorative value of sleep. LCSM revealed that athletes who reported more intense worry symptoms 4 days before competition also reported greater deterioration in evaluations of nocturnal sleep. The findings support earlier reports of impaired subjective sleep quality before competitions. Precompetitive sleep impairments appear also to be preceded by cognitive anxiety. Whereas interventions should thus address worry-cognitions associated with competition and sleep, research should address the practical importance of these perceptions of sleep impairments.

Role of REM Sleep, Melanin Concentrating Hormone and Orexin/Hypocretin Systems in the Sleep Deprivation Pre-Ischemia

PubMed Central

Pace, Marta; Adamantidis, Antoine; Facchin, Laura; Bassetti, Claudio

2017-01-01

Study Objectives Sleep reduction after stroke is linked to poor recovery in patients. Conversely, a neuroprotective effect is observed in animals subjected to acute sleep deprivation (SD) before ischemia. This neuroprotection is associated with an increase of the sleep, melanin concentrating hormone (MCH) and orexin/hypocretin (OX) systems. This study aims to 1) assess the relationship between sleep and recovery; 2) test the association between MCH and OX systems with the pathological mechanisms of stroke. Methods Sprague-Dawley rats were assigned to four experimental groups: (i) SD_IS: SD performed before ischemia; (ii) IS: ischemia; (iii) SD_Sham: SD performed before sham surgery; (iv) Sham: sham surgery. EEG and EMG were recorded. The time-course of the MCH and OX gene expression was measured at 4, 12, 24 hours and 3, 4, 7 days following ischemic surgery by qRT-PCR. Results A reduction of infarct volume was observed in the SD_IS group, which correlated with an increase of REM sleep observed during the acute phase of stroke. Conversely, the IS group showed a reduction of REM sleep. Furthermore, ischemia induces an increase of MCH and OX systems during the acute phase of stroke, although, both systems were still increased for a long period of time only in the SD_IS group. Conclusions Our data indicates that REM sleep may be involved in the neuroprotective effect of SD pre-ischemia, and that both MCH and OX systems were increased during the acute phase of stroke. Future studies should assess the role of REM sleep as a prognostic marker, and test MCH and OXA agonists as new treatment options in the acute phase of stroke. PMID:28061506

Impact of 5-h phase advance on sleep architecture and physical performance in athletes.

PubMed

Petit, Elisabeth; Mougin, Fabienne; Bourdin, Hubert; Tio, Grégory; Haffen, Emmanuel

2014-11-01

Travel across time zones causes jet lag and is accompanied by deleterious effects on sleep and performance in athletes. These poor performances have been evaluated in field studies but not in laboratory conditions. The purpose of this study was to evaluate, in athletes, the impact of 5-h phase advance on the architecture of sleep and physical performances (Wingate test). In a sleep laboratory, 16 male athletes (age: 22.2 ± 1.7 years, height: 178.3 ± 5.6 cm, body mass: 73.6 ± 7.9 kg) spent 1 night in baseline condition and 2 nights, 1 week apart, in phase shift condition recorded by electroencephalography to calculate sleep architecture variables. For these last 2 nights, the clock was advanced by 5 h. Core body temperature rhythm was assessed continuously. The first night with phase advance decreased total sleep time, sleep efficiency, sleep onset latency, stage 2 of nonrapid eye movement (N2), and rapid eye movement (REM) sleep compared with baseline condition, whereas the second night decreased N2 and increased slow-wave sleep and REM, thus improving the quality of sleep. After phase advance, mean power improved, which resulted in higher lactatemia. Acrophase and bathyphase of temperature occurred earlier and amplitude decreased in phase advance but the period was not modified. These results suggest that a simulated phase shift contributed to the changes in sleep architecture, but did not significantly impair physical performances in relation with early phase adjustment of temperature to the new local time.

Protective Effect of Aerobic Physical Activity on Sleep Behavior in Breast Cancer Survivors.

PubMed

Roveda, Eliana; Vitale, Jacopo A; Bruno, Eleonora; Montaruli, Angela; Pasanisi, Patrizia; Villarini, Anna; Gargano, Giuliana; Galasso, Letizia; Berrino, Franco; Caumo, Andrea; Carandente, Franca

2017-03-01

Sleep disorders are associated with an increased risk of cancer, including breast cancer (BC). Physical activity (PA) can produce beneficial effects on sleep. We designed a randomized controlled trial to test the effect of 3 months of physical activity on sleep and circadian rhythm activity level evaluated by actigraphy. 40 BC women, aged 35-70 years, were randomized into an intervention (IG) and a control group (CG). IG performed a 3 month of aerobic exercise. At baseline and after 3 months, the following parameters were evaluated both for IG and CG: anthropometric and body composition measurements, energy expenditure and motion level; sleep parameters (Actual Sleep Time-AST, Actual Wake Time-AWT, Sleep Efficiency-SE, Sleep Latency-SL, Mean Activity Score-MAS, Movement and Fragmentation Index-MFI and Immobility Time-IT) and activity level circadian rhythm using the Actigraph Actiwatch. The CG showed a deterioration of sleep, whereas the IG showed a stable pattern. In the CG the SE, AST and IT decreased and the AWT, SL, MAS and MFI increased. In the IG, the SE, IT, AWT, SL, and MAS showed no changes and AST and MFI showed a less pronounced change in the IG than in the CG. The rhythmometric analysis revealed a significant circadian rhythm in two groups. After 3 months of PA, IG showed reduced fat mass %, while CG had improved weight and BMI. Physical activity may be beneficial against sleep disruption. Indeed, PA prevented sleep worsening in IG. PA can represent an integrative intervention therapy able to modify sleep behaviour.

Effects of stress upon psychophysiological responses and performance following sleep deprivation

NASA Technical Reports Server (NTRS)

Roessler, R.; Lester, J. W.

1972-01-01

The usefulness of psychological and physiological variables in predicting performance under stress of 48 hours of sleep deprivation was investigated. Performance tests, with subjects of different ego strength personalities, in concept acquisition, reading comprehension, word association, word memory, and anagrams were conducted, and physiological measurements of (1) the phasic and tonic electrodermal, (2) galvanic skin response, (3) thermal skin resistance, (4) heart rate, (5) respiration, and (6) plethysmographic finger pulse volumn were recorded. It was found that the changes in the pattern of performance were the result of testing subjects at times when they would normally be sleeping, and that sleep deprivation longer than 48 hours must be maintained to produce changes in simple or well learned tasks.

Countermeasures to Neurobehavioral Deficits from Cumulative Partial Sleep Deprivation During Space Flight

NASA Technical Reports Server (NTRS)

Dinges, David F.

1999-01-01

This project is concerned with identifying ways to prevent neurobehavioral and physical deterioration due to inadequate sleep in astronauts during long-duration manned space flight. The performance capability of astronauts during extended-duration space flight depends heavily on achieving recovery through adequate sleep. Even with appropriate circadian alignment, sleep loss can erode fundamental elements of human performance capability including vigilance, cognitive speed and accuracy, working memory, reaction time, and physiological alertness. Adequate sleep is essential during manned space flight not only to ensure high levels of safe and effective human performance, but also as a basic regulatory biology critical to healthy human functioning. There is now extensive objective evidence that astronaut sleep is frequently restricted in space flight to averages between 4 hr and 6.5 hr/day. Chronic sleep restriction during manned space flight can occur in response to endogenous disturbances of sleep (motion sickness, stress, circadian rhythms), environmental disruptions of sleep (noise, temperature, light), and curtailment of sleep due to the work demands and other activities that accompany extended space flight operations. The mechanism through which this risk emerges is the development of cumulative homeostatic pressure for sleep across consecutive days of inadequate sleep. Research has shown that the physiological sleepiness and performance deficits engendered by sleep debt can progressively worsen (i.e., accumulate) over consecutive days of sleep restriction, and that sleep limited to levels commonly experienced by astronauts (i.e., 4 - 6 hr per night) for as little as 1 week, can result in increased lapses of attention, degradation of response times, deficits in complex problem solving, reduced learning, mood disturbance, disruption of essential neuroendocrine, metabolic, and neuroimmune responses, and in some vulnerable persons, the emergence of uncontrolled sleep attacks. The prevention of cumulative performance deficits and neuroendocrine disruption from sleep restriction during extended duration space flight involves finding the most effective ways to obtain sleep in order to maintain the high-level cognitive and physical performance functions required for manned space flight. There is currently a critical deficiency in knowledge of the effects of how variations in sleep duration and timing relate to the most efficient return of performance per unit time invested in sleep during long-duration missions, and how the nature of sleep physiology (i.e., sleep stages, sleep electroencephalographic [EEG] power spectral analyses) change as a function of sleep restriction and performance degradation. The primary aim of this project is to meet these critical deficiencies through utilization of a response surface experimental paradigm, testing in a dose-response manner, varying combinations of sleep duration and timing, for the purpose of establishing how to most effectively limit the cumulative adverse effects on human performance and physiology of chronic sleep restriction in space operations.

Cognitive Workload and Sleep Restriction Interact to Influence Sleep Homeostatic Responses

PubMed Central

Goel, Namni; Abe, Takashi; Braun, Marcia E.; Dinges, David F.

2014-01-01

Study Objectives: Determine the effects of high versus moderate workload on sleep physiology and neurobehavioral measures, during sleep restriction (SR) and no sleep restriction (NSR) conditions. Design: Ten-night experiment involving cognitive workload and SR manipulations. Setting: Controlled laboratory environment. Participants: Sixty-three healthy adults (mean ± standard deviation: 33.2 ± 8.7 y; 29 females), age 22–50 y. Interventions: Following three baseline 8 h time in bed (TIB) nights, subjects were randomized to one of four conditions: high cognitive workload (HW) + SR; moderate cognitive workload (MW) + SR; HW + NSR; or MW + NSR. SR entailed 5 consecutive nights at 4 h TIB; NSR entailed 5 consecutive nights at 8 h TIB. Subjects received three workload test sessions/day consisting of 15-min preworkload assessments, followed by a 60-min (MW) or 120-min (HW) workload manipulation comprised of visually based cognitive tasks, and concluding with 15-min of postworkload assessments. Experimental nights were followed by two 8-h TIB recovery sleep nights. Polysomnography was collected on baseline night 3, experimental nights 1, 4, and 5, and recovery night 1 using three channels (central, frontal, occipital [C3, Fz, O2]). Measurements and Results: High workload, regardless of sleep duration, increased subjective fatigue and sleepiness (all P < 0.05). In contrast, sleep restriction produced cumulative increases in Psychomotor Vigilance Test (PVT) lapses, fatigue, and sleepiness and decreases in PVT response speed and Maintenance of Wakefulness Test (MWT) sleep onset latencies (all P < 0.05). High workload produced longer sleep onset latencies (P < 0.05, d = 0.63) and less wake after sleep onset (P < 0.05, d = 0.64) than moderate workload. Slow-wave energy—the putative marker of sleep homeostasis—was higher at O2 than C3 only in the HW + SR condition (P < 0.05). Conclusions: High cognitive workload delayed sleep onset, but it also promoted sleep homeostatic responses by increasing subjective fatigue and sleepiness, and producing a global sleep homeostatic response by reducing wake after sleep onset. When combined with sleep restriction, high workload increased local (occipital) sleep homeostasis, suggesting a use-dependent sleep response to visual work. We conclude that sleep restriction and cognitive workload interact to influence sleep homeostasis. Citation: Goel N, Abe T, Braun ME, Dinges DF. Cognitive workload and sleep restriction interact to influence sleep homeostatic responses. SLEEP 2014;37(11):1745-1756. PMID:25364070

Youth Screen Time and Behavioral Health Problems: The Role of Sleep Duration and Disturbances.

PubMed

Parent, Justin; Sanders, Wesley; Forehand, Rex

2016-05-01

The purpose of this study was to examine the indirect effect of youth screen time (e.g., television, computers, smartphones, video games, and tablets) on behavioral health problems (i.e., internalizing, externalizing, and peer problems) through sleep duration and disturbances. The authors assessed a community sample of parents with a child in one of the following three developmental stages: young childhood (3-7 yrs; N = 209), middle childhood (8-12 yrs; N = 202), and adolescence (13-17 yrs; N = 210). Path analysis was used to test the hypothesized indirect effect model. Findings indicated that, regardless of the developmental stage of the youth, higher levels of youth screen time were associated with more sleep disturbances, which, in turn, were linked to higher levels of youth behavioral health problems. Children who have increased screen time are more likely to have poor sleep quality and problem behaviors.

Circadian adaptation of airline pilots during extended duration operations between the USA and Asia.

PubMed

Gander, Philippa; van den Berg, Margo; Mulrine, Hannah; Signal, Leigh; Mangie, Jim

2013-10-01

This study tracked circadian adaptation among airline pilots before, during, and after trips where they flew from Seattle (SEA) or Los Angeles (LAX) to Asia (7--9 time zones westward), spent 7--12 d in Asia, and then flew back to the USA. In Asia, pilots' exposures to local time cues and sleep opportunities were constrained by duty (short-haul flights crossing ≤ 1 time zone/24 h). Fourteen captains and 16 first officers participated (median age = 56 versus 48 yrs, p.U) < 0.001). Their sleep was monitored (actigraphy, duty/sleep diaries) from 3 d pre-trip to 5 d post-trip. For every flight, Karolinska Sleepiness and Samn-Perelli Fatigue scales and 5-min psychomotor vigilance task (PVT) tests were completed pre-flight and at top of descent (TOD). Participants had ≥ 3 d free of duty prior to outbound flight(s). From 72--24 h prior to departure (baseline sleep), mean total sleep/24 h (TST) = 7.00 h (SD = 1.18 h) and mean sleep efficiency = 87% (SD = 4.9%). Most pilots (23/30) flew direct to and from Asia, but 7 LAX-based pilots flew via a 1-d layover in Honolulu (HNL). On flights with ≥ 2 pilots, mean total in-flight sleep varied from 0.40 to 2.09 h outbound and from 0.74 to 1.88 h inbound. Duty patterns in Asia were variable, with ≤ 2 flights/d (mean flight duration = 3.53 h, SD = 0.53 h). TST on days 17 in Asia did not differ from baseline (p.F) = 0.2031). However, mean sleep efficiency was significantly lower than baseline on days 5--7 (p.F) = 0.0041). More pilots were on duty between 20:00 and 24:00 h on days 57 (mean = 21%) than on days 24 (mean = 14%). Sleep propensity distribution phase markers and chi-square periodogram analyses suggest that adaptation to local time was complete by day 4 in Asia. On pre-flight PVT tests in Asia, the slowest 10% of responses improved for flights departing 14:00--19:59 h (p.F) = 0.0484). At TOD, the slowest 10% of responses improved across days for flights arriving 14:00--19:59 h (p.F) = 0.0349) and 20:00--01:59 h (p.F) = 0.0379). Sleepiness and fatigue ratings pre-flight and at TOD did not change across days in Asia. TST on post-trip day 1 was longer than baseline (estimated mean extension = 1.68 h; adjusted p(t) < 0.0001). On all post-trip days, sleep efficiency was comparable to baseline. Sleep propensity distribution phase markers and chi-square periodogram analyses suggest complete readaptation in 12 d. Two opposing influences appeared to affect sleep and PVT performance across days in Asia: progressive circadian adaptation to local time and increasing duty during local night, which displaced sleep from the optimal physiological time. Cumulative sleep restriction across the return flight may explain the large rebound in TST on day 1 post-trip. Thereafter TST, sleep efficiency, and sleep timing suggest that readaptation was complete. Rapid post-trip readaptation may be facilitated by pilots having unconstrained nocturnal sleep opportunities, coupled with stronger patterns of family and social cues than in Asia.

Human sleep and circadian rhythms: a simple model based on two coupled oscillators.

PubMed

Strogatz, S H

1987-01-01

We propose a model of the human circadian system. The sleep-wake and body temperature rhythms are assumed to be driven by a pair of coupled nonlinear oscillators described by phase variables alone. The novel aspect of the model is that its equations may be solved analytically. Computer simulations are used to test the model against sleep-wake data pooled from 15 studies of subjects living for weeks in unscheduled, time-free environments. On these tests the model performs about as well as the existing models, although its mathematical structure is far simpler.

Clinical and polysomnographic course of childhood narcolepsy with cataplexy.

PubMed

Pizza, Fabio; Franceschini, Christian; Peltola, Hanna; Vandi, Stefano; Finotti, Elena; Ingravallo, Francesca; Nobili, Lino; Bruni, Oliviero; Lin, Ling; Edwards, Mark J; Partinen, Markku; Dauvilliers, Yves; Mignot, Emmanuel; Bhatia, Kailash P; Plazzi, Giuseppe

2013-12-01

Our aim was to investigate the natural evolution of cataplexy and polysomnographic features in untreated children with narcolepsy with cataplexy. To this end, clinical, polysomnographic, and cataplexy-video assessments were performed at diagnosis (mean age of 10 ± 3 and disease duration of 1 ± 1 years) and after a median follow-up of 3 years from symptom onset (mean age of 12 ± 4 years) in 21 children with narcolepsy with cataplexy and hypocretin 1 deficiency (tested in 19 subjects). Video assessment was also performed in two control groups matched for age and sex at first evaluation and follow-up and was blindly scored for presence of hypotonic (negative) and active movements. Patients' data at diagnosis and at follow-up were contrasted, compared with controls, and related with age and disease duration. At diagnosis children with narcolepsy with cataplexy showed an increase of sleep time during the 24 h; at follow-up sleep time and nocturnal sleep latency shortened, in the absence of other polysomnographic or clinical (including body mass index) changes. Hypotonic phenomena and selected facial movements decreased over time and, tested against disease duration and age, appeared as age-dependent. At onset, childhood narcolepsy with cataplexy is characterized by an abrupt increase of total sleep over the 24 h, generalized hypotonia and motor overactivity. With time, the picture of cataplexy evolves into classic presentation (i.e., brief muscle weakness episodes triggered by emotions), whereas total sleep time across the 24 h decreases, returning to more age-appropriate levels.

Clinical and polysomnographic course of childhood narcolepsy with cataplexy

PubMed Central

Pizza, Fabio; Franceschini, Christian; Peltola, Hanna; Vandi, Stefano; Finotti, Elena; Ingravallo, Francesca; Nobili, Lino; Bruni, Oliviero; Lin, Ling; Edwards, Mark J.; Partinen, Markku; Dauvilliers, Yves; Mignot, Emmanuel; Bhatia, Kailash P.

2013-01-01

Our aim was to investigate the natural evolution of cataplexy and polysomnographic features in untreated children with narcolepsy with cataplexy. To this end, clinical, polysomnographic, and cataplexy-video assessments were performed at diagnosis (mean age of 10 ± 3 and disease duration of 1 ± 1 years) and after a median follow-up of 3 years from symptom onset (mean age of 12 ± 4 years) in 21 children with narcolepsy with cataplexy and hypocretin 1 deficiency (tested in 19 subjects). Video assessment was also performed in two control groups matched for age and sex at first evaluation and follow-up and was blindly scored for presence of hypotonic (negative) and active movements. Patients’ data at diagnosis and at follow-up were contrasted, compared with controls, and related with age and disease duration. At diagnosis children with narcolepsy with cataplexy showed an increase of sleep time during the 24 h; at follow-up sleep time and nocturnal sleep latency shortened, in the absence of other polysomnographic or clinical (including body mass index) changes. Hypotonic phenomena and selected facial movements decreased over time and, tested against disease duration and age, appeared as age-dependent. At onset, childhood narcolepsy with cataplexy is characterized by an abrupt increase of total sleep over the 24 h, generalized hypotonia and motor overactivity. With time, the picture of cataplexy evolves into classic presentation (i.e. brief muscle weakness episodes triggered by emotions), whereas total sleep time across the 24 h decreases, returning to more age-appropriate levels. PMID:24142146

Chronic Stress is Prospectively Associated with Sleep in Midlife Women: The SWAN Sleep Study

PubMed Central

Hall, Martica H.; Casement, Melynda D.; Troxel, Wendy M.; Matthews, Karen A.; Bromberger, Joyce T.; Kravitz, Howard M.; Krafty, Robert T.; Buysse, Daniel J.

2015-01-01

Study Objectives: Evaluate whether levels of upsetting life events measured over a 9-y period prospectively predict subjective and objective sleep outcomes in midlife women. Design: Prospective cohort study. Setting: Four sites across the United States. Participants: 330 women (46–57 y of age) enrolled in the Study of Women's Health Across the Nation (SWAN) Sleep Study. Interventions: N/A. Measurements and Results: Upsetting life events were assessed annually for up to 9 y. Trajectory analysis applied to life events data quantitatively identified three distinct chronic stress groups: low stress, moderate stress, and high stress. Sleep was assessed by self-report and in-home polysomnography (PSG) during the ninth year of the study. Multivariate analyses tested the prospective association between chronic stress group and sleep, adjusting for race, baseline sleep complaints, marital status, body mass index, symptoms of depression, and acute life events at the time of the Sleep Study. Women characterized by high chronic stress had lower subjective sleep quality, were more likely to report insomnia, and exhibited increased PSG-assessed wake after sleep onset (WASO) relative to women with low to moderate chronic stress profiles. The effect of chronic stress group on WASO persisted in the subsample of participants without baseline sleep complaints. Conclusions: Chronic stress is prospectively associated with sleep disturbance in midlife women, even after adjusting for acute stressors at the time of the sleep study and other factors known to disrupt sleep. These results are consistent with current models of stress that emphasize the cumulative effect of stressors on health over time. Citation: Hall MH, Casement MD, Troxel WM, Matthews KA, Bromberger JT, Kravitz HM, Krafty RT, Buysse DJ. Chronic stress is prospectively associated with sleep in midlife women: the SWAN Sleep Study. SLEEP 2015;38(10):1645–1654. PMID:26039965

Advancing the sleep/wake schedule impacts the sleep of African-Americans more than European-Americans.

PubMed

Paech, Gemma M; Crowley, Stephanie J; Fogg, Louis F; Eastman, Charmane I

2017-01-01

There are differences in sleep duration between Blacks/African-Americans and Whites/European-Americans. Recently, we found differences between these ancestry groups in the circadian system, such as circadian period and the magnitude of phase shifts. Here we document the role of ancestry on sleep and cognitive performance before and after a 9-h advance in the sleep/wake schedule similar to flying east or having a large advance in sleep times due to shiftwork, both of which produce extreme circadian misalignment. Non-Hispanic African and European-Americans (N = 20 and 17 respectively, aged 21-43 years) were scheduled to four baseline days each with 8 h time in bed based on their habitual sleep schedule. This sleep/wake schedule was then advanced 9 h earlier for three days. Sleep was monitored using actigraphy. During the last two baseline/aligned days and the first two advanced/misaligned days, beginning 2 h after waking, cognitive performance was measured every 3 h using the Automated Neuropsychological Assessment Metrics (ANAM) test battery. Mixed model ANOVAs assessed the effects of ancestry (African-American or European-American) and condition (baseline/aligned or advanced/misaligned) on sleep and cognitive performance. There was decreased sleep and impaired performance in both ancestry groups during the advanced/misaligned days compared to the baseline/aligned days. In addition, African-Americans obtained less sleep than European-Americans, especially on the first two days of circadian misalignment. Cognitive performance did not differ between African-Americans and European-Americans during baseline days. During the two advanced/misaligned days, however, African-Americans tended to perform slightly worse compared to European-Americans, particularly at times corresponding to the end of the baseline sleep episodes. Advancing the sleep/wake schedule, creating extreme circadian misalignment, had a greater impact on the sleep of African-Americans than European-Americans. Ancestry differences in sleep appear to be exacerbated when the sleep/wake schedule is advanced, which may have implications for individuals undertaking shiftwork and transmeridian travel.

Sleep Promotes the Extraction of Grammatical Rules

PubMed Central

Nieuwenhuis, Ingrid L. C.; Folia, Vasiliki; Forkstam, Christian; Jensen, Ole; Petersson, Karl Magnus

2013-01-01

Grammar acquisition is a high level cognitive function that requires the extraction of complex rules. While it has been proposed that offline time might benefit this type of rule extraction, this remains to be tested. Here, we addressed this question using an artificial grammar learning paradigm. During a short-term memory cover task, eighty-one human participants were exposed to letter sequences generated according to an unknown artificial grammar. Following a time delay of 15 min, 12 h (wake or sleep) or 24 h, participants classified novel test sequences as Grammatical or Non-Grammatical. Previous behavioral and functional neuroimaging work has shown that classification can be guided by two distinct underlying processes: (1) the holistic abstraction of the underlying grammar rules and (2) the detection of sequence chunks that appear at varying frequencies during exposure. Here, we show that classification performance improved after sleep. Moreover, this improvement was due to an enhancement of rule abstraction, while the effect of chunk frequency was unaltered by sleep. These findings suggest that sleep plays a critical role in extracting complex structure from separate but related items during integrative memory processing. Our findings stress the importance of alternating periods of learning with sleep in settings in which complex information must be acquired. PMID:23755173

Normal weight children have higher cognitive performance - Independent of physical activity, sleep, and diet.

PubMed

Hjorth, Mads F; Sørensen, Louise B; Andersen, Rikke; Dyssegaard, Camilla B; Ritz, Christian; Tetens, Inge; Michaelsen, Kim F; Astrup, Arne; Egelund, Niels; Sjödin, Anders

2016-10-15

Aside from the health consequences, observational studies indicate that being overweight may also negatively affect cognitive function. However, existing evidence has to a large extent not controlled for the possible confounding effect of having different lifestyles. Therefore, the objective was to examine the independent associations between weight status and lifestyle indicators with cognitive performance in 8-11year old Danish children. The analyses included 828 children (measured in 2011-2012) each having one to three measurement occasions separated by approximately 100days. Dietary intake, physical activity, sedentary time, and sleep duration were measured using dietary records and accelerometers. The Children's Sleep Habits Questionnaire was used to access sleep problems and the Andersen test was carried out to estimate cardio-respiratory fitness (CRF). Weight status (underweight, normal weight, and overweight/obese) was defined according to body mass index and cognitive performance was assessed using the d2-test of attention, a reading test, and a math test. A linear mixed model including a number of fixed and random effects was used to test associations between lifestyle indicators as well as BMI category and cognitive performance. After adjustment for demographics, socioeconomics, and multiple lifestyle indicators, normal weight children had higher cognitive test scores than overweight/obese and underweight children of up to 89% and 48% of expected learning within one school year (P<0.05). Daily breakfast consumption, fewer sleep problems, higher CRF, less total physical activity, more sedentary time, and less light physical activity were associated with higher cognitive performance independently of each other in at least one of the three cognitive tests (P<0.05). Normal weight children had higher cognitive performance compared to overweight/obese as well as underweight children, independent of multiple lifestyle indicators. Copyright © 2016 Elsevier Inc. All rights reserved.

The utility of a 5(th) nap in multiple sleep latency test.

PubMed

Muza, Rexford; Lykouras, Dimosthenis; Rees, Kate

2016-02-01

This is the first study that aimed to look specifically at the utility of the 5(th) nap in the multiple sleep latency test (MSLT), a test used to assist in the diagnosis of narcolepsy. Data was retrospectively collected from the Sleep Disorders Centre of a Tertiary Hospital on patients that had a 5(th) nap during their MSLT from the 08(th) November 2011 to 12(th) November 2014. Fifty-three patients had a 5(th) nap performed out of 378 MSLT studies. In 16% of cases a diagnosis of narcolepsy was given directly due to the inclusion of the 5(th) nap on the MSLT. Here a 5(th) nap allowed diagnostic criteria of mean sleep latency <8 minutes and >2 SOREMPS to be met. In 53% of cases the mean sleep latency increased due to 5(th) nap inclusion; the mean sleep latency of the first four naps was 5.6 vs. 6.7 after inclusion of the 5(th) nap. The 5(th) nap is not often performed within the MSLT studies. Our study shows that only a few patients may benefit from a 5(th) nap opportunity which also led to increase of the mean sleep latency at the expense of extra time, cost, labour and increased patient anxiety.

Sleep Strengthens but does Not Reorganize Memory Traces in a Verbal Creativity Task.

PubMed

Landmann, Nina; Kuhn, Marion; Maier, Jonathan-Gabriel; Feige, Bernd; Spiegelhalder, Kai; Riemann, Dieter; Nissen, Christoph

2016-03-01

Sleep after learning promotes the quantitative strengthening of new memories. Less is known about the impact of sleep on the qualitative reorganization of memory content. This study tested the hypothesis that sleep facilitates both memory strengthening and reorganization as indexed by a verbal creativity task. Sixty healthy university students (30 female, 30 male, 20-30 years) were investigated in a randomized, controlled parallel-group study with three experimental groups (sleep, sleep deprivation, daytime wakefulness). At baseline, 60 items of the Compound Remote Associate (CRA) task were presented. At retest after the experimental conditions, the same items were presented again together with 20 new control items to disentangle off-line incubation from online performance effects. Sleep significantly strengthened formerly encoded memories in comparison to both wake conditions (improvement in speed of correctly resolved items). Offline reorganization was not enhanced following sleep, but was enhanced following sleep-deprivation in comparison to sleep and daytime wakefulness (solution time of previously incubated, newly solved items). Online performance did not differ between the groups (solution time of new control items). The results support the notion that sleep promotes the strengthening, but not the reorganization, of newly encoded memory traces in a verbal creativity task. Future studies are needed to further determine the impact of sleep on different types of memory reorganization, such as associative thinking, creativity and emotional memory processing, and potential clinical translations, such as the augmentation of psychotherapy through sleep interventions. © 2016 Associated Professional Sleep Societies, LLC.

The Efficacy of Melatonin for Sleep Problems in Children with Autism, Fragile X Syndrome, or Autism and Fragile X Syndrome

PubMed Central

Wirojanan, Juthamas; Jacquemont, Sebastien; Diaz, Rafael; Bacalman, Susan; Anders, Thomas F.; Hagerman, Randi J.; Goodlin-Jones, Beth L.

2009-01-01

Study Objective: To determine the efficacy of melatonin on sleep problems in children with autistic spectrum disorder (ASD) and fragile X syndrome (FXS). Methods: A 4-week, randomized, double blind, placebo-controlled, crossover design was conducted following a 1-week baseline period. Either melatonin, 3 mg, or placebo was given to participants for 2 weeks and then alternated for another 2 weeks. Sleep variables, including sleep duration, sleep-onset time, sleep-onset latency time, and the number of night awakenings, were recorded using an Actiwatch and from sleep diaries completed by parents. All participants had been thoroughly assessed for ASD and also had DNA testing for the diagnosis of FXS. Results: Data were successfully obtained from the 12 of 18 subjects who completed the study (11 males, age range 2 to 15.25 years, mean 5.47, SD 3.6). Five participants met diagnostic criteria for ASD, 3 for FXS alone, 3 for FXS and ASD, and 1 for fragile X premutation. Eight out of 12 had melatonin first. The conclusions from a nonparametric repeated-measures technique indicate that mean night sleep duration was longer on melatonin than placebo by 21 minutes (p = .02), mean sleep-onset latency was shorter by 28 minutes (p = .0001), and mean sleep-onset time was earlier by 42 minutes (p = .02). Conclusion: The results of this study support the efficacy and tolerability of melatonin treatment for sleep problems in children with ASD and FXS. Citation: Wirojanan J; Jacquemont S; Diaz R; Bacalman S; Anders TF; Hagerman RJ; Goodlin-Jones BL. The Efficacy of Melatonin for Sleep Problems in Children with Autism, Fragile X Syndrome, or Autism and Fragile X Syndrome. J Clin Sleep Med 2009;5(2):145-150. PMID:19968048

A 2-night, 3-period, crossover study of ramelteon's efficacy and safety in older adults with chronic insomnia.

PubMed

Roth, Thomas; Seiden, David; Wang-Weigand, Sherry; Zhang, Jeffrey

2007-05-01

To assess the efficacy and safety of ramelteon, a selective melatonin MT1/MT2-receptor agonist, for insomnia treatment in older adults. In a randomized, 9-week, 3-period crossover trial conducted at 17 sleep centers, older adults (N = 100) with chronic primary insomnia (37 men, 63 women; mean age [range], 70.7 [65-83] years) were administered placebo, ramelteon 4 mg, and ramelteon 8 mg in three treatment phases for two consecutive nights. Each phase was separated by 5- to 12-day washout periods. Sleep was monitored via polysomnography. Subjective sleep parameters, using a Postsleep Questionnaire, were recorded, and residual pharmacologic effects were assessed. Statistically significant reductions in latency to persistent sleep were observed with both ramelteon 4 mg and 8 mg compared to placebo (28.7 min vs. 38.4 min, p < 0.001; 30.8 min vs. 38.4 min, p = 0.005, respectively). Total sleep time (p = 0.036 and p = 0.007, respectively) and sleep efficiency (p = 0.037 and p = 0.007, respectively) were also significantly improved with ramelteon 4 mg and 8 mg compared to placebo. Statistically significant reductions in subjective sleep latency on a Postsleep Questionnaire were reported with ramelteon 4 mg versus placebo (p = 0.037), but not ramelteon 8 mg (p = 0.120); no significant differences on other subjective sleep assessments were reported. A lack of power limits interpretation of self-reported sleep parameters. Incidences of adverse events considered treatment related were placebo (7%), ramelteon 4 mg (11%), and ramelteon 8 mg (5%). No residual pharmacologic effects were observed via Digit Symbol Substitution Test, memory recall tests (immediate and delayed), visual analog scales (feelings and mood), and Postsleep Questionnaire (level of alertness and ability to concentrate). In older adults with chronic primary insomnia, ramelteon produced significant reductions in latency to persistent sleep and increases in total sleep time and sleep efficacy, and showed no evidence of adverse next-day psychomotor or cognitive effects.

Sleep quality but not sleep quantity effects on cortisol responses to acute psychosocial stress

PubMed Central

Bassett, Sarah M.; Lupis, Sarah B.; Gianferante, Danielle; Rohleder, Nicolas; Wolf, Jutta M.

2016-01-01

Given the well-documented deleterious health effects, poor sleep has become a serious public health concern and increasing efforts are directed towards understanding underlying pathways. One potential mechanism may be stress and its biological correlates; however, studies investigating the effects of poor sleep on a body’s capacity to deal with challenges are lacking. The current study thus aimed at testing the effects of sleep quality and sleep quantity on cortisol responses to acute psychosocial stress. A total of 73 college-aged adults (44 females) were investigated. Self-reported sleep behavior was assessed via the Pittsburgh Sleep Quality Index and salivary cortisol responses to the Trier Social Stress Test (TSST) were measured. In terms of sleep quality, we found a significant three-way interaction, such that relative to bad sleep quality, men who reported fairly good or very good sleep quality showed blunted or exaggerated cortisol responses, respectively, while women’s stress responses were less dependent on their self-reported sleep quality. Contrarily, average sleep duration did not appear to impact cortisol stress responses. Lastly, participants who reported daytime dysfunctions (i.e., having trouble staying awake or keeping up enthusiasm) also showed a trend to blunted cortisol stress responses compared to participants who did not experience these types of daytime dysfunctions. Overall, the current study suggests gender-specific stress reactivity dysfunctions as one mechanism linking poor sleep with detrimental physical health outcomes. Furthermore, the observed differential sleep effects may indicate that while the body may be unable to maintain normal HPA functioning in an acute psychosocial stress situation after falling prey to low sleep quality, it may retain capacities to deal with challenges during extended times of sleep deprivation. PMID:26414625

Differential diagnosis in hypersomnia.

PubMed

Dauvilliers, Yves

2006-03-01

Hypersomnia includes a group of disorders in which the primary complaint is excessive daytime sleepiness. Chronic hypersomnia is characterized by at least 3 months of excessive sleepiness prior to diagnosis and may affect 4% to 6% of the population. The severity of daytime sleepiness needs to be quantified by subjective scales (at least the Epworth sleepiness scale) and objective tests such as the multiple sleep latency test. Chronic hypersomnia does not correspond to an individual clinical entity but includes numerous different etiologies of hypersomnia as recently reported in the revised International Classification of Sleep Disorders. This review details most of those disorders, including narcolepsy with and without cataplexy, idiopathic hypersomnia with and without long sleep time, recurrent hypersomnia, behaviorally induced insufficient sleep syndrome, hypersomnia due to medical condition, hypersomnia due to drug or substance, hypersomnia not due to a substance or known physiologic condition, and also sleep-related disordered breathing and periodic leg movement disorders.

Sleep promotes analogical transfer in problem solving.

PubMed

Monaghan, Padraic; Sio, Ut Na; Lau, Sum Wai; Woo, Hoi Kei; Linkenauger, Sally A; Ormerod, Thomas C

2015-10-01

Analogical problem solving requires using a known solution from one problem to apply to a related problem. Sleep is known to have profound effects on memory and information restructuring, and so we tested whether sleep promoted such analogical transfer, determining whether improvement was due to subjective memory for problems, subjective recognition of similarity across related problems, or by abstract generalisation of structure. In Experiment 1, participants were exposed to a set of source problems. Then, after a 12-h period involving sleep or wake, they attempted target problems structurally related to the source problems but with different surface features. Experiment 2 controlled for time of day effects by testing participants either in the morning or the evening. Sleep improved analogical transfer, but effects were not due to improvements in subjective memory or similarity recognition, but rather effects of structural generalisation across problems. Copyright © 2015 Elsevier B.V. All rights reserved.

Sleep Quantity and Quality during Acute Concussion: A Pilot Study

PubMed Central

Raikes, Adam C.; Schaefer, Sydney Y.

2016-01-01

Study Objectives: A number of subjective and objective studies provide compelling evidence of chronic post-concussion changes in sleep, yet very little is known about the acute effects of concussion on sleep quality and quantity. Therefore, the purpose of this prospective pilot study was to use actigraphy to examine the changes in sleep quality and quantity acutely following concussion at home rather than in a hospital or sleep laboratory. Methods: Seventeen young adults (7 with acute concussion, 10 controls) were recruited for this study. All participants completed two 5-day testing sessions separated by 30 days from intake (controls) or day of injury (concussion). Participants wore actigraphs and kept a sleep journal. Sleep parameter outcomes included nighttime total sleep time (nTST), 24-h total sleep time (TST), wake after sleep onset (WASO), and sleep efficiency (SE). The coefficient of variation (CV) for each sleep parameter was computed for each session. Results: nTST and TST CV was significantly greater in the concussion group. There is the additional indication that individuals with a concussion may require and obtain more sleep shortly after injury and subsequently have a shorter duration of sleep at 1 mo post-injury. This pattern was not seen in the measures of sleep quality (WASO, SE). Conclusions: Individuals with a concussion demonstrated increased nighttime sleep duration variability. This increase persisted at 1 mo post-injury and may be associated with previously documented self-reports of poor sleep quality lasting months and years after a concussion. Additionally, this increase may predispose individuals to numerous negative health outcomes if left untreated. Citation: Raikes AC, Schaefer SY. Sleep quantity and quality during acute concussion: a pilot study. SLEEP 2016;39(12):2141–2147. PMID:27748242

Lost sleep and cyberloafing: Evidence from the laboratory and a daylight saving time quasi-experiment.

PubMed

Wagner, David T; Barnes, Christopher M; Lim, Vivien K G; Ferris, D Lance

2012-09-01

The Internet is a powerful tool that has changed the way people work. However, the ubiquity of the Internet has led to a new workplace threat to productivity-cyberloafing. Building on the ego depletion model of self-regulation, we examine how lost and low-quality sleep influence employee cyberloafing behaviors and how individual differences in conscientiousness moderate these effects. We also demonstrate that the shift to Daylight Saving Time (DST) results in a dramatic increase in cyberloafing behavior at the national level. We first tested the DST-cyberloafing relation through a national quasi-experiment, then directly tested the relation between sleep and cyberloafing in a closely controlled laboratory setting. We discuss the implications of our findings for theory, practice, and future research.

Validation of sleep-2-Peak: A smartphone application that can detect fatigue-related changes in reaction times during sleep deprivation.

PubMed

Brunet, Jean-François; Dagenais, Dominique; Therrien, Marc; Gartenberg, Daniel; Forest, Geneviève

2017-08-01

Despite its high sensitivity and validity in the context of sleep loss, the Psychomotor Vigilance Test (PVT) could be improved. The aim of the present study was to validate a new smartphone PVT-type application called sleep-2-Peak (s2P) by determining its ability to assess fatigue-related changes in alertness in a context of extended wakefulness. Short 3-min versions of s2P and of the classic PVT were administered at every even hour during a 35-h total sleep deprivation protocol. In addition, subjective measures of sleepiness were collected. The outcomes on these tests were then compared using Pearson product-moment correlations, t tests, and repeated measures within-groups analyses of variance. The results showed that both tests significantly correlated on all outcome variables, that both significantly distinguished between the alert and sleepy states in the same individual, and that both varied similarly through the sleep deprivation protocol as sleep loss accumulated. All outcome variables on both tests also correlated significantly with the subjective measures of sleepiness. These results suggest that a 3-min version of s2P is a valid tool for differentiating alert from sleepy states and is as sensitive as the PVT for tracking fatigue-related changes during extended wakefulness and sleep loss. Unlike the PVT, s2P does not provide feedback to subjects on each trial. We discuss how this feature of s2P raises the possibility that the performance results measured by s2P could be less impacted by motivational confounds, giving this tool added value in particular clinical and/or research settings.

The Clinical Validation of the Athlete Sleep Screening Questionnaire: an Instrument to Identify Athletes that Need Further Sleep Assessment.

PubMed

Bender, Amy M; Lawson, Doug; Werthner, Penny; Samuels, Charles H

2018-06-04

Previous research has established that general sleep screening questionnaires are not valid and reliable in an athlete population. The Athlete Sleep Screening Questionnaire (ASSQ) was developed to address this need. While the initial validation of the ASSQ has been established, the clinical validity of the ASSQ has yet to be determined. The main objective of the current study was to evaluate the clinical validity of the ASSQ. Canadian National Team athletes (N = 199; mean age 24.0 ± 4.2 years, 62% females; from 23 sports) completed the ASSQ. A subset of athletes (N = 46) were randomized to the clinical validation sub-study which required subjects to complete an ASSQ at times 2 and 3 and to have a clinical sleep interview by a sleep medicine physician (SMP) who rated each subjects' category of clinical sleep problem and provided recommendations to improve sleep. To assess clinical validity, the SMP category of clinical sleep problem was compared to the ASSQ. The internal consistency (Cronbach's alpha = 0.74) and test-retest reliability (r = 0.86) of the ASSQ were acceptable. The ASSQ demonstrated good agreement with the SMP (Cohen's kappa = 0.84) which yielded a diagnostic sensitivity of 81%, specificity of 93%, positive predictive value of 87%, and negative predictive value of 90%. There were 25.1% of athletes identified to have clinically relevant sleep disturbances that required further clinical sleep assessment. Sleep improved from time 1 at baseline to after the recommendations at time 3. Sleep screening athletes with the ASSQ provides a method of accurately determining which athletes would benefit from preventative measures and which athletes suffer from clinically significant sleep problems. The process of sleep screening athletes and providing recommendations improves sleep and offers a clinical intervention output that is simple and efficient for teams and athletes to implement.

The Effect of One Night's Sleep Deprivation on Adolescent Neurobehavioral Performance

PubMed Central

Louca, Mia; Short, Michelle A.

2014-01-01

Study Objectives: To investigate the effects of one night's sleep deprivation on neurobehavioral functioning in adolescents. Design: Participants completed a neurobehavioral test battery measuring sustained attention, reaction speed, cognitive processing speed, sleepiness, and fatigue every 2 h during wakefulness. Baseline performance (defined as those test bouts between 09:00 and 19:00 on days 2 and 3, following two 10-h sleep opportunities) were compared to performance at the same clock time the day following total sleep deprivation. Setting: The sleep laboratory at the Centre for Sleep Research. Participants: Twelve healthy adolescents (6 male), aged 14-18 years (mean = 16.17, standard deviation = 0.83). Measurements and Results: Sustained attention, reaction speed, cognitive processing speed, and subjective sleepiness were all significantly worse following one night without sleep than following 10-h sleep opportunities (all main effects of day, P < 0.05). Sleep deprivation led to increased variability on objective performance measures. There were between-subjects differences in response to sleep loss that were task-specific, suggesting that adolescents may not only vary in terms of the degree to which they are affected by sleep loss but also the domains in which they are affected. Conclusions: These findings suggest that one night of total sleep deprivation has significant deleterious effects upon neurobehavioral performance and subjective sleepiness. These factors impair daytime functioning in adolescents, leaving them at greater risk of poor academic and social functioning and accidents and injuries. Citation: Louca M, Short MA. The effect of one night's sleep deprivation on adolescent neurobehavioral performance. SLEEP 2014;37(11):1799-1807. PMID:25364075

Development of the athlete sleep behavior questionnaire: A tool for identifying maladaptive sleep practices in elite athletes

PubMed Central

Driller, Matthew W; Mah, Cheri D; Halson, Shona L

2018-01-01

Introduction Existing sleep questionnaires to assess sleep behaviors may not be sensitive in determining the unique sleep challenges faced by elite athletes. The purpose of the current study was to develop and validate the Athlete Sleep Behavior Questionnaire (ASBQ) to be used as a practical tool for support staff working with elite athletes. Methods 564 participants (242 athletes, 322 non-athletes) completed the 18-item ASBQ and three previously validated questionnaires; the Sleep Hygiene Index (SHI), the Epworth Sleepiness Scale (ESS) and the Pittsburgh Sleep Quality Index (PSQI). A cohort of the studied population performed the ASBQ twice in one week to assess test-retest reliability, and also performed sleep monitoring via wrist-actigraphy. Results Comparison of the ASBQ with existing sleep questionnaires resulted in moderate to large correlations (r=0.32 - 0.69). There was a significant difference between athletes and non-athletes for the ASBQ global score (44±6 vs. 41±6, respectively, p<0.01) and for the PSQI, but not for the SHI or the ESS. The reliability of the ASBQ was acceptable (ICC=0.87) when re-tested within 7 days. There was a moderate relationship between ASBQ and total sleep time (r=-0.42). Conclusion The ASBQ is a valid and reliable tool that can differentiate the sleep practices between athletes and non-athletes, and offers a practical instrument for practitioners and/or researchers wanting to evaluate the sleep behaviors of elite athletes. The ASBQ may provide information on areas where improvements to individual athletes’ sleep habits could be made. PMID:29796200

The inappropriate occurrence of rapid eye movement sleep in narcolepsy is not due to a defect in homeostatic regulation of rapid eye movement sleep.

PubMed

Roman, Alexis; Meftah, Soraya; Arthaud, Sébastien; Luppi, Pierre-Hervé; Peyron, Christelle

2018-06-01

Narcolepsy type 1 is a disabling disorder with four primary symptoms: excessive-daytime-sleepiness, cataplexy, hypnagogic hallucinations, and sleep paralysis. The later three symptoms together with a short rapid eye movement (REM) sleep latency have suggested impairment in REM sleep homeostatic regulation with an enhanced propensity for (i.e. tendency to enter) REM sleep. To test this hypothesis, we challenged REM sleep homeostatic regulation in a recognized model of narcolepsy, the orexin knock-out (Orex-KO) mice and their wild-type (WT) littermates. We first performed 48 hr of REM sleep deprivation using the classic small-platforms-over-water method. We found that narcoleptic mice are similarly REM sleep deprived to WT mice. Although they had shorter sleep latency, Orex-KO mice recovered similarly to WT during the following 10 hr of recovery. Interestingly, Orex-KO mice also had cataplexy episodes immediately after REM sleep deprivation, anticipating REM sleep rebound, at a time of day when cataplexy does not occur in baseline condition. We then evaluated REM sleep propensity using our new automated method of deprivation that performs a specific and efficient REM sleep deprivation. We showed that REM sleep propensity is similar during light phase in Orex-KO and WT mice. However, during the dark phase, REM sleep propensity was not suppressed in Orex-KO mice when hypocretin/orexin neuropeptides are normally released. Altogether our data suggest that in addition to the well-known wake-promoting role of hypocretin/orexin, these neuropeptides would also suppress REM sleep. Therefore, hypocretin/orexin deficiency would facilitate the occurrence of REM sleep at any time of day in an opportunistic manner as seen in human narcolepsy.

Daytime REM Sleep in Parkinson’s Disease

PubMed Central

Bliwise, Donald L.; Trotti, Lynn Marie; Juncos, Jorge J.; Factor, Stewart A.; Freeman, Alan; Rye, David B.

2012-01-01

Background Previous studies have demonstrated both clinical and neurochemical similarities between Parkinson’s disease (PD) and narcolepsy. The intrusion of REM sleep into the daytime remains a cardinal feature of narcolepsy, but the importance of these intrusions in PD remains unclear. In this study we examined REM sleep during daytime Maintenance of Wakefulness Testing (MWT) in PD patients. Methods Patients spent 2 consecutive nights and days in the sleep laboratory. During the daytime, we employed a modified MWT procedure in which each daytime nap opportunity (4 per day) was extended to 40 minutes, regardless of whether the patient was able to sleep or how much the patient slept. We examined each nap opportunity for the presence of REM sleep and time to fall asleep. Results Eleven of 63 PD patients studied showed 2 or more REM episodes and 10 showed 1 REM episode on their daytime MWTs. Nocturnal sleep characteristics and sleep disorders were unrelated to the presence of daytime REM sleep, however, patients with daytime REM were significantly sleepier during the daytime than those patients without REM. Demographic and clinical variables, including Unified Parkinson’s Disease Rating Scale motor scores and levodopa dose equivalents, were unrelated to the presence of REM sleep. Conclusions A sizeable proportion of PD patients demonstrated REM sleep and daytime sleep tendency during daytime nap testing. These data confirm similarities in REM intrusions between narcolepsy and PD, perhaps suggesting parallel neurodegenerative conditions of hypocretin deficiency. PMID:22939103

Sleep quality but not sleep quantity effects on cortisol responses to acute psychosocial stress.

PubMed

Bassett, Sarah M; Lupis, Sarah B; Gianferante, Danielle; Rohleder, Nicolas; Wolf, Jutta M

2015-01-01

Given the well-documented deleterious health effects, poor sleep has become a serious public health concern and increasing efforts are directed toward understanding underlying pathways. One potential mechanism may be stress and its biological correlates; however, studies investigating the effects of poor sleep on a body's capacity to deal with challenges are lacking. The current study thus aimed at testing the effects of sleep quality and quantity on cortisol responses to acute psychosocial stress. A total of 73 college-aged adults (44 females) were investigated. Self-reported sleep behavior was assessed via the Pittsburgh Sleep Quality Index and salivary cortisol responses to the Trier Social Stress Test were measured. In terms of sleep quality, we found a significant three-way interaction, such that relative to bad sleep quality, men who reported fairly good or very good sleep quality showed blunted or exaggerated cortisol responses, respectively, while women's stress responses were less dependent on their self-reported sleep quality. Contrarily, average sleep duration did not appear to impact cortisol stress responses. Lastly, participants who reported daytime dysfunctions (i.e. having trouble staying awake or keeping up enthusiasm) also showed a trend to blunted cortisol stress responses compared to participants who did not experience these types of daytime dysfunctions. Overall, the current study suggests gender-specific stress reactivity dysfunctions as one mechanism linking poor sleep with detrimental physical health outcomes. Furthermore, the observed differential sleep effects may indicate that while the body may be unable to maintain normal hypothalamic-pituitary-adrenal functioning in an acute psychosocial stress situation after falling prey to low sleep quality, it may retain capacities to deal with challenges during extended times of sleep deprivation.

The effects of low-intensity cycling on cognitive performance following sleep deprivation.

PubMed

Slutsky, Alexis B; Diekfuss, Jed A; Janssen, James A; Berry, Nate T; Shih, Chia-Hao; Raisbeck, Louisa D; Wideman, Laurie; Etnier, Jennifer L

2017-10-15

This study examined the effect of 24h of sleep deprivation on cognitive performance and assessed the effect of acute exercise on cognitive performance following sleep deprivation. Young, active, healthy adults (n=24, 14 males) were randomized to control (age=24.7±3.7years, BMI=27.2±7.0) or exercise (age=25.3±3.3years, BMI=25.6±5.1) groups. Cognitive testing included a 5-min psychomotor vigilance task (PVT), three memory tasks with increasing cognitive load, and performance of the PVT a second time. On morning one, cognitive testing followed a typical night's sleep. Following 24-h of sustained wakefulness, cognitive testing was conducted again prior to and after the acute intervention. Participants in the exercise condition performed low-intensity cycling (∼40%HRR) for 15-min and those in the control condition sat quietly on the bike for 15-min. t-Tests revealed sleep deprivation negatively affected performance on the PVT, but did not affect memory performance. Following the acute intervention, there were no cognitive performance differences between the exercise and rested conditions. We provide support for previous literature suggesting that during simple tasks, sleep deprivation has negative effects on cognitive performance. Importantly, in contrast to previous literature which has shown multiple bouts of exercise adding to cognitive detriment when combined with sleep deprivation, our results did not reveal any further detriments to cognitive performance from a single-bout of exercise following sleep deprivation. Copyright © 2017 Elsevier Inc. All rights reserved.

A Cross-Cultural Comparison of Sleep Duration between U.S. and Australian Adolescents: The Effect of School Start Time, Parent-Set Bedtimes, and Extracurricular Load

ERIC Educational Resources Information Center

Short, Michelle A.; Gradisar, Michael; Lack, Leon C.; Wright, Helen R.; Dewald, Julia F.; Wolfson, Amy R.; Carskadon, Mary A.

2013-01-01

Study Objective. To test whether sleep duration on school nights differs between adolescents in Australia and the United States and, if so, whether this difference is explained by cultural differences in school start time, parental involvement in setting bedtimes, and extracurricular commitments. Participants. Three hundred eighty-five adolescents…

The interaction between sleep quality and academic performance.

PubMed

Ahrberg, K; Dresler, M; Niedermaier, S; Steiger, A; Genzel, L

2012-12-01

Sleep quality has significant effects on cognitive performance and is influenced by multiple factors such as stress. Contrary to the ideal, medical students and residents suffer from sleep deprivation and stress at times when they should achieve the greatest amount of learning. In order to examine the relationship between sleep quality and academic performance, 144 medical students undertaking the pre-clinical board exam answered a survey regarding their subjective sleep quality (Pittsburgh sleep quality index, PSQI), grades and subjective stress for three different time points: semester, pre- and post-exam. Academic performance correlated with stress and sleep quality pre-exam (r = 0.276, p < 0.001 and r = 0.158, p < 0.03, note that low performance meant low sleep quality and high stress), however not with the stress or sleep quality during the semester and post-exam. 59% of all participants exhibited clinically relevant sleep disturbances (PSQI > 5) during exam preparation compared to 29% during the semester and 8% post-exam. This study shows that in medical students it is not the generally poor sleepers, who perform worse in the medical board exams. Instead students who will perform worse on their exams seem to be more stressed and suffer from poor sleep quality. However, poor sleep quality may negatively impact test performance as well, creating a vicious circle. Furthermore, the rate of sleep disturbances in medical students should be cause for intervention. Copyright © 2012 Elsevier Ltd. All rights reserved.

Measures of sleep and cardiac functioning during sleep using a multi-sensory commercially-available wristband in adolescents.

PubMed

de Zambotti, Massimiliano; Baker, Fiona C; Willoughby, Adrian R; Godino, Job G; Wing, David; Patrick, Kevin; Colrain, Ian M

2016-05-01

To validate measures of sleep and heart rate (HR) during sleep generated by a commercially-available activity tracker against those derived from polysomnography (PSG) in healthy adolescents. Sleep data were concurrently recorded using FitbitChargeHR™ and PSG, including electrocardiography (ECG), during an overnight laboratory sleep recording in 32 healthy adolescents (15 females; age, mean±SD: 17.3±2.5years). Sleep and HR measures were compared between FitbitChargeHR™ and PSG using paired t-tests and Bland-Altman plots. Epoch-by-epoch analysis showed that FitbitChargeHR™ had high overall accuracy (91%), high sensitivity (97%) in detecting sleep, and poor specificity (42%) in detecting wake on a min-to-min basis. On average, FitbitChargeHR™ significantly but negligibly overestimated total sleep time by 8min and sleep efficiency by 1.8%, and underestimated wake after sleep onset by 5.6min (p<0.05). Within FitbitChargeHR™ epochs of sleep, the average HR was 59.3±7.5bpm, which was significantly but negligibly lower than that calculated from ECG (60.2±7.6bpm, p<0.001), with no change in mean discrepancies throughout the night. FitbitChargeHR™ showed good agreement with PSG and ECG in measuring sleep and HR during sleep, supporting its use in assessing sleep and cardiac function in healthy adolescents. Further validation is needed to assess its reliability over prolonged periods of time in ecological settings and in clinical populations. Copyright © 2016 Elsevier Inc. All rights reserved.

Measures of Sleep and Cardiac Functioning During Sleep Using a Multi-Sensory Commercially–Available Wristband in Adolescents

PubMed Central

de Zambotti, Massimiliano; Baker, Fiona C.; Willoughby, Adrian R.; Godino, Job G.; Wing, David; Patrick, Kevin; Colrain, Ian M.

2016-01-01

To validate measures of sleep and heart rate (HR) during sleep generated by a commercially-available activity tracker against those derived from polysomnography (PSG) in healthy adolescents. Sleep data were concurrently recorded using FitbitChargeHR™ and PSG, including electrocardiography (ECG), during an overnight laboratory sleep recording in 32 healthy adolescents (15 females; Age, mean±SD: 17.3±2.5 years). Sleep and HR measures were compared between FitbitChargeHR™ and PSG using paired t-tests and Bland-Altman plots. Epoch-by-epoch analysis showed that FitbitChargeHR™ had high overall accuracy (91%), high sensitivity (97%) in detecting sleep, and poor specificity (42%) in detecting wake on a min-to-min basis. On average, FitbitChargeHR™ significantly but negligibly overestimated total sleep time by 8min and sleep efficiency by 1.8%, and underestimated wake after sleep onset by 5.6min (p<0.05). Within FitbitChargeHR™ epochs of sleep, the average HR was 59.3±7.5 bpm, which was significantly but negligibly lower than that calculated from ECG (60.2±7.6 bpm, p<0.001), with no change in mean discrepancies throughout the night. FitbitChargeHR™ showed good agreement with PSG and ECG in measuring sleep and HR during sleep, supporting its use in assessing sleep and cardiac function in healthy adolescents. Further validation is needed to assess its reliability over prolonged periods of time in ecological settings and in clinical populations. PMID:26969518

Grouped comparisons of sleep quality for new and personal bedding systems.

PubMed

Jacobson, Bert H; Wallace, Tia J; Smith, Doug B; Kolb, Tanner

2008-03-01

The purpose of this study was to compare sleep comfort and quality between personal and new bedding systems. A convenience sample (women, n=33; men, n=29) with no clinical history of disturbed sleep participated in the study. Subjects recorded back and shoulder pain, sleep quality, comfort, and efficiency for 28 days each in their personal beds (pre) and in new medium-firm bedding systems (post). Repeated measures ANOVAs revealed significant improvement between pre- and post-test means for all dependent variables. Furthermore, reduction of pain and stiffness and improvement of sleep comfort and quality became more prominent over time. No significant differences were found for the groupings of age, weight, height, or body mass index. It was found that for the cheapest category of beds, lower back pain was significantly (p<0.01) more prominent than for the medium and higher priced beds. Average bed age was 9.5yrs. It was concluded that new bedding systems can significantly improve selected sleep variables and that continuous sleep quality may be dependent on timely replacement of bedding systems.

Maximizing sensitivity of the psychomotor vigilance test (PVT) to sleep loss.

PubMed

Basner, Mathias; Dinges, David F

2011-05-01

The psychomotor vigilance test (PVT) is among the most widely used measures of behavioral alertness, but there is large variation among published studies in PVT performance outcomes and test durations. To promote standardization of the PVT and increase its sensitivity and specificity to sleep loss, we determined PVT metrics and task durations that optimally discriminated sleep deprived subjects from alert subjects. Repeated-measures experiments involving 10-min PVT assessments every 2 h across both acute total sleep deprivation (TSD) and 5 days of chronic partial sleep deprivation (PSD). Controlled laboratory environment. 74 healthy subjects (34 female), aged 22-45 years. TSD experiment involving 33 h awake (N = 31 subjects) and a PSD experiment involving 5 nights of 4 h time in bed (N = 43 subjects). In a paired t-test paradigm and for both TSD and PSD, effect sizes of 10 different PVT performance outcomes were calculated. Effect sizes were high for both TSD (1.59-1.94) and PSD (0.88-1.21) for PVT metrics related to lapses and to measures of psychomotor speed, i.e., mean 1/RT (response time) and mean slowest 10% 1/RT. In contrast, PVT mean and median RT outcomes scored low to moderate effect sizes influenced by extreme values. Analyses facilitating only portions of the full 10-min PVT indicated that for some outcomes, high effect sizes could be achieved with PVT durations considerably shorter than 10 min, although metrics involving lapses seemed to profit from longer test durations in TSD. Due to their superior conceptual and statistical properties and high sensitivity to sleep deprivation, metrics involving response speed and lapses should be considered primary outcomes for the 10-min PVT. In contrast, PVT mean and median metrics, which are among the most widely used outcomes, should be avoided as primary measures of alertness. Our analyses also suggest that some shorter-duration PVT versions may be sensitive to sleep loss, depending on the outcome variable selected, although this will need to be confirmed in comparative analyses of separate duration versions of the PVT. Using both sensitive PVT metrics and optimal test durations maximizes the sensitivity of the PVT to sleep loss and therefore potentially decreases the sample size needed to detect the same neurobehavioral deficit. We propose criteria to better standardize the 10-min PVT and facilitate between-study comparisons and meta-analyses.

The Effects of Modafinil and OTC Stimulants on Physical and Cognitive Performance

DTIC Science & Technology

2016-03-07

least 7 hours per night were either rescheduled until the sleep requirements were met or dropped from the study. 2.1.3 Vision testing. Vision...the study. Those potential participants who did not sleep at least 7 hours per night were either rescheduled until the sleep requirements were met...could not reschedule another time to return. Therefore, 19 individuals completed the study. One participant’s data indicated poor compliance with

Trajectories of sleep disturbance and daytime sleepiness in women before and after surgery for breast cancer.

PubMed

Van Onselen, Christina; Paul, Steven M; Lee, Kathryn; Dunn, Laura; Aouizerat, Bradley E; West, Claudia; Dodd, Marylin; Cooper, Bruce; Miaskowski, Christine

2013-02-01

Sleep disturbance is a problem for oncology patients. To evaluate how sleep disturbance and daytime sleepiness (DS) changed from before to six months following surgery and whether certain characteristics predicted initial levels and/or the trajectories of these parameters. Patients (n=396) were enrolled prior to surgery and completed monthly assessments for six months following surgery. The General Sleep Disturbance Scale was used to assess sleep disturbance and DS. Using hierarchical linear modeling, demographic, clinical, symptom, and psychosocial adjustment characteristics were evaluated as predictors of initial levels and trajectories of sleep disturbance and DS. All seven General Sleep Disturbance Scale scores were above the cutoff for clinically meaningful levels of sleep disturbance. Lower performance status; higher comorbidity, attentional fatigue, and physical fatigue; and more severe hot flashes predicted higher preoperative levels of sleep disturbance. Higher levels of education predicted higher sleep disturbance scores over time. Higher levels of depressive symptoms predicted higher preoperative levels of sleep disturbance, which declined over time. Lower performance status; higher body mass index; higher fear of future diagnostic tests; not having had sentinel lymph node biopsy; having had an axillary lymph node dissection; and higher depression, physical fatigue, and attentional fatigue predicted higher DS prior to surgery. Higher levels of education, not working for pay, and not having undergone neo-adjuvant chemotherapy predicted higher DS scores over time. Sleep disturbance is a persistent problem for patients with breast cancer. The effects of interventions that can address modifiable risk factors need to be evaluated. Copyright © 2013 U.S. Cancer Pain Relief Committee. Published by Elsevier Inc. All rights reserved.

Baseline neurocognitive testing in sports-related concussions: the importance of a prior night's sleep.

PubMed

McClure, D Jake; Zuckerman, Scott L; Kutscher, Scott J; Gregory, Andrew J; Solomon, Gary S

2014-02-01

The management of sports-related concussions (SRCs) utilizes serial neurocognitive assessments and self-reported symptom inventories to assess recovery and safety for return to play (RTP). Because postconcussive RTP goals include symptom resolution and a return to neurocognitive baseline levels, clinical decisions rest in part on understanding modifiers of this baseline. Several studies have reported age and sex to influence baseline neurocognitive performance, but few have assessed the potential effect of sleep. We chose to investigate the effect of reported sleep duration on baseline Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT) performance and the number of patient-reported symptoms. We hypothesized that athletes receiving less sleep before baseline testing would perform worse on neurocognitive metrics and report more symptoms. Cross-sectional study; Level of evidence, 3. We retrospectively reviewed 3686 nonconcussed athletes (2371 male, 1315 female; 3305 high school, 381 college) with baseline symptom and ImPACT neurocognitive scores. Patients were stratified into 3 groups based on self-reported sleep duration the night before testing: (1) short, <7 hours; (2) intermediate, 7-9 hours; and (3) long, ≥9 hours. A multivariate analysis of covariance (MANCOVA) with an α level of .05 was used to assess the influence of sleep duration on baseline ImPACT performance. A univariate ANCOVA was performed to investigate the influence of sleep on total self-reported symptoms. When controlling for age and sex as covariates, the MANCOVA revealed significant group differences on ImPACT reaction time, verbal memory, and visual memory scores but not visual-motor (processing) speed scores. An ANCOVA also revealed significant group differences in total reported symptoms. For baseline symptoms and ImPACT scores, subsequent pairwise comparisons revealed these associations to be most significant when comparing the short and intermediate sleep groups. Our results indicate that athletes sleeping fewer than 7 hours before baseline testing perform worse on 3 of 4 ImPACT scores and report more symptoms. Because SRC management and RTP decisions hinge on the comparison with a reliable baseline evaluation, clinicians should consider sleep duration before baseline neurocognitive testing as a potential factor in the assessment of athletes' recovery.

Crew factors in flight operations. Part 4: Sleep and wakefulness in international aircrews

NASA Technical Reports Server (NTRS)

Graeber, R. C.

1986-01-01

Physiological recordings of sleep and wakefulness in operating international (B-747) flight crews were obtained. Crews spent their first layover (48 h) of a trip in a sleep laboratory where standardized EEG, electro-oculograph (EOC), and electromyograph (EMG) sleep recordings were carried out whenever volunteers chose to sleep. During periods of wakefulness they underwent multiple sleep latency tests every 2 h in order to assess daytime drowsiness. The same standardized recordings were carried out at a home-based laboratory before departure. Approximately four crews each participated in flights over 7 to 9 time zones on five routes. All participants were encouraged to use whatever sleep-wake strategies they thought would provide them with the most satisfactory crew rest. Overall, layover sleep quality was not seriously disturbed, but eastward flights produced greater sleep disruption. The contributors of individual factors and the usefulness of various sleep strategies are discussed in the individual laboratory reports and in an operational summary.

Central effects of citral, myrcene and limonene, constituents of essential oil chemotypes from Lippia alba (Mill.) n.e. Brown.

PubMed

do Vale, T Gurgel; Furtado, E Couto; Santos, J G; Viana, G S B

2002-12-01

Citral, myrcene and limonene (100 and 200 mg/kg body wt., i.p.), constituents of essential oils from Lippia alba chemotypes, decreased not only the number of crossings but also numbers for rearing and grooming, as measured by the open-field test in mice. Although muscle relaxation detected by the rota rod test was seen only at the highest doses of citral (200 mg/kg body wt.) and myrcene (100 and 200 mg/kg body wt.), this effect was observed even at the lowest dose of limonene (50 mg/kg body wt.). Also, citral and myrcene (100 and 200 mg/kg body wt.) increased barbiturate sleeping time as compared to control. Limonene was also effective at the highest dose, and although citral did not increase the onset of sleep, it increased the duration of sleep, which is indicative of a potentiation of sleeping time. Citral (100 and 200 mg/kg body wt.) increased 2.3 and 3.5 times, respectively, the barbiturate sleeping time in mice. Similar effects were observed for myrcene and limonene at the highest dose (200 mg/kg body wt.) which increased the sleeping time around 2.6 times. In the elevated-plus maze, no effect was detected with citral up to 25 mg/kg body wt., while at a high dose it decreased by 46% the number of entries in the open arms. A smaller but significant effect was detected with limonene (5 mg/kg body wt.). While myrcene (10 mg/kg body wt.) decreased only by 22% the number of entries in the open arms, this parameter was decreased by 48% at the highest dose. Our study showed that citral, limonene and myrcene presented sedative as well as motor relaxant effects. Although only at the highest dose, they also produced a potentiation of the pentobarbital-induced sleeping time in mice, which was more intense in the presence of citral. In addition, neither of them showed an anxiolytic effect, but rather a slight anxiogenic type of effect at the higher doses.

Older poor-sleeping women display a smaller evening increase in melatonin secretion and lower values of melatonin and core body temperature than good sleepers.

PubMed

Olbrich, Denise; Dittmar, Manuela

2011-10-01

Melatonin concentration and core body temperature (CBT) follow endogenous circadian biological rhythms. In the evening, melatonin level increases and CBT decreases. These changes are involved in the regulation of the sleep-wake cycle. Therefore, the authors hypothesized that age-related changes in these rhythms affect sleep quality in older people. In a cross-sectional study design, 11 older poor-sleeping women (aged 62-72 yrs) and 9 older good-sleeping women (60-82 yrs) were compared with 10 younger good-sleeping women (23-28 yrs). The older groups were matched by age and body mass index. Sleep quality was assessed by the Pittsburgh Sleep Quality Index questionnaire. As an indicator of CBT, oral temperature was measured at 1-h intervals from 17:00 to 24:00 h. At the same time points, saliva samples were collected for determining melatonin levels by enzyme-linked immunosorbent assay (ELISA). The dim light melatonin onset (DLMO), characterizing the onset of melatonin production, was calculated. Evening changes in melatonin and CBT levels were tested by the Friedman test. Group comparisons were performed with independent samples tests. Predictors of sleep-onset latency (SOL) were assessed by regression analysis. Results show that the mean CBT decreased in the evening from 17:00 to 24:00 h in both young women (from 36.57°C to 36.25°C, p < .001) and older women (from 36.58°C to 35.88°C, p < .001), being lowest in the older poor sleepers (p < .05). During the same time period, mean melatonin levels increased in young women (from 16.2 to 54.1 pg/mL, p < .001) and older women (from 10.0 to 23.5 pg/mL, p < .001), being lowest among the older poor sleepers (from 20:00 to 24:00 h, p < .05 vs. young women). Older poor sleepers also showed a smaller increase in melatonin level from 17:00 to 24:00 h than older good sleepers (mean ± SD: 7.0 ± 9.63 pg/mL vs. 15.6 ± 24.1 pg/mL, p = .013). Accordingly, the DLMO occurred at similar times in young (20:10 h) and older (19:57 h) good-sleeping women, but was delayed ∼50 min in older poor-sleeping women (20:47 h). Older poor sleepers showed a shorter phase angle between DLMO and sleep onset, but a longer phase angle between CBT peak and sleep onset than young good sleepers, whereas older good sleepers had intermediate phase angles (insignificant). Regression analysis showed that the DLMO was a significant predictor of SOL in the older women (R(2) = 0.64, p < .001), but not in the younger women. This indicates that melatonin production started later in those older women who needed more time to fall asleep. In conclusion, changes in melatonin level and CBT were intact in older poor sleepers in that evening melatonin increased and CBT decreased. However, poor sleepers showed a weaker evening increase in melatonin level, and their DLMO was delayed compared with good sleepers, suggesting that it is not primarily the absolute level of endogenous melatonin, but rather the timing of the circadian rhythm in evening melatonin secretion that might be related to disturbances in the sleep-wake cycle in older people.

Polysomnographic evaluation of sleep quality and quantitative variables in women as a function of mood, reproductive status, and age

PubMed Central

Orff, Henry J.; Meliska, Charles J.; Lopez, Ana; Martinez, Fernando; Sorenson, Diane; Parry, Barbara L.

2012-01-01

This archival cross-sectional investigation examined the impact of mood, reproductive status (RS), and age on polysomnographic (PSG) measures in women. PSG was performed on 73 normal controls (NC) and 64 depressed patients (DP), in the course of studies in menstruating, pregnant, postpartum, and peri- and postmenopausal women. A two-factor, between-subjects multivariate analysis of variance (MANOVA) was used to test the main effects of reproductive status (RS: menstrual vs pregnant vs postpartum vs menopausal) and diagnosis (NC vs DP), and their interaction, on PSG measures. To further refine the analyses, a two-factor, between subjects MANOVA was used to test the main effects of age (19 to 27 vs 28 to 36 vs 37 to 45 vs 46+ years) and diagnosis on the PSG data. Analyses revealed that in DP women, rapid eye movement (REM) sleep percentage was significantly elevated relative to NC across both RS and age. Significant differences in sleep efficiency, Stage 1%, and REM density were associated with RS; differences in total sleep time, Stage 2 percentage, and Stage 4 percentage were associated with differences in age. Both RS and age were related to differences in sleep latency, Stage 3 percentage, and Delta percentage. Finally, wake after sleep onset time, REM percentage, and REM latency did not vary with respect to RS or age. Overall, this investigation examined three major variables (mood, RS, and age) that are known to impact sleep in women. Of the variables, age appeared to have the greatest impact on PSG sleep measures, reflecting changes occurring across the lifespan. PMID:23393417

Exercise to improve sleep in insomnia: exploration of the bidirectional effects.

PubMed

Baron, Kelly Glazer; Reid, Kathryn J; Zee, Phyllis C

2013-08-15

Exercise improves sleep quality, mood, and quality of life among older adults with insomnia. The purpose of the study was to evaluate the daily bidirectional relationships between exercise and sleep in a sample of women with insomnia. Participants included 11 women (age M = 61.27, SD 4.15) with insomnia who engaged in 30 min of aerobic exercise 3 times per week. Self-reported sleep quality was assessed at baseline and at 16 weeks. Sleep and exercise logs and wrist activity were collected continuously. Sleep variables included subjective sleep quality and objective measures recorded via wrist actigraphy (sleep onset latency [SOL], total sleep time [TST], sleep efficiency [SE], wake after sleep onset [WASO], and fragmentation index [FI]). Age, subjective sleep quality, TST, SOL, and physical fitness at baseline were tested as moderators of the daily effects. TST, SE, and self-reported global sleep quality improved from baseline to 16 weeks (p values < 0.05). Baseline ratings of sleepiness were negatively correlated with exercise session duration (p < 0.05). Daily exercise was not associated with subjective or objective sleep variables during the corresponding night. However, participants had shorter exercise duration following nights with longer SOL (p < 0.05). TST at baseline moderated the daily relationship between TST and next day exercise duration (p < 0.05). The relationship between shorter TST and shorter next day exercise was stronger in participants who had shorter TST at baseline. Results suggest that sleep influences next day exercise rather than exercise influencing sleep. The relationship between TST and next day exercise was stronger for those with shorter TST at baseline. These results suggest that improving sleep may encourage exercise participation.

Continuity and Change in Poor Sleep from Childhood to Early Adolescence

PubMed Central

Pesonen, Anu-Katriina; Martikainen, Silja; Heinonen, Kati; Wehkalampi, Karoliina; Lahti, Jari; Kajantie, Eero; Räikkönen, Katri

2014-01-01

Study Objectives: We examined associations between pubertal maturation and sleep in early adolescence, at age 12 y, and continuity and change in actigraphy-based sleep and parent-reported sleep disorders from age 8 to 12 y. We also explored longitudinal associations between actigraph estimates of sleep and sleep disorders. Design: A cohort study of children born in 1998 and tested at ages 8 y (standard deviation [SD] = 0.3) and 12 y (SD = 0.5). Participants: A total of 348 children participated in cross-sectional analyses. We had longitudinal actigraphy data for 188 children and repeated parent reports of sleep disorders for 229 children. Measurements and Results: At age 8 y, participants wore actigraphs for 7.1 nights (SD = 1.2, range 3-14) on average and at age 12 y for 8.4 nights (SD = 1.7, range 3-11). Sleep disorders were parent-rated based on the Sleep Disturbance Scale for Children. Pubertal maturity was self-reported at age 12 y using the continuous Pubertal Development Scale and the picture-assisted categorical Tanner scales. Results: Significant mean-level changes toward shorter but higher quality sleep occurred over time. Sleep variables had low to high rank-order stability over time. Sleep disorders were highly stable from age 8 to 12 y. Actigraphy-based sleep and parent-rated sleep disorders showed no association either in cross-section or longitudinally. Pubertal maturation was not associated with worse sleep. Conclusions: Sleep in early adolescence can be anticipated from childhood sleep patterns and disorders, but is not associated with pubertal maturity. Although sleep duration becomes shorter, sleep quality may improve during early adolescence. Parent-rated sleep disorders are distinct from actigraph estimates of sleep. Citation: Pesonen AK; Martikainen S; Heinonen K; Wehkalampi K; Lahti J; Kajantie E; Räikkönen K. Continuity and change in poor sleep from childhood to early adolescence. SLEEP 2014;37(2):289-297. PMID:24497657

Sleep, attention, and executive functioning in children with attention-deficit/hyperactivity disorder.

PubMed

Moreau, Vincent; Rouleau, Nancie; Morin, Charles M

2013-11-01

The objective of this study was to investigate potential relationships between two measures of sleep impairments (i.e., sleep duration and sleep efficiency [SE]) and attention and executive functioning in children with attention-deficit/hyperactivity disorder (ADHD). Parents of 43 children (mean age = 10 ± 1.8 years) with ADHD completed sleep and behavioral questionnaires. Children also wore a wrist actigraph for seven nights and were subsequently assessed with the Conners' continuous performance test (CPT)-2. A significant relationship was found between lower SE and increased variability in reaction time on the CPT. Shorter sleep duration was associated with a range of executive functioning problems as reported by the parents. The relationships between sleep duration and the executive functioning measures held even after controlling for age, gender, and use of medication, but not the relationships with SE. These results suggest that sleep quantity is an important correlate of executive functioning in children with ADHD.

Could parental rules play a role in the association between short sleep and obesity in young children?

PubMed

Jones, Caroline H D; Pollard, Tessa M; Summerbell, Carolyn D; Ball, Helen

2014-05-01

Short sleep duration is associated with obesity in young children. This study develops the hypothesis that parental rules play a role in this association. Participants were 3-year-old children and their parents, recruited at nursery schools in socioeconomically deprived and non-deprived areas of a North-East England town. Parents were interviewed to assess their use of sleep, television-viewing and dietary rules, and given diaries to document their child's sleep for 4 days/5 nights. Children were measured for height, weight, waist circumference and triceps and subscapular skinfold thicknesses. One-hundred and eight families participated (84 with complete sleep data and 96 with complete body composition data). Parental rules were significantly associated together, were associated with longer night-time sleep and were more prevalent in the non-deprived-area compared with the deprived-area group. Television-viewing and dietary rules were associated with leaner body composition. Parental rules may in part confound the association between night-time sleep duration and obesity in young children, as rules cluster together across behavioural domains and are associated with both sleep duration and body composition. This hypothesis should be tested rigorously in large representative samples.

Sleep, but not other daily routines, mediates the association between maternal employment and BMI for preschool children.

PubMed

Speirs, Katherine E; Liechty, Janet M; Wu, Chi-Fang

2014-12-01

It has been established that the more time mothers spend working outside of the home, the more likely their preschool-aged children are to be overweight. However, the mechanisms explaining this relationship are not well understood. Our objective was to explore child sleep, dietary habits, TV time, and family mealtime routines as mediators of the relationship between maternal employment status (full-time, part-time, and no or minimal employment) and child body mass index (BMI) percentile. Data were drawn from waves 1 and 2 of STRONG Kids, a prospective panel study examining childhood obesity among parent-preschooler dyads (n = 247). Mothers reported their own work hours, their child's hours of nighttime sleep, dietary habits, TV time, and mealtime routines. Trained staff measured child height and weight. Compared to working 0-19 h/week, both full-time (>35 h/week) and part-time (20-34 h/week) employment predicted higher child BMI percentile 1 year later. Hours of child nighttime sleep partially mediated the association between maternal full-time employment and child BMI percentile. Adjusting for individual and family characteristics, children whose mothers were employed full time were less likely to sleep longer hours than children whose mothers were employed 0-19 h/week (b = -0.49, p < 0.04). Shorter child nighttime sleep was associated with higher BMI percentile (b = -7.31, p < 0.001). None of the other mediation pathways tested were significant. These findings add to the growing literature on the importance of adequate sleep for young children's health. Copyright © 2014 Elsevier B.V. All rights reserved.

PC-PVT 2.0: An updated platform for psychomotor vigilance task testing, analysis, prediction, and visualization.

PubMed

Reifman, Jaques; Kumar, Kamal; Khitrov, Maxim Y; Liu, Jianbo; Ramakrishnan, Sridhar

2018-07-01

The psychomotor vigilance task (PVT) has been widely used to assess the effects of sleep deprivation on human neurobehavioral performance. To facilitate research in this field, we previously developed the PC-PVT, a freely available software system analogous to the "gold-standard" PVT-192 that, in addition to allowing for simple visual reaction time (RT) tests, also allows for near real-time PVT analysis, prediction, and visualization in a personal computer (PC). Here we present the PC-PVT 2.0 for Windows 10 operating system, which has the capability to couple PVT tests of a study protocol with the study's sleep/wake and caffeine schedules, and make real-time individualized predictions of PVT performance for such schedules. We characterized the accuracy and precision of the software in measuring RT, using 44 distinct combinations of PC hardware system configurations. We found that 15 system configurations measured RTs with an average delay of less than 10 ms, an error comparable to that of the PVT-192. To achieve such small delays, the system configuration should always use a gaming mouse as the means to respond to visual stimuli. We recommend using a discrete graphical processing unit for desktop PCs and an external monitor for laptop PCs. This update integrates a study's sleep/wake and caffeine schedules with the testing software, facilitating testing and outcome visualization, and provides near-real-time individualized PVT predictions for any sleep-loss condition considering caffeine effects. The software, with its enhanced PVT analysis, visualization, and prediction capabilities, can be freely downloaded from https://pcpvt.bhsai.org. Published by Elsevier B.V.

Enhancing Slow Wave Sleep with Sodium Oxybate Reduces the Behavioral and Physiological Impact of Sleep Loss

PubMed Central

Walsh, James K.; Hall-Porter, Janine M.; Griffin, Kara S.; Dodson, Ehren R.; Forst, Elizabeth H.; Curry, Denise T.; Eisenstein, Rhody D.; Schweitzer, Paula K.

2010-01-01

Study Objectives: To investigate whether enhancement of slow wave sleep (SWS) with sodium oxybate reduces the impact of sleep deprivation. Design: Double-blind, parallel group, placebo-controlled design Setting: Sleep research laboratory Participants: Fifty-eight healthy adults (28 placebo, 30 sodium oxybate), ages 18-50 years. Interventions: A 5-day protocol included 2 screening/baseline nights and days, 2 sleep deprivation nights, each followed by a 3-h daytime (08:00-11:00) sleep opportunity and a recovery night. Sodium oxybate or placebo was administered prior to each daytime sleep period. Multiple sleep latency test (MSLT), psychomotor vigilance test (PVT), Karolinska Sleepiness Scale (KSS), and Profile of Mood States were administered during waking hours. Measurements and Results: During daytime sleep, the sodium oxybate group had more SWS, more EEG spectral power in the 1-9 Hz range, and less REM. Mean MSLT latency was longer for the sodium oxybate group on the night following the first daytime sleep period and on the day following the second day sleep period. Median PVT reaction time was faster in the sodium oxybate group following the second day sleep period. The change from baseline in SWS was positively correlated with the change in MSLT and KSS. During recovery sleep the sodium oxybate group had less TST, SWS, REM, and slow wave activity (SWA) than the placebo group. Conclusions: Pharmacological enhancement of SWS with sodium oxybate resulted in a reduced response to sleep loss on measures of alertness and attention. In addition, SWS enhancement during sleep restriction appears to result in a reduced homeostatic response to sleep loss. Citation: Walsh JK; Hall-Porter JM; Griffin KS; Dodson ER; Forst EH; Curry DT; Eisenstein RD; Schweitzer PK. Enhancing slow wave sleep with sodium oxybate reduces the behavioral and physiological impact of sleep loss. SLEEP 2010;33(9):1217-1225. PMID:20857869

Mild Traumatic Brain Injury Chronically Impairs Sleep- and Wake-Dependent Emotional Processing.

PubMed

Mantua, Janna; Henry, Owen S; Garskovas, Nolan F; Spencer, Rebecca M C

2017-06-01

A single traumatic brain injury (TBI), even when mild (ie, concussion), can cause lasting consequences. Individuals with a history of chronic (>1-year prior) mild TBI have an increased risk of mood disturbances (eg, depression, suicide). This population also has lingering sleep alterations, including poor sleep quality and changes in sleep stage proportions. Given these sleep deficits, we aimed to test whether sleep-dependent emotional memory consolidation is reduced in this population. We utilized a mild TBI group (3.7 ± 2.9 years post injury) and an uninjured (non-TBI) population. Participants viewed negative and neutral images both before and after a 12-hour period containing sleep ("Sleep" group) or an equivalent period of time spent awake ("Wake" group). Participants rated images for valence/arousal at both sessions, and memory recognition was tested at session two. The TBI group had less rapid eye movement (REM), longer REM latency, and more sleep complaints. Sleep-dependent memory consolidation of nonemotional images was present in all participants. However, consolidation of negative images was only present in the non-TBI group. A lack of differentiation between the TBI Sleep and Wake groups was due to poor performance in the sleep group and, unexpectedly, enhanced performance in the wake group. Additionally, although the non-TBI participants habituated to negative images over a waking period, the TBI participants did not. We propose disrupted sleep- and wake-dependent emotional processing contributes to poor emotional outcomes following chronic, mild TBI. This work has broad implications, as roughly one-third of the US population will sustain a mild TBI during their lifetime. © Sleep Research Society 2017. Published by Oxford University Press on behalf of the Sleep Research Society. All rights reserved. For permissions, please e-mail journals.permissions@oup.com.

The effects of napping on cognitive function in preschoolers.

PubMed

Lam, Janet C; Mahone, E Mark; Mason, Thornton; Scharf, Steven M

2011-01-01

To determine the relationship between napping and cognitive function in preschool-aged children. Daytime napping, nighttime sleep, and cognitive function were assessed in 59 typically developing children aged 3 to 5 years, who were enrolled in full-time childcare. Participants wore an actigraphy watch for 7 days to measure sleep and napping patterns and completed neuropsychological testing emphasizing attention, response control, and vocabulary. Parents of participants completed behavior ratings and sleep logs during the study. Sleep/wake cycles were scored with the Sadeh algorithm. Children who napped more on weekdays were also more likely to nap during weekends. Weekday napping and nighttime sleep were inversely correlated, such that those who napped more slept less at night, although total weekday sleep remained relatively constant. Weekday napping was significantly (negatively) correlated with vocabulary and auditory attention span, and weekday nighttime sleep was positively correlated with vocabulary. Nighttime sleep was also significantly negatively correlated with performance, such that those who slept less at night made more impulsive errors on a computerized go/no-go test. Daytime napping is actually negatively correlated with neurocognitive function in preschoolers. Nighttime sleep seems to be more critical for development of cognitive performance. Cessation of napping may serve as a developmental milestone of brain maturation. Children who nap less do not appear to be sleep deprived, especially if they compensate with increased nighttime sleep. An alternative explanation is that children who sleep less at night are sleep deprived and require a nap. A randomized trial of nap restriction would be the next step in understanding the relationship between napping and neurocognitive performance.

The Effects of Napping on Cognitive Function in Preschoolers

PubMed Central

Lam, Janet C.; Mahone, E. Mark; Mason, Thornton B.A.; Scharf, Steven M.

2011-01-01

Objective To determine the relationship between napping and cognitive function in preschool-aged children. Methods Daytime napping, nighttime sleep and cognitive function were assessed in fifty-nine typically developing children ages 3-5 years, who were enrolled in full-time childcare. Participants wore an actigraphy watch for 7 days to measure sleep and napping patterns, and completed neuropsychological testing emphasizing attention, response control, and vocabulary. Parents of participants completed behavior ratings and sleep logs during the study. Sleep/wake cycles were scored with the Sadeh algorithm. Results Children who napped more on weekdays were also more likely to nap during weekends. Weekday napping and nighttime sleep were inversely correlated, such that those who napped more slept less at night, while total weekday sleep remained relatively constant. Weekday napping was significantly (negatively) correlated with vocabulary and auditory attention span, and weekday nighttime sleep was positively correlated with vocabulary. Nighttime sleep was also significantly negatively correlated with performance, such that those who slept less at night made more impulsive errors on a computerized go/no-go test. Conclusions Daytime napping is actually negatively correlated with neurocognitive function in preschoolers. Nighttime sleep appears to be more critical for development of cognitive performance. Cessation of napping may serve as a developmental milestone of brain maturation. Children who nap less do not appear to be sleep deprived, especially if they compensate with increased nighttime sleep. An alternative explanation is that children who sleep less at night are sleep deprived and require a nap. A randomized trial of nap restriction would be the next step in understanding the relationship between napping and neurocognitive performance. PMID:21217402

Randomised controlled trial of the effectiveness of using foot reflexology to improve quality of sleep amongst Taiwanese postpartum women.

PubMed

Li, Chia-Yen; Chen, Su-Chiu; Li, Chung-Yi; Gau, Meei-Ling; Huang, Chiu-Mieh

2011-04-01

to examine the effectiveness of using foot reflexology to improve sleep quality in postpartum women. randomised controlled trial, conducted at two postpartum centres in northern Taiwan. 65 postpartum women reporting poor quality of sleep were recruited from July 2007 to December 2007. participants were assigned randomly to either an intervention or a control group. Participants in both groups received the same care except for reflexology therapy. The intervention group received a single 30-minute foot reflexology session at the same time each evening for five consecutive days. Sessions were administered by a certified nurse reflexologist. MEASURES AND FINDINGS: the outcome measure was the Pittsburgh sleep quality index (PSQI), and this was performed at baseline and post test. Mean PQSI scores for both groups declined over time between baseline and post test. Using a generalised estimation equation to control several confounding variables, the changes in mean PSQI were found to be significantly lower in the intervention group (β=-2.24, standard error=0.38, p<0.001) than in the control group. an intervention involving foot reflexology in the postnatal period significantly improved the quality of sleep. midwives should evaluate maternal sleep quality and design early intervention programmes to improve quality of sleep in order to increase maternal biopsychosocial well-being. Midwives interested in complementary therapies should be encouraged to obtain training in reflexology and to apply it in clinical settings if it is allowed. Copyright © 2009 Elsevier Ltd. All rights reserved.

Effects of Slow-Stroke Back Massage on Symptom Cluster in Adult Patients With Acute Leukemia: Supportive Care in Cancer Nursing.

PubMed

Miladinia, Mojtaba; Baraz, Shahram; Shariati, Abdolali; Malehi, Amal Saki

Patients with acute leukemia usually experience pain, fatigue, and sleep disorders, which affect their quality of life. Massage therapy, as a nondrug approach, can be useful in controlling such problems. However, very few studies have been conducted on the effects of massage therapy on the complications of leukemia. The aim of this study was to examine the effects of slow-stroke back massage (SSBM) on the symptom cluster in acute leukemia adult patients undergoing chemotherapy. In this randomized controlled trial, 60 patients with acute leukemia were allocated randomly to either the intervention or control group. The intervention group received SSBM 3 times a week (every other day for 10 minutes) for 4 weeks. The pain, fatigue, and sleep disorder intensities were measured using the numeric rating scale. The sleep quality was measured using the Pittsburgh Sleep Quality Index. Statistical tests of χ, t test, and the repeated-measure analysis of variance were used for data analysis. Results showed that the SSBM intervention significantly reduced the progressive sleep disorder, pain, fatigue, and improved sleep quality over time. Slow-stroke back massage, as a simple, noninvasive, and cost-effective approach, along with routine nursing care, can be used to improve the symptom cluster of pain, fatigue, and sleep disorders in leukemia patients. Oncology nurses can increase their knowledge regarding this symptom cluster and work to diminish the cluster components by using SSBM in adult leukemia patients.

Circadian Entrainment, Sleep-Wake Regulation and Neurobehavioral Performance During Extended Duration Space Flight

NASA Technical Reports Server (NTRS)

Czeisler, Charles A.

1999-01-01

Long-duration manned space flight requires crew members to maintain a high level of cognitive performance and vigilance while operating and monitoring sophisticated instrumentation. However, the reduction in the strength of environmental synchronizers in the space environment leads to misalignment of circadian phase among crew members, coupled with restricted time available to sleep, results in sleep deprivation and consequent deterioration of neurobehavioral function. Crew members are provided, and presently use, long-acting benzodiazepine hypnotics on board the current, relatively brief space shuttle missions to counteract such sleep disruption, a situation that is only likely to worsen during extended duration missions. Given the known carry-over effects of such compounds on daytime performance, together with the reduction in emergency readiness associated with their use at night, NASA has recognized the need to develop effective but safe countermeasures to allow crew members to obtain an adequate amount of sleep. Over the past eight years, we have successfully implemented a new technology for shuttle crew members involving bright light exposure during the pre-launch period to facilitate adaptation of the circadian timing system to the inversions of the sleep-wake schedule often required during dual shift missions. However for long duration space station missions it will be necessary to develop effective and attainable countermeasures that can be used chronically to optimize circadian entrainment. Our current research effort is to study the effects of light-dark cycles with reduced zeitgeber strength, such as are anticipated during long-duration space flight, on the entrainment of the endogenous circadian timing system and to study the effects of a countermeasure that consists of scheduled brief exposures to bright light on the human circadian timing system. The proposed studies are designed to address the following Specific Aims: (1) test the hypothesis that synchronization of the human circadian pacemaker will be disturbed in men and women by the reduction in LD cycle strength. (2) test the hypothesis that this disturbed circadian synchronization will result in the secretion of the sleep-promoting hormone melatonin during the waking day, disturbed sleep, reduced growth hormone secretion, and impaired performance and daytime alertness; (3) as a countermeasure, test the hypothesis that brief daily exposures to bright light (10,000 lux) will reestablish normal entrained circadian phase, resulting in improved sleep consolidation, normalized sleep structure and endogenous growth hormone secretion and enhanced daytime performance. To date, we have carried out twelve experiments to address Hypotheses I and 2 and data analyses are in progress. The results of the current research may have important implications for the treatment of circadian rhythm sleep disorders, such as delayed sleep phase syndrome and shift-work dyssomnia, which are anticipated to have a high incidence and prevalence during extended duration space flight such as planned for the International Space Station and manned missions to Mars.

Influence of sleep and meal schedules on performance peaks in competitive sprinters.

PubMed

Javierre, C; Calvo, M; Díez, A; Garrido, E; Segura, R; Ventura, J L

1996-08-01

The influence of sleep and meal schedules on performance in short distance running was assessed in a group of 8 national-class competition male sprinters. They were tested on Saturdays for five consecutive weeks. On each testing day, the performance time for an 80 m sprint was registered on eight different occasions during days 1 and 4, on 9 occasions on days 2 and 5, and on 7 occasions on day 3. On control days (days 1 and 4) performance gradually improved during the morning up to 13:00 h, decreased at 15:00 h, and again improved thereafter, with a maximum peak performance at 19:00 h. On day 2, in which sleep/wake cycles and meal-times were advanced for two hours, and on day 3, in which timetables were delayed for two hours, maximum peak performance was observed at 17:00 h and 21:00 h, respectively. At the time of maximum peak performance on both days a statistically significant improvement was observed as compared with the control day (day 2, p < 0.01; day 3, p = 0.001). On day 5, in which only the sleep/wake cycle was advanced for two hours, performance in the afternoon and evening was similar to that recorded on days 1 and 4. We observed that easy manipulation of sleep and meal schedules would allow competitive sprinters to synchronize peak power output with the time of the athletic event, increasing the chances for improvement in performance.

Does hormone therapy affect attention and memory in sleep-deprived women?

PubMed

Alhola, P; Kylmälä, M; Urrila, A Sofia; Karakorpi, M; Portin, R; Kalleinen, N; Polo-Kantola, P

2008-06-01

To evaluate whether hormone therapy (HT) modifies cognitive performance during sleep deprivation in postmenopausal women. Comparison was made with a group of young women. Participants included 26 postmenopausal women (age 58-72 years, 16 HT users, 10 non-users), 11 young women (age 20-26 years). They spent four consecutive nights in the sleep laboratory. Cognitive tests of attention, working memory, and verbal episodic memory were carried out after the baseline night, 25-h sleep deprivation, and recovery night. Sleep deprivation impaired performance in all groups. It was manifested either as delayed practice effect or deteriorated performance (p < 0.05). In simple reaction time and 10-choice reaction time, non-users and young maintained their performance, whereas HT users suffered a minor impairment (p < 0.01). In other measurements, there was no interaction of group and condition. In 10-choice reaction time and vigilance, postmenopausal women made fewer errors and omissions than the young (p < 0.05). For most tasks, all groups showed improvement after one recovery night. HT had a minor adverse effect on cognitive performance during sleep deprivation. Attention and memory deteriorated similarly in postmenopausal and young women, despite the lower initial performance level of postmenopausal women. One night of sleep ensured recovery in most tasks.

Sleep Eduction: Treatment & Therapy

MedlinePlus

... Overview & Facts Symptoms & Causes Diagnosis & Self Tests Treatment Sleep Apnea Overview & Facts Symptoms & Risk Factors Self-Tests Diagnosis ... for a Sleep Study Testing Process & Results Home Sleep Apnea Testing Overview Testing Process & Results CPAP Overview Benefits ...

Mexican American Adolescents’ Sleep Patterns: Contextual Correlates and Implications for Health and Adjustment in Young Adulthood

PubMed Central

Kuo, Sally I-Chun; Updegraff, Kimberly A.; Zeiders, Katharine H.; McHale, Susan M.; Umaña-Taylor, Adriana J.; De Jesús, Sue A. Rodríguez

2014-01-01

Late adolescence is a period of substantial risk for unhealthy sleep patterns. This study investigated the contextual correlates and health and adjustment implications of sleep patterns among Mexican American youth (N = 246; 51% female). We focused on Mexican American youth because they represent a large and rapidly increasing subgroup of the U.S. population that is at higher risk for health and adjustment problems; this higher risk may be explained, in part, by sleep patterns. Using data from 7 phone diary interviews conducted when youth averaged 18 years of age, we assessed average nighttime sleep duration and night-to-night variability in sleep duration. Guided by socio-ecological models, we first examined how experiences in the family context (time spent and quality of relationships with parents, parents’ familism values) and in extra-familial contexts (school, work, peers) were related to sleep duration and variability. The findings revealed that time spent in school, work, and with peers linked to less sleep. Further, conflict with mothers was related to greater sleep variability. Next, we tested the implications of sleep in late adolescence for health (perceived physical health, body mass index) and adjustment (depressive symptoms, risky behaviors) in young adulthood. These findings indicated that more sleep variability predicted relative decreases in health and increases in risky behaviors, and shorter sleep duration predicted relative decreases in poorer perceived health for males. The discussion highlights the significance of the transition to young adulthood as a target for sleep research and the importance of studying sleep within its socio-cultural context. PMID:25047598

Sleep supports cued fear extinction memory consolidation independent of circadian phase.

PubMed

Melo, Irene; Ehrlich, Ingrid

2016-07-01

Sleep promotes memory, particularly for declarative learning. However, its role in non-declarative, emotional memories is less well understood. Some studies suggest that sleep may influence fear-related memories, and thus may be an important factor determining the outcome of treatments for emotional disorders such as post-traumatic stress disorder. Here, we investigated the effect of sleep deprivation and time of day on fear extinction memory consolidation. Mice were subjected to a cued Pavlovian fear and extinction paradigm at the beginning of their resting or active phase. Immediate post-extinction learning sleep deprivation for 5h compromised extinction memory when tested 24h after learning. Context-dependent extinction memory recall was completely prevented by sleep-manipulation during the resting phase, while impairment was milder during the active phase and extinction memory retained its context-specificity. Importantly, control experiments excluded confounding factors such as differences in baseline locomotion, fear generalization and stress hormone levels. Together, our findings indicate that post-learning sleep supports cued fear extinction memory consolidation in both circadian phases. The lack of correlation between memory efficacy and sleep time suggests that extinction memory may be influenced by specific sleep events in the early consolidation period. Copyright © 2016 Elsevier Inc. All rights reserved.

The Circadian System Contributes to Apnea Lengthening across the Night in Obstructive Sleep Apnea.

PubMed

Butler, Matthew P; Smales, Carolina; Wu, Huijuan; Hussain, Mohammad V; Mohamed, Yusef A; Morimoto, Miki; Shea, Steven A

2015-11-01

To test the hypothesis that respiratory event duration exhibits an endogenous circadian rhythm. Within-subject and between-subjects. Inpatient intensive physiologic monitoring unit at the Brigham and Women's Hospital. Seven subjects with moderate/severe sleep apnea and four controls, age 48 (SD = 12) years, 7 males. Subjects completed a 5-day inpatient protocol in dim light. Polysomnography was recorded during an initial control 8-h night scheduled at the usual sleep time, then through 10 recurrent cycles of 2 h 40 min sleep and 2 h 40 min wake evenly distributed across all circadian phases, and finally during another 8-h control sleep period. Event durations, desaturations, and apnea-hypopnea index for each sleep opportunity were assessed according to circadian phase (derived from salivary melatonin), time into sleep, and sleep stage. Average respiratory event durations in NREM sleep significantly lengthened across both control nights (21.9 to 28.2 sec and 23.7 to 30.2 sec, respectively). During the circadian protocol, event duration in NREM increased across the circadian phases that corresponded to the usual sleep period, accounting for > 50% of the increase across normal 8-h control nights. AHI and desaturations were also rhythmic: AHI was highest in the biological day while desaturations were greatest in the biological night. The endogenous circadian system plays an important role in the prolongation of respiratory events across the night, and might provide a novel therapeutic target for modulating sleep apnea. © 2015 Associated Professional Sleep Societies, LLC.

Interictal spiking increases with sleep depth in temporal lobe epilepsy.

PubMed

Malow, B A; Lin, X; Kushwaha, R; Aldrich, M S

1998-12-01

To test the hypothesis that deepening sleep activates focal interictal epileptiform discharges (IEDs), we performed EEG-polysomnography in 21 subjects with medically refractory temporal lobe epilepsy. At the time of study, subjects were seizure-free for > or =24 h and were taking stable doses of antiepileptic medications (AEDs). Sleep depth was measured by log delta power (LDP). Visual sleep scoring and visual detection of IEDs also were performed. Logistic-regression analyses of IED occurrence in relation to LDP were carried out for two groups of subjects, nine with frequent IEDs (group 1) and 12 with rare IEDs (group 2). The LDP differentiated visually scored non-rapid eye movement (NREM) sleep stages (p = 0.0001). The IEDs were most frequent in NREM stages 3/4 and least frequent in REM sleep. Within NREM sleep, in both groups, IEDs were more frequent at higher levels of LDP (p < 0.05). In group 1, after accounting for the level of LDP, IEDs were more frequent (a) on the ascending limb of LDP and with more rapid increases in LDP (p = 0.007), (b) in NREM than in REM sleep (p = 0.002), and (c) closer to sleep onset (p < 0.0001). Fewer than 1% of IEDs occurred within 10 s of an EEG arousal. Processes underlying the deepening of NREM sleep, including progressive hyperpolarization in thalamocortical projection neurons, may contribute to IED activation in partial epilepsy. Time from sleep onset and NREM versus REM sleep also influence IED occurrence.

Effects of afternoon "siesta" naps on sleep, alertness, performance, and circadian rhythms in the elderly

NASA Technical Reports Server (NTRS)

Monk, T. H.; Buysse, D. J.; Carrier, J.; Billy, B. D.; Rose, L. R.

2001-01-01

STUDY OBJECTIVES: To determine the effects of a 90-minute afternoon nap regimen on nocturnal sleep, circadian rhythms, and evening alertness and performance levels in the healthy elderly. DESIGN AND SETTING: Nine healthy elderly subjects (4m, 5f, age range 74y-87y) each experienced both nap and no-nap conditions in two studies each lasting 17 days (14 at home, 3 in the laboratory). In the nap condition a 90-minute nap was enforced between 13:30 and 15:00 every day, in the no-nap condition daytime napping was prohibited, and activity encouraged in the 13:30-15:00 interval. The order of the two conditions was counterbalanced. PARTICIPANTS: N/A INTERVENTIONS: N/A MEASUREMENTS: Diary measures, pencil and paper alertness tests, and wrist actigraphy were used at home. In the 72 hour laboratory studies, these measures were augmented by polysomnographic sleep recording, continuous rectal temperature measurement, a daily evening single trial of a Multiple Sleep Latency Test (MSLT), and computerized tests of mood, activation and performance efficiency. RESULTS: By the second week in the "at home" study, an average of 58 minutes of sleep was reported per siesta nap; in the laboratory, polysomnography confirmed an average of 57 minutes of sleep per nap. When nap and no-nap conditions were compared, mixed effects on nocturnal sleep were observed. Diary measures indicated no significant difference in nocturnal sleep duration, but a significant increase (of 38 mins.) in 24-hour Total Sleep Time (TST) when nocturnal sleeps and naps were added together (p<0.025). The laboratory study revealed a decrease of 2.4% in nocturnal sleep efficiency in the nap condition (p<0.025), a reduction of nocturnal Total Sleep Time (TST) by 48 mins. in the nap condition (p<0.001) which resulted primarily from significantly earlier waketimes (p<0.005), but no reliable effects on Wake After Sleep Onset (WASO), delta sleep measures, or percent stages 1 & 2. Unlike the diary study, the laboratory study yielded no overall increase in 24-hour TST consequent upon the siesta nap regimen. The only measure of evening alertness or performance to show an improvement was sleep latency in a single-trial evening MSLT (nap: 15.6 mins., no nap: 11.5 mins., p<0.005). No significant change in circadian rhythm parameters was observed. CONCLUSIONS: Healthy seniors were able to adopt a napping regimen involving a 90-minute siesta nap each day between 13:30 and 15:00, achieving about one hour of actual sleep per nap. There were some negative consequences for nocturnal sleep in terms of reduced sleep efficiency and earlier waketimes, but also some positive consequences for objective evening performance and (in the diary study) 24-hour sleep totals. Subjective alertness measures and performance measures showed no reliable effects and circadian phase parameters appeared unchanged.

Polymorphisms in the circadian expressed genes PER3 and ARNTL2 are associated with diurnal preference and GNβ3 with sleep measures

PubMed Central

Parsons, Michael J; Lester, Kathryn J; Barclay, Nicola L; Archer, Simon N; Nolan, Patrick M; Eley, Thalia C; Gregory, Alice M

2014-01-01

Sleep and circadian rhythms are intrinsically linked, with several sleep traits, including sleep timing and duration, influenced by both sleep homeostasis and the circadian phase. Genetic variation in several circadian genes has been associated with diurnal preference (preference in timing of sleep), although there has been limited research on whether they are associated with other sleep measurements. We investigated whether these genetic variations were associated with diurnal preference (Morningness–Eveningness Questionnaire) and various sleep measures, including: the global Pittsburgh Sleep Quality index score; sleep duration; and sleep latency and sleep quality. We genotyped 10 polymorphisms in genes with circadian expression in participants from the G1219 sample (n = 966), a British longitudinal population sample of young adults. We conducted linear regressions using dominant, additive and recessive models of inheritance to test for associations between these polymorphisms and the sleep measures. We found a significant association between diurnal preference and a polymorphism in period homologue 3 (PER3) (P < 0.005, recessive model) and a novel nominally significant association between diurnal preference and a polymorphism in aryl hydrocarbon receptor nuclear translocator-like 2 (ARNTL2) (P < 0.05, additive model). We found that a polymorphism in guanine nucleotide binding protein beta 3 (GNβ3) was associated significantly with global sleep quality (P < 0.005, recessive model), and that a rare polymorphism in period homologue 2 (PER2) was associated significantly with both sleep duration and quality (P < 0.0005, recessive model). These findings suggest that genes with circadian expression may play a role in regulating both the circadian clock and sleep homeostasis, and highlight the importance of further studies aimed at dissecting the specific roles that circadian genes play in these two interrelated but unique behaviours. PMID:24635757

Acute administration of fluoxetine normalizes rapid eye movement sleep abnormality, but not depressive behaviors in olfactory bulbectomized rats.

PubMed

Wang, Yi-Qun; Tu, Zhi-Cai; Xu, Xing-Yuan; Li, Rui; Qu, Wei-Min; Urade, Yoshihiro; Huang, Zhi-Li

2012-01-01

In humans, depression is associated with altered rapid eye movement (REM) sleep. However, the exact nature of the relationship between depressive behaviors and sleep abnormalities is debated. In this study, bilateral olfactory bulbectomy (OBX) was carried out to create a model of depression in rats. The sleep-wake profiles were assayed using a cutting-edge sleep bioassay system, and depressive behaviors were evaluated by open field and forced swimming tests. The monoamine content and monoamine metabolite levels in the brain were determined by a HPLC-electrochemical detection system. OBX rats exhibited a significant increase in REM sleep, especially between 15:00 and 18:00 hours during the light period. Acute treatment with fluoxetine (10 mg/kg, i.p.) immediately abolished the OBX-induced increase in REM sleep, but hyperactivity in the open field test and the time spent immobile in the forced swimming test remained unchanged. Neurochemistry studies revealed that acute administration of fluoxetine increased serotonin (5-HT) levels in the hippocampus, thalamus, and midbrain and decreased levels of the 5-HT metabolite 5-hydroxyindoleacetic acid (5-HIAA). The ratio of 5-HIAA to 5-HT decreased in almost all regions of the brain. These results indicate that acute administration of fluoxetine can reduce the increase in REM sleep but does not change the depressive behaviors in OBX rats, suggesting that there was no causality between REM sleep abnormalities and depressive behaviors in OBX rats. © 2011 The Authors. Journal of Neurochemistry © 2011 International Society for Neurochemistry.

Developing measures of fatigue using an alcohol comparison to validate the effects of fatigue on performance.

PubMed

Williamson, A M; Feyer, A M; Mattick, R P; Friswell, R; Finlay-Brown, S

2001-05-01

The effects of 28 h of sleep deprivation were compared with varying doses of alcohol up to 0.1% blood alcohol concentration (BAC) in the same subjects. The study was conducted in the laboratory. Twenty long-haul truck drivers and 19 people not employed as professional drivers acted as subjects. Tests were selected that were likely to be affected by fatigue, including simple reaction time, unstable tracking, dual task, Mackworth clock vigilance test, symbol digit coding, visual search, sequential spatial memory and logical reasoning. While performance effects were seen due to alcohol for all tests, sleep deprivation affected performance on most tests, but had no effect on performance on the visual search and logical reasoning tests. Some tests showed evidence of a circadian rhythm effect on performance, in particular, simple reaction time, dual task, Mackworth clock vigilance, and symbol digit coding, but only for response speed and not response accuracy. Drivers were slower but more accurate than controls on the symbol digit test, suggesting that they took a more conservative approach to performance of this test. This study demonstrated which tests are most sensitive to sleep deprivation and fatigue. The study therefore has established a set of tests that can be used in evaluations of fatigue and fatigue countermeasures.

Find a Sleep Center Near You

MedlinePlus

... Overview & Facts Symptoms & Causes Diagnosis & Self Tests Treatment Sleep Apnea Overview & Facts Symptoms & Risk Factors Self-Tests Diagnosis ... for a Sleep Study Testing Process & Results Home Sleep Apnea Testing Overview Testing Process & Results CPAP Overview Benefits ...

Adolescents' sleep in low-stress and high-stress (exam) times: a prospective quasi-experiment.

PubMed

Dewald, Julia F; Meijer, Anne Marie; Oort, Frans J; Kerkhof, Gerard A; Bögels, Susan M

2014-01-01

This prospective quasi-experiment (N = 175; mean age = 15.14 years) investigates changes in adolescents' sleep from low-stress (regular school week) to high-stress times (exam week), and examines the (moderating) role of chronic sleep reduction, baseline stress, and gender. Sleep was monitored over three consecutive weeks using actigraphy. Adolescents' sleep was more fragmented during the high-stress time than during the low-stress time, meaning that individuals slept more restless during stressful times. However, sleep efficiency, total sleep time, and sleep onset latency remained stable throughout the three consecutive weeks. High chronic sleep reduction was related to later bedtimes, later sleep start times, later sleep end times, later getting up times, and more time spent in bed. Furthermore, low chronic sleep reduction and high baseline stress levels were related to more fragmented sleep during stressful times. This study shows that stressful times can have negative effects on adolescents' sleep fragmentation, especially for adolescents with low chronic sleep reduction or high baseline stress levels.

The effect of split sleep schedules (6h-on/6h-off) on neurobehavioural performance, sleep and sleepiness.

PubMed

Short, Michelle A; Centofanti, Stephanie; Hilditch, Cassie; Banks, Siobhan; Lushington, Kurt; Dorrian, Jillian

2016-05-01

Shorter, more frequent rosters, such as 6h-on/6h-off split shifts, may offer promise to sleep, subjective sleepiness and performance by limiting shift length and by offering opportunities for all workers to obtain some sleep across the biological night. However, there exists a paucity of studies that have examined these shifts using objective measures of sleep and performance. The present study examined neurobehavioural performance, sleepiness and sleep during 6h-on/6h-off split sleep schedules. Sixteen healthy adults (6 males, 26.13 y ± 4.46) participated in a 9-day laboratory study that included two baseline nights (BL, 10h time in bed (TIB), 2200 h-0800 h), 4 days on one of two types of 6h-on/6h-off split sleep schedules with 5h TIB during each 'off' period (6h early: TIB 0300 h-0800 h and 1500 h-20000 h, or 6-h late: TIB 0900 h-1400 h and 2100 h-0200 h), and two recovery nights (10h TIB per night, 2200 h-0800 h). Participants received 10h TIB per 24h in total across both shift schedules. A neurobehavioural test bout was completed every 2 h during wake, which included the Psychomotor Vigilance Task (PVT) and the Karolinska Sleepiness Scale (KSS). Linear mixed effects models were used to assess the effect of day (BL, shift days 1-4), schedule (6h early, 6h late) and trial (numbers 1-6) on PVT lapses (operationalised as the number of reaction times >500 ms), PVT total lapse time, PVT fastest 10% of reaction times and KSS. Analyses were also conducted examining the effect of day and schedule on sleep variables. Overall, PVT lapses and total lapse time did not differ significantly between baseline and shift days, however, peak response speeds were significantly slower on the first shift day when compared to baseline, but only for those in the 6h-late condition. Circadian variations were apparent in performance outcomes, with individuals in the 6h-late condition demonstrated significantly more and longer lapses and slower peak reaction times at the end of their night shift (0730 h) than at any other time during their shifts. In the 6h-early condition, only response speed significantly differed across trials, with slower response speeds occurring at trial 1 (0930 h) than in trials 3 (1330 h) or 4 (2130 h). While subjective sleepiness was higher on shift days than at baseline, sleepiness did not accumulate across days. Total sleep was reduced across split sleep schedules compared to baseline. Overall, these results show that while there was not a cumulative cost to performance across days of splitting sleep, participants obtained less sleep and reported lowered alertness on shift days. Tests near the circadian nadir showed higher sleepiness and increased performance deficits. While this schedule did not produce cumulative impairment, the performance deficits witnessed during the biological night are still of operational concern for industry and workers alike. Crown Copyright © 2015. Published by Elsevier Ltd. All rights reserved.

Differential influence of asynchrony in early and late chronotypes on convergent thinking.

PubMed

Simor, Péter; Polner, Bertalan

2017-01-01

Eveningness preference (late chronotype) was previously associated with different personality dimensions and thinking styles that were linked to creativity, suggesting that evening-type individuals tend to be more creative than the morning-types. Nevertheless, empirical data on the association between chronotype and creative performance is scarce and inconclusive. Moreover, cognitive processes related to creative thinking are influenced by other factors such as sleep and the time of testing. Therefore, our aim was to examine convergent and divergent thinking abilities in late and early chronotypes, taking into consideration the influence of asynchrony (optimal versus nonoptimal testing times) and sleep quality. We analyzed the data of 36 evening-type and 36 morning-type young, healthy adults who completed the Compound Remote Associates (CRAs) as a convergent and the Just suppose subtest of the Torrance Tests of Creative Thinking as a divergent thinking task within a time interval that did (n = 32) or did not (n = 40) overlap with their individually defined peak times. Chronotype was not directly associated with creative performance, but in case of the convergent thinking task an interaction between chronotype and asynchrony emerged. Late chronotypes who completed the test at subjectively nonoptimal times showed better performance than late chronotypes tested during their "peak" and early chronotypes tested at their peak or off-peak times. Although insomniac symptoms predicted lower scores in the convergent thinking task, the interaction between chronotype and asynchrony was independent of the effects of sleep quality or the general testing time. Divergent thinking was not predicted by chronotype, asynchrony or their interaction. Our findings indicate that asynchrony might have a beneficial influence on convergent thinking, especially in late chronotypes.

24 hours on-call and acute fatigue no longer worsen resident mood under the 80-hour work week regulations.

PubMed

Kiernan, Michael; Civetta, Joseph; Bartus, Christine; Walsh, Stephen

2006-01-01

Studies in on-call residents have shown that mood is worsened by fatigue as indicated by increased scores on measures of depression, anxiety, confusion, and anger using the Profile of Mood States (POMS). In prior sleep deprivation studies, mood has been shown to be more affected than either cognitive or motor performances. The purpose of this study was to examine the effect of the 80-hour work week regulations on resident mood in general and in a post-call period (PC). Institutional Review Board approval was obtained to survey the residents and publish the results. POMS is a 65-item adjective questionnaire that includes subscales for measuring tension-anxiety, anger-hostility, depression-dejection, vigor-activity, fatigue-inertia, and confusion-bewilderment, with the summation of the scales forming a total mood disturbance score. Surgical residents were tested at a 9 am didactic curriculum session (9 am has been shown to correlate with the nadir of performance). Residents were tested after nights off call (NOC) or after PC. Time asleep in the preceding 24 hours and other demographic data were also collected. Acute fatigue (AF) was defined as <4 hours sleep. The two-sample t-test and linear regression were used to assess differences between groups. A total of 123 standardized POMS mood questionnaires were administered on 4 occasions to 51 surgical residents, 35 men and 16 women at levels PGY-1 through PGY-5. Overall, 33 tests (27%) were taken after PC and 90 (73%) were taken after NOC. Acute fatigue residents had a mean sleep time of 2.2 (+/-1.5) hours, whereas rested (R) residents had a mean sleep time of 6.7 (+/-2.2) hours (whether PC or NOC). No statistical differences in mean values of vigor, anger, depression, concentration, fatigue, tension, or total score were observed between PC and NOC or between AF and R residents. There was no significant relationship between acute sleep deprivation and total mood disturbance, whether PC or NOC. In linear relationships, NOC total score and hours slept had r2 = 0.01 (p = 0.44), whereas PC total score and hours slept had r2 = 0.07 (p = 0.14). Although POMS was given 4 times, only 27% were PC, which reflects our 1 in 4 night in-house coverage. In contrast to earlier studies, resident mood, as measured by POMS, is no longer related to PC/NOC or acute fatigue. Previous studies have shown that loss of sleep was associated with declining mood. The lack of such a relationship in this study may be related to the new regulations. It has been assumed that people can adapt to chronic sleep loss but have a harder time coping with the effects of acute sleep deprivation. If, however, the new regulations have relieved chronic sleep deprivation, then a well-rested resident can periodically cope with the effects of acute sleep deprivation. Perhaps by eliminating chronic sleep debt, work hour restrictions seem to have removed the negative impact of PC seen in the prior era. Further studies should increase the number of residents studied, have numerous repeat NOC and PC pairs in same subjects, compare different services with different workloads, junior and senior residents, and in-house and at-home call schedules.

Noise emitted from road, rail and air traffic and their effects on sleep

NASA Astrophysics Data System (ADS)

Griefahn, Barbara; Marks, Anke; Robens, Sibylle

2006-08-01

This study compared the effects of road, rail, and aircraft noise and tested the applicability of the equivalent noise level for the evaluation of sleep disturbances. Sixteen women and 16 men (19-28 years) slept during 3 consecutive weeks in the laboratory. Eight persons slept in quiet throughout. Twenty-four persons were exposed to road, rail, or aircraft noise with weekly permuted changes. Each week consisted of a random sequence of a quiet night (32 dBA) and 3 nights with equivalent noise levels of 39, 44, and 50 dBA and maximum levels of 50-62, 56-68, and 62-74 dBA, respectively. The polysomnogram was recorded during all nights, sleep quality was assessed and performance tests were completed in the morning. Subjectively evaluated sleep quality decreased and reaction time increased gradually with noise levels, whereas most physiological variables revealed the same reactions to both the lower and considerably stronger reactions to the highest noise load. Aircraft noise, rail and road traffic noise caused similar after-effects but physiological sleep parameters were most severely affected by rail noise. The equivalent noise level seems to be a suitable predictor for subjectively evaluated sleep quality but not for physiological sleep disturbances.

The impact of sleep on true and false memory across long delays.

PubMed

Pardilla-Delgado, Enmanuelle; Payne, Jessica D

2017-01-01

While the influence of sleep on memory has a long history, sleep's role in the formation of false memories is less clear. Moreover, virtually nothing is known about the development of false memories beyond delays of about 12h. Here, for the first time, we assess post-sleep development of true and false memories across longer delay intervals of 24 and 48h. Although technically a false memory, remembering information that is related to the theme, or gist, of an experience can be considered an adaptive process. Some evidence suggests that sleep, compared to a wake period, increases both true and gist-based false memories in the Deese-Roediger-McDermott (DRM) task, but not all studies have returned this result, and most studies cannot rule out the possibility that sleep is merely protecting the information from interference, as opposed to actively aiding its consolidation. Here, to equate amount of time spent awake and asleep across groups, we assess how the positioning of sleep relative to memory encoding impacts retention across longer delays of 24 and 48h. Participants encoded 16 DRM lists in the morning (WAKE 1st Groups) or evening (SLEEP 1st Groups), and were tested either 24 or 48h later at the same time of day. Results demonstrate that true memory is better when participants sleep soon after learning. Sleeping first also increased false memory, but only in low performers. Importantly, and similar to previous studies, we found a negative correlation between slow-wave sleep (SWS) and false memory, suggesting that SWS may be detrimental for semantic/gist processing. Copyright © 2016 Elsevier Inc. All rights reserved.

Effects on subjective and objective alertness and sleep in response to evening light exposure in older subjects

PubMed Central

Münch, M; Scheuermaier, KD; Zhang, R; Dunne, SP; Guzik, AM; Silva, EJ; Ronda, JM; Duffy, JF

2011-01-01

Evening bright light exposure is reported to ameliorate daytime sleepiness and age-related sleep complaints, and also delays the timing of circadian rhythms. We tested whether evening light exposure given to older adults with sleep-wake complaints would delay the timing of their circadian rhythms with respect to their sleep timing, thereby reducing evening sleepiness and improving subsequent sleep quality. We examined the impact of evening light exposure from two different light sources on subjective alertness, EEG activity during wakefulness, and sleep stages. Ten healthy older adults with sleep complaints (mean age=63.3 yrs; 6F) participated in a 13-day study. After three baseline days, circadian phase was assessed. On the evening of days 5–8 the subjects were exposed for 2 h to either polychromatic blue-enriched white light or standard white fluorescent light, and on the following day circadian phase was re-assessed. Subjects were allowed to leave the laboratory during all but the two days when the circadian phase assessment took place. Evening assessments of subjective alertness, and wake and sleep EEG data were analyzed. Subjective alertness and wake EEG activity in the alpha range (9.75–11.25 Hz) were significantly higher during light exposures when compared to the pre-light exposure evening (p<0.05). The light exposures produced circadian phase shifts and significantly prolonged latency to rapid eye-movement (REM) sleep for both light groups (p<0.05). The increase in wake EEG alpha activity during the light exposures was negatively correlated with REM sleep duration (p<0.05). Evening light exposure could benefit older adults with early evening sleepiness, without negatively impacting the subsequent sleep episode. PMID:21664380

Technology Use and Sleep Quality in Preadolescence and Adolescence.

PubMed

Bruni, Oliviero; Sette, Stefania; Fontanesi, Lilybeth; Baiocco, Roberto; Laghi, Fiorenzo; Baumgartner, Emma

2015-12-15

The purpose of this study was to analyze differences between preadolescents and adolescents on the use of technology and to test the contribution of using Internet and mobile phone, and circadian preference on sleep quality. We recruited a sample of 850 (364 males) preadolescents and adolescents. Self-report questionnaires about sleep schedule, sleep wake behavior problems, circadian preferences, and the use of technology (e.g., Internet and mobile phone) were administered. Students were asked to fill out the School Sleep Habits Survey, a self-report questionnaire on the use of technology, the Mobile Phone Involvement Questionnaire (MPIQ), and the Shorter Promis Questionnaire (SPQ). Adolescents reported more sleep problems, a tendency toward eveningness, and an increase of Internet and phone activities, as well as social network activities, while preadolescents were more involved in gaming console and television viewing. The regression analysis performed separately in the two age groups showed that sleep quality was affected by the circadian preference (eveningness) in both groups. Adolescents' bad sleep quality was consistently associated with the mobile phone use and number of devices in the bedroom, while in preadolescents, with Internet use and turning-off time. The evening circadian preference, mobile phone and Internet use, numbers of other activities after 21:00, late turning off time, and number of devices in the bedroom have different negative influence on sleep quality in preadolescents and adolescents. © 2015 American Academy of Sleep Medicine.

Validation of the Behavioral Risk Factor Surveillance System Sleep Questions

PubMed Central

Jungquist, Carla R.; Mund, Jaime; Aquilina, Alan T.; Klingman, Karen; Pender, John; Ochs-Balcom, Heather; van Wijngaarden, Edwin; Dickerson, Suzanne S.

2016-01-01

Study Objective: Sleep problems may constitute a risk for health problems, including cardiovascular disease, depression, diabetes, poor work performance, and motor vehicle accidents. The primary purpose of this study was to assess the validity of the current Behavioral Risk Factor Surveillance System (BRFSS) sleep questions by establishing the sensitivity and specificity for detection of sleep/ wake disturbance. Methods: Repeated cross-sectional assessment of 300 community dwelling adults over the age of 18 who did not wear CPAP or oxygen during sleep. Reliability and validity testing of the BRFSS sleep questions was performed comparing to BFRSS responses to data from home sleep study, actigraphy for 14 days, Insomnia Severity Index, Epworth Sleepiness Scale, and PROMIS-57. Results: Only two of the five BRFSS sleep questions were found valid and reliable in determining total sleep time and excessive daytime sleepiness. Conclusions: Refinement of the BRFSS questions is recommended. Citation: Jungquist CR, Mund J, Aquilina AT, Klingman K, Pender J, Ochs-Balcom H, van Wijngaarden E, Dickerson SS. Validation of the behavioral risk factor surveillance system sleep questions. J Clin Sleep Med 2016;12(3):301–310. PMID:26446246

Associations among sleep, daily experiences, and loneliness in adolescence: evidence of moderating and bidirectional pathways.

PubMed

Doane, Leah D; Thurston, Emily C

2014-02-01

The present study examined the dynamic associations among daily stress levels, affect, and objective sleep quality in adolescence. We also explored loneliness as a potential moderator of these associations. Seventy-eight adolescents participated over three days. They completed diary reports of stressful experiences and affect five times a day while wearing an actigraph to obtain objective measurement of sleep. They also provided self-reports of loneliness. High daily stress was associated with shorter sleep duration. Models testing bidirectional associations indicated that prior day stress was associated with shorter sleep duration, but poor sleep duration and sleep efficiency were also associated with greater stress the next day. Loneliness was a significant moderator of the associations between daily stress and sleep duration and latency such that lonely individuals had shorter sleep durations and sleep latencies after particularly stressful days. Results suggest daily dynamic associations among loneliness, daily stress, and objective measures of adolescent sleep. Copyright © 2013 The Foundation for Professionals in Services for Adolescents. Published by Elsevier Ltd. All rights reserved.

Sleep and moral awareness.

PubMed

Barnes, Christopher M; Gunia, Brian C; Wagner, David T

2015-04-01

The implications of sleep for morality are only starting to be explored. Extending the ethics literature, we contend that because bringing morality to conscious attention requires effort, a lack of sleep leads to low moral awareness. We test this prediction with three studies. A laboratory study with a manipulation of sleep across 90 participants judging a scenario for moral content indicates that a lack of sleep leads to low moral awareness. An archival study of Google Trends data across 6 years highlights a national dip in Web searches for moral topics (but not other topics) on the Monday after the Spring time change, which tends to deprive people of sleep. Finally, a diary study of 127 participants indicates that (within participants) nights with a lack of sleep are associated with low moral awareness the next day. Together, these three studies suggest that a lack of sleep leaves people less morally aware, with important implications for the recognition of morality in others. © 2014 European Sleep Research Society.

Use of a supplementary internet based education program improves sleep literacy in college psychology students.

PubMed

Quan, Stuart F; Anderson, Janis L; Hodge, Gordon K

2013-02-01

Knowledge regarding the importance of sleep in health and performance and good sleep hygiene practices is low, especially among adolescents and young adults. It is important to improve sleep literacy. Introductory psychology is one of the most highly enrolled courses at colleges and universities. This study tested the impact of an Internet-based learning module on improving sleep literacy in this venue. An Internet-based supplementary learning module containing sleep physiology and hygiene information was developed using content from the Harvard Medical School sleep educational website http://www.understandingsleep.org. Access to the module was provided as an extra credit activity for 2 of 4 sections (Supplemental Sleep, SS, N = 889) of an introductory college psychology course during their standard instruction on sleep and dreaming. The remaining 2 sections (Standard Instruction, SI, N = 878) only were encouraged to visit the website without further direction. Level of knowledge was assessed before and after availability to the module/website and at the end of the semester. Students were asked to complete a survey at the end of the semester inquiring whether they made any changes in their sleep behaviors. Two hundred fifty students participated in the extra credit activity and had data available at all testing points. Students in the SS Group had a significant improvement in sleep knowledge test scores after interacting with the website in comparison to the SI group (19.41 ± 3.15 vs. 17.94 ± 3.08, p < 0.001). This difference persisted, although at a lower level, at the end of the semester. In addition, 55.9% of the SS group versus 45.1% of the SI group indicated that they made changes in their sleep habits after participation in the extra credit sleep activity (p < 0.01). The most common change was a more consistent wake time. Use of a supplementary internet-based sleep learning module has the potential to enhance sleep literacy and change behavior among students enrolled in an introductory college psychology course.

Effects of Zolpidem CR on Sleep and Nocturnal Ventilation in Patients with Heart Failure.

PubMed

Gatti, Rodrigo C; Burke, Patrick R; Otuyama, Leonardo J; Almeida, Dirceu R; Tufik, Sergio; Poyares, Dalva

2016-08-01

This study aimed to evaluate the effects of zolpidem CR (controlled release) on sleep and nocturnal ventilation in patients with congestive heart failure, a population at risk for insomnia and poor sleep quality. Fifteen patients with heart failure (ischemic cardiomyopathy) and ejection fraction ≤ 45% in NYHA functional class I or II were evaluated with full polysomnography in a placebo-controlled, double-blind, randomized trial. Patients underwent three tests: (1) baseline polysomnography and, after randomization, (2) a new test with zolpidem CR 12.5 mg or placebo, and after 1 week, (3) a new polysomnography, crossing the "medication" used. A 16% increase in total sleep time was found with the use of zolpidem CR and an increase in stage 3 NREM sleep (slow wave sleep). The apnea hypopnea index (AHI) did not change with zolpidem CR even after controlling for supine position; however, a slight but significant decrease was observed in lowest oxygen saturation compared with baseline and placebo conditions (83.60 ± 5.51; 84.43 ± 3.80; 80.71 ± 5.18, P = 0.002). Zolpidem CR improved sleep structure in patients with heart failure, did not change apnea hypopnea index, but slightly decreased lowest oxygen saturation. © 2016 Associated Professional Sleep Societies, LLC.

Sleep restriction alters the hypothalamic-pituitary-adrenal response to stress

NASA Technical Reports Server (NTRS)

Meerlo, P.; Koehl, M.; van der Borght, K.; Turek, F. W.

2002-01-01

Chronic sleep restriction is an increasing problem in many countries and may have many, as yet unknown, consequences for health and well being. Studies in both humans and rats suggest that sleep deprivation may activate the hypothalamic-pituitary-adrenal (HPA) axis, one of the main neuroendocrine stress systems. However, few attempts have been made to examine how sleep loss affects the HPA axis response to subsequent stressors. Furthermore, most studies applied short-lasting total sleep deprivation and not restriction of sleep over a longer period of time, as often occurs in human society. Using the rat as our model species, we investigated: (i) the HPA axis activity during and after sleep deprivation and (ii) the effect of sleep loss on the subsequent HPA response to a novel stressor. In one experiment, rats were subjected to 48 h of sleep deprivation by placing them in slowly rotating wheels. Control rats were placed in nonrotating wheels. In a second experiment, rats were subjected to an 8-day sleep restriction protocol allowing 4 h of sleep each day. To test the effects of sleep loss on subsequent stress reactivity, rats were subjected to a 30-min restraint stress. Blood samples were taken at several time points and analysed for adrenocorticotropic hormone (ACTH) and corticosterone. The results show that ACTH and corticosterone concentrations were elevated during sleep deprivation but returned to baseline within 4 h of recovery. After 1 day of sleep restriction, the ACTH and corticosterone response to restraint stress did not differ between control and sleep deprived rats. However, after 48 h of total sleep deprivation and after 8 days of restricted sleep, the ACTH response to restraint was significantly reduced whereas the corticosterone response was unaffected. These results show that sleep loss not only is a mild activator of the HPA axis itself, but also affects the subsequent response to stress. Alterations in HPA axis regulation may gradually appear under conditions of long total sleep deprivation but also after repeated sleep curtailment.

Electrophysiological assessment of the effects of obstructive sleep apnea on cognition.

PubMed

Gelir, Ethem; Başaran, Cenk; Bayrak, Sibel; Yağcıoğlu, Süha; Budak, Murat Timur; Fırat, Hikmet; Ungan, Pekcan

2014-01-01

We used electrophysiological measures to investigate the effects of obstructive sleep apnea on attention, learning, and memory. Thirty subjects (OSA group, n = 15, control group n = 15) participated in n-back tests, accompanied by P300 recordings, to investigate working memory and attention. The mirror-drawing test was used to study procedural memory, and the trail-making test (TMT) was used to evaluate divided attention and executive function. No significant group difference in reaction time was found in the 0-back and 1-back tests. In the 2-back test, reaction times of patients were longer than those of the control group. No P300 wave was obtained in the OSA group in any (0-, 1-, or 2-back) n-back test. In contrast, in the control group, significant P300 waves were recorded except for the 2-back test. The mirror-drawing scores were unaffected by sleep apnea. There was no difference between groups in the TMT-A test on any of the trials. Although no group difference was found in the first or second trials of the TMT-B test, OSA patients were less successful in learning on the third trial. According to our study results, OSA affects attention and executive function adversely however, we could not detect a significant effect on working or procedural memory.

Advancing the sleep/wake schedule impacts the sleep of African-Americans more than European-Americans

PubMed Central

Crowley, Stephanie J.; Fogg, Louis F.; Eastman, Charmane I.

2017-01-01

There are differences in sleep duration between Blacks/African-Americans and Whites/European-Americans. Recently, we found differences between these ancestry groups in the circadian system, such as circadian period and the magnitude of phase shifts. Here we document the role of ancestry on sleep and cognitive performance before and after a 9-h advance in the sleep/wake schedule similar to flying east or having a large advance in sleep times due to shiftwork, both of which produce extreme circadian misalignment. Non-Hispanic African and European-Americans (N = 20 and 17 respectively, aged 21–43 years) were scheduled to four baseline days each with 8 h time in bed based on their habitual sleep schedule. This sleep/wake schedule was then advanced 9 h earlier for three days. Sleep was monitored using actigraphy. During the last two baseline/aligned days and the first two advanced/misaligned days, beginning 2 h after waking, cognitive performance was measured every 3 h using the Automated Neuropsychological Assessment Metrics (ANAM) test battery. Mixed model ANOVAs assessed the effects of ancestry (African-American or European-American) and condition (baseline/aligned or advanced/misaligned) on sleep and cognitive performance. There was decreased sleep and impaired performance in both ancestry groups during the advanced/misaligned days compared to the baseline/aligned days. In addition, African-Americans obtained less sleep than European-Americans, especially on the first two days of circadian misalignment. Cognitive performance did not differ between African-Americans and European-Americans during baseline days. During the two advanced/misaligned days, however, African-Americans tended to perform slightly worse compared to European-Americans, particularly at times corresponding to the end of the baseline sleep episodes. Advancing the sleep/wake schedule, creating extreme circadian misalignment, had a greater impact on the sleep of African-Americans than European-Americans. Ancestry differences in sleep appear to be exacerbated when the sleep/wake schedule is advanced, which may have implications for individuals undertaking shiftwork and transmeridian travel. PMID:29059251

Assessment Of Noise-induced Sleep Fragility In Two Age Ranges By Means Of Polysomnographic Microstructure

NASA Astrophysics Data System (ADS)

Terzano, M. G.; Parrino, L.; Spaggiari, M. C.; Buccino, G. P.; Fioriti, G.; Depoortere, H.

1993-04-01

The microstructure of sleep, which translates the short-lived fluctuations of the arousal level, is a commonly neglected feature in polysomnographic studies. Specifically arranged microstructural EEG events may provide important information on the dynamic characteristics of the sleep process. CAP (cyclic alternating pattern) and non-CAP are complementary modalities in which arousal-related "phasic" EEG phenomena are organized in non-REM sleep, and they correspond to opposite conditions of unstable and stable sleep depth, respectively. Thus, arousal instability can be measured by the CAP rate, the percentage ratio of total CAP time to total non-REM sleep time. The CAP rate, an age-related physiological variable that increases in several pathological conditions, is highly sensitive to acoustic perturbation. In the present study, two groups of healthy subjects without complaints about sleep, belonging to different age ranges (six young adults, three males and three females, between 20 and 30 years, and six middle-aged individuals, three males and three females, between 40 and 55 years) slept, after adaptation to the sleep laboratory, in a random sequence for two non-consecutive nights either under silent baseline (27·3 dB(A) Lcq) or noise-disturbed (continuous 55 dB(A) white noise) conditions. Age-related and noise-related effects on traditional sleep parameters and on the CAP rate were statistically evaluated by a split-plot test. Compared to young adults, the middle-aged individuals showed a significant reduction of total sleep time, stage 2 and REM sleep and significantly higher values of nocturnal awakenings and the CAP rate. The noisy nights were characterized by similar alterations. The disruptive effects of acoustic perturbation were greater on the more fragile sleep architecture of the older group. The increased fragility of sleep associated with aging probably reflects the decreased capacity of the sleeping brain to maintain steady states of vigilance. Total non-REM sleep described by traditional parameters was statistically unaffected during the disturbed nights, but the perturbing effects of noise on non-REM sleep stability and continuity were revealed by a significant increase in the CAP rate. The perspectives for a wide-ranging exploitation of this sleep parameter are discussed.

Sleep restriction and cognitive load affect performance on a simulated marksmanship task.

PubMed

Smith, Carl D; Cooper, Adam D; Merullo, Donna J; Cohen, Bruce S; Heaton, Kristin J; Claro, Pedro J; Smith, Tracey

2017-11-24

Sleep restriction degrades cognitive and motor performance, which can adversely impact job performance and increase the risk of accidents. Military personnel are prone to operating under sleep restriction, and previous work suggests that military marksmanship may be negatively affected under such conditions. Results of these studies, however, are mixed and have often incorporated additional stressors (e.g. energy restriction) beyond sleep restriction. Moreover, few studies have investigated how the degree of difficulty of a marksmanship task impacts performance following sleep restriction. The purpose of the current experiment was to study the effects of sleep restriction on marksmanship while minimizing the potential influence of other forms of stress. A friend-foe discrimination challenge with greater or lesser degrees of complexity (high versus low load) was used as the primary marksmanship task. Active duty Soldiers were recruited, and allowed 2 h of sleep every 24 h over a 72-h testing period. Marksmanship tasks, cognitive assessment metrics and the NASA-Task Load Index were administered daily. Results indicated that reaction times to shoot foe targets and signal friendly targets slowed over time. In addition, the ability to correctly discriminate between friend and foe targets significantly decreased in the high-cognitive-load condition over time despite shot accuracy remaining stable. The NASA-Task Load Index revealed that, although marksmanship performance degraded, participants believed their performance did not change over time. These results further characterize the consequences of sleep restriction on marksmanship performance and the perception of performance, and reinforce the importance of adequate sleep among service members when feasible. Published 2017. This article is a U.S. Government work and is in the public domain in the USA.

Sleep architecture and sleep-related mentation in securely and insecurely attached people

PubMed Central

McNamara, Patrick; Pace-Schott, Edward F.; Johnson, Patricia; Harris, Erica; Auerbach, Sanford

2011-01-01

Based on REM sleep’s brain activation patterns and its participation in consolidation of emotional memories, we tested the hypothesis that measures of REM sleep architecture and REM sleep-related mentation would be associated with attachment orientation. After a habituation night in a sleep lab, a convenience sample of 64 healthy volunteers were awakened 10 minutes into a REM sleep episode and 10 minutes into a control NREM sleep episode in counterbalanced order, then asked to report a dream and to rate themselves and a significant other on a list of trait adjectives. Relative to participants classified as having secure attachment orientations, participants classified as anxious took less time to enter REM sleep and had a higher frequency of REM dreams with aggression and self-denigrating themes. There were no significant differences across attachment groups in other measures of sleep architecture or in post REM-sleep awakening ratings on PANAS subscales reflecting mood and alertness. Selected aspects of REM sleep architecture and mentation appeared to be associated with attachment orientation. We suggest that REM sleep plays a role in processing experiences and emotions related to attachment, and that certain features of sleep and dreaming reflect attachment orientations. PMID:21390907

Classifying performance impairment in response to sleep loss using pattern recognition algorithms on single session testing

PubMed Central

St. Hilaire, Melissa A.; Sullivan, Jason P.; Anderson, Clare; Cohen, Daniel A.; Barger, Laura K.; Lockley, Steven W.; Klerman, Elizabeth B.

2012-01-01

There is currently no “gold standard” marker of cognitive performance impairment resulting from sleep loss. We utilized pattern recognition algorithms to determine which features of data collected under controlled laboratory conditions could most reliably identify cognitive performance impairment in response to sleep loss using data from only one testing session, such as would occur in the “real world” or field conditions. A training set for testing the pattern recognition algorithms was developed using objective Psychomotor Vigilance Task (PVT) and subjective Karolinska Sleepiness Scale (KSS) data collected from laboratory studies during which subjects were sleep deprived for 26 – 52 hours. The algorithm was then tested in data from both laboratory and field experiments. The pattern recognition algorithm was able to identify performance impairment with a single testing session in individuals studied under laboratory conditions using PVT, KSS, length of time awake and time of day information with sensitivity and specificity as high as 82%. When this algorithm was tested on data collected under real-world conditions from individuals whose data were not in the training set, accuracy of predictions for individuals categorized with low performance impairment were as high as 98%. Predictions for medium and severe performance impairment were less accurate. We conclude that pattern recognition algorithms may be a promising method for identifying performance impairment in individuals using only current information about the individual’s behavior. Single testing features (e.g., number of PVT lapses) with high correlation with performance impairment in the laboratory setting may not be the best indicators of performance impairment under real-world conditions. Pattern recognition algorithms should be further tested for their ability to be used in conjunction with other assessments of sleepiness in real-world conditions to quantify performance impairment in response to sleep loss. PMID:22959616

Reduction of alcohol induced sleep time in albino mice by potentized Nux vomica prepared with 90% ethanol.

PubMed

Sukul, A; Sinhabau, S P; Sukul, N C

1999-04-01

Male adult albino mice were administered potentized Nux vomica 30 c (Nux v). The drug was mixed with sterile distilled water at 0.05 ml/2 ml water and given at 0.05 ml/individual. Control consisted of blank ethanol solution. Ethanolic extract from the seeds of Strychnos nuxvomica L was mixed with 90% ethanol 1:100 and sonicated for 30 s at 20 KHz. This was further diluted and sonicated in 30 steps to produce Nux v 30 c. Six hours after treatment, mice were given 25% ethanol i.p. at 4 g/kg body wt. The duration of sleep time starting from the loss of righting reflex until its restoration was recorded for each mouse. The duration of sleep time with ethanol was recorded in four sessions for the same group of mice with an interval of 10 d between sessions. session 1 with control solution, 2 with Nux v (oral), 3 with control solution and 4 with Nux v (i.p.). Nux v (oral) produced the shortest sleep time as compared to other treatments which did not differ from each other significantly with respect to sleep time. In another experiment Nux v 30 c was prepared with distilled water and pure absolute ethanol by the above process of successive dilution and sonication. These two preparations together with Nux v 30 c, prepared with 90% ethanol, were tested on mice for their effect on alcohol-induced sleep time. Only Nux v 30 c prepared with 90% ethanol was effective in reducing the sleep time in mice. It is concluded that the solution structure of ethanol/water mixture carries the specificity of the Nux v at ultra high dilution. It is further concluded that the effect is mediated through oral receptors.

A multi-step pathway connecting short sleep duration to daytime somnolence, reduced attention, and poor academic performance: an exploratory cross-sectional study in teenagers.

PubMed

Perez-Lloret, Santiago; Videla, Alejandro J; Richaudeau, Alba; Vigo, Daniel; Rossi, Malco; Cardinali, Daniel P; Perez-Chada, Daniel

2013-05-15

A multi-step causality pathway connecting short sleep duration to daytime somnolence and sleepiness leading to reduced attention and poor academic performance as the final result can be envisaged. However this hypothesis has never been explored. To explore consecutive correlations between sleep duration, daytime somnolence, attention levels, and academic performance in a sample of school-aged teenagers. We carried out a survey assessing sleep duration and daytime somnolence using the Pediatric Daytime Sleepiness Scale (PDSS). Sleep duration variables included week-days' total sleep time, usual bedtimes, and absolute weekday to-weekend sleep time difference. Attention was assessed by d2 test and by the coding subtest from the WISC-IV scale. Academic performance was obtained from literature and math grades. Structural equation modeling was used to assess the independent relationships between these variables, while controlling for confounding effects of other variables, in one single model. Standardized regression weights (SWR) for relationships between these variables are reported. Study sample included 1,194 teenagers (mean age: 15 years; range: 13-17 y). Sleep duration was inversely associated with daytime somnolence (SWR = -0.36, p < 0.01) while sleepiness was negatively associated with attention (SWR = -0.13, p < 0.01). Attention scores correlated positively with academic results (SWR = 0.18, p < 0.01). Daytime somnolence correlated negatively with academic achievements (SWR = -0.16, p < 0.01). The model offered an acceptable fit according to usual measures (RMSEA = 0.0548, CFI = 0.874, NFI = 0.838). A Sobel test confirmed that short sleep duration influenced attention through daytime somnolence (p < 0.02), which in turn influenced academic achievements through reduced attention (p < 0.002). Poor academic achievements correlated with reduced attention, which in turn was related to daytime somnolence. Somnolence correlated with short sleep duration.

Effects of Sleep Deprivation on the Cognitive Performance of Nurses Working in Shift.

PubMed

Kaliyaperumal, Deepalakshmi; Elango, Yaal; Alagesan, Murali; Santhanakrishanan, Iswarya

2017-08-01

Sleep deprivation and altered circadian rhythm affects the cognitive performance of an individual. Quality of sleep is compromised in those who are frequently involved in extended working hours and shift work which is found to be more common among nurses. Cognitive impairment leads to fatigability, decline in attention and efficiency in their workplace which puts their health and patients' health at risk. To find out the prevalence of sleep deprivation and its impact on cognition among shift working nurses. Sleep deprivation among 97 female and three male healthy nurses of age 20-50 years was assessed by Epworth sleepiness scale (ESS). Cognition was assessed by Montreal Cognitive Assessment (MoCA) questionnaire. Mobile applications were used to test their vigilance, reaction time, photographic memory and numerical cognition. The above said parameters were assessed during end of day shift and 3-4 days after start of night shift. Poor sleep quality was observed among 69% of shift working nurses according to ESS scores. The cognitive performance was analysed using Wilcoxon signed rank test. The MoCA score was found to be lesser among 66% of nurses during night (25.72) than day (26.81). During the night, 32% made more mathematical errors. It was also found that, 71%, 83% and 68% of the nurses scored lesser during night in the Stroop's colour test, vigilance test and memory tests respectively. Thus, impairment in cognitive performance was statistically significant (p<0.001) among shift working nurses. Cognitive performance was found to be impaired among shift working nurses, due to poor sleep quality and decreased alertness during wake state. Thus, shift work poses significant cognitive risks in work performance of nurses.

Napping Reduces Emotional Attention Bias during Early Childhood

ERIC Educational Resources Information Center

Cremone, Amanda; Kurdziel, Laura B. F.; Fraticelli-Torres, Ada; McDermott, Jennifer M.; Spencer, Rebecca M. C.

2017-01-01

Sleep loss alters processing of emotional stimuli in preschool-aged children. However, the mechanism by which sleep modifies emotional processing in early childhood is unknown. We tested the hypothesis that a nap, compared to an equivalent time spent awake, reduces biases in attention allocation to affective information. Children (n = 43;…

The Degree of Radiation-Induced DNA Strand Breaks Is Altered by Acute Sleep Deprivation and Psychological Stress and Is Associated with Cognitive Performance in Humans.

PubMed

Moreno-Villanueva, Maria; von Scheven, Gudrun; Feiveson, Alan; Bürkle, Alexander; Wu, Honglu; Goel, Namni

2018-03-27

Sleep deprivation is associated with impaired immune responses, cancer, and morbidity and mortality, and can degrade cognitive performance, although individual differences exist in such responses. Sleep deprivation induces DNA strand breaks and DNA base oxidation in animals, and psychological stress is associated with increased DNA damage in humans. It remains unknown whether sleep deprivation or psychological stress in humans affects DNA damage response from environmental stressors, and whether these responses predict cognitive performance during sleep deprivation. Sixteen healthy adults (ages 29-52;mean age±SD, 36.4±7.1 years;7 women) participated in a 5-day experiment involving two 8 hour time-in-bed [TIB] baseline nights, followed by 39 hours total sleep deprivation (TSD), and two 8-10 hour TIB recovery nights. A modified Trier Social Stress Test was conducted on the day after TSD. Psychomotor Vigilance Tests measured behavioral attention. DNA damage was assessed in blood cells collected at 5 time points, and blood cells were irradiated ex-vivo. TSD, alone or in combination with psychological stress, did not induce significant increases in DNA damage. By contrast, radiation-induced DNA damage decreased significantly in response to TSD, but increased back to baseline when combined with psychological stress. Cognitively-vulnerable individuals had more radiation-induced DNA strand breaks before TSD, indicating their greater sensitivity to DNA damage from environmental stressors. Our results provide novel insights into the molecular consequences of sleep deprivation, psychological stress, and performance vulnerability. They are important for situations involving sleep loss, radiation exposure and cognitive deficits, including cancer therapy, environmental toxicology, and space medicine.

Effects of Time of Day and Sleep Deprivation on Motorcycle-Driving Performance

PubMed Central

Bougard, Clément; Espié, Stéphane; Larnaudie, Bruno; Moussay, Sébastien; Davenne, Damien

2012-01-01

The aim of this study was to investigate whether motorcycle handling capabilities – measured by means of the efficiency of emergency manoeuvres – were dependent on prior sleep deprivation and time of day. Twelve male participants voluntarily took part in four test sessions, starting at 6 a.m., 10 a.m., 2 p.m., and 6 p.m., following a night either with or without sleep. Each test session comprised temperature and sleepiness measurements, before three different types of motorcycling tests were initiated: (1) stability in straight ahead riding at low speed (in “slow motion” mode and in “brakes and clutch” mode), (2) emergency braking and (3) crash avoidance tasks performed at 20 kph and 40 kph. The results indicate that motorcycle control at low speed depends on time of day, with an improvement in performance throughout the day. Emergency braking performance is affected at both speeds by time of day, with poorer performance (longer total stopping distance, reaction time and braking distance) in the morning, and also by sleep deprivation, from measurements obtained at 40 kph (incorrect initial speed). Except for a tendency observed after the sleepless night to deviate from the initial speed, it seems that crash avoidance capabilities are quite unaffected by the two disturbance factors. Consequently, some motorcycle handling capabilities (stability at low speed and emergency braking) change in the same way as the diurnal fluctuation observed in body temperature and sleepiness, whereas for others (crash avoidance) the participants were able to maintain their initial performance level despite the high levels of sleepiness recorded after a sleepless night. Motorcycle riders have to be aware that their handling capabilities are limited in the early morning and/or after sleep deprivation. Both these situations can increase the risk of falls and of being involved in a road accident. PMID:22761881

Executive Functions are not Affected by 24 Hours of Sleep Deprivation: A Color-Word Stroop Task Study.

PubMed

Dixit, Abhinav; Mittal, Tushar

2015-01-01

Sleep is an important factor affecting cognitive performance. Sleep deprivation results in fatigue, lack of concentration, confusion and sleepiness along with anxiety, depression and irritability. Sleep deprivation can have serious consequences in professions like armed forces and medicine where quick decisions and actions need to be taken. Color-Word Stroop task is one of the reliable tests to assess attention and it analyzes the processing of information in two dimensions i.e., reading of words and naming of colour. The evidence regarding the effect of sleep deprivation on Stroop interference is conflicting. The present study evaluated the effect of 24 hours of sleep deprivation on reaction time and interference in Stroop task. The present study was done on 30 healthy male medical student volunteers in the age group of 18-25 years after taking their consent and clearance from Institute Ethics Committee. Recordings of Stroop task were at three times: baseline (between 7-9 am), after 12 hours (7-9 pm) and after 24 hours (7-9 am, next day). The subjects were allowed to perform normal daily activities. The study revealed a significant increase in reaction time after 24 hours of sleep deprivation in comparison to baseline and after 12 hours of sleep deprivation. There was no significant change in interference and facilitation after sleep deprivation in comparison to baseline. The number of errors also did not show any significant change after sleep deprivation. The study indicated that there was slowing of responses without change in executive functions after 24 hours of sleep deprivation. It is probable that 24 hours of sleep deprivation does not bring about change in areas of brain affecting executive functions in healthy individuals who have normal sleep cycle. The present study indicated that in professions like armed forces and medicine working 24 hours at a stretch can lead to decrease in motor responses without affecting information processing and judgment ability.

Insomnia, metabolic rate and sleep restoration.

PubMed

Bonnet, M H; Arand, D L

2003-07-01

Studies have shown occasional evidence of increased physiological activity in patients with primary insomnia. We hypothesized that metabolic rate, as measured by overall oxygen use (VO2), might be a more general index of increased physiological activity. An initial experiment found elevated VO2 both at night and during the day in patients with primary insomnia as compared with matched normal sleepers. A second experiment found significant but more modest increases in VO2 in patients with Sleep State Misperception Insomnia [who complain of poor sleep but who had normal sleep by electroencephalographic (EEG) criteria]. In a third experiment, normal young adults were given caffeine 400 mg three times per day (TID) for 1 week as a means of increasing VO2 and possibly producing other symptoms of insomnia. Participants developed many symptoms consistent with those seen in patients with primary insomnia (poor sleep, increased latency on the Multiple Sleep Latency Test, increasing fatigue despite physiological activation, and increased anxiety on the Minnesota Multiphasic Personality Inventory (MMPI)). In a final experiment, physiological arousal was again produced by caffeine to determine if sleep with elevated arousal would be less restorative. All subjects (Ss) slept for 3.5 h after being given 400 mg of caffeine. During 41 h of sleep deprivation that followed, there was no significant condition difference for the Multiple Sleep Latency Test or mood measures. The results provided only weak support for the idea that sleep is less restorative after physiological arousal.

Lithium Prevents REM Sleep Deprivation-Induced Impairments on Memory Consolidation

PubMed Central

Ota, Simone M.; Moreira, Karin Di Monteiro; Suchecki, Deborah; Oliveira, Maria Gabriela M.; Tiba, Paula A.

2013-01-01

Background: Pre-training rapid eye movement sleep (REMS) deprivation affects memory acquisition and/or consolidation. It also produces major REMS rebound at the cost of waking and slow wave sleep (SWS). Given that both SWS and REMS appear to be important for memory processes, REMS rebound after training may disrupt the organization of sleep cycles, i.e., excessive amount of REMS and/or little SWS after training could be harmful for memory formation. Objective: To examine whether lithium, a drug known to increase SWS and reduce REMS, could prevent the memory impairment induced by pre-training sleep deprivation. Design: Animals were divided in 2 groups: cage control (CC) and REMS-deprived (REMSDep), and then subdivided into 4 subgroups, treated either with vehicle or 1 of 3 doses of lithium (50, 100, and 150 mg/kg) 2 h before training on the multiple trial inhibitory avoidance task. Animals were tested 48 h later to make sure that the drug had been already metabolized and eliminated. Another set of animals was implanted with electrodes and submitted to the same experimental protocol for assessment of drug-induced sleep-wake changes. Subjects: Wistar male rats weighing 300-400 g. Results: Sleep deprived rats required more trials to learn the task and still showed a performance deficit during test, except from those treated with 150 mg/kg of lithium, which also reduced the time spent in REM sleep during sleep recovery. Conclusion: Lithium reduced rapid eye movement sleep and prevented memory impairment induced by sleep deprivation. These results indicate that these phenomena may be related, but cause-effect relationship cannot be ascertained. Citation: Ota SM; Moreira KDM; Suchecki D; Oliveira MGM; Tiba PA. Lithium prevents REM sleep deprivation-induced impairments on memory consolidation. SLEEP 2013;36(11):1677-1684. PMID:24179301

Relationships Between Sleep Quality and Pain-Related Factors for People with Chronic Low Back Pain: Tests of Reciprocal and Time of Day Effects.

PubMed

Gerhart, James I; Burns, John W; Post, Kristina M; Smith, David A; Porter, Laura S; Burgess, Helen J; Schuster, Erik; Buvanendran, Asokumar; Fras, Anne Marie; Keefe, Francis J

2017-06-01

Poor sleep quality among people with chronic low back pain appears to be related to worse pain, affect, poor physical function, and pain catastrophizing. The causal direction between poor sleep and pain remains an open question, however, as does whether sleep quality exerts effects on low back pain differently across the course of the day. This daily diary study examined lagged temporal associations between prior night sleep quality and subsequent day pain, affect, physical function and pain catastrophizing, the reverse lagged temporal associations between prior day pain-related factors and subsequent night sleep quality, and whether the time of day during which an assessment was made moderated these temporal associations. Chronic low back pain patients (n = 105) completed structured electronic diary assessments five times per day for 14 days. Items included patient ratings of their pain, affect, physical function, and pain catastrophizing. Collapsed across all observations, poorer sleep quality was significantly related to higher pain ratings, higher negative affect, lower positive affect, poorer physical function, and higher pain catastrophizing. Lagged analyses averaged across the day revealed that poorer prior night sleep quality significantly predicted greater next day patient ratings of pain, and poorer physical function and higher pain catastrophizing. Prior poorer night sleep quality significantly predicted greater reports of pain, and poorer physical function, and higher pain catastrophizing, especially during the early part of the day. Sleep quality × time of day interactions showed that poor sleepers reported high pain, and negative mood and low function uniformly across the day, whereas good sleepers reported relatively good mornings, but showed pain, affect and function levels comparable to poor sleepers by the end of the day. Analyses of the reverse causal pathway were mostly nonsignificant. Sleep quality appears related not only to pain intensity but also to a wide range of patient mood and function factors. A good night's sleep also appears to offer only temporary respite, suggesting that comprehensive interventions for chronic low back pain not only should include attention to sleep problems but also focus on problems with pain appraisals and coping.

Relationships Between Sleep Quality and Pain-Related Factors for People with Chronic Low Back Pain: Tests of Reciprocal and Time of Day Effects

PubMed Central

Gerhart, James I.; Burns, John W.; Post, Kristina M.; Smith, David A.; Porter, Laura S.; Burgess, Helen J.; Schuster, Erik; Buvanendran, Asokumar; Fras, Anne Marie; Keefe, Francis J.

2016-01-01

Background Poor sleep quality among people with chronic low back pain appears to be related to worse pain, affect, poor physical function and pain catastrophizing. The causal direction between poor sleep and pain remains an open question, however, as does whether sleep quality exerts effects on low back pain differently across the course of the day. Purpose This daily diary study examined lagged temporal associations between prior night sleep quality and subsequent day pain, affect, physical function and pain catastrophizing, the reverse lagged temporal associations between prior day pain-related factors and subsequent night sleep quality, and whether the time of day during which an assessment was made moderated these temporal associations. Methods Chronic low back pain patients (n = 105) completed structured electronic diary assessments five times per day for 14 days. Items included patient ratings of their pain, affect, physical function and pain catastrophizing. Results Collapsed across all observations, poorer sleep quality was significantly related to higher pain ratings, higher negative affect, lower positive affect, poorer physical function and higher pain catastrophizing. Lagged analyses averaged across the day revealed that poorer prior night sleep quality significantly predicted greater next day patient ratings of pain, and poorer physical function and higher pain catastrophizing. Prior poorer night sleep quality significantly predicted greater reports of pain, and poorer physical function, and higher pain catastrophizing, especially during the early part of the day. Sleep Quality × Time of Day interactions showed that poor sleepers reported high pain, and negative mood and low function uniformly across the day, whereas good sleepers reported relatively good mornings, but showed pain, affect and function levels comparable to poor sleepers by the end of the day. Analyses of the reverse causal pathway were mostly nonsignificant. Conclusions Sleep quality appears related not only to pain intensity but also to a wide range of patient mood and function factors. A good night’s sleep also appears to offer only temporary respite, suggesting that comprehensive interventions for chronic low back pain not only should include attention to sleep problems but also focus on problems with pain appraisals and coping. PMID:27844327

A Multi-Step Pathway Connecting Short Sleep Duration to Daytime Somnolence, Reduced Attention, and Poor Academic Performance: An Exploratory Cross-Sectional Study in Teenagers

PubMed Central

Perez-Lloret, Santiago; Videla, Alejandro J.; Richaudeau, Alba; Vigo, Daniel; Rossi, Malco; Cardinali, Daniel P.; Perez-Chada, Daniel

2013-01-01

Background: A multi-step causality pathway connecting short sleep duration to daytime somnolence and sleepiness leading to reduced attention and poor academic performance as the final result can be envisaged. However this hypothesis has never been explored. Objective: To explore consecutive correlations between sleep duration, daytime somnolence, attention levels, and academic performance in a sample of school-aged teenagers. Methods: We carried out a survey assessing sleep duration and daytime somnolence using the Pediatric Daytime Sleepiness Scale (PDSS). Sleep duration variables included week-days' total sleep time, usual bedtimes, and absolute weekdayto-weekend sleep time difference. Attention was assessed by d2 test and by the coding subtest from the WISC-IV scale. Academic performance was obtained from literature and math grades. Structural equation modeling was used to assess the independent relationships between these variables, while controlling for confounding effects of other variables, in one single model. Standardized regression weights (SWR) for relationships between these variables are reported. Results: Study sample included 1,194 teenagers (mean age: 15 years; range: 13-17 y). Sleep duration was inversely associated with daytime somnolence (SWR = -0.36, p < 0.01) while sleepiness was negatively associated with attention (SWR = -0.13, p < 0.01). Attention scores correlated positively with academic results (SWR = 0.18, p < 0.01). Daytime somnolence correlated negatively with academic achievements (SWR = -0.16, p < 0.01). The model offered an acceptable fit according to usual measures (RMSEA = 0.0548, CFI = 0.874, NFI = 0.838). A Sobel test confirmed that short sleep duration influenced attention through daytime somnolence (p < 0.02), which in turn influenced academic achievements through reduced attention (p < 0.002). Conclusions: Poor academic achievements correlated with reduced attention, which in turn was related to daytime somnolence. Somnolence correlated with short sleep duration. Citation: Perez-Lloret S; Videla AJ; Richaudeau A; Vigo D; Rossi M; Cardinali DP; Perez-Chada D. A multi-step pathway connecting short sleep duration to daytime somnolence, reduced attention, and poor academic performance: an exploratory cross-sectional study in teenagers. J Clin Sleep Med 2013;9(5):469-473. PMID:23674938

Effects of exercise with or without light exposure on sleep quality and hormone reponses

PubMed Central

Lee, Hayan; Kim, Sunho; Kim, Donghee

2014-01-01

[Purpose] The objectives of the present study were to determine the effect of sun exposure and aerobic exercise on quality of sleep and investigate sleep-related hormonal responses in college-aged males. [Methods] In this study, the cross-over design was utilized. The subjects (N = 10) without any physical problems or sleep disorders participated in the experimental performed 4 protocols in only sun exposure (for 30 minutes, EG1) protocol, only aerobic exercise (walking and jogging for 30 minutes, EG2) protocol, aerobic exercise with sun exposure (EG3) protocol, and control (no exercise and no sun exposure, EG4) protocol. Each protocol was 5 times per week with one-week break (wash-out period) between protocols to prevent the effects of the previous protocol. Total test period was should be 7 weeks (one week of protocol and one week of break). Before and after each aerobic exercise session, the subjects completed stretching to warm up for 5 to 10 minutes. Surveys consisting of (bedtime, wake-up time, sleep onset latency, and (Pittsburgh Sleep Quality Index (PSQI) were obtained before the test and after each protocol. After each protocol, the following sleep-related hormonal responses were measured: blood concentrations of melatonin, cortisol, epinephrine, and norepinephrine. One-way ANOVA was used to determine differences between protocols. Statistical significance was set at p < 0.05. [Results] Bedtime of EG4 was significantly later than that of the EG1 or EG3. Wake-up time in the EG4 was significantly later than that of the EG1 or the EG3. Sleep onset latency in the EG4 was longer than that of the EG3. The quality of sleep in the EG4 was lower than that of the EG3. Sleep cycle in the EG4 was significantly shorter than that of the EG1. Blood melatonin concentrations of the EG3 was significantly higher than that of the EG4. There were no significant differences in blood concentrations of cortisol, epinephrine, or norepinephrine among protocols, with the order from the lowest to the highest values of EG1 < EG2 < EG3 < EG4. [Conclusion] The present data found that EG1 and EG3 showed positive sleep-related hormonal responses, sleep habits, and quality of sleep, indicating that sun exposure or exercise with sun exposure may improve the physical status and quality of life. PMID:25566466

Effect of working consecutive night shifts on sleep time, prior wakefulness, perceived levels of fatigue and performance on a psychometric test in emergency registrars.

PubMed

Haire, Julia Christine Lydia; Ferguson, Sally Anne; Tilleard, James D; Negus, Paul; Dorrian, Jillian; Thomas, Matthew Jw

2012-06-01

To evaluate the effect of working consecutive night shifts on sleep time, prior wakefulness, perceived levels of fatigue and psychomotor performance in a group of Australian emergency registrars. A prospective observational study with a repeated within-subjects component was conducted. Sleep time was determined using sleep diaries and activity monitors. Subjective fatigue levels and reciprocal reaction times were evaluated before and after day and night shifts. A total of 11 registrars participated in the study with 120 shifts analysed. Sleep time was found to be similar during consecutive night and day shifts. The mean number of hours spent awake before the end of a night shift was 14.33. Subjective fatigue scores were worst at the end of a night shift. There was no difference in reciprocal reaction time between the end of night shift and the start of day shift. Registrars sleep a similar amount of time surrounding night and day shifts. Despite reporting the highest levels of fatigue at the end of a night shift, there is no significant difference in reaction times at the end of night shift compared with the beginning of day shift. This correlates with the finding that at the end of night shift the registrars have been awake for less than 16 h, which is the point at which psychomotor performance is expected to decline. © 2012 The Authors. EMA © 2012 Australasian College for Emergency Medicine and Australasian Society for Emergency Medicine.

No objectively measured sleep disturbances in children with attention-deficit/hyperactivity disorder.

PubMed

Bergwerff, Catharina E; Luman, Marjolein; Oosterlaan, Jaap

2016-10-01

The main goal of this study was to gain more insight into sleep disturbances in children with attention-deficit/hyperactivity disorder, using objective measures of sleep quality and quantity. The evidence for sleep problems in children with attention-deficit/hyperactivity disorder thus far is inconsistent, which might be explained by confounding influences of comorbid internalizing and externalizing problems and low socio-economic status. We therefore investigated the mediating and moderating role of these factors in the association between attention-deficit/hyperactivity disorder and sleep problems. To control for the effects of stimulant medication use, all participants were tested free of medication. Sixty-three children with attention-deficit/hyperactivity disorder and 61 typically developing children, aged 6-13 years, participated. Sleep was monitored for one to three school nights using actigraphy. Parent and teacher questionnaires assessed symptoms of attention-deficit/hyperactivity disorder, internalizing behaviour, oppositional defiant disorder and conduct disorder. Results showed no differences between the attention-deficit/hyperactivity disorder and typically developing group in any sleep parameter. Within the attention-deficit/hyperactivity disorder group, severity of attention-deficit/hyperactivity disorder symptoms was not related to sleep quality or quantity. Moderation analyses in the attention-deficit/hyperactivity disorder group showed an interaction effect between attention-deficit/hyperactivity disorder symptoms and internalizing and externalizing behaviour on total sleep time, time in bed and average sleep bout duration. The results of our study suggest that having attention-deficit/hyperactivity disorder is not a risk factor for sleep problems. Internalizing and externalizing behaviour moderate the association between attention-deficit/hyperactivity disorder and sleep, indicating a complex interplay between psychiatric symptoms and sleep. © 2016 European Sleep Research Society.

Recovery of neurological function despite immediate sleep disruption following diffuse brain injury in the mouse: clinical relevance to medically untreated concussion.

PubMed

Rowe, Rachel K; Harrison, Jordan L; O'Hara, Bruce F; Lifshitz, Jonathan

2014-04-01

We investigated the relationship between immediate disruption of posttraumatic sleep and functional outcome in the diffuse brain-injured mouse. Adult male C57BL/6 mice were subjected to moderate midline fluid percussion injury (n = 65; 1.4 atm; 6-10 min righting reflex time) or sham injury (n = 44). Cohorts received either intentional sleep disruption (minimally stressful gentle handling) or no sleep disruption for 6 h following injury. Following disruption, serum corticosterone levels (enzyme-linked immunosorbent assay) and posttraumatic sleep (noninvasive piezoelectric sleep cages) were measured. For 1-7 days postinjury, sensorimotor outcome was assessed by Rotarod and a modified Neurological Severity Score (NSS). Cognitive function was measured using Novel Object Recognition (NOR) and Morris water maze (MWM) in the first week postinjury. Neurotrauma research laboratory. Disrupting posttraumatic sleep for 6 h did not affect serum corticosterone levels or functional outcome. In the hour following the first dark onset, sleep-disrupted mice exhibited a significant increase in sleep; however, this increase was not sustained and there was no rebound of lost sleep. Regardless of sleep disruption, mice showed a time-dependent improvement in Rotarod performance, with brain-injured mice having significantly shorter latencies on day 7 compared to sham. Further, brain-injured mice, regardless of sleep disruption, had significantly higher NSS scores postinjury compared with sham. Cognitive behavioral testing showed no group differences among any treatment group measured by MWM and NOR. Short-duration disruption of posttraumatic sleep did not affect functional outcome, measured by motor and cognitive performance. These data raise uncertainty about posttraumatic sleep as a mechanism of recovery from diffuse brain injury.

Chronotype, bed timing and total sleep time in seniors

PubMed Central

Monk, Timothy H.; Buysse, Daniel J.

2014-01-01

Many older adults (seniors) experience problems with getting enough sleep. Because of the link between sleep and circadian rhythms, changes in bedtime lead to changes in the amount of sleep obtained. Although primarily determined genetically, chronotype changes with advancing age towards a more morning-type (M-type) orientation. In a 2006 study, we have found a linear relationship, by which the earlier a senior’s bedtime, the more sleep she/he will obtain. The aim of this study was to see whether this relationship differs for M-type seniors, as compared to seniors outside the M-type category. Retired seniors (n = 954, 535 M, 410F, 65 years+, mean age 74.4 years) taking part in a telephone interview were divided into M-types and Other types (O-types) using the Composite Scale of Morningness (CSM). The relationship between bedtime and Total Sleep Time (TST), and between rise-time and TST, was tested using linear regression separately for M-types and O-types. For each participant, habitual bedtime, rise-time and total Sleep Time (TST) [after removing time spent in unwanted wakefulness] were obtained using a telephone version of the Sleep Timing Questionnaire (STQ). Both chronotype groups showed a significant linear relationship between bedtime and TST (p<0.001); with earlier bedtimes leading to more TST (M-type 5.6 min; O-type 4.4 min per 10 min change [slope difference p = 0.05]); and an opposite relationship between rise-time and TST with earlier rise-times leading to less TST (M-type 6.7 min; O-type 4.2 min per 10 min change [slope difference p 0.001]). M-types retired to bed 56 min earlier (p<0.001), awoke 93 min earlier (p<0.001) and obtained 23 min less TST (p<0.001) than O-types. In conclusion, both chronotypes showed TST to be related in a linear way to bedtime and rise-time; the overall shorter TST in M-types was due to them rising 93 min earlier, but only retiring to bed 56 min earlier than O-types; as well as having a steeper rise-time versus TST relationship. PMID:24517139

Use of a Supplementary Internet Based Education Program Improves Sleep Literacy in College Psychology Students

PubMed Central

Quan, Stuart F.; Anderson, Janis L.; Hodge, Gordon K.

2013-01-01

Introduction: Knowledge regarding the importance of sleep in health and performance and good sleep hygiene practices is low, especially among adolescents and young adults. It is important to improve sleep literacy. Introductory psychology is one of the most highly enrolled courses at colleges and universities. This study tested the impact of an Internet-based learning module on improving sleep literacy in this venue. Methods: An Internet-based supplementary learning module containing sleep physiology and hygiene information was developed using content from the Harvard Medical School sleep educational website http://www.understandingsleep.org. Access to the module was provided as an extra credit activity for 2 of 4 sections (Supplemental Sleep, SS, N = 889) of an introductory college psychology course during their standard instruction on sleep and dreaming. The remaining 2 sections (Standard Instruction, SI, N = 878) only were encouraged to visit the website without further direction. Level of knowledge was assessed before and after availability to the module/website and at the end of the semester. Students were asked to complete a survey at the end of the semester inquiring whether they made any changes in their sleep behaviors. Results: Two hundred fifty students participated in the extra credit activity and had data available at all testing points. Students in the SS Group had a significant improvement in sleep knowledge test scores after interacting with the website in comparison to the SI group (19.41 ± 3.15 vs. 17.94 ± 3.08, p < 0.001). This difference persisted, although at a lower level, at the end of the semester. In addition, 55.9% of the SS group versus 45.1% of the SI group indicated that they made changes in their sleep habits after participation in the extra credit sleep activity (p < 0.01). The most common change was a more consistent wake time. Conclusion: Use of a supplementary internet-based sleep learning module has the potential to enhance sleep literacy and change behavior among students enrolled in an introductory college psychology course. Citation: Quan SF; Anderson JL; Hodge GK. Use of a supplementary internet based education program improves sleep literacy in college psychology students. J Clin Sleep Med 2013;9(2):155-160. PMID:23372469

A systematic review of the sleep, sleepiness, and performance implications of limited wake shift work schedules.

PubMed

Short, Michelle A; Agostini, Alexandra; Lushington, Kurt; Dorrian, Jillian

2015-09-01

The aim of this review was to identify which limited wake shift work schedules (LWSW) best promote sleep, alertness, and performance. LWSW are fixed work/rest cycles where the time-at-work does is ≤8 hours and there is >1 rest period per day, on average, for ≥2 consecutive days. These schedules are commonly used in safety-critical industries such as transport and maritime industries. Literature was sourced using PubMed, Embase, PsycInfo, Scopus, and Google Scholar databases. We identified 20 independent studies (plus a further 2 overlapping studies), including 5 laboratory and 17 field-based studies focused on maritime watch keepers, ship bridge officers, and long-haul train drivers. The measurement of outcome measures was varied, incorporating subjective and objective measures of sleep: sleep diaries (N=5), actigraphy (N=4), and polysomnography, (N=3); sleepiness: Karolinska Sleepiness Scale (N=5), visual analog scale (VAS) alertness (N=2) and author-derived measures (N=2); and performance: Psychomotor Vigilance Test (PVT) (N=5), Reaction Time or Vigilance tasks (N=4), Vector and Letter Cancellation Test (N=1), and subjective performance (N=2). Of the three primary rosters examined (6 hours-on/6 hours-off, 8 hours-on/8 hours-off and 4 hours-on/8 hours-off), the 4 hours-on/8 hours-off roster was associated with better sleep and lower levels of sleepiness. Individuals working 4 hours-on/8 hours-off rosters averaged 1 hour more sleep per night than those working 6 hours-on/6 hours-off and 1.3 hours more sleep than those working 8 hours-on/8 hours-off (P<0.01). More broadly, findings indicate that LWSW schedules were associated with better sleep and lower sleepines in the case of (i) shorter time-at-work, (ii) more frequent rest breaks, (iii) shifts that start and end at the same clock time every 24 hours, and (iv) work shifts commencing in the daytime (as opposed to night). The findings for performance remain incomplete due to the small number of studies containing a performance measure and the heterogeneity of performance measures within those that did. The literature supports the utility of LWSW in industries where individuals sleep at or near the workplace as they facilitate at least some sleep during the biological night and minimize deficits associated with time-on-shift with shorter shifts. Overall, the 4 hour-on/8 hour-off roster best promoted sleep and minimized sleepiness compared to other LWSW schedules. Nevertheless, and considering the safety-critical nature of industries which employ LWSW, the limited literature needs to be greatly expanded with specific focus on the consequences for performance and comparison to mainstream rosters.

Classification of iRBD and Parkinson's disease patients based on eye movements during sleep.

PubMed

Christensen, Julie A E; Koch, Henriette; Frandsen, Rune; Kempfner, Jacob; Arvastson, Lars; Christensen, Soren R; Sorensen, Helge B D; Jennum, Poul

2013-01-01

Patients suffering from the sleep disorder idiopathic rapid-eye-movement sleep behavior disorder (iRBD) have been observed to be in high risk of developing Parkinson's disease (PD). This makes it essential to analyze them in the search for PD biomarkers. This study aims at classifying patients suffering from iRBD or PD based on features reflecting eye movements (EMs) during sleep. A Latent Dirichlet Allocation (LDA) topic model was developed based on features extracted from two electrooculographic (EOG) signals measured as parts in full night polysomnographic (PSG) recordings from ten control subjects. The trained model was tested on ten other control subjects, ten iRBD patients and ten PD patients, obtaining a EM topic mixture diagram for each subject in the test dataset. Three features were extracted from the topic mixture diagrams, reflecting "certainty", "fragmentation" and "stability" in the timely distribution of the EM topics. Using a Naive Bayes (NB) classifier and the features "certainty" and "stability" yielded the best classification result and the subjects were classified with a sensitivity of 95 %, a specificity of 80% and an accuracy of 90 %. This study demonstrates in a data-driven approach, that iRBD and PD patients may exhibit abnorm form and/or timely distribution of EMs during sleep.

Sleep Disorders in Aboriginal and Torres Strait Islander People and Residents of Regional and Remote Australia.

PubMed

Woods, Cindy E; McPherson, Karen; Tikoft, Erik; Usher, Kim; Hosseini, Fariborz; Ferns, Janine; Jersmann, Hubertus; Antic, Ral; Maguire, Graeme Paul

2015-11-15

To compare the use of sleep diagnostic tests, the risks, and cofactors, and outcomes of the care of Indigenous and non-indigenous Australian adults in regional and remote Australia in whom sleep related breathing disorders have been diagnosed. A retrospective cohort study of 200 adults; 100 Aboriginal and Torres Strait Islander and 100 non-indigenous adults with a confirmed sleep related breathing disorder diagnosed prior to September 2011 at Alice Springs Hospital and Cairns Hospital, Australia. Results showed overall Indigenous Australians were 1.8 times more likely to have a positive diagnostic sleep study performed compared with non-indigenous patients, 1.6 times less likely in central Australia and 3.4 times more likely in far north Queensland. All regional and remote residents accessed diagnostic sleep studies at a rate less than Australia overall (31/100,000/y (95% confidence interval, 21-44) compared with 575/100,000/y). The barriers to diagnosis and ongoing care are likely to relate to remote residence, lower health self-efficacy, the complex nature of the treatment tool, and environmental factors such as electricity and sleeping area. Indigeneity, remote residence, environmental factors, and low awareness of sleep health are likely to affect service accessibility and rate of use and capacity to enhance patient and family education and support following a diagnosis. A greater understanding of enablers and barriers to care and evaluation of interventions to address these are required. A commentary on this article appears in this issue on page 1255. © 2015 American Academy of Sleep Medicine.

Melatonin and bright-light treatment for rest-activity disruption in institutionalized patients with Alzheimer's disease.

PubMed

Dowling, Glenna A; Burr, Robert L; Van Someren, Eus J W; Hubbard, Erin M; Luxenberg, Jay S; Mastick, Judy; Cooper, Bruce A

2008-02-01

To test whether the addition of melatonin to bright-light therapy enhances the efficacy in treating rest-activity (circadian) disruption in institutionalized patients with Alzheimer's disease (AD). Randomized, controlled trial. Two nursing homes in San Francisco, California. Fifty subjects (mean age 86) with AD. Experimental subjects received 1 hour of morning light exposure (> or = 2,500 lux in gaze direction) Monday to Friday for 10 weeks and 5 mg melatonin (LM, n=16) or placebo (LP, n=17) in the evening. Control subjects (n=17) received usual indoor light (150-200 lux). Nighttime sleep variables, day sleep time, day activity, day:night sleep ratio, and rest-activity parameters were determined using actigraphy. Linear mixed models were employed to test the primary study hypotheses. No significant differences in nighttime sleep variables were found between groups. At the end of the intervention, the LM group showed significant improvement in daytime somnolence as indicated by a reduction in the duration of daytime sleep, an increase in daytime activity, and an improvement in day:night sleep ratio. The LM group also evidenced a significant increase in rest-activity rhythm amplitude and goodness of fit to the cosinor model. Light treatment alone did not improve nighttime sleep, daytime wake, or rest-activity rhythm. Light treatment plus melatonin increased daytime wake time and activity levels and strengthened the rest-activity rhythm. Future studies should resolve the question of whether these improvements can be attributed to melatonin or whether the two zeitgebers interact to amplify efficacy.

Melatonin and Bright-Light Treatment for Rest–Activity Disruption in Institutionalized Patients with Alzheimer’s Disease

PubMed Central

Dowling, Glenna A.; Burr, Robert L.; Van Someren, Eus J. W.; Hubbard, Erin M.; Luxenberg, Jay S.; Mastick, Judy; Cooper, Bruce A.

2008-01-01

OBJECTIVES To test whether the addition of melatonin to bright-light therapy enhances the efficacy in treating rest–activity (circadian) disruption in institutionalized patients with Alzheimer’s disease (AD). DESIGN Randomized, controlled trial. SETTING Two nursing homes in San Francisco, California. PARTICIPANTS Fifty subjects (mean age 86) with AD. INTERVENTION Experimental subjects received 1 hour of morning light exposure (≥2,500 lux in gaze direction) Monday to Friday for 10 weeks and 5 mg melatonin (LM, n = 16) or placebo (LP, n = 17) in the evening. Control subjects (n = 17) received usual indoor light (150–200 lux). MEASUREMENTS Nighttime sleep variables, day sleep time, day activity, day:night sleep ratio, and rest–activity parameters were determined using actigraphy. RESULTS Linear mixed models were employed to test the primary study hypotheses. No significant differences in nighttime sleep variables were found between groups. At the end of the intervention, the LM group showed significant improvement in daytime somnolence as indicated by a reduction in the duration of daytime sleep, an increase in daytime activity, and an improvement in day:night sleep ratio. The LM group also evidenced a significant increase in rest–activity rhythm amplitude and goodness of fit to the cosinor model. CONCLUSION Light treatment alone did not improve nighttime sleep, daytime wake, or rest–activity rhythm. Light treatment plus melatonin increased daytime wake time and activity levels and strengthened the rest–activity rhythm. Future studies should resolve the question of whether these improvements can be attributed to melatonin or whether the two zeitgebers interact to amplify efficacy. PMID:18070004

Dormitory of Physical and Engineering Sciences: Sleeping Beauties May Be Sleeping Innovations.

PubMed

van Raan, Anthony F J

2015-01-01

A 'Sleeping Beauty in Science' is a publication that goes unnoticed ('sleeps') for a long time and then, almost suddenly, attracts a lot of attention ('is awakened by a prince'). The aim of this paper is to present a general methodology to investigate (1) important properties of Sleeping Beauties such as the time-dependent distribution, author characteristics, journals and fields, and (2) the cognitive environment of Sleeping Beauties. We are particularly interested to find out to what extent Sleeping Beauties are application-oriented and thus are potential Sleeping Innovations. In this study we focus primarily on physics (including materials science and astrophysics) and present first results for chemistry and for engineering & computer science. We find that more than half of the SBs are application-oriented. To study the cognitive environments of Sleeping Beauties we develop a new approach in which the cognitive environment of the SBs is analyzed, based on the mapping of Sleeping Beauties using their citation links and conceptual relations, particularly co-citation mapping. In this way we investigate the research themes in which the SBs are 'used' and possible causes of why the premature work in the SBs becomes topical, i.e., the trigger of the awakening of the SBs. This approach is tested with a blue skies SB and an application-oriented SB. We think that the mapping procedures discussed in this paper are not only important for bibliometric analyses. They also provide researchers with useful, interactive tools to discover both relevant older work as well as new developments, for instance in themes related to Sleeping Beauties that are also Sleeping Innovations.

Repeated dose comparison of nomifensine, imipramine and placebo on subjective assessments of sleep and objective measures of psychomotor performance

PubMed Central

Hindmarch, I.; Parrott, A. C.

1977-01-01

1 Nine normal subjects volunteered to participate in a randomized single-blind crossover study of nomifensine 75 mg and two comparators, imipramine 75 mg and placebo. 2 Each volunteer received placebo for 3 d, then the first test drug for 4 days. This sequence was repeated twice more, so that each subject received each comparator. All medication was taken three times daily. 3 Assessments were made on days 3, 5 and 7 of each sequence, and consisted of a Sleep Evaluation Questionnaire, a test of Critical Flicker Fusion and a measurement of Complex Reaction Time (CRT). 4 There were no significant differences in the CRT. There was a significant increase in critical flicker fusion with nomifensine. 5 Although both nomifensine and imipramine disturbed the quality of sleep, only imipramine produced a hangover. PMID:334219

Impairment due to combined sleep restriction and alcohol is not mitigated by decaying breath alcohol concentration or rest breaks.

PubMed

Manousakis, Jessica E; Anderson, Clare

2017-09-01

Epidemiological and laboratory-based driving simulator studies have shown the detrimental impact of moderate, legal levels of alcohol consumption on driving performance in sleepy drivers. As less is known about the time course of decaying alcohol alongside performance impairment, our study examined impairment and recovery of performance alongside decaying levels of alcohol, with and without sleep restriction. Sixteen healthy young males (18-27 years) underwent 4 counterbalanced conditions: Baseline, Alcohol (breath alcohol concentration [BrAC] < 0.05%), Sleep Restriction (5 hr time in bed), and Combined. Participants consumed alcohol (or control drink) ~4.5 hr post wake (12:30 p.m.). To test on the descending limb of alcohol, attention and vigilance test batteries commenced 1 hr after consumption and were completed every 30 min for 2 hr (1:30 p.m.-3:30 p.m.). The Combined condition impaired subjective and objective sleepiness. Here, performance deficits peaked 90 min after alcohol consumption or 30 min after the BrAC peak. Performance did not return to baseline levels until 2.5 hr following consumption, despite receiving rest breaks in between testing. These findings suggest that (a) falling BrACs are an inadequate guide for performance/safety and (b) rest breaks without sleep are not a safety measure for mitigating performance impairment when consuming alcohol following restricted sleep. Copyright © 2017 John Wiley & Sons, Ltd.

Lithium prevents REM sleep deprivation-induced impairments on memory consolidation.

PubMed

Ota, Simone M; Moreira, Karin Di Monteiro; Suchecki, Deborah; Oliveira, Maria Gabriela M; Tiba, Paula A

2013-11-01

Pre-training rapid eye movement sleep (REMS) deprivation affects memory acquisition and/or consolidation. It also produces major REMS rebound at the cost of waking and slow wave sleep (SWS). Given that both SWS and REMS appear to be important for memory processes, REMS rebound after training may disrupt the organization of sleep cycles, i.e., excessive amount of REMS and/or little SWS after training could be harmful for memory formation. To examine whether lithium, a drug known to increase SWS and reduce REMS, could prevent the memory impairment induced by pre-training sleep deprivation. Animals were divided in 2 groups: cage control (CC) and REMS-deprived (REMSDep), and then subdivided into 4 subgroups, treated either with vehicle or 1 of 3 doses of lithium (50, 100, and 150 mg/kg) 2 h before training on the multiple trial inhibitory avoidance task. Animals were tested 48 h later to make sure that the drug had been already metabolized and eliminated. Another set of animals was implanted with electrodes and submitted to the same experimental protocol for assessment of drug-induced sleep-wake changes. Wistar male rats weighing 300-400 g. Sleep deprived rats required more trials to learn the task and still showed a performance deficit during test, except from those treated with 150 mg/kg of lithium, which also reduced the time spent in REM sleep during sleep recovery. Lithium reduced rapid eye movement sleep and prevented memory impairment induced by sleep deprivation. These results indicate that these phenomena may be related, but cause-effect relationship cannot be ascertained.

Scheduled Evening Sleep and Enhanced Lighting Improve Adaptation to Night Shift Work in Older Adults

PubMed Central

Chinoy, Evan D.; Harris, Michael P.; Kim, Min Ju; Wang, Wei; Duffy, Jeanne F.

2017-01-01

Objectives We tested whether a sleep and circadian-based treatment shown to improve circadian adaptation to night shifts and attenuate negative effects on alertness, performance, and sleep in young adults would also be effective in older adults. Methods We assessed subjective alertness, sustained attention (psychomotor vigilance task, PVT), sleep duration (actigraphy), and circadian timing (salivary dim-light melatonin onset, DLMO) in eighteen older adults (57.2±3.8 y; mean±SD) in a simulated shift work protocol. Four day shifts were followed by three night shifts in the laboratory. Participants slept at home and were randomized to either the Treatment Group (scheduled evening sleep and enhanced lighting during the latter half of night shifts), or Control Group (ad lib sleep and typical lighting during night shifts). Results Compared to day shifts, alertness and sustained attention declined on the first night shift in both groups, and was worse in the latter half of the night shifts. Alertness and attention improved on nights 2 and 3 for the Treatment Group but remained lower for the Control Group. Sleep duration in the Treatment Group remained similar to baseline (6–7 h) following night shifts, but was shorter (3–5 h) following night shifts in the Control Group. Treatment Group circadian timing advanced by 169.3±16.1 min (mean±SEM) but did not shift (−9.7±9.9 min) in the Control Group. Conclusions The combined treatment of scheduled evening sleep and enhanced lighting increased sleep duration and partially aligned circadian phase with sleep and work timing, resulting in improved night shift alertness and performance. PMID:27566781

Survey and comparison of sleep quality among fixed and changing shift staff in a steel factory in Tehran, Iran.

PubMed

Mohammadian, Farugh; Abbasinia, Marzieh; Rahmani, Abdolrasoul; Monazzam, Mohammad Reza; Asghari, Mehdi; Ahmadnezhad, Iman; Asadi, Ali

2013-01-01

Given the hazardous nature of the work in steel factories and that the staff has to deal with hazardous equipment and machines, improper sleep quality and drowsiness among the works tackles performance and boosts rate of job accidents. This study is aimed to survey the quality of sleep and sleepiness status and the pertinent factors among the workers in a rolling mill and a steel production company in Tehran, Iran. In a Cross-Sectional study 2011, 180 workers were selected randomly from a rolling mill and a steel production company in Tehran. A questionnaire was designed to collect demographic data and variables of work condition. Pitersborg's sleep quality questionnaire was used to survey quality and problems of Participants' sleep. Epworth Sleepiness questionnaire was used to deals with sleepiness during work, studying, watching TV, or during time spent in public. Average score of sleep quality for the fixed shift staff and changing shift staff were 7.5±2.82 and 8.49±2.95 respectively. Surveys of sleep quality for the two groups of the participants based on T-test showed a significant difference between the two groups so that the changing shift staff group suffered poorer sleep quality (p=0.03). Comparison of average drowsiness scores between the two groups of participants based on Mann-Whitney test showed no significant difference (p>0.005). Chi square test showed a significant difference between severity of drowsiness and type of working shift (p =0.028 and 0.009). Staff in revolving shifts suffers poor sleep quality comparing with staff with fixed working shift. Moreover, type of working shift greatly affects severity of drowsiness as staff at different work shift experienced different level of sleepiness. It is essential to survey sleep disorder of the staff in the industry and pay more emphasis on sleep disorder epidemic in other fields of industry.

Modulation of Total Sleep Time by Transcranial Direct Current Stimulation (tDCS).

PubMed

Frase, Lukas; Piosczyk, Hannah; Zittel, Sulamith; Jahn, Friederike; Selhausen, Peter; Krone, Lukas; Feige, Bernd; Mainberger, Florian; Maier, Jonathan G; Kuhn, Marion; Klöppel, Stefan; Normann, Claus; Sterr, Annette; Spiegelhalder, Kai; Riemann, Dieter; Nitsche, Michael A; Nissen, Christoph

2016-09-01

Arousal and sleep are fundamental physiological processes, and their modulation is of high clinical significance. This study tested the hypothesis that total sleep time (TST) in humans can be modulated by the non-invasive brain stimulation technique transcranial direct current stimulation (tDCS) targeting a 'top-down' cortico-thalamic pathway of sleep-wake regulation. Nineteen healthy participants underwent a within-subject, repeated-measures protocol across five nights in the sleep laboratory with polysomnographic monitoring (adaptation, baseline, three experimental nights). tDCS was delivered via bi-frontal target electrodes and bi-parietal return electrodes before sleep (anodal 'activation', cathodal 'deactivation', and sham stimulation). Bi-frontal anodal stimulation significantly decreased TST, compared with cathodal and sham stimulation. This effect was location specific. Bi-frontal cathodal stimulation did not significantly increase TST, potentially due to ceiling effects in good sleepers. Exploratory resting-state EEG analyses before and after the tDCS protocols were consistent with the notion of increased cortical arousal after anodal stimulation and decreased cortical arousal after cathodal stimulation. The study provides proof-of-concept that TST can be decreased by non-invasive bi-frontal anodal tDCS in healthy humans. Further elucidating the 'top-down' pathway of sleep-wake regulation is expected to increase knowledge on the fundamentals of sleep-wake regulation and to contribute to the development of novel treatments for clinical conditions of disturbed arousal and sleep.

Circadian factor BMAL1 in histaminergic neurons regulates sleep architecture.

PubMed

Yu, Xiao; Zecharia, Anna; Zhang, Zhe; Yang, Qianzi; Yustos, Raquel; Jager, Polona; Vyssotski, Alexei L; Maywood, Elizabeth S; Chesham, Johanna E; Ma, Ying; Brickley, Stephen G; Hastings, Michael H; Franks, Nicholas P; Wisden, William

2014-12-01

Circadian clocks allow anticipation of daily environmental changes. The suprachiasmatic nucleus (SCN) houses the master clock, but clocks are also widely expressed elsewhere in the body. Although some peripheral clocks have established roles, it is unclear what local brain clocks do. We tested the contribution of one putative local clock in mouse histaminergic neurons in the tuberomamillary nucleus to the regulation of the sleep-wake cycle. Histaminergic neurons are silent during sleep, and start firing after wake onset; the released histamine, made by the enzyme histidine decarboxylase (HDC), enhances wakefulness. We found that hdc gene expression varies with time of day. Selectively deleting the Bmal1 (also known as Arntl or Mop3) clock gene from histaminergic cells removes this variation, producing higher HDC expression and brain histamine levels during the day. The consequences include more fragmented sleep, prolonged wake at night, shallower sleep depth (lower nonrapid eye movement [NREM] δ power), increased NREM-to-REM transitions, hindered recovery sleep after sleep deprivation, and impaired memory. Removing BMAL1 from histaminergic neurons does not, however, affect circadian rhythms. We propose that for mammals with polyphasic/nonwake consolidating sleep, the local BMAL1-dependent clock directs appropriately timed declines and increases in histamine biosynthesis to produce an appropriate balance of wake and sleep within the overall daily cycle of rest and activity specified by the SCN. Copyright © 2014 The Authors. Published by Elsevier Inc. All rights reserved.

Modulation of Total Sleep Time by Transcranial Direct Current Stimulation (tDCS)

PubMed Central

Frase, Lukas; Piosczyk, Hannah; Zittel, Sulamith; Jahn, Friederike; Selhausen, Peter; Krone, Lukas; Feige, Bernd; Mainberger, Florian; Maier, Jonathan G; Kuhn, Marion; Klöppel, Stefan; Normann, Claus; Sterr, Annette; Spiegelhalder, Kai; Riemann, Dieter; Nitsche, Michael A; Nissen, Christoph

2016-01-01

Arousal and sleep are fundamental physiological processes, and their modulation is of high clinical significance. This study tested the hypothesis that total sleep time (TST) in humans can be modulated by the non-invasive brain stimulation technique transcranial direct current stimulation (tDCS) targeting a ‘top-down' cortico-thalamic pathway of sleep-wake regulation. Nineteen healthy participants underwent a within-subject, repeated-measures protocol across five nights in the sleep laboratory with polysomnographic monitoring (adaptation, baseline, three experimental nights). tDCS was delivered via bi-frontal target electrodes and bi-parietal return electrodes before sleep (anodal ‘activation', cathodal ‘deactivation', and sham stimulation). Bi-frontal anodal stimulation significantly decreased TST, compared with cathodal and sham stimulation. This effect was location specific. Bi-frontal cathodal stimulation did not significantly increase TST, potentially due to ceiling effects in good sleepers. Exploratory resting-state EEG analyses before and after the tDCS protocols were consistent with the notion of increased cortical arousal after anodal stimulation and decreased cortical arousal after cathodal stimulation. The study provides proof-of-concept that TST can be decreased by non-invasive bi-frontal anodal tDCS in healthy humans. Further elucidating the ‘top-down' pathway of sleep-wake regulation is expected to increase knowledge on the fundamentals of sleep-wake regulation and to contribute to the development of novel treatments for clinical conditions of disturbed arousal and sleep. PMID:27143601

Efficacy of melatonin with behavioural sleep-wake scheduling for delayed sleep-wake phase disorder: A double-blind, randomised clinical trial.

PubMed

Sletten, Tracey L; Magee, Michelle; Murray, Jade M; Gordon, Christopher J; Lovato, Nicole; Kennaway, David J; Gwini, Stella M; Bartlett, Delwyn J; Lockley, Steven W; Lack, Leon C; Grunstein, Ronald R; Rajaratnam, Shantha M W

2018-06-01

Delayed Sleep-Wake Phase Disorder (DSWPD) is characterised by sleep initiation insomnia when attempting sleep at conventional times and difficulty waking at the required time for daytime commitments. Although there are published therapeutic guidelines for the administration of melatonin for DSWPD, to our knowledge, randomised controlled trials are lacking. This trial tested the efficacy of 0.5 mg melatonin, combined with behavioural sleep-wake scheduling, for improving sleep initiation in clinically diagnosed DSWPD patients with a delayed endogenous melatonin rhythm relative to patient-desired (or -required) bedtime (DBT). This randomised, placebo-controlled, double-blind clinical trial was conducted in an Australian outpatient DSWPD population. Following 1-wk baseline, clinically diagnosed DSWPD patients with delayed melatonin rhythm relative to DBT (salivary dim light melatonin onset [DLMO] after or within 30 min before DBT) were randomised to 4-wk treatment with 0.5 mg fast-release melatonin or placebo 1 h before DBT for at least 5 consecutive nights per week. All patients received behavioural sleep-wake scheduling, consisting of bedtime scheduled at DBT. The primary outcome was actigraphic sleep onset time. Secondary outcomes were sleep efficiency in the first third of time in bed (SE T1) on treatment nights, subjective sleep-related daytime impairment (Patient Reported Outcomes Measurement Information System [PROMIS]), PROMIS sleep disturbance, measures of daytime sleepiness, clinician-rated change in illness severity, and DLMO time. Between September 13, 2012 and September 1, 2014, 307 participants were registered; 116 were randomised to treatment (intention-to-treat n = 116; n = 62 males; mean age, 29.0 y). Relative to baseline and compared to placebo, sleep onset occurred 34 min earlier (95% confidence interval [CI] -60 to -8) in the melatonin group. SE T1 increased; PROMIS sleep-related impairment, PROMIS sleep disturbance, insomnia severity, and functional disability decreased; and a greater proportion of patients showed more than minimal clinician-rated improvement following melatonin treatment (52.8%) compared to placebo (24.0%) (P < 0.05). The groups did not differ in the number of nights treatment was taken per protocol. Post-treatment DLMO assessed in a subset of patients (n = 43) was not significantly different between groups. Adverse events included light-headedness, daytime sleepiness, and decreased libido, although rates were similar between treatment groups. The clinical benefits or safety of melatonin with long-term treatment were not assessed, and it remains unknown whether the same treatment regime would benefit patients experiencing DSWPD sleep symptomology without a delay in the endogenous melatonin rhythm. In this study, melatonin treatment 1 h prior to DBT combined with behavioural sleep-wake scheduling was efficacious for improving objective and subjective measures of sleep disturbances and sleep-related impairments in DSWPD patients with delayed circadian phase relative to DBT. Improvements were achieved largely through the sleep-promoting effects of melatonin, combined with behavioural sleep-wake scheduling. This trial was registered with the Australian New Zealand Clinical Trials Registry, ACTRN12612000425897.

Agreement between Results of Home Sleep Testing for Obstructive Sleep Apnea with and without a Sleep Specialist

PubMed Central

Aurora, R. Nisha; Putcha, Nirupama; Swartz, Rachel; Punjabi, Naresh M.

2016-01-01

Background Obstructive sleep apnea is a prevalent yet underdiagnosed condition associated with cardiovascular morbidity and mortality. Home sleep testing offers an efficient means for diagnosing obstructive sleep apnea but has primarily been deployed in clinical samples with a high pretest probability. The current study sought to assess if obstructive sleep apnea can be diagnosed with home sleep testing in a non-referred sample without involvement of a sleep medicine specialist. Methods A study of community-based adults with untreated obstructive sleep apnea was undertaken. Misclassification of disease severity based on home sleep testing with and without involvement of a sleep medicine specialist was assessed, and agreement was characterized using scatter plots, Pearson's correlation coefficient, Bland-Altman analysis, and the kappa statistic. Analyses were also conducted to assess whether any observed differences varied as a function of pretest probability of obstructive sleep apnea or subjective sleepiness. Results The sample consisted of 191 subjects with over half (56.5%) having obstructive sleep apnea. Without involvement of a sleep medicine specialist, obstructive sleep apnea was not identified in only 5.8% of the sample. Analyses comparing the categorical assessment of disease severity with and without a sleep medicine specialist showed that in total, 32 subjects (16.8%) were misclassified. Agreement in the disease severity with and without a sleep medicine specialist was not influenced by the pretest probability or daytime sleep tendency. Conclusion Obstructive sleep apnea can be reliably identified with home sleep testing in a non-referred sample irrespective of the pretest probability of the disease. PMID:26968467

Agreement Between Results of Home Sleep Testing for Obstructive Sleep Apnea with and Without a Sleep Specialist.

PubMed

Aurora, R Nisha; Putcha, Nirupama; Swartz, Rachel; Punjabi, Naresh M

2016-07-01

Obstructive sleep apnea is a prevalent yet underdiagnosed condition associated with cardiovascular morbidity and mortality. Home sleep testing offers an efficient means for diagnosing obstructive sleep apnea but has been deployed primarily in clinical samples with a high pretest probability. The present study sought to assess whether obstructive sleep apnea can be diagnosed with home sleep testing in a nonreferred sample without involvement of a sleep medicine specialist. A study of community-based adults with untreated obstructive sleep apnea was undertaken. Misclassification of disease severity according to home sleep testing with and without involvement of a sleep medicine specialist was assessed, and agreement was characterized using scatter plots, Pearson's correlation coefficient, Bland-Altman analysis, and the κ statistic. Analyses were also conducted to assess whether any observed differences varied as a function of pretest probability of obstructive sleep apnea or subjective sleepiness. The sample consisted of 191 subjects, with more than half (56.5%) having obstructive sleep apnea. Without involvement of a sleep medicine specialist, obstructive sleep apnea was not identified in only 5.8% of the sample. Analyses comparing the categorical assessment of disease severity with and without a sleep medicine specialist showed that in total, 32 subjects (16.8%) were misclassified. Agreement in the disease severity with and without a sleep medicine specialist was not influenced by the pretest probability or daytime sleep tendency. Obstructive sleep apnea can be reliably identified with home sleep testing in a nonreferred sample, irrespective of the pretest probability of the disease. Copyright © 2016 Elsevier Inc. All rights reserved.

Anxiolytic-like effect of 2-(4-((1-phenyl-1H-pyrazol-4-yl)methyl)piperazin-1-yl)ethan-1-ol is mediated through the benzodiazepine and nicotinic pathways.

PubMed

Brito, Adriane F; Fajemiroye, James O; Neri, Hiasmin F S; Silva, Dayane M; Silva, Daiany P B; Sanz, Germán; Vaz, Boniek G; de Carvalho, Flávio S; Ghedini, Paulo C; Lião, Luciano M; Menegatti, Ricardo; Costa, Elson A

2017-09-01

In this study, we proposed the design, synthesis of a new compound 2-(4-((1-phenyl-1H-pyrazol-4-yl)methyl)piperazin-1-yl)ethan-1-ol (LQFM032), and pharmacological evaluation of its anxiolytic-like effect. This new compound was subjected to pharmacological screening referred to as Irwin test, prior to sodium pentobarbital-induced sleep, open-field and wire tests. The anxiolytic-like effect of this compound was evaluated using elevated plus maze and light-dark box tests. In addition, the mnemonic activity was evaluated through step-down test. In sodium pentobarbital-induced sleep test, LQFM032 decreased latency and increased duration of sleep. In the open-field test, LQFM032 altered behavioral parameter, that suggested anxiolytic-like activity, as increased in crossings and time spent at the center of open field. In the plus maze test and light-dark box test, the LQFM032 showed anxiolytic-like activity, increased entries and time spent on open arms, and increased in number of transitions and time spent on light area, respectively. Those effects was antagonized by flumazenil but not with 1-(2-Methoxyphenyl)-4-(4-phthalimidobutyl)piperazine (NAN-190). The LQFM032 did not alter mnemonic activity. Moreover, the anxiolytic-like activity of LQFM032 was antagonized by mecamylamine. In summary, LQFM032 showed benzodiazepine and nicotinic pathways mediated anxiolytic-like activity without altering the mnemonic activity. © 2017 John Wiley & Sons A/S.

Terror and bliss? Commonalities and distinctions between sleep paralysis, lucid dreaming, and their associations with waking life experiences.

PubMed

Denis, Dan; Poerio, Giulia L

2017-02-01

Sleep paralysis and lucid dreaming are both dissociated experiences related to rapid eye movement (REM) sleep. Anecdotal evidence suggests that episodes of sleep paralysis and lucid dreaming are related but different experiences. In this study we test this claim systematically for the first time in an online survey with 1928 participants (age range: 18-82 years; 53% female). Confirming anecdotal evidence, sleep paralysis and lucid dreaming frequency were related positively and this association was most apparent between lucid dreaming and sleep paralysis episodes featuring vestibular-motor hallucinations. Dissociative experiences were the only common (positive) predictor of both sleep paralysis and lucid dreaming. Both experiences showed different associations with other key variables of interest: sleep paralysis was predicted by sleep quality, anxiety and life stress, whereas lucid dreaming was predicted by a positive constructive daydreaming style and vividness of sensory imagery. Overall, results suggest that dissociative experiences during wakefulness are reflected in dissociative experiences during REM sleep; while sleep paralysis is related primarily to issues of sleep quality and wellbeing, lucid dreaming may reflect a continuation of greater imaginative capacity and positive imagery in waking states. © 2016 The Authors. Journal of Sleep Research published by John Wiley & Sons Ltd on behalf of European Sleep Research Society.

Why might poor sleep quality lead to depression? A role for emotion regulation.

PubMed

O'Leary, Kimberly; Bylsma, Lauren M; Rottenberg, Jonathan

2017-12-01

Disordered sleep is strongly linked to future depression, but the reasons for this link are not well understood. This study tested one possibility - that poorer sleep impairs emotion regulation (ER), which over time leads to increased depressive symptoms. Our sample contained individuals with a wide range of depression symptoms (current depression, N = 54, remitted depression, N = 36, and healthy control, N = 53), who were followed clinically over six months and reassessed for changes in depressive symptom levels. As predicted, maladaptive ER mediated both cross-sectional and prospective relationships between poor sleep quality and depression symptoms. In contrast, an alternative mediator, physical activity levels, did not mediate the link between sleep quality and depression symptoms. Maladaptive ER may help explain why sleep difficulties contribute to depression symptoms; implications for interventions are discussed.

Work routines moderate the association between eveningness and poor psychological well-being

PubMed Central

de Souza, Camila Morelatto; Hidalgo, Maria Paz Loayza

2018-01-01

Well-being is a useful screening method for the detection of mood disorders. Evidence associating psychological well-being with sleep-wake patterns exists, as well as associations with sleep-wake patterns, work-related parameters, and perceived self-efficacy. Despite the growing research regarding the relationship between these factors and mental health, there are few studies that analyze them together. OBJECTIVE: To investigate if the association between sleep-wake patterns and psychological well-being is mediated or moderated by perceived self-efficacy, work flexibility and work routines. MATERIAL AND METHODS: This cohort study was performed in southern Brazil. A sample of 987 individuals was analyzed (66.9% women; mean age = 43.9 years). Work routines parameters and work schedule flexibility were evaluated, most participants were farmers (46%) and most worked 7 days a week (69.1%). Munich Chronotype Questionnaire (MCTQ) was administered for evaluation of sleep-wake patterns, General Self-Efficacy Scale (GSE) for assessment the participants’ beliefs about how they coped with daily hassles, and World Health Organization Five-item Well-being Index (WHO-5) for evaluation of psychological well-being levels. Moderation and mediation models were tested. RESULTS: The moderation model showed influences of work end time on the relationship between sleep onset time and psychological well-being (R2 = 0.147; F = 24.16; p<0.001). The final regression model showed an association of psychological well-being with sex (Beta = -0.086; p = 0.004), sleep onset time (Beta = -0.086; p = 0.006), and self-efficacy (Beta = 0.316; p<0.001); the work end time showed association in the interaction with sleep onset time (Beta = -0.075; p = 0.016). CONCLUSION: The findings support the direct association of psychological well-being with sleep-wake patterns and self-efficacy, and show an interaction between work routines and sleep-wake patterns. Our results draw attention to the importance of the interplay between individual and social rhythms in relation to psychological well-being. PMID:29624593

Validations of a portable home sleep study with twelve-lead polysomnography: comparisons and insights into a variable gold standard.

PubMed

Michaelson, Peter G; Allan, Patrick; Chaney, John; Mair, Eric A

2006-11-01

Accurate and timely diagnosis for patients with obstructive sleep apnea (OSA) is imperative. Unfortunately, growing interest in this diagnosis has resulted in increased requests and waiting times for polysomnography (PSG), as well as a potential delay in diagnosis and treatment. This study evaluated the accuracy and viability of utilizing SNAP (SNAP Laboratories, LLC, Wheeling, Illinois), a portable home sleep test, as an alternative to traditional PSG in diagnosing OSA. This prospective clinical trial included 59 patients evaluated at our institution's sleep laboratory. Concurrent PSG and SNAP testing was performed for 1 night on each patient. Independent, blinded readers at our institution and at an outside-accredited institution read the PSG data, and 2 independent, blinded readers interpreted the SNAP data at SNAP laboratories. The apnea-hypopnea index (AHI) was used to compare the 2 testing modalities. The correlation coefficient, receiver operating characteristic curve analysis, and the Bland-Altman curves, as well as sensitivity, specificity, inter-reader variability, positive predictive value, and negative predictive value, were used to compare SNAP and PSG. There is a definitive, statistically sound correlation between the AHIs determined from both PSG and SNAP. This relationship holds true for all measures of comparison, while displaying a concerning, weaker correlation between the different PSG interpretations. There is a convincing correlation between the study-determined AHIs of both PSG and SNAP. This finding supports SNAP as a suitable alternative to PSG in identifying OSA, while accentuating the inherent variation present in a PSG-derived AHI. This test expands the diagnostic and therapeutic prowess of the practicing otolaryngologist by offering an alternative OSA testing modality that is associated with not only less expense, decreased waiting time, and increased convenience, but also statistically proven accuracy.

Endothelial function and sleep: associations of flow-mediated dilation with perceived sleep quality and rapid eye movement (REM) sleep.

PubMed

Cooper, Denise C; Ziegler, Michael G; Milic, Milos S; Ancoli-Israel, Sonia; Mills, Paul J; Loredo, José S; Von Känel, Roland; Dimsdale, Joel E

2014-02-01

Endothelial function typically precedes clinical manifestations of cardiovascular disease and provides a potential mechanism for the associations observed between cardiovascular disease and sleep quality. This study examined how subjective and objective indicators of sleep quality relate to endothelial function, as measured by brachial artery flow-mediated dilation (FMD). In a clinical research centre, 100 non-shift working adults (mean age: 36 years) completed FMD testing and the Pittsburgh Sleep Quality Index, along with a polysomnography assessment to obtain the following measures: slow wave sleep, percentage rapid eye movement (REM) sleep, REM sleep latency, total arousal index, total sleep time, wake after sleep onset, sleep efficiency and apnea-hypopnea index. Bivariate correlations and follow-up multiple regressions examined how FMD related to subjective (i.e., Pittsburgh Sleep Quality Index scores) and objective (i.e., polysomnography-derived) indicators of sleep quality. After FMD showed bivariate correlations with Pittsburgh Sleep Quality Index scores, percentage REM sleep and REM latency, further examination with separate regression models indicated that these associations remained significant after adjustments for sex, age, race, hypertension, body mass index, apnea-hypopnea index, smoking and income (Ps < 0.05). Specifically, as FMD decreased, scores on the Pittsburgh Sleep Quality Index increased (indicating decreased subjective sleep quality) and percentage REM sleep decreased, while REM sleep latency increased (Ps < 0.05). Poorer subjective sleep quality and adverse changes in REM sleep were associated with diminished vasodilation, which could link sleep disturbances to cardiovascular disease. © 2013 European Sleep Research Society.

Slow Wave Sleep Induced by GABA Agonist Tiagabine Fails to Benefit Memory Consolidation

PubMed Central

Feld, Gordon B.; Wilhelm, Ines; Ma, Ying; Groch, Sabine; Binkofski, Ferdinand; Mölle, Matthias; Born, Jan

2013-01-01

Study Objectives: Slow wave sleep (SWS) plays a pivotal role in consolidating memories. Tiagabine has been shown to increase SWS in favor of REM sleep without impacting subjective sleep. However, it is unknown whether this effect is paralleled by an improved sleep-dependent consolidation of memory. Design: This double-blind within-subject crossover study tested sensitivity of overnight retention of declarative neutral and emotional materials (word pairs, pictures) as well as a procedural memory task (sequence finger tapping) to oral administration of placebo or 10 mg tiagabine (at 22:30). Participants: Fourteen healthy young men aged 21.9 years (range 18-28 years). Measurements and Results: Tiagabine significantly increased the time spent in SWS and decreased REM sleep compared to placebo. Tiagabine also enhanced slow wave activity (0.5-4.0 Hz) and density of < 1 Hz slow oscillations during NREM sleep. Fast (12-15 Hz) and slow (9-12 Hz) spindle activity, in particular that occurring phase-locked to the slow oscillation cycle, was decreased following tiagabine. Despite signs of deeper and more SWS, overnight retention of memory tested after sleep the next evening (19:30) was generally not improved after tiagabine, but on average even lower than after placebo, with this impairing effect reaching significance for procedural sequence finger tapping. Conclusions: Our data show that increasing slow wave sleep with tiagabine does not improve memory consolidation. Possibly this is due to functional differences from normal slow wave sleep, i.e., the concurrent suppressive influence of tiagabine on phase-locked spindle activity. Citation: Feld GB; Wilhelm I; Ma Y; Groch S; Binkofski F; Mölle M; Born J. Slow wave sleep induced by GABA agonist tiagabine fails to benefit memory consolidation. SLEEP 2013;36(9):1317-1326. PMID:23997364

Mild Traumatic Brain Injury Chronically Impairs Sleep- and Wake-Dependent Emotional Processing

PubMed Central

Mantua, Janna; Henry, Owen S.; Garskovas, Nolan F.

2017-01-01

Abstract Study Objectives: A single traumatic brain injury (TBI), even when mild (ie, concussion), can cause lasting consequences. Individuals with a history of chronic (>1-year prior) mild TBI have an increased risk of mood disturbances (eg, depression, suicide). This population also has lingering sleep alterations, including poor sleep quality and changes in sleep stage proportions. Given these sleep deficits, we aimed to test whether sleep-dependent emotional memory consolidation is reduced in this population. We utilized a mild TBI group (3.7 ± 2.9 years post injury) and an uninjured (non-TBI) population. Methods: Participants viewed negative and neutral images both before and after a 12-hour period containing sleep (“Sleep” group) or an equivalent period of time spent awake (“Wake” group). Participants rated images for valence/arousal at both sessions, and memory recognition was tested at session two. Results: The TBI group had less rapid eye movement (REM), longer REM latency, and more sleep complaints. Sleep-dependent memory consolidation of nonemotional images was present in all participants. However, consolidation of negative images was only present in the non-TBI group. A lack of differentiation between the TBI Sleep and Wake groups was due to poor performance in the sleep group and, unexpectedly, enhanced performance in the wake group. Additionally, although the non-TBI participants habituated to negative images over a waking period, the TBI participants did not. Conclusions: We propose disrupted sleep- and wake-dependent emotional processing contributes to poor emotional outcomes following chronic, mild TBI. This work has broad implications, as roughly one-third of the US population will sustain a mild TBI during their lifetime. PMID:28460124

Relationship Between Reported and Measured Sleep Times

PubMed Central

Silva, Graciela E.; Goodwin, James L.; Sherrill, Duane L.; Arnold, Jean L.; Bootzin, Richard R.; Smith, Terry; Walsleben, Joyce A.; Baldwin, Carol M.; Quan, Stuart F.

2007-01-01

Study Objective: Subjective and objective assessments of sleep may be discrepant due to sleep misperception and measurement effects, the latter of which may change the quality and quantity of a person's usual sleep. This study compared sleep times from polysomnography (PSG) with self-reports of habitual sleep and sleep estimated on the morning after a PSG in adults. Design: Total sleep time and sleep onset latency obtained from unattended home PSGs were compared to sleep times obtained from a questionnaire completed before the PSG and a Morning Survey completed the morning after the PSG. Participants: A total of 2,113 subjects who were ≥ 40 years of age were included in this analysis. Measures and Results: Subjects were 53% female, 75% Caucasian, and 38% obese. The mean habitual sleep time (HABTST), morning estimated sleep time (AMTST), and PSG total sleep times (PSGTST) were 422 min, 379 min, and 363 min, respectively. The mean habitual sleep onset latency, morning estimated sleep onset latency, and PSG sleep onset latency were 17.0 min, 21.8 min, and 16.9 min, respectively. Models adjusting for related demographic factors showed that HABTST and AMTST differ significantly from PSGTST by 61 and 18 minutes, respectively. Obese and higher educated people reported less sleep time than their counterparts. Similarly, small but significant differences were seen for sleep latency. Conclusions: In a community population, self-reported total sleep times and sleep latencies are overestimated even on the morning following overnight PSG. Citation: Silva GE; Goodwin JL; Sherrill DL; Arnold JL; Bootzin RR; Smith T; Walsleben JA; Baldwin CM; Quan SF. Relationship between reported and measured sleep times: the sleep heart health study (SHHS). J Clin Sleep Med 2007;3(6):622-630. PMID:17993045

Melatonin treatment of pediatric residents for adaptation to night shift work.

PubMed

Cavallo, Anita; Ris, M Douglas; Succop, Paul; Jaskiewicz, Julie

2005-01-01

Night float rotations are used in residency training programs to reduce residents' sleep deprivation. Night shift work, however, is accompanied by deleterious effects on sleep, mood, and attention. To test whether melatonin reduces the deleterious effects of night shift work on sleep, mood, and attention in pediatric residents during night float rotation. Double-blind, randomized, placebo-controlled crossover. Participants took melatonin (3 mg) or a placebo before bedtime in the morning after night shift; completed a sleep diary and an adverse-effects questionnaire daily; and completed the Profile of Mood States and the Conners Continuous Performance Test 3 times in each study week to test mood and attention, respectively. A university-affiliated, tertiary-care pediatric hospital. Healthy second-year pediatric residents working 2 night float rotations. Standardized measures of sleep, mood, and attention. Twenty-eight residents completed both treatments; 17 completed 1 treatment (10 placebo, 7 melatonin). There was not a statistically significant difference in measures of sleep, mood, and 5 of 6 measures of attention during melatonin and placebo treatment. One measure of attention, the number of omission errors, was significantly lower on melatonin (3.0 +/- 9.6) than on placebo (4.5 +/- 17.5) (z = -2.12, P = .03). The isolated finding of improvement of 1 single measure of attention in a test situation during melatonin treatment was not sufficiently robust to demonstrate a beneficial effect of melatonin in the dose used. Other strategies need to be considered to help residents in adaptation to night shift work.

Effect of inducing nocturnal serum melatonin concentrations in daytime on sleep, mood, body temperature, and performance.

PubMed Central

Dollins, A B; Zhdanova, I V; Wurtman, R J; Lynch, H J; Deng, M H

1994-01-01

We examined effects of very low doses of melatonin (0.1-10 mg, orally) or placebo, administered at 1145 h, on sleep latency and duration, mood, performance, oral temperature, and changes in serum melatonin levels in 20 healthy male volunteers. A repeated-measure double-blind Latin square design was used. Subjects completed a battery of tests designed to assess mood and performance between 0930 and 1730 h. The sedative-like effects of melatonin were assessed by a simple sleep test: at 1330 h subjects were asked to hold a positive pressure switch in each hand and to relax with eyes closed while reclining in a quiet darkened room. Latency and duration of switch release, indicators of sleep, were measured. Areas under the time-melatonin concentration curve varied in proportion to the different melatonin doses ingested, and the 0.1- and 0.3-mg doses generated peak serum melatonin levels that were within the normal range of nocturnal melatonin levels in untreated people. All melatonin doses tested significantly increased sleep duration, as well as self-reported sleepiness and fatigue, relative to placebo. Moreover, all of the doses significantly decreased sleep-onset latency, oral temperature, and the number of correct responses on the Wilkinson auditory vigilance task. These data indicate that orally administered melatonin can be a highly potent hypnotic agent; they also suggest that the physiological increase in serum melatonin levels, which occurs around 2100 h daily, may constitute a signal initiating normal sleep onset. PMID:8127888

Effect of inducing nocturnal serum melatonin concentrations in daytime on sleep, mood, body temperature, and performance.

PubMed

Dollins, A B; Zhdanova, I V; Wurtman, R J; Lynch, H J; Deng, M H

1994-03-01

We examined effects of very low doses of melatonin (0.1-10 mg, orally) or placebo, administered at 1145 h, on sleep latency and duration, mood, performance, oral temperature, and changes in serum melatonin levels in 20 healthy male volunteers. A repeated-measure double-blind Latin square design was used. Subjects completed a battery of tests designed to assess mood and performance between 0930 and 1730 h. The sedative-like effects of melatonin were assessed by a simple sleep test: at 1330 h subjects were asked to hold a positive pressure switch in each hand and to relax with eyes closed while reclining in a quiet darkened room. Latency and duration of switch release, indicators of sleep, were measured. Areas under the time-melatonin concentration curve varied in proportion to the different melatonin doses ingested, and the 0.1- and 0.3-mg doses generated peak serum melatonin levels that were within the normal range of nocturnal melatonin levels in untreated people. All melatonin doses tested significantly increased sleep duration, as well as self-reported sleepiness and fatigue, relative to placebo. Moreover, all of the doses significantly decreased sleep-onset latency, oral temperature, and the number of correct responses on the Wilkinson auditory vigilance task. These data indicate that orally administered melatonin can be a highly potent hypnotic agent; they also suggest that the physiological increase in serum melatonin levels, which occurs around 2100 h daily, may constitute a signal initiating normal sleep onset.

Effect of inducing nocturnal serum melatonin concentrations in daytime on sleep, mood, body temperature, and performance

NASA Technical Reports Server (NTRS)

Dollins, A. B.; Zhdanova, I. V.; Wurtman, R. J.; Lynch, H. J.; Deng, M. H.

1994-01-01

We examined effects of very low doses of melatonin (0.1-10 mg, orally) or placebo, administered at 1145 h, on sleep latency and duration, mood, performance, oral temperature, and changes in serum melatonin levels in 20 healthy male volunteers. A repeated-measure double-blind Latin square design was used. Subjects completed a battery of tests designed to assess mood and performance between 0930 and 1730 h. The sedative-like effects of melatonin were assessed by a simple sleep test: at 1330 h subjects were asked to hold a positive pressure switch in each hand and to relax with eyes closed while reclining in a quiet darkened room. Latency and duration of switch release, indicators of sleep, were measured. Areas under the time-melatonin concentration curve varied in proportion to the different melatonin doses ingested, and the 0.1- and 0.3-mg doses generated peak serum melatonin levels that were within the normal range of nocturnal melatonin levels in untreated people. All melatonin doses tested significantly increased sleep duration, as well as self-reported sleepiness and fatigue, relative to placebo. Moreover, all of the doses significantly decreased sleep-onset latency, oral temperature, and the number of correct responses on the Wilkinson auditory vigilance task. These data indicate that orally administered melatonin can be a highly potent hypnotic agent; they also suggest that the physiological increase in serum melatonin levels, which occurs around 2100 h daily, may constitute a signal initiating normal sleep onset.

Sleep deprivation decreases phase-shift responses of circadian rhythms to light in the mouse: role of serotonergic and metabolic signals.

PubMed

Challet, E; Turek, F W; Laute, M; Van Reeth, O

2001-08-03

The circadian pacemaker in the suprachiasmatic nuclei is primarily synchronized to the daily light-dark cycle. The phase-shifting and synchronizing effects of light can be modulated by non-photic factors, such as behavioral, metabolic or serotonergic cues. The present experiments examine the effects of sleep deprivation on the response of the circadian pacemaker to light and test the possible involvement of serotonergic and/or metabolic cues in mediating the effects of sleep deprivation. Photic phase-shifting of the locomotor activity rhythm was analyzed in mice transferred from a light-dark cycle to constant darkness, and sleep-deprived for 8 h from Zeitgeber Time 6 to Zeitgeber Time 14. Phase-delays in response to a 10-min light pulse at Zeitgeber Time 14 were reduced by 30% in sleep-deprived mice compared to control mice, while sleep deprivation without light exposure induced no significant phase-shifts. Stimulation of serotonin neurotransmission by fluoxetine (10 mg/kg), a serotonin reuptake inhibitor that decreases light-induced phase-delays in non-deprived mice, did not further reduce light-induced phase-delays in sleep-deprived mice. Impairment of serotonin neurotransmission with p-chloroamphetamine (three injections of 10 mg/kg), which did not increase light-induced phase-delays in non-deprived mice significantly, partially normalized light-induced phase-delays in sleep-deprived mice. Injections of glucose increased light-induced phase-delays in control and sleep-deprived mice. Chemical damage of the ventromedial hypothalamus by gold-thioglucose (600 mg/kg) prevented the reduction of light-induced phase-delays in sleep-deprived mice, without altering phase-delays in control mice. Taken together, the present results indicate that sleep deprivation can reduce the light-induced phase-shifts of the mouse suprachiasmatic pacemaker, due to serotonergic and metabolic changes associated with the loss of sleep.

Cumulative Association of Obstructive Sleep Apnea Severity and Short Sleep Duration with the Risk for Hypertension

PubMed Central

Priou, Pascaline; Le Vaillant, Marc; Meslier, Nicole; Paris, Audrey; Pigeanne, Thierry; Nguyen, Xuan-Lan; Alizon, Claire; Bizieux-Thaminy, Acya; Leclair-Visonneau, Laurene; Humeau, Marie-Pierre; Gagnadoux, Frédéric

2014-01-01

Obstructive sleep apnea (OSA) and short sleep duration are individually associated with an increased risk for hypertension (HTN). The aim of this multicenter cross-sectional study was to test the hypothesis of a cumulative association of OSA severity and short sleep duration with the risk for prevalent HTN. Among 1,499 patients undergoing polysomnography for suspected OSA, 410 (27.3%) previously diagnosed as hypertensive and taking antihypertensive medication were considered as having HTN. Patients with total sleep time (TST) <6 h were considered to be short sleepers. Logistic regression procedures were performed to determine the independent association of HTN with OSA and sleep duration. Considering normal sleepers (TST ≥6 h) without OSA as the reference group, the odds ratio (OR) (95% confidence intervals) for having HTN was 2.51 (1.35–4.68) in normal sleepers with OSA and 4.37 (2.18–8.78) in short sleepers with OSA after adjustment for age, gender, obesity, diabetes, depression, current smoking, use of thyroid hormones, daytime sleepiness, poor sleep complaint, time in bed, sleep architecture and fragmentation, and study site. The risk for HTN appeared to present a cumulative association with OSA severity and short sleep duration (p<0.0001 for linear trend). The higher risk for HTN was observed in short sleepers with severe OSA (AHI ≥30) (OR, 4.29 [2.03–9.07]). In patients investigated for suspected OSA, sleep-disordered breathing severity and short sleep duration have a cumulative association with the risk for prevalent HTN. Further studies are required to determine whether interventions to optimize sleep may contribute to lower BP in patients with OSA. PMID:25531468

High-Frequency Heart Rate Variability Reactivity and Trait Worry Interact to Predict the Development of Sleep Disturbances in Response to a Naturalistic Stressor.

PubMed

MacNeil, Sasha; Deschênes, Sonya S; Caldwell, Warren; Brouillard, Melanie; Dang-Vu, Thien-Thanh; Gouin, Jean-Philippe

2017-12-01

High-frequency heart rate variability (HF-HRV) reactivity was proposed as a vulnerability factor for stress-induced sleep disturbances. Its effect may be amplified among individuals with high trait worry or sleep reactivity. This study evaluated whether HF-HRV reactivity to a worry induction, sleep reactivity, and trait worry predict increases in sleep disturbances in response to academic stress, a naturalistic stressor. A longitudinal study following 102 undergraduate students during an academic semester with well-defined periods of lower and higher academic stress was conducted. HF-HRV reactivity to a worry induction, trait worry using the Penn State Worry Questionnaire, and sleep reactivity using the Ford Insomnia Stress Reactivity Test were measured during the low stress period. Sleep disturbances using the Pittsburgh Sleep Quality Index were assessed twice during the lower stress period and three times during the higher stress period. Greater reductions in HF-HRV in response to the worry induction predicted increases in sleep disturbances from the lower to the higher academic stress period. Trait worry moderated this association: individuals with both higher trait worry and greater HF-HRV reactivity to worry had larger increases in stress-related sleep disturbances over time, compared to participants with lower trait worry and HF-HRV reactivity. A similar, but marginally significant effect was found for sleep reactivity. This study supports the role of HF-HRV reactivity as a vulnerability factor for stress-induced sleep disturbances. The combination of high trait worry and high HF-HRV reactivity to worry might identify a subgroup of individuals most vulnerable to stress-related sleep disturbances.

The Circadian System Contributes to Apnea Lengthening across the Night in Obstructive Sleep Apnea

PubMed Central

Butler, Matthew P.; Smales, Carolina; Wu, Huijuan; Hussain, Mohammad V.; Mohamed, Yusef A.; Morimoto, Miki; Shea, Steven A.

2015-01-01

Study Objective: To test the hypothesis that respiratory event duration exhibits an endogenous circadian rhythm. Design: Within-subject and between-subjects. Settings: Inpatient intensive physiologic monitoring unit at the Brigham and Women's Hospital. Participants: Seven subjects with moderate/severe sleep apnea and four controls, age 48 (SD = 12) years, 7 males. Interventions: Subjects completed a 5-day inpatient protocol in dim light. Polysomnography was recorded during an initial control 8-h night scheduled at the usual sleep time, then through 10 recurrent cycles of 2 h 40 min sleep and 2 h 40 min wake evenly distributed across all circadian phases, and finally during another 8-h control sleep period. Measurements and Results: Event durations, desaturations, and apnea-hypopnea index for each sleep opportunity were assessed according to circadian phase (derived from salivary melatonin), time into sleep, and sleep stage. Average respiratory event durations in NREM sleep significantly lengthened across both control nights (21.9 to 28.2 sec and 23.7 to 30.2 sec, respectively). During the circadian protocol, event duration in NREM increased across the circadian phases that corresponded to the usual sleep period, accounting for > 50% of the increase across normal 8-h control nights. AHI and desaturations were also rhythmic: AHI was highest in the biological day while desaturations were greatest in the biological night. Conclusions: The endogenous circadian system plays an important role in the prolongation of respiratory events across the night, and might provide a novel therapeutic target for modulating sleep apnea. Citation: Butler MP, Smales C, Wu H, Hussain MV, Mohamed YA, Morimoto M, Shea SA. The circadian system contributes to apnea lengthening across the night in obstructive sleep apnea. SLEEP 2015;38(11):1793–1801. PMID:26039970

Reading from an iPad or from a book in bed: the impact on human sleep. A randomized controlled crossover trial.

PubMed

Grønli, Janne; Byrkjedal, Ida Kristiansen; Bjorvatn, Bjørn; Nødtvedt, Øystein; Hamre, Børge; Pallesen, Ståle

2016-05-01

To objectively and subjectively compare whether reading a story for 30 min from an iPad or from a book in bed prior to sleep will differentially affect sleep. Sixteen students (12 females, mean age 25.1 ± 2.9 years) underwent ambulatory (sleeping in their own beds at home) polysomnographic (PSG) recordings in a counterbalanced crossover design consisting of three PSG nights (one adaptation night, two test nights) and two different reading materials: read from an iPad or from a book. Illumination was measured during reading and Karolinska Sleepiness Scale was completed prior to turning the light off. Sleep diaries were kept to assess subjective sleep parameters from day to day. Illumination was higher in the iPad condition compared to the book condition (58.3 ± 6.9 vs 26.7 ± 8.0 lux, p <0.001). Reading a story from an iPad decreased subjective sleepiness, delayed the EEG dynamics of slow wave activity by approximately 30 min, and reduced slow wave activity after sleep onset compared to reading from a book. No parameters of sleep state timing and sleep onset latency differed between the two reading conditions. Although there was no direct effect on time spent in different sleep states and self-reported sleep onset latency, the use of an iPad which emits blue enriched light impinges acutely on sleepiness and EEG characteristics of sleep pressure. Hence, the use of commercially available tablets may have consequences in terms of alertness, circadian physiology, and sleep. Published by Elsevier B.V.

Sleep quality and duration are associated with performance in maximal incremental test.

PubMed

Antunes, B M; Campos, E Z; Parmezzani, S S; Santos, R V; Franchini, E; Lira, F S

2017-08-01

Inadequate sleep patterns may be considered a trigger to development of several metabolic diseases. Additionally, sleep deprivation and poor sleep quality can negatively impact performance in exercise training. However, the impact of sleep duration and sleep quality on performance during incremental maximal test performed by healthy men is unclear. Therefore, the purpose of the study was to analyze the association between sleep pattern (duration and quality) and performance during maximal incremental test in healthy male individuals. A total of 28 healthy males volunteered to take part in the study. Sleep quality, sleep duration and physical activity were subjectively assessed by questionnaires. Sleep pattern was classified by sleep duration (>7h or <7h of sleep per night) and sleep quality according to the sum of measured points and/or scores by the Pittsburgh Sleep Quality Index (PSQI). Incremental exercise test was performed at 35 watts for untrained subjects, 70 watts for physically active subjects and 105 watts for well-trained subjects. HR max was correlated with sleep quality (r=0.411, p=0.030) and sleep duration (r=-0.430, p=0.022). Participants reporting good sleep quality presented higher values of W max , VO 2max and lower values of HR max when compared to participants with altered sleep. Regarding sleep duration, only W max was influenced by the amount of sleeping hours per night and this association remained significant even after adjustment by VO 2max . Sleep duration and quality are associated, at least in part, with performance during maximal incremental test among healthy men, with losses in W max and HR max . In addition, our results suggest that the relationship between sleep patterns and performance, mainly in W max , is independent of fitness condition. Copyright © 2017 Elsevier Inc. All rights reserved.

Reliability of a single objective measure in assessing sleepiness.

PubMed

Sunwoo, Bernie Y; Jackson, Nicholas; Maislin, Greg; Gurubhagavatula, Indira; George, Charles F; Pack, Allan I

2012-01-01

To evaluate reliability of single objective tests in assessing sleepiness. Subjects who completed polysomnography underwent a 4-nap multiple sleep latency test (MSLT) the following day. Prior to each nap opportunity on MSLT, subjects performed the psychomotor vigilance test (PVT) and divided attention driving task (DADT). Results of single versus multiple test administrations were compared using the intraclass correlation coefficient (ICC) and adjusted for test administration order effects to explore time of day effects. Measures were explored as continuous and binary (i.e., impaired or not impaired). Community-based sample evaluated at a tertiary, university-based sleep center. 372 adult commercial vehicle operators oversampled for increased obstructive sleep apnea risk. N/A. AS CONTINUOUS MEASURES, ICC WERE AS FOLLOWS: MSLT 0.45, PVT median response time 0.69, PVT number of lapses 0.51, 10-min DADT tracking error 0.87, 20-min DADT tracking error 0.90. Based on binary outcomes, ICC were: MSLT 0.63, PVT number of lapses 0.85, 10-min DADT 0.95, 20-min DADT 0.96. Statistically significant time of day effects were seen in both the MSLT and PVT but not the DADT. Correlation between ESS and different objective tests was strongest for MSLT, range [-0.270 to -0.195] and persisted across all time points. Single DADT and PVT administrations are reliable measures of sleepiness. A single MSLT administration can reasonably discriminate individuals with MSL < 8 minutes. These results support the use of a single administration of some objective tests of sleepiness when performed under controlled conditions in routine clinical care.

An Endogenous Circadian Rhythm in Sleep Inertia Results in Greatest Cognitive Impairment upon Awakening during the Biological Night

PubMed Central

Scheer, Frank A. J. L.; Shea, Thomas J.; Hilton, Michael F.; Shea, Steven A.

2011-01-01

Sleep inertia is the impaired cognitive performance immediately upon awakening, which decays over tens of minutes. This phenomenon has relevance to people who need to make important decisions soon after awakening, such as on-call emergency workers. Such awakenings can occur at varied times of day or night, so the objective of the study was to determine whether or not the magnitude of sleep inertia varies according to the phase of the endogenous circadian cycle. Twelve adults (mean, 24 years; 7 men) with no medical disorders other than mild asthma were studied. Following 2 baseline days and nights, subjects underwent a forced desynchrony protocol composed of seven 28-h sleep/wake cycles, while maintaining a sleep/wakefulness ratio of 1:2 throughout. Subjects were awakened by a standardized auditory stimulus 3 times each sleep period for sleep inertia assessments. The magnitude of sleep inertia was quantified as the change in cognitive performance (number of correct additions in a 2-min serial addition test) across the first 20 min of wakefulness. Circadian phase was estimated from core body temperature (fitted temperature minimum assigned 0°). Data were segregated according to: (1) circadian phase (60° bins); (2) sleep stage; and (3) 3rd of the night after which awakenings occurred (i.e., tertiary 1, 2, or 3). To control for any effect of sleep stage, the circadian rhythm of sleep inertia was initially assessed following awakenings from Stage 2 (62% of awakening occurred from this stage; n = 110). This revealed a significant circadian rhythm in the sleep inertia of cognitive performance (p = 0.007), which was 3.6 times larger during the biological night (circadian bin 300°, ~2300–0300 h in these subjects) than during the biological day (bin 180°, ~1500–1900 h). The circadian rhythm in sleep inertia was still present when awakenings from all sleep stages were included (p = 0.004), and this rhythm could not be explained by changes in underlying sleep drive prior to awakening (changes in sleep efficiency across circadian phase or across the tertiaries), or by the proportion of the varied sleep stages prior to awakenings. This robust endogenous circadian rhythm in sleep inertia may have important implications for people who need to be alert soon after awakening. PMID:18663242

An endogenous circadian rhythm in sleep inertia results in greatest cognitive impairment upon awakening during the biological night.

PubMed

Scheer, Frank A J L; Shea, Thomas J; Hilton, Michael F; Shea, Steven A

2008-08-01

Sleep inertia is the impaired cognitive performance immediately upon awakening, which decays over tens of minutes. This phenomenon has relevance to people who need to make important decisions soon after awakening, such as on-call emergency workers. Such awakenings can occur at varied times of day or night, so the objective of the study was to determine whether or not the magnitude of sleep inertia varies according to the phase of the endogenous circadian cycle. Twelve adults (mean, 24 years; 7 men) with no medical disorders other than mild asthma were studied. Following 2 baseline days and nights, subjects underwent a forced desynchrony protocol composed of seven 28-h sleep/wake cycles, while maintaining a sleep/wakefulness ratio of 1:2 throughout. Subjects were awakened by a standardized auditory stimulus 3 times each sleep period for sleep inertia assessments. The magnitude of sleep inertia was quantified as the change in cognitive performance (number of correct additions in a 2-min serial addition test) across the first 20 min of wakefulness. Circadian phase was estimated from core body temperature (fitted temperature minimum assigned 0 degrees ). Data were segregated according to: (1) circadian phase (60 degrees bins); (2) sleep stage; and (3) 3rd of the night after which awakenings occurred (i.e., tertiary 1, 2, or 3). To control for any effect of sleep stage, the circadian rhythm of sleep inertia was initially assessed following awakenings from Stage 2 (62% of awakening occurred from this stage; n = 110). This revealed a significant circadian rhythm in the sleep inertia of cognitive performance (p = 0.007), which was 3.6 times larger during the biological night (circadian bin 300 degrees , approximately 2300-0300 h in these subjects) than during the biological day (bin 180 degrees , approximately 1500-1900 h). The circadian rhythm in sleep inertia was still present when awakenings from all sleep stages were included (p = 0.004), and this rhythm could not be explained by changes in underlying sleep drive prior to awakening (changes in sleep efficiency across circadian phase or across the tertiaries), or by the proportion of the varied sleep stages prior to awakenings. This robust endogenous circadian rhythm in sleep inertia may have important implications for people who need to be alert soon after awakening.

Poor habitual sleep efficiency is associated with increased cardiovascular and cortisol stress reactivity in men.

PubMed

Massar, Stijn A A; Liu, Jean C J; Mohammad, Nabilah B; Chee, Michael W L

2017-07-01

Inadequate sleep and psychological stress can both elevate physiological stress markers, such as cortisol. Prior studies that have applied induced psychosocial stress after a night of experimental sleep deprivation have found these effects to be compounded. We examined whether the relationship between stress reactivity and poor sleep also extends to habitual sleep patterns. Fifty-nine adult male participants were recruited. Habitual sleep patterns were monitored with actigraphy for a week. Participants subsequently underwent the Trier Social Stress Test. Cardiovascular responses and salivary cortisol were measured at baseline, during stress, and during recovery. Subjects who showed poor habitual sleep efficiency during the week before stress induction responded with higher stress-related elevations of blood pressure and cortisol levels as compared to subjects with high sleep efficiency. This relationship between poor sleep efficiency and elevated blood pressure persisted during the post-stress recovery period. Similar associations between total sleep time in the week prior to the stress induction and physiological reactivity did not reach significance. Our findings indicate that habitual low sleep efficiency exaggerates cardiovascular and neuroendocrine effects of psychosocial stress, in a male population. Copyright © 2017 Elsevier Ltd. All rights reserved.

Brief periods of NREM sleep do not promote early offline gains but subsequent on-task performance in motor skill learning.

PubMed

Maier, Jonathan G; Piosczyk, Hannah; Holz, Johannes; Landmann, Nina; Deschler, Christoph; Frase, Lukas; Kuhn, Marion; Klöppel, Stefan; Spiegelhalder, Kai; Sterr, Annette; Riemann, Dieter; Feige, Bernd; Voderholzer, Ulrich; Nissen, Christoph

2017-11-01

Sleep modulates motor learning, but its detailed impact on performance curves remains to be fully characterized. This study aimed to further determine the impact of brief daytime periods of NREM sleep on 'offline' (task discontinuation after initial training) and 'on-task' (performance within the test session) changes in motor skill performance (finger tapping task). In a mixed design (combined parallel group and repeated measures) sleep laboratory study (n=17 'active' wake vs. sleep, n=19 'passive' wake vs. sleep), performance curves were assessed prior to and after a 90min period containing either sleep, active or passive wakefulness. We observed a highly significant, but state- (that is, sleep/wake)-independent early offline gain and improved on-task performance after sleep in comparison to wakefulness. Exploratory curve fitting suggested that the observed sleep effect most likely emerged from an interaction of training-induced improvement and detrimental 'time-on-task' processes, such as fatigue. Our results indicate that brief periods of NREM sleep do not promote early offline gains but subsequent on-task performance in motor skill learning. Copyright © 2017 Elsevier Inc. All rights reserved.

Association between sleep quality and nurse productivity among Korean clinical nurses.

PubMed

Park, Eunok; Lee, Hyo Young; Park, Claire Su-Yeon

2018-06-01

To determine the association between sleep quality and nurse productivity. Although poor sleep quality may decrease nurses' productivity, the association between the two has not yet been evaluated in the literature. A cross-sectional survey was completed in May 2014 by 188 nurses working in acute hospitals in South Korea using the Pittsburgh Sleep Quality Index. Descriptive statistics, t tests, ANOVA, Pearson's correlation, and stepwise multiple regression were conducted for data analysis. The prevalence of poor sleep quality was high (79.8%). Among the components of sleep quality, sleep disturbances (β = -0.19) and subjective sleep quality (β = -0.16) were determined to be statistically significant predictive factors of nurse productivity, in addition to shift work (β = -0.20) and age (β = 0.32). Poor sleep quality may lead to lower nurse productivity. Nurse leaders and executives should consider measures to improve nurses' sleep quality and enhance nurse productivity. Steps that need to be considered include longer intervals between shift-work cycles, clockwise scheduling order, a longer break time after night shift work, allowing nurses to nap before / during a night shift, and providing a worksite healthy sleep programme. © 2018 John Wiley & Sons Ltd.

Word encoding during sleep is suggested by correlations between word-evoked up-states and post-sleep semantic priming

PubMed Central

Ruch, Simon; Koenig, Thomas; Mathis, Johannes; Roth, Corinne; Henke, Katharina

2014-01-01

To test whether humans can encode words during sleep we played everyday words to men while they were napping and assessed priming from sleep-played words following waking. Words were presented during non-rapid eye movement (NREM) sleep. Priming was assessed using a semantic and a perceptual priming test. These tests measured differences in the processing of words that had been or had not been played during sleep. Synonyms to sleep-played words were the targets in the semantic priming test that tapped the meaning of sleep-played words. All men responded to sleep-played words by producing up-states in their electroencephalogram. Up-states are NREM sleep-specific phases of briefly increased neuronal excitability. The word-evoked up-states might have promoted word processing during sleep. Yet, the mean performance in the priming tests administered following sleep was at chance level, which suggests that participants as a group failed to show priming following sleep. However, performance in the two priming tests was positively correlated to each other and to the magnitude of the word-evoked up-states. Hence, the larger a participant's word-evoked up-states, the larger his perceptual and semantic priming. Those participants who scored high on all variables must have encoded words during sleep. We conclude that some humans are able to encode words during sleep, but more research is needed to pin down the factors that modulate this ability. PMID:25452740

Internet-Delivered Cognitive-Behavioral Therapy for Insomnia in Breast Cancer Survivors: A Randomized Controlled Trial.

PubMed

Zachariae, Robert; Amidi, Ali; Damholdt, Malene F; Clausen, Cecilie D R; Dahlgaard, Jesper; Lord, Holly; Thorndike, Frances P; Ritterband, Lee M

2018-02-20

Insomnia is two to three times more prevalent in cancer survivors than in the general population, where it is estimated to be 10% to 20%. Cognitive-behavioral therapy for insomnia (CBT-I) is the recommended treatment for chronic insomnia, but meeting survivor needs remains a challenge. Internet-delivered CBT-I (iCBT-I) has been shown efficacious in otherwise healthy adults. We tested the efficacy of iCBT-I in breast cancer survivors with clinically significant sleep disturbance. Women from a national sample of Danish breast cancer survivors who experienced clinically significant sleep disturbance were randomly allocated to iCBT-I or waitlist control (55:45). The fully automated iCBT-I program consisted of six cores. Online measures of insomnia severity, sleep quality, and fatigue were collected at baseline, postintervention (nine weeks), and follow-up (15 weeks). Online sleep diaries were completed over two-week periods pre- and postintervention. Intention-to-treat analyses (time × group interactions) were conducted with mixed linear models and corrected for multiple outcomes. All statistical tests were two-sided. A total of 255 women were randomly allocated to iCBT-I (n = 133) or waitlist control (n = 122). Statistically significant (P ≤ .02) time × group interactions were found for all sleep-related outcomes from pre- to postintervention. Effect sizes (Cohen's d) ranged from 0.33 (95% confidence interval [CI] = 0.06 to 0.61) for wake after sleep onset to 1.17 (95% CI = 0.87 to 1.47) for insomnia severity. Improvements were maintained for outcomes measured at follow-up (d = 0.66-1.10). iCBT-I appears to be effective in breast cancer survivors, with additional benefit in terms of reduced fatigue. This low-cost treatment could be incorporated in cancer rehabilitation programs.

Workload, mental health and burnout indicators among female physicians.

PubMed

Győrffy, Zsuzsa; Dweik, Diana; Girasek, Edmond

2016-04-01

Female doctors in Hungary have worse indicators of physical and mental health compared with other professional women. We aimed to cast light on possible indicators of mental health, workload, and burnout of female physicians. Two time-points (T) were compared, in 2003 (T1 n = 408) and 2013 (T2 n = 2414), based on two nationally representative surveys of female doctors, and comparison made with data from other professional control groups. Independent samples t test or chi-squared test was used both for the two time-point comparison and the comparison between the index and the control groups. The background factors of sleep disorders and burnout were assessed by binary logistic regression analysis. No significant differences in the rates of depressive symptoms and suicidal thoughts and attempts were detected between the 2003 and 2013 cohorts, but the prevalence of sleep disorders increased. The workload increased, and there was less job satisfaction in 2013 than in 2003, coupled to more stressful or difficult work-related situations. The personal accomplishment component of burnout significantly decreased in line with the declining work-related satisfaction. Compared to the professional control groups, the prevalence of depressive symptoms, suicide attempts, and sleep disorders was higher among female physicians at both time-points. The number of workplaces, frequency of work-related stressful situations, and intensive role conflict was associated with sleep disorders and decreased personal accomplishment. In comparison with the other professional groups, female doctors had worse mental health indicators with regard to depression, suicidal ideas, and sleep disorders both in 2003 and 2013 while within professional strata the changes seemed to be less. Increasing workload had a clear impact on sleep disorders and the personal accomplishment dimension of burnout.

Desmopressin (melt) therapy in children with monosymptomatic nocturnal enuresis and nocturnal polyuria results in improved neuropsychological functioning and sleep.

PubMed

Van Herzeele, Charlotte; Dhondt, Karlien; Roels, Sanne P; Raes, Ann; Hoebeke, Piet; Groen, Luitzen-Albert; Vande Walle, Johan

2016-09-01

There is a high comorbidity between nocturnal enuresis, sleep disorders and psychological problems. The aim of this study was to investigate whether a decrease in nocturnal diuresis volume not only improves enuresis but also ameliorates disrupted sleep and (neuro)psychological dysfunction, the major comorbidities of this disorder. In this open-label, prospective phase IV study, 30 children with monosymptomatic nocturnal enuresis (MNE) underwent standardized video-polysomnographic testing and multi-informant (neuro)psychological testing at baseline and 6 months after the start of desmopressin treatment in the University Hospital Ghent, Belgium. Primary endpoints were the effect on sleep and (neuro)psychological functioning. The secondary endpoint was the change in the first undisturbed sleep period or the time to the first void. Thirty children aged between 6 and 16 (mean 10.43, standard deviation 3.08) years completed the study. The results demonstrated a significant decrease in periodic limb movements during sleep (PLMS) and a prolonged first undisturbed sleep period. Additionally, (neuro)psychological functioning was improved on several domains. The study demonstrates that the degree of comorbidity symptoms is at least aggravated by enuresis (and/or high nocturnal diuresis rate) since sleep and (neuro)psychological functioning were significantly ameliorated by treatment of enuresis. These results indicate that enuresis is not such a benign condition as has previously been assumed.

Sleep loss impairs short and novel language tasks having a prefrontal focus.

PubMed

Harrison, Y; Horne, J A

1998-06-01

Most cognitive tests administered during sleep loss are well rehearsed to remove practice effects. This can introduce tedium and a loss of novelty, which may be the key to the test's subsequent sensitivity to sleep loss, and why it may need only a few minutes administration before sleep loss effects are apparent. There is little evidence to show that any of these tests are actually affected by sleep loss is given de novo, without practice, but using a non-sleep deprived control group. Although the sleep deprivation literature advocates that short, novel and stimulating tests would not be expected to be sensitive to sleep loss, recent sleep loss findings using neuropsychological tests focussing on the prefrontal cortex, indicate that such tests may challenge this maxim. Twenty healthy young adults were randomly assigned to two groups: nil sleep deprivation (control). and 36h continuous sleep deprivation (SD). Two, novel, interesting and short (6 min) language tests, known (by brain imaging) to have predominantly a PFC focus, were given, once, towards the end of SD: (i) the Haylings test--which measures the capacity to inhibit strong associations in favour of novel responses, and (ii) a variant of the word fluency test--innovation in a verb-to-noun association. Subjects were exhorted to do their best. Compared with control subjects both tasks were significantly impaired by SD. As a check on the effects on the Haylings test, a repeat study was undertaken with 30 more subjects randomly divided as before. The outcome was similar. Linguistically, sleep loss appears to interfere with novel responses and the ability to suppress routine answers.

Sleepiness and Sleep Disordered Breathing in Prader-Willi Syndrome: Relationship to Genotype, Growth Hormone Therapy, and Body Composition

PubMed Central

Williams, Korwyn; Scheimann, Ann; Sutton, Vernon; Hayslett, Elizabeth; Glaze, Daniel G.

2008-01-01

Study Objectives: Patients with Prader-Willi syndrome (PWS) suffer from excessive sleepiness and sleep disordered breathing (SDB). We reviewed the polysomnograms (PSGs) and multiple sleep latency tests (MSLTs) in a cohort of PWS patients to determine the relationship of BMIz scores, daytime sleepiness, growth hormone (GH) treatments, and SDB. Methods: Attended overnight PSGs were performed for PWS patients referred for concern for SDB between January 2000 and January 2005. Age at time of study, genotype, use and dose of GH, sleepiness scale, normalized body-mass index (BMIz), total sleep time, latency to stage I and REM sleep, sleep stage percentages, apnea-hypopnea index (AHI), central apnea (CA) frequency, oxygen saturation nadir, maximum carbon dioxide tension, periodic limb movement index, presence of snoring, normality of EEG, and, in several patients, mean sleep latency testing were determined. Results: All patients exhibited some form of SDB. There was a positive correlation between the BMIz and AHI. The BMIz was significantly different between GH–treated and –untreated groups, but there was not a significant difference between AHI, CA, oxygen nadir, or maximum carbon dioxide tension of the GH–treated and –untreated groups. There was no significant correlation between the MSLT and the sleepiness scale or AHI. There was also no significant difference between the AHIs of patients with different genetic defects. Conclusions: There should be a low threshold for obtaining PSG to evaluate SDB, but the type and severity of SDB were not predictable based on a sleepiness scale score, BMIz, or underlying genetic defect. Citation: Williams K; Scheimann A; Sutton V; Hayslett E; Glaze DG. Sleepiness and sleep disordered breathing in Prader-Willi syndrome: relationship to genotype, growth hormone therapy, and body composition. J Clin Sleep Med 2007;4(2):111–118. PMID:18468308

Critical evaluation of the effect of valerian extract on sleep structure and sleep quality.

PubMed

Donath, F; Quispe, S; Diefenbach, K; Maurer, A; Fietze, I; Roots, I

2000-03-01

A carefully designed study assessed the short-term (single dose) and long-term (14 days with multiple dosage) effects of a valerian extract on both objective and subjective sleep parameters. The investigation was performed as a randomised, double-blind, placebo-controlled, cross-over study. Sixteen patients (4 male, 12 female) with previously established psychophysiological insomnia (ICSD-code 1.A.1.), and with a median age of 49 (range: 22 to 55), were included in the study. The main inclusion criteria were reported primary insomnia according to ICSD criteria, which was confirmed by polysomnographic recording, and the absence of acute diseases. During the study, the patients underwent 8 polysomnographic recordings: i.e., 2 recordings (baseline and study night) at each time point at which the short and long-term effects of placebo and valerian were tested. The target variable of the study was sleep efficiency. Other parameters describing objective sleep structure were the usual features of sleep-stage analysis, based on the rules of Rechtschaffen and Kales (1968), and the arousal index (scored according to ASDA criteria, 1992) as a sleep microstructure parameter. Subjective parameters such as sleep quality, morning feeling, daytime performance, subjectively perceived duration of sleep latency, and sleep period time were assessed by means of questionnaires. After a single dose of valerian, no effects on sleep structure and subjective sleep assessment were observed. After multiple-dose treatment, sleep efficiency showed a significant increase for both the placebo and the valerian condition in comparison with baseline polysomnography. We confirmed significant differences between valerian and placebo for parameters describing slow-wave sleep. In comparison with the placebo, slow-wave sleep latency was reduced after administration of valerian (21.3 vs. 13.5 min respectively, p<0.05). The SWS percentage of time in bed (TIB) was increased after long-term valerian treatment, in comparison to baseline (9.8 vs. 8.1% respectively, p<0.05). At the same time point, a tendency for shorter subjective sleep latency, as well as a higher correlation coefficient between subjective and objective sleep latencies, were observed under valerian treatment. Other improvements in sleep structure - such as an increase in REM percentage and a decrease in NREM1 percentage - took place simultaneously under placebo and valerian treatment. A remarkable finding of the study was the extremely low number of adverse events during the valerian treatment periods (3 vs. 18 in the placebo period). In conclusion, treatment with a herbal extract of radix valerianae demonstrated positive effects on sleep structure and sleep perception of insomnia patients, and can therefore be recommended for the treatment of patients with mild psychophysiological insomnia.

Effects of Zolpidem CR on Sleep and Nocturnal Ventilation in Patients with Heart Failure

PubMed Central

Gatti, Rodrigo C.; Burke, Patrick R.; Otuyama, Leonardo J.; Almeida, Dirceu R.; Tufik, Sergio; Poyares, Dalva

2016-01-01

Study Objective: This study aimed to evaluate the effects of zolpidem CR (controlled release) on sleep and nocturnal ventilation in patients with congestive heart failure, a population at risk for insomnia and poor sleep quality. Methods: Fifteen patients with heart failure (ischemic cardiomyopathy) and ejection fraction ≤ 45% in NYHA functional class I or II were evaluated with full polysomnography in a placebo-controlled, double-blind, randomized trial. Patients underwent three tests: (1) baseline polysomnography and, after randomization, (2) a new test with zolpidem CR 12.5 mg or placebo, and after 1 week, (3) a new polysomnography, crossing the “medication” used. Results: A 16% increase in total sleep time was found with the use of zolpidem CR and an increase in stage 3 NREM sleep (slow wave sleep). The apnea hypopnea index (AHI) did not change with zolpidem CR even after controlling for supine position; however, a slight but significant decrease was observed in lowest oxygen saturation compared with baseline and placebo conditions (83.60 ± 5.51; 84.43 ± 3.80; 80.71 ± 5.18, P = 0.002). Conclusion: Zolpidem CR improved sleep structure in patients with heart failure, did not change apnea hypopnea index, but slightly decreased lowest oxygen saturation. Citation: Gatti RC, Burke PR, Otuyama LJ, Almeida DR, Tufik S, Poyares D. Effects of zolpidem CR on sleep and nocturnal ventilation in patients with heart failure. SLEEP 2016;39(8):1501–1505. PMID:27166233

Sleep indices and eating behaviours in young adults: findings from Project EAT.

PubMed

Ogilvie, Rachel P; Lutsey, Pamela L; Widome, Rachel; Laska, Melissa N; Larson, Nicole; Neumark-Sztainer, Dianne

2018-03-01

To test the associations between sleep indices and eating behaviours in young adults, a group vulnerable to suboptimal sleep. Cross-sectional analysis of survey measures of sleep (i.e. time in bed, variability, timing and quality) and dietary patterns (i.e. breakfast skipping, eating at fast-food restaurants, consumption of sports and energy drinks, and sugar-free, sugar-sweetened and caffeinated beverages). Minneapolis/St. Paul metropolitan area of Minnesota (USA). A total of 1854 respondents (20-30 years, 55·6 % female) from the 2008-2009 survey conducted for the third wave of the population-based Project EAT (Eating and Activity in Teens and Young Adults) study. After adjustment for demographic and behavioural covariates in linear regression models, those who went to bed after 00.30 hours consumed 0·3 more servings of sugar-sweetened beverages per day, consumed 1·7 times more energy drinks, skipped breakfast 1·8 more times per week and consumed fast food 0·3 more times per week compared with those who went to bed before 22.30 hours. Reported sleep quality in the lowest (Q1) v. highest (Q3) tertile was associated with more intake of energy drinks (Q3 v. Q1, prevalence ratio, 95 % CI: 1·79, 1·24, 2·34), sports drinks (1·28, 1·00, 1·55) and breakfast skipping (adjusted mean, 95 % CI: Q1: 4·03, 3·81, 4·26; Q3: 3·43, 3·17, 3·69). Time in bed and sleep variability were associated with few eating behaviours. Some, but not all, sleep indices were related to problematic eating behaviours. Sleep habits may be important to address in interventions and policies that target improvements in eating patterns and health outcomes.

Technology Use and Sleep Quality in Preadolescence and Adolescence

PubMed Central

Bruni, Oliviero; Sette, Stefania; Fontanesi, Lilybeth; Baiocco, Roberto; Laghi, Fiorenzo; Baumgartner, Emma

2015-01-01

Study Objectives: The purpose of this study was to analyze differences between preadolescents and adolescents on the use of technology and to test the contribution of using Internet and mobile phone, and circadian preference on sleep quality. Methods: We recruited a sample of 850 (364 males) preadolescents and adolescents. Self-report questionnaires about sleep schedule, sleep wake behavior problems, circadian preferences, and the use of technology (e.g., Internet and mobile phone) were administered. Students were asked to fill out the School Sleep Habits Survey, a self-report questionnaire on the use of technology, the Mobile Phone Involvement Questionnaire (MPIQ), and the Shorter Promis Questionnaire (SPQ). Results: Adolescents reported more sleep problems, a tendency toward eveningness, and an increase of Internet and phone activities, as well as social network activities, while preadolescents were more involved in gaming console and television viewing. The regression analysis performed separately in the two age groups showed that sleep quality was affected by the circadian preference (eveningness) in both groups. Adolescents' bad sleep quality was consistently associated with the mobile phone use and number of devices in the bedroom, while in preadolescents, with Internet use and turning-off time. Conclusions: The evening circadian preference, mobile phone and Internet use, numbers of other activities after 21:00, late turning off time, and number of devices in the bedroom have different negative influence on sleep quality in preadolescents and adolescents. Citation: Bruni O, Sette S, Fontanesi L, Baiocco R, Laghi F, Baumgartner E. Technology use and sleep quality in preadolescence and adolescence. J Clin Sleep Med 2015;11(12):1433–1441. PMID:26235161

The effects of caffeine ingestion on the reaction time and short-term maximal performance after 36 h of sleep deprivation.

PubMed

Souissi, Makram; Chtourou, Hamdi; Abedelmalek, Salma; Ghozlane, Imen Ben; Sahnoun, Zouhair

2014-05-28

The aim of the present study was to investigate the effects of caffeine ingestion on cognitive and physical performances after 36h of sleep deprivation. In randomized order, thirteen healthy male physical education students (age: 21.1±1.1years, body mass: 77.1±7.2kg, height: 1.77±0.06m) completed four test sessions at 18:00h: after placebo or 5mg·kg(-1) of caffeine ingestion during a baseline night (RN) (bed time: from 22:30h to 07:00h) or a night of 36h of sleep deprivation (TSD). During each test session, participants performed the squat jump (SJ), the reaction time, and the 30-s Wingate tests (i.e., for the measurement of the peak (PP) and mean (MP) powers and the fatigue index (FI)). The results showed that PP and MP decreased and FI increased during the TSD compared to RN in the placebo condition (p<0.001). The caffeine ingestion improved PP after TSD compared to RN (p<0.001). SJ decreased significantly after the TSD compared to RN after both placebo and caffeine ingestions (p<0.001). However, SJ increased significantly after caffeine ingestion during RN and TSD (p<0.001). The reaction time increased significantly after TSD compared to RN (p<0.001). However, the reaction time decreased significantly after the caffeine ingestion only during the TSD (p<0.001). Therefore, caffeine is an effective strategy to counteract the effect of 36h of sleep loss on physical and cognitive performances. Copyright © 2014 Elsevier Inc. All rights reserved.

Recovery of Neurological Function Despite Immediate Sleep Disruption Following Diffuse Brain Injury in the Mouse: Clinical Relevance to Medically Untreated Concussion

PubMed Central

Rowe, Rachel K.; Harrison, Jordan L.; O'Hara, Bruce F.; Lifshitz, Jonathan

2014-01-01

Study Objective: We investigated the relationship between immediate disruption of posttraumatic sleep and functional outcome in the diffuse brain-injured mouse. Design: Adult male C57BL/6 mice were subjected to moderate midline fluid percussion injury (n = 65; 1.4 atm; 6-10 min righting reflex time) or sham injury (n = 44). Cohorts received either intentional sleep disruption (minimally stressful gentle handling) or no sleep disruption for 6 h following injury. Following disruption, serum corticosterone levels (enzyme-linked immunosorbent assay) and posttraumatic sleep (noninvasive piezoelectric sleep cages) were measured. For 1-7 days postinjury, sensorimotor outcome was assessed by Rotarod and a modified Neurological Severity Score (NSS). Cognitive function was measured using Novel Object Recognition (NOR) and Morris water maze (MWM) in the first week postinjury. Setting: Neurotrauma research laboratory. Measurements and Results: Disrupting posttraumatic sleep for 6 h did not affect serum corticosterone levels or functional outcome. In the hour following the first dark onset, sleep-disrupted mice exhibited a significant increase in sleep; however, this increase was not sustained and there was no rebound of lost sleep. Regardless of sleep disruption, mice showed a time-dependent improvement in Rotarod performance, with brain-injured mice having significantly shorter latencies on day 7 compared to sham. Further, brain-injured mice, regardless of sleep disruption, had significantly higher NSS scores postinjury compared with sham. Cognitive behavioral testing showed no group differences among any treatment group measured by MWM and NOR. Conclusion: Short-duration disruption of posttraumatic sleep did not affect functional outcome, measured by motor and cognitive performance. These data raise uncertainty about posttraumatic sleep as a mechanism of recovery from diffuse brain injury. Citation: Rowe RK; Harrison JL; O'Hara BF; Lifshitz J. Recovery of neurological function despite immediate sleep disruption following diffuse brain injury in the mouse: clinical relevance to medically untreated concussion. SLEEP 2014;37(4):743-752. PMID:24899763

Evidence for cortical structural plasticity in humans after a day of waking and sleep deprivation.

PubMed

Elvsåshagen, Torbjørn; Zak, Nathalia; Norbom, Linn B; Pedersen, Per Ø; Quraishi, Sophia H; Bjørnerud, Atle; Alnæs, Dag; Doan, Nhat Trung; Malt, Ulrik F; Groote, Inge R; Westlye, Lars T

2017-08-01

Sleep is an evolutionarily conserved process required for human health and functioning. Insufficient sleep causes impairments across cognitive domains, and sleep deprivation can have rapid antidepressive effects in mood disorders. However, the neurobiological effects of waking and sleep are not well understood. Recently, animal studies indicated that waking and sleep are associated with substantial cortical structural plasticity. Here, we hypothesized that structural plasticity can be observed after a day of waking and sleep deprivation in the human cerebral cortex. To test this hypothesis, 61 healthy adult males underwent structural magnetic resonance imaging (MRI) at three time points: in the morning after a regular night's sleep, the evening of the same day, and the next morning, either after total sleep deprivation (N=41) or a night of sleep (N=20). We found significantly increased right prefrontal cortical thickness from morning to evening across all participants. In addition, pairwise comparisons in the deprived group between the two morning scans showed significant thinning of mainly bilateral medial parietal cortices after 23h of sleep deprivation, including the precuneus and posterior cingulate cortex. However, there were no significant group (sleep vs. sleep deprived group) by time interactions and we can therefore not rule out that other mechanisms than sleep deprivation per se underlie the bilateral medial parietal cortical thinning observed in the deprived group. Nonetheless, these cortices are thought to subserve wakefulness, are among the brain regions with highest metabolic rate during wake, and are considered some of the most sensitive cortical regions to a variety of insults. Furthermore, greater thinning within the left medial parietal cluster was associated with increased sleepiness after sleep deprivation. Together, these findings add to a growing body of data showing rapid structural plasticity within the human cerebral cortex detectable with MRI. Further studies are needed to clarify whether cortical thinning is one neural substrate of sleepiness after sleep deprivation. Copyright © 2017 Elsevier Inc. All rights reserved.

Effects of different sleep deprivation protocols on sleep perception in healthy volunteers.

PubMed

Goulart, Leonardo I; Pinto, Luciano R; Perlis, Michael L; Martins, Raquel; Caboclo, Luis Otavio; Tufik, Sergio; Andersen, Monica L

2014-10-01

To investigate whether different protocols of sleep deprivation modify sleep perception. The effects of total sleep deprivation (TD) and selective rapid eye movement (REM) sleep deprivation (RD) on sleep perception were analyzed in normal volunteers. Thirty-one healthy males with normal sleep were randomized to one of three conditions: (i) normal uninterrupted sleep; (ii) four nights of RD; or (iii) two nights of TD. Morning perception of total sleep time was evaluated for each condition. Sleep perception was estimated using total sleep time (in hours) as perceived by the volunteer divided by the total sleep time (in hours) measured by polysomnography (PSG). The final value of this calculation was defined as the perception index (PI). There were no significant differences among the three groups of volunteers in the total sleep time measured by PSG or in the perception of total sleep time at baseline condition. Volunteers submitted to RD exhibited lower sleep PI scores as compared with controls during the sleep deprivation period (P <0.05). Both RD and TD groups showed PI similar to controls during the recovery period. Selective REM sleep deprivation reduced the ability of healthy young volunteers to perceive their total sleep time when compared with time measured by PSG. The data reinforce the influence of sleep deprivation on sleep perception. Copyright © 2014 Elsevier B.V. All rights reserved.

Evaluation of n-hexane extract of Viola betonicifolia for its neuropharmacological properties.

PubMed

Muhammad, Naveed; Saeed, Muhammad; Khan, Haroon; Haq, Ikramul

2013-01-01

Viola betonicifolia (whole plant) has been used as a sedative and in various nervous disorders in Pakistani traditional medicines. The n-hexane extract of the whole plant of V. betonicifolia (HEVB) was investigated for neuropharmacological properties such as anxiolytic, muscle relaxant, sleep induction, antidepressant and sedative to ascertain its folk use. Anxiolytic activity was tested using the staircase test, while the muscle relaxing property of the extract was tested in various muscle relaxant paradigms, i.e. chimney test, traction test, rota rod and inclined plane. In anxiolytic and muscle relaxant tests, HEVB (0.3, 0.4 and 0.5 g/kg, i.p.), diazepam (1 mg/kg, i.p.) or distilled water (10 ml/kg i.p.) were administered 30, 60 and 90 min before performing the tests in mice. HEVB was also screened for a sleep-inducing effect. The antidepressant activity was determined by using the forced swimming test (FST), while line crossing in a special box was used for locomotor activity. HEVB showed a significant (P < 0.05) dose-dependent anxiolytic action in the staircase test. In muscle relaxant paradigms, a dose-dependent muscle relaxation was observed. For the phenobarbitone sleep induction test, HEVB notably (P < 0.05) reduced the latency time and increased the total sleeping duration. However, HEVB was devoid of any antidepressant activity, while the movements of mice were reduced significantly (P < 0.05) in locomotor activity. The results suggest that HEVB has anxiolytic, muscle relaxant, sleep-inducing (sedative) activity and, thus, provides pharmacological justification for the use of this plant as a sedative and for the relief of various nervous disorders.

Analyses of the Complexity of Patients Undergoing Attended Polysomnography in the Era of Home Sleep Apnea Tests

PubMed Central

Colaco, Brendon; Herold, Daniel; Johnson, Matthew; Roellinger, Daniel; Naessens, James M.; Morgenthaler, Timothy I.

2018-01-01

Study Objectives: Health care complexity includes dimensions of patient comorbidity and the level of services needed to meet patient demands. Home sleep apnea tests (HSAT) are increasingly used to test medically uncomplicated patients suspected of having moderate to severe obstructive sleep apnea (OSA). Patients with significant comorbidities or other sleep disorders are not candidates for HSAT and require attended in-center polysomnography. We hypothesized that this trend would result in increasingly complex patients being studied in sleep centers. Methods: Our study had two parts. To ascertain trends in sleep patient comorbidity, we used administrative diagnostic codes from patients undergoing polysomnography at the Mayo Clinic Center for Sleep Medicine from 2005 to June 2015 to calculate the Charlson and the Elixhauser comorbidity indices. We measured the level of services provided in two ways: (1) in a subset of patients from the past 2 months of 2015, we evaluated correlation of these morbidity indices with an internally developed Polysomnogram Clinical Index (PSGCI) rating anticipated patient care needs from 0 to 3 and (2) we measured the sleep study complexity based on polysomnography protocol design. Results: In 43,780 patients studied from 2005 to June 2015, the Charlson index increased from a mean of 1.38 to 1.88 (3.1% per year, P < .001) and the mean Elixhauser index increased from 2.61 to 3.35 (2.5% per year, P < .001). Both comorbidity indices were significantly higher at the highest (Level 3) level of the PSGCI (P < .001), and sleep study complexity increased over time. Conclusions: The complexity of patients undergoing attended polysomnography has increased by 28% to 36% over the past decade as measured by validated comorbidity indices, and these indices correlate with the complexity of rendered care during polysomnography. These findings have implications for increasing requirements for staffing, monitoring capabilities, and facility design of future sleep centers. Commentary: A commentary on this article appears in this issue on page 499. Citation: Colaco B, Herold D, Johnson M, Roellinger D, Naessens JM, Morgenthaler TI. Analyses of the complexity of patients undergoing attended polysomnography in the era of home sleep apnea tests. J Clin Sleep Med. 2018;14(4):631–639. PMID:29609716

A Collaborative Paradigm for Improving Management of Sleep Disorders in Primary Care: A Randomized Clinical Trial.

PubMed

Edinger, Jack D; Grubber, Janet; Ulmer, Christi; Zervakis, Jennifer; Olsen, Maren

2016-01-01

To test a collaborative care model for interfacing sleep specialists with primary care providers to enhance patients' sleep disorders management. This study used a randomized, parallel group, clinical intervention trial design. A total of 137 adult (29 women) VA outpatients with sleep complaints were enrolled and randomly assigned to (1) an intervention (INT) consisting of a one-time consultation with a sleep specialist who provided diagnostic feedback and treatment recommendations to the patient and the patient's primary care provider; or (2) a control condition consisting of their usual primary care (UPC). Provider-focused outcomes included rates of adherence to recommended diagnostic procedures and sleep-focused interventions. Patient-focused outcomes included measures taken from sleep diaries and actigraphy; Pittsburgh Sleep Quality Index (PSQI) scores; and self-report measures of sleepiness, fatigue, mood, quality of life, and satisfaction with health care. The proportions of provider-initiated sleep-focused interventions were significantly higher in the INT group than in the UPC group for polysomnography referrals (49% versus 6%; P < 0.001) and mental health clinic referrals (19% versus 6%; P = 0.02). At the 10-mo follow up, INT recipients showed greater estimated mean reductions in diary total wake time (-17.0 min; 95% confidence interval [CI]: -30.9, -3.1; P = 0.02) and greater increases in sleep efficiency (+3.7%; 95% CI: 0.8, 6.5; P = 0.01) than did UPC participants. A greater proportion of the INT group showed ≥ 1 standard deviation decline on the PSQI from baseline to the 10-mo follow-up (41% versus 21%; P = 0.02). Moreover, 69% of the INT group had normal (≤ 10) Epworth Sleepiness Scale scores at the 10-mo follow-up, whereas only 50% of the UPC group fell below this clinical cutoff (P = 0.03). A one-time sleep consultation significantly increased healthcare providers' attention to sleep problems and resulted in benefits to patients' sleep/wake symptoms. This study is registered with clinicaltrials.gov with identifier # NCT00390572. © 2016 Associated Professional Sleep Societies, LLC.

Why Does Sleep Slow-Wave Activity Increase After Extended Wake? Assessing the Effects of Increased Cortical Firing During Wake and Sleep

PubMed Central

Rodriguez, Alexander V.; Funk, Chadd M.; Vyazovskiy, Vladyslav V.; Nir, Yuval; Tononi, Giulio

2016-01-01

During non-rapid eye movement (NREM) sleep, cortical neurons alternate between ON periods of firing and OFF periods of silence. This bi-stability, which is largely synchronous across neurons, is reflected in the EEG as slow waves. Slow-wave activity (SWA) increases with wake duration and declines homeostatically during sleep, but the underlying mechanisms remain unclear. One possibility is neuronal “fatigue”: high, sustained firing in wake would force neurons to recover with more frequent and longer OFF periods during sleep. Another possibility is net synaptic potentiation during wake: stronger coupling among neurons would lead to greater synchrony and therefore higher SWA. Here, we obtained a comparable increase in sustained firing (6 h) in cortex by: (1) keeping mice awake by exposure to novel objects to promote plasticity and (2) optogenetically activating a local population of cortical neurons at wake-like levels during sleep. Sleep after extended wake led to increased SWA, higher synchrony, and more time spent OFF, with a positive correlation between SWA, synchrony, and OFF periods. Moreover, time spent OFF was correlated with cortical firing during prior wake. After local optogenetic stimulation, SWA and cortical synchrony decreased locally, time spent OFF did not change, and local SWA was not correlated with either measure. Moreover, laser-induced cortical firing was not correlated with time spent OFF afterward. Overall, these results suggest that high sustained firing per se may not be the primary determinant of SWA increases observed after extended wake. SIGNIFICANCE STATEMENT A long-standing hypothesis is that neurons fire less during slow-wave sleep to recover from the “fatigue” accrued during wake, when overall synaptic activity is higher than in sleep. This idea, however, has rarely been tested and other factors, namely increased cortical synchrony, could explain why sleep slow-wave activity (SWA) is higher after extended wake. We forced neurons in the mouse cortex to fire at high levels for 6 h in 2 different conditions: during active wake with exploration and during sleep. We find that neurons need more time OFF only after sustained firing in wake, suggesting that fatigue due to sustained firing alone is unlikely to account for the increase in SWA that follows sleep deprivation. PMID:27927960

Why Does Sleep Slow-Wave Activity Increase After Extended Wake? Assessing the Effects of Increased Cortical Firing During Wake and Sleep.

PubMed

Rodriguez, Alexander V; Funk, Chadd M; Vyazovskiy, Vladyslav V; Nir, Yuval; Tononi, Giulio; Cirelli, Chiara

2016-12-07

During non-rapid eye movement (NREM) sleep, cortical neurons alternate between ON periods of firing and OFF periods of silence. This bi-stability, which is largely synchronous across neurons, is reflected in the EEG as slow waves. Slow-wave activity (SWA) increases with wake duration and declines homeostatically during sleep, but the underlying mechanisms remain unclear. One possibility is neuronal "fatigue": high, sustained firing in wake would force neurons to recover with more frequent and longer OFF periods during sleep. Another possibility is net synaptic potentiation during wake: stronger coupling among neurons would lead to greater synchrony and therefore higher SWA. Here, we obtained a comparable increase in sustained firing (6 h) in cortex by: (1) keeping mice awake by exposure to novel objects to promote plasticity and (2) optogenetically activating a local population of cortical neurons at wake-like levels during sleep. Sleep after extended wake led to increased SWA, higher synchrony, and more time spent OFF, with a positive correlation between SWA, synchrony, and OFF periods. Moreover, time spent OFF was correlated with cortical firing during prior wake. After local optogenetic stimulation, SWA and cortical synchrony decreased locally, time spent OFF did not change, and local SWA was not correlated with either measure. Moreover, laser-induced cortical firing was not correlated with time spent OFF afterward. Overall, these results suggest that high sustained firing per se may not be the primary determinant of SWA increases observed after extended wake. A long-standing hypothesis is that neurons fire less during slow-wave sleep to recover from the "fatigue" accrued during wake, when overall synaptic activity is higher than in sleep. This idea, however, has rarely been tested and other factors, namely increased cortical synchrony, could explain why sleep slow-wave activity (SWA) is higher after extended wake. We forced neurons in the mouse cortex to fire at high levels for 6 h in 2 different conditions: during active wake with exploration and during sleep. We find that neurons need more time OFF only after sustained firing in wake, suggesting that fatigue due to sustained firing alone is unlikely to account for the increase in SWA that follows sleep deprivation. Copyright © 2016 the authors 0270-6474/16/3612436-12$15.00/0.

Tracking Effects of Problematic Social Networking on Adolescent Psychopathology: The Mediating Role of Sleep Disruptions.

PubMed

Vernon, Lynette; Modecki, Kathryn L; Barber, Bonnie L

2017-01-01

Concerns are growing about adolescents' problematic social networking and possible links to depressed mood and externalizing behavior. Yet there remains little understanding of underlying processes that may account for these associations, including the mediating role of sleep disruption. This study tests this putative mediating process and examines change in problematic social networking investment and disrupted sleep, in relation to change in depressed mood and externalizing behavior. A sample of 874 students (41% male; 57.2% Caucasian; baseline M age = 14.4 years) from 27 high schools were surveyed. Participants' problematic social networking, sleep disruption, and psychopathology (depressed mood, externalizing behaviors) were measured annually over 3 years. Longitudinal mediation was tested using latent trajectories of problematic social networking use, sleep disruption, and psychopathology. Both problematic social networking and sleep disruption underwent positive linear growth over time. Adolescents who increasingly invested in social networking reported increased depressed mood, with around 53% of this association explained by the indirect effect of increased sleep disruptions. Further, adolescents who increasingly invested in social networking also reported increased externalizing behavior; some of this relation was explained (13%) via increased sleep disruptions. However an alternative model in which increased externalizing was associated with increased social networking, mediated by sleep disruptions, indicated a reciprocal relation of similar magnitude. It is important for parents, teachers, and psychologists to minimize the negative effects of social networking on adolescents' psychopathology. Interventions should potentially target promoting healthy sleep habits through reductions in social networking investment and rescheduling usage away from bedtime.

[Sleep deprivation and its effect on the ability to maintain wakefulness: implications on functioning and driving].

PubMed

Furman, Gabriela Dorfman; Cahan, Clement; Baharav, Armada

2009-05-01

During the last century, western society suffers from an increasing steep debt. A large number of accidents occur due to drowsy drivers. People are not aware of the influence of fatigue/drowsiness on their functioning and driving capacity. Our goal is to identify and characterize measurable physioLogicaL information capable of monitoring simple and reliable performance of driver vigilance. Eight healthy volunteers without sleep disorders were included in the study. They participated in two missions, on and off every two hours during 34-36 hours, in order to create an accumulative sleep debt. The tasks included the Maintenance of wakefulness test (MWT) and the driving simulator test. White tested, they remained connected to EEG, EMG, EOG, ECG and audio-video registration. These first results are related to 60 MWT tests. The first falling asleep events (FA) appeared around the early afternoon hours, in agreement to the physiological tendency to fall asleep, according to the biological clock. The night was characterized by FAs with a very short sleep Latency time at around 4 AM. On the second day of the experiment, the averaged sleep latency was larger than in the night before, despite the accumulation of sleep debt. The fluctuations of RRI increased after the first micro sleep. The autonomic nervous regulation displays an increase in the overall sympathetic activity as an indicator of increased stress. There is a correlation between parameters associated with instantaneous autonomic changes of heart rhythm (RRI) and the FA/almost-FA events observed on EEG. These attributes may provide a useful tool for monitoring drowsy drivers and preventing accidents.

Sleep duration and cancer risk: time to use a "sleep-years" index?

PubMed

Erren, Thomas C

2012-09-01

With a focus on melatonin, a recent paper in the Journal investigated the hypothesis that endometrial cancer might be associated with the duration, and ultimately, amount of sleep. The authors found that "[s]elf-reported sleep duration may not adequately represent melatonin levels." The authors also concluded that there was "weak evidence of an association between sleep duration and endometrial cancer risk." Overall, these are interesting observations because primarily experimental and mechanistic research from many angles supports the study's notion that inappropriate sleep may be a determinant of cancer risk. To find out whether this is so in man, rather than assigning study individuals to fixed or average "baseline sleep categories" i.e., ≤5, 6, 7, 8, ≥9 h of habitual sleep in the present study, the accumulated amount of sleep over decades should be reconstructed in retrospective or constructed in prospective studies. To achieve this end, future epidemiological studies may want to use a sleep-years index [SYI]. This simple exposure parameter promises to be a sensible, feasible, and affordable way to approximate cumulative time spent at sleep in critical time windows over many years which we should expect to be relevant for the development of cancer. The SYI could be tested and used in observational studies which promise to be comparable and can be merged. This commentary provides roots of the index and explains why and how it should be used and how it could be interpreted in rigorous studies of biologically plausible links between sleep, on the one hand, and the development of internal cancers, on the other. This commentary also points out limitations of interpreting the SYI. It is emphasized that, where possible, the SYI should be assessed independently of (a) other sleep facets--such as quality--and of (b) known or suspected cancer risk factors. The respective contribution of (a) and (b) to risk must then be assessed during the analyses. Overall, the suggested inclusion and standardization of assessing sleep duration could be an important step forward when evaluating possible cancer risks in relation to sleep. Finally, the proposed approach may prove useful beyond sleep epidemiology per se: to exemplify, research into suggested causal links between disrupted natural sleep-wakefulness cycles and increased cancer risks in shift-workers could also benefit.

The effects of nitric oxide synthase inhibitors on the sedative effect of clonidine.

PubMed

Soares de Moura, R; Rios, A A; de Oliveira, L F; Resende, A C; de Lemos Neto, M; Santos, E J; Correia, M L; Tano, T

2001-11-01

The mechanism underlying the Niteroi, Rio de Janeiro sedative effect of clonidine, an alpha2-adrenoceptor agonist, remains uncertain. Because activation of alpha2-adrenoceptors induces release of nitric oxide (NO), we tested the hypothesis that the sedative effect of clonidine depends on NO-related mechanisms. The effect of 7-nitro indazole on the sleeping time induced by clonidine was studied in Wistar rats. In addition, we examined the effect of clonidine, alpha-methyldopa, and midazolam on the thiopental-induced sleeping time in rats pretreated with N(G)-nitro-L-arginine-methyl-ester (L-NAME). The sleeping time induced by clonidine was significantly decreased by 7-nitro indazole. Thiopental sleeping time was increased by clonidine, alpha-methyldopa, and midazolam. L-NAME reduced the prolongation effect of clonidine and alpha-methyldopa, but did not alter the effect of midazolam on the thiopental-induced sleeping time. The inhibitory effect of L-NAME on clonidine-dependent prolongation of thiopental-induced sleeping time was reversed by L-arginine. These results suggest that NO-dependent mechanisms are involved in the sedative effect of clonidine. In addition, this effect seems to be specific for the sedative action of alpha2-adrenoceptors agonists. Clonidine, an antihypertensive drug, is also a sedative. This sedative effect, although an adverse event in the treatment of hypertensive patients, can be helpful for sedation of surgical patients. The mechanism of this effect, however, is unknown. In this study, we show that the sedative effect of clonidine is mediated by nitric oxide, because it could be prevented by pretreatment with nitric oxide synthase inhibitors.

Bedtime and sleep timing but not sleep duration are associated with eating habits in primary school children.

PubMed

Thivel, David; Isacco, Laurie; Aucouturier, Julien; Pereira, Bruno; Lazaar, Nordine; Ratel, Sébastien; Doré, Eric; Duché, Pascale

2015-04-01

In the context of childhood obesity progression, sleep patterns have been associated with unhealthy eating habits and energy intake. The association between several eating habits and sleep patterns in children has been recently studied. The aim of this study was to explore the association between sleep patterns, eating habits, and physical fitness in primary school children. A total of 236 children of 6 to 10 years old were recruited. Anthropometric characteristics and body composition were measured, and cardiorespiratory (20-m shuttle run test) and musculoskeletal (squat jump and cycling peak power) fitness tests were performed. Parents were asked to fill out an eating habits questionnaire, and children were classified into 4 categories as a function of the number of eating risk factors they presented. Parents completed a questionnaire about their child's bedtime and waking hours during weekdays and weekends. Weight (p < .01), waist circumference, and fat mass (p < .05) were significantly higher in late sleepers (27.6 ± 6.3 kg; 60.1 ± 7.6 cm; 19.52 ± 7.44) compared with normal sleepers (25.4 ± 3.7 kg; 58.2 ± 4.9 cm; 17.44% ± 6.23%). None of the physical fitness parameters were associated with sleep duration, bedtime, wake-up time, nor were they significantly different between late and normal sleepers. Bedtime was significantly earlier in children consuming breakfast everyday (08:30 vs. 09:00 PM, p < .01); later in children snacking (09:15 vs. 09:30 PM, p < .05) or watching TV at lunch (10:00 vs 09:30 PM, p < .05). There is an association between the proportion of normal and late sleepers and the accumulation of healthy eating habits (p < .001). Bedtime and sleep timings (normal or late sleepers) are associated with eating habits in primary school children. It seems necessary to consider the number of unhealthy eating habits adopted by children when studying these associations.

Hypersomnia.

PubMed

Dauvilliers, Yves; Buguet, Alain

2005-01-01

Hypersomnia, a complaint of excessive daytime sleep or sleepiness, affects 4% to 6% of the population, with an impact on the everyday life of the patient Methodological tools to explore sleep and wakefulness (interview, questionnaires, sleep diary, polysomnography, Multiple Sleep Latency Test, Maintenance of Wakefulness Test) and psychomotor tests (for example, psychomotor vigilance task and Oxford Sleep Resistance or Osler Test) help distinguish between the causes of hypersomnia. In this article, the causes of hypersomnia are detailed following the conventional classification of hypersomnic syndromes: narcolepsy, idiopathic hypersomnia, recurrent hypersomnia, insufficient sleep syndrome, medication- and toxin-dependent sleepiness, hypersomnia associated with psychiatric disorders, hypersomnia associated with neurological disorders, posttraumatic hypersomnia, infection (with a special emphasis on the differences between bacterial and viral diseases compared with parasitic diseases, such as sleeping sickness) and hypersomnia, hypersomnia associated with metabolic or endocrine diseases, breathing-related sleep disorders and sleep apnea syndromes, and periodic limb movements in sleep.

Hypersomnia

PubMed Central

Dauvilliers, Yves; Buguet, Alain

2005-01-01

Hypersomnia, a complaint of excessive daytime sleep or sleepiness, affects 4% to 6% of the population, with an impact on the everyday life of the patient Methodological tools to explore sleep and wakefulness (interview, questionnaires, sleep diary, polysomnography Multiple Sleep Latency Test, Maintenance of Wakefulness Test) and psy-chomotor tests (for example, psychomotor vigilance task and Oxford Sleep Resistance or Osier Test) help distinguish between the causes of hypersomnia. In this article, the causes of hypersomnia are detailed following the conventional classification of hypersomnic syndromes: narcolepsy, idiopathic hypersomnia, recurrent hypersomnia, insufficient sleep syndrome, medication- and toxin-dependent sleepiness, hypersomnia associated with psychiatric disorders, hypersomnia associated with neurological disorders, posttraumatic hypersomnia, infection (with a special emphasis on the differences between bacterial and viral diseases compared with parasitic diseases, such as sleeping sickness) and hypersomnia, hypersomnia associated with metabolic or endocrine diseases, breathing-related sleep disorders and sleep apnea syndromes, and periodic limb movements in sleep. PMID:16416710

Modafinil in the treatment of idiopathic hypersomnia without long sleep time--a randomized, double-blind, placebo-controlled study.

PubMed

Mayer, Geert; Benes, Heike; Young, Peter; Bitterlich, Marion; Rodenbeck, Andrea

2015-02-01

In 2010 the European Medicines Agency withdrew the indication of modafinil for the treatment of obstructive sleep apnea, shift work sleep disorder and for idiopathic hypersomnia (IH). In uncontrolled studies, modafinil has been reported to be efficacious in the treatment of sleep disorders. We therefore performed a randomized, placebo-controlled study with the aim of proving the efficacy of modafinil treatment in these patients. Drug-free IH patients without long sleep according to ICSD2 criteria, age >18 years and disease duration >2 years were included. After a washout phase, patients at baseline received placebo or 100 mg modafinil in the morning and at noon over 3 weeks, followed by 1 week without medication. At each visit the Epworth Sleepiness Scale (ESS) and Clinical Global Impression (CGI) rating scale were performed. At baseline and on days 8 and 21 four Maintenance of Wakefulness Tests (MWTs)/day or per day were performed. Patients kept a sleep-wake diary throughout the study. Between 2009 and 2011 three sleep centres recruited 33 participants. Compared to placebo, modafinil decreased sleepiness significantly and improved mean sleep latency in the MWT non-significantly. The CGI improved significantly from baseline to the last visit on treatment. The most frequent adverse events were headaches and gastrointestinal disorders; skin and psychiatric reactions were not reported. The number of reported naps and duration of daytime sleepiness decreased significantly. Total sleep time of nocturnal sleep was slightly reduced. The sleep diaries showed increases in feeling refreshed in the morning; the diurnal diaries showed significant improvement of performance and of exhaustion. Modafinil is an effective and safe medication in the treatment of IH. Adverse events are mild to moderate. © 2014 European Sleep Research Society.

Dexmedetomidine-induced sedation does not mimic the neurobehavioral phenotypes of sleep in Sprague Dawley rat.

PubMed

Garrity, Abigail G; Botta, Simhadri; Lazar, Stephanie B; Swor, Erin; Vanini, Giancarlo; Baghdoyan, Helen A; Lydic, Ralph

2015-01-01

Dexmedetomidine is used clinically to induce states of sedation that have been described as homologous to nonrapid eye movement (NREM) sleep. A better understanding of the similarities and differences between NREM sleep and dexmedetomidine-induced sedation is essential for efforts to clarify the relationship between these two states. This study tested the hypothesis that dexmedetomidine-induced sedation is homologous to sleep. This study used between-groups and within-groups designs. University of Michigan. Adult male Sprague Dawley rats (n = 40). Independent variables were administration of dexmedetomidine and saline or Ringer's solution (control). Dependent variables included time spent in states of wakefulness, sleep, and sedation, electroencephalographic (EEG) power, adenosine levels in the substantia innominata (SI), and activation of pCREB and c-Fos in sleep related forebrain regions. Dexmedetomidine significantly decreased time spent in wakefulness (-49%), increased duration of sedation (1995%), increased EEG delta power (546%), and eliminated the rapid eye movement (REM) phase of sleep for 16 h. Sedation was followed by a rebound increase in NREM and REM sleep. Systemically administered dexmedetomidine significantly decreased (-39%) SI adenosine levels. Dialysis delivery of dexmedetomidine into SI did not decrease adenosine level. Systemic delivery of dexmedetomidine did not alter c-Fos or pCREB expression in the horizontal diagonal band, or ventrolateral, median, and medial preoptic areas of the hypothalamus. Dexmedetomidine significantly altered normal sleep phenotypes, and the dexmedetomidine-induced state did not compensate for sleep need. Thus, in the Sprague Dawley rat, dexmedetomidine-induced sedation is characterized by behavioral, electrographic, and immunohistochemical phenotypes that are distinctly different from similar measures obtained during sleep. © 2014 Associated Professional Sleep Societies, LLC.

Impaired quality and efficiency of sleep impairs cognitive functioning in Addison's disease.

PubMed

Henry, Michelle; Ross, Ian Louis; Wolf, Pedro Sofio Abril; Thomas, Kevin Garth Flusk

2017-04-01

Standard replacement therapy for Addison's disease (AD) does not restore a normal circadian rhythm. Periods of sub- and supra- physiological cortisol levels experienced by patients with AD likely induce disrupted sleep. Given that healthy sleep plays an important role in memory consolidation, the novelty of the current study was to characterise, using objective measures, the relationship between sleep and memory in patients with AD, and to examine the hypothesis that poor sleep is a biological mechanism underlying memory impairment in those patients. We used a within-subjects design. Ten patients with AD and 10 matched healthy controls completed standardised neuropsychological tests assessing declarative memory (Rey Auditory Verbal Learning Test) and procedural memory (Finger Tapping Task) before and after a period of actigraphy-measured sleep, and before and after a period of waking. Relative to healthy controls, patients with AD experienced disrupted sleep characterised by poorer sleep efficiency and more time spent awake. Patients also showed impaired verbal learning and memory relative to healthy controls (p=0.007). Furthermore, whereas healthy controls' declarative memory performance benefited from a period of sleep compared to waking (p=0.032), patients with AD derived no such benefit from sleep (p=0.448). Regarding the procedural memory task, analyses detected no significant between-group differences (all p's<0.065), and neither group showed significant sleep-enhanced performance. We demonstrated, using actigraphy and standardized measures of memory performance, an association between sleep disturbances and cognitive deficits in patients with AD. These results suggest that, in patients with AD, the source of memory deficits is, at least to some extent, disrupted sleep patterns that interfere with optimal consolidation of previously-learned declarative information. Hence, treating the sleep disturbances that are frequently experienced by patients with AD may improve their cognitive functioning. Copyright © 2017 Elsevier Ltd. All rights reserved.

Restless Legs Syndrome -- Self-Tests and Diagnosis

MedlinePlus

... Overview & Facts Symptoms & Causes Diagnosis & Self Tests Treatment Sleep Apnea Overview & Facts Symptoms & Risk Factors Self-Tests Diagnosis ... for a Sleep Study Testing Process & Results Home Sleep Apnea Testing Overview Testing Process & Results CPAP Overview Benefits ...

Increased Automaticity and Altered Temporal Preparation Following Sleep Deprivation.

PubMed

Kong, Danyang; Asplund, Christopher L; Ling, Aiqing; Chee, Michael W L

2015-08-01

Temporal expectation enables us to focus limited processing resources, thereby optimizing perceptual and motor processing for critical upcoming events. We investigated the effects of total sleep deprivation (TSD) on temporal expectation by evaluating the foreperiod and sequential effects during a psychomotor vigilance task (PVT). We also examined how these two measures were modulated by vulnerability to TSD. Three 10-min visual PVT sessions using uniformly distributed foreperiods were conducted in the wake-maintenance zone the evening before sleep deprivation (ESD) and three more in the morning following approximately 22 h of TSD. TSD vulnerable and nonvulnerable groups were determined by a tertile split of participants based on the change in the number of behavioral lapses recorded during ESD and TSD. A subset of participants performed six additional 10-min modified auditory PVTs with exponentially distributed foreperiods during rested wakefulness (RW) and TSD to test the effect of temporal distribution on foreperiod and sequential effects. Sleep laboratory. There were 172 young healthy participants (90 males) with regular sleep patterns. Nineteen of these participants performed the modified auditory PVT. Despite behavioral lapses and slower response times, sleep deprived participants could still perceive the conditional probability of temporal events and modify their level of preparation accordingly. Both foreperiod and sequential effects were magnified following sleep deprivation in vulnerable individuals. Only the foreperiod effect increased in nonvulnerable individuals. The preservation of foreperiod and sequential effects suggests that implicit time perception and temporal preparedness are intact during total sleep deprivation. Individuals appear to reallocate their depleted preparatory resources to more probable event timings in ongoing trials, whereas vulnerable participants also rely more on automatic processes. © 2015 Associated Professional Sleep Societies, LLC.

Gratitude influences sleep through the mechanism of pre-sleep cognitions.

PubMed

Wood, Alex M; Joseph, Stephen; Lloyd, Joanna; Atkins, Samuel

2009-01-01

To test whether individual differences in gratitude are related to sleep after controlling for neuroticism and other traits. To test whether pre-sleep cognitions are the mechanism underlying this relationship. A cross-sectional questionnaire study was conducted with a large (186 males, 215 females) community sample (ages=18-68 years, mean=24.89, S.D.=9.02), including 161 people (40%) scoring above 5 on the Pittsburgh Sleep Quality Index, indicating clinically impaired sleep. Measures included gratitude, the Pittsburgh Sleep Quality Index (PSQI), self-statement test of pre-sleep cognitions, the Mini-IPIP scales of Big Five personality traits, and the Social Desirability Scale. Gratitude predicted greater subjective sleep quality and sleep duration, and less sleep latency and daytime dysfunction. The relationship between gratitude and each of the sleep variables was mediated by more positive pre-sleep cognitions and less negative pre-sleep cognitions. All of the results were independent of the effect of the Big Five personality traits (including neuroticism) and social desirability. This is the first study to show that a positive trait is related to good sleep quality above the effect of other personality traits, and to test whether pre-sleep cognitions are the mechanism underlying the relationship between any personality trait and sleep. The study is also the first to show that trait gratitude is related to sleep and to explain why this occurs, suggesting future directions for research, and novel clinical implications.

Sleep Duration and Its Association With Ambulatory Blood Pressure in a School-Based, Diverse Sample of Adolescents

PubMed Central

Gallagher, Martina R.; Eissa, Mona A.; Nguyen, Thong Q.; Chan, Wenyaw

2014-01-01

BACKGROUND Evidence is accumulating that sleep duration is related to blood pressure (BP) and hypertensive status, but the strength of the association varies by age, and findings are inconsistent for adolescents. This cross-sectional study tested the hypothesis that sleep duration, both during the night and during naps, would be negatively associated with ambulatory systolic BP (SBP) and diastolic BP (DBP) measured over 24 hours in adolescents. METHODS In this ethnically diverse (37% non-Hispanic black, 31% Hispanic, 29% non-Hispanic white, 3% other), school-based sample of 366 adolescents aged 11–16 years, ambulatory BP was measured every 30 minutes for 24 hours on a school day; actigraphy was used to measure sleep duration. Covariables included demographic factors, anthropometric indices, physical activity, and position and location at the time of each BP measurement. Mixed models were used to test day and night sleep duration as predictors of 24-hour SBP and DBP, controlling for covariables. RESULTS The mean sleep duration was 6.83 (SD = 1.36) hours at night, and 7.23 (SD = 1.67) hours over 24 hours. Controlling for duration of sleep during the day and covariables, each additional hour of nighttime sleep was associated with lower SBP (−0.57; P < 0.0001); controlling for nighttime sleep duration and covariables, each additional hour of daytime sleep was associated with lower SBP (−0.73; P < 0.001) and lower DBP (−0.50; P < 0.001). CONCLUSIONS Longer sleep duration was significantly associated with lower ambulatory SBP and DBP in adolescents. The findings have potential implications for cardiovascular health in this age group. PMID:24487981

Slow Wave Sleep Enhancement with Gaboxadol Reduces Daytime Sleepiness During Sleep Restriction

PubMed Central

Walsh, James K.; Snyder, Ellen; Hall, Janine; Randazzo, Angela C.; Griffin, Kara; Groeger, John; Eisenstein, Rhody; Feren, Stephen D.; Dickey, Pam; Schweitzer, Paula K.

2008-01-01

Study Objectives: To evaluate the impact of enhanced slow wave sleep (SWS) on behavioral, psychological, and physiological changes resulting from sleep restriction. Design: A double-blind, parallel group, placebo-controlled design was used to compare gaboxadol (GBX) 15 mg, a SWS-enhancing drug, to placebo during 4 nights of sleep restriction (5 h/night). Behavioral, psychological, and physiological measures of the impact of sleep restriction were assessed in both groups at baseline, during sleep restriction and following recovery sleep. Setting: Sleep research laboratory. Participants: Forty-one healthy adults; 9 males and 12 females (mean age: 32.0 ± 9.9 y) in the placebo group and 10 males and 10 females (mean age: 31.9 ± 10.2 y) in the GBX group. Interventions: Both experimental groups underwent 4 nights of sleep restriction. Each group received either GBX 15 mg or placebo on all sleep restriction nights, and both groups received placebo on baseline and recovery nights. Measurements and Results: Polysomnography documented a SWS-enhancing effect of GBX with no group difference in total sleep time during sleep restriction. The placebo group displayed the predicted deficits due to sleep restriction on the multiple sleep latency test (MSLT) and on introspective measures of sleepiness and fatigue. Compared to placebo, the GBX group showed significantly less physiological sleepiness on the MSLT and lower levels of introspective sleepiness and fatigue during sleep restriction. There were no differences between groups on the psychomotor vigilance task (PVT) and a cognitive test battery, but these measures were minimally affected by sleep restriction in this study. The correlation between change from baseline in MSLT on Day 6 and change from baseline in SWS on Night 6 was significant in the GBX group and in both groups combined. Conclusions: The results of this study are consistent with the hypothesis that enhanced SWS, in this study produced by GBX, reduces physiological sleep tendency and introspective sleepiness and fatigue which typically result from sleep restriction. Citation: Walsh JK; Snyder E; Hall J; Randazzo AC; Griffin K; Groeger J; Eisenstein R; Feren SD; Dickey P; Schweitzer PK. Slow Wave Sleep Enhancement with Gaboxadol Reduces Daytime Sleepiness During Sleep Restriction. SLEEP 2008;31(5):659–672. PMID:18517036

Acupuncture for treatment of insomnia in patients with traumatic brain injury: a pilot intervention study.

PubMed

Zollman, Felise S; Larson, Eric B; Wasek-Throm, Laura K; Cyborski, Cherina M; Bode, Rita K

2012-01-01

: To assess the efficacy of acupuncture in treating insomnia in traumatic brain injury (TBI) survivors as compared to medication, to determine whether acupuncture has fewer cognitive and affective adverse effects than does medication. : Twenty-four adult TBI survivors, randomized to acupuncture or control arms. : Outpatient rehabilitation clinic. : Insomnia Severity Index (degree of insomnia); actigraphy (sleep time); Hamilton Depression Rating Scale (depression); Repeatable Battery for the Assessment of Neuropsychological Status and Paced Auditory Serial Addition Test (cognitive function) administered at baseline and postintervention. : Sleep time did not differ between the treatment and control groups after intervention, whereas cognition improved in the former but not the latter. : Acupuncture has a beneficial effect on perception of sleep or sleep quality and on cognition in our small sample of patients with TBI. Further studies of this treatment modality are warranted to validate these findings and to explore factors that contribute to treatment efficacy.

Sleep Dependent Memory Consolidation in Children with Autism Spectrum Disorder.

PubMed

Maski, Kiran; Holbrook, Hannah; Manoach, Dara; Hanson, Ellen; Kapur, Kush; Stickgold, Robert

2015-12-01

Examine the role of sleep in the consolidation of declarative memory in children with autism spectrum disorder (ASD). Case-control study. Home-based study with sleep and wake conditions. Twenty-two participants with ASD and 20 control participants between 9 and 16 y of age. Participants were trained to criterion on a spatial declarative memory task and then given a cued recall test. Retest occurred after a period of daytime wake (Wake) or a night of sleep (Sleep) with home-based polysomnography; Wake and Sleep conditions were counterbalanced. Children with ASD had poorer sleep efficiency than controls, but other sleep macroarchitectural and microarchitectural measures were comparable after controlling for age and medication use. Both groups demonstrated better memory consolidation across Sleep than Wake, although participants with ASD had poorer overall memory consolidation than controls. There was no interaction between group and condition. The change in performance across sleep, independent of medication and age, showed no significant relationships with any specific sleep parameters other than total sleep time and showed a trend toward less forgetting in the control group. This study shows that despite their more disturbed sleep quality, children with autism spectrum disorder (ASD) still demonstrate more stable memory consolidation across sleep than in wake conditions. The findings support the importance of sleep for stabilizing memory in children with and without neurodevelopmental disabilities. Our results suggest that improving sleep quality in children with ASD could have direct benefits to improving their overall cognitive functioning. © 2015 Associated Professional Sleep Societies, LLC.

Involvement of the α1-adrenoceptor in sleep-waking and sleep loss-induced anxiety behavior in zebrafish.

PubMed

Singh, A; Subhashini, N; Sharma, S; Mallick, B N

2013-08-15

Sleep is a universal phenomenon in vertebrates, and its loss affects various behaviors. Independent studies have reported that sleep loss increases anxiety; however, the detailed mechanism is unknown. Because sleep deprivation increases noradrenalin (NA), which modulates many behaviors and induces patho-physiological changes, this study utilized zebrafish as a model to investigate whether sleep loss-induced increased anxiety is modulated by NA. Continuous behavioral quiescence for at least 6s was considered to represent sleep in zebrafish; although some authors termed it as a sleep-like state, in this study we have termed it as sleep. The activity of fish that signified sleep-waking was recorded in light-dark, during continuous dark and light; the latter induced sleep loss in fish. The latency, number of entries, time spent and distance travelled in the light chamber were assessed in a light-dark box test to estimate the anxiety behavior of normal, sleep-deprived and prazosin (PRZ)-treated fish. Zebrafish showed increased waking during light and complete loss of sleep upon continuous exposure to light for 24h. PRZ significantly increased sleep in normal fish. Sleep-deprived fish showed an increased preference for dark (expression of increased anxiety), and this effect was prevented by PRZ, which increased sleep as well. Our findings suggest that sleep loss-induced anxiety-like behavior in zebrafish is likely to be mediated by NA's action on the α1-adrenoceptor. Copyright © 2013 IBRO. Published by Elsevier Ltd. All rights reserved.

Genetic and environmental contributions to sleep-wake behavior in 12-year-old twins.

PubMed

Sletten, Tracey L; Rajaratnam, Shantha M W; Wright, Margaret J; Zhu, Gu; Naismith, Sharon; Martin, Nicholas G; Hickie, Ian

2013-11-01

To examine the role of genetic and environmental factors on sleep behavior in 12-year-old twins matched for family environment. Population-based twin cohort. Participants were assessed in their home environment. One hundred thirty-two adolescent twins comprising 25 monozygotic (MZ) and 41 dizygotic (DZ) twin pairs; aged 12.2 ± 0.1 y (mean ± standard deviation). N/A. For 2 weeks in their home environment, participants wore a wrist activity monitor and completed a daily sleep diary. Sleep diaries included reports of bedtime, wake time, and estimated sleep onset time. Mean timing, duration, and quality of sleep during the 2 weeks were calculated for each individual and compared within twin pairs. MZ twin correlations were higher than the DZ correlations for total sleep time (MZr = 0.64; DZr = 0.38) and sleep onset latency (MZr = 0.83; DZr = 0.53) and significantly higher for wake after sleep onset (MZr = 0.66; DZr = 0.04) and sleep efficiency (MZr = 0.82; DZr = 0.10). Univariate modeling showed additive genetic factors accounted for 65% of the variance in total sleep time, 83% in sleep onset latency, and 52% and 57% of the variance in wake after sleep onset and sleep efficiency, respectively. A predominant influence of shared environment was found on the timing of sleep (67% for sleep start time, 86% for sleep end time). There is a strong genetic influence on the sleep-wake patterns of 12-year-old adolescents. Genes have a greater influence on sleep initiation and sleep maintenance and a smaller role in sleep timing, likely to be influenced by family environment.

Infant Growth in Length Follows Prolonged Sleep and Increased Naps

PubMed Central

Lampl, Michelle; Johnson, Michael L.

2011-01-01

Study Objectives: The mechanisms underlying infant sleep irregularity are unknown. This study tests the hypothesis that sleep and episodic (saltatory) growth in infant length are temporally coupled processes. Study design: Daily parental diaries continuously recorded sleep onset and awakening for 23 infants (14 females) over 4-17 months (n = 5798 daily records). Multiple model-independent methods compared day-to-day sleep patterns and saltatory length growth. Measurements and Results: Approximate entropy (ApEn) quantified temporal irregularity in infant sleep patterns; breastfeeding and infant sex explained 44% of inter-individual variance (P = 0.001). Random effects mixed-model regression identified that saltatory length growth was associated with increased total daily sleep hours (P < 0.001) and number of sleep bouts (P = 0.001), with breastfeeding, infant sex, and age as covariates. Infant size and illness onset were non-contributory. CLUSTER analysis identified peaks in individual sleep of 4.5 more h and/or 3 more naps per day, compared to intervening intervals, that were non-randomly concordant with saltatory length growth for all individuals (P < 0.05), with a time lag of 0-4 days. Subject-specific probabilities of a growth saltation associated with sleep included a median odds ratio of 1.20 for each additional hour (n = 8, 95% CI 1.15 to 1.29) and 1.43 for each additional sleep bout (n = 12, 95% CI 1.21-2.03). Increased sleep bout duration predicted weight (P < 0.001) and abdominal skinfold accrual (P = 0.05) contingent on length growth, and truncal adiposity independent of growth (P < 0.001). Conclusions: Sleeping and length growth are temporally related biological processes, suggesting an integrated anabolic system. Infant behavioral state changes may reflect biological mechanisms underlying the timing and control of human growth. Citation: Lampl M; Johnson ML. Infant growth in length follows prolonged sleep and increased naps. SLEEP 2011;34(5):641-650. PMID:21532958

24 Hours of Sleep, Sedentary Behavior, and Physical Activity with Nine Wearable Devices

PubMed Central

Rosenberger, Mary E.; Buman, Matthew P.; Haskell, William L.; McConnell, Michael V.; Carstensen, Laura L.

2015-01-01

Getting enough sleep, exercising and limiting sedentary activities can greatly contribute to disease prevention and overall health and longevity. Measuring the full 24-hour activity cycle - sleep, sedentary behavior (SED), light intensity physical activity (LPA) and moderate-to-vigorous physical activity (MVPA) - may now be feasible using small wearable devices. PURPOSE This study compares nine devices for accuracy in 24-hour activity measurement. METHODS Adults (N=40, 47% male) wore nine devices for 24-hours: Actigraph GT3X+, activPAL, Fitbit One, GENEactiv, Jawbone Up, LUMOback, Nike Fuelband, Omron pedometer, and Z-Machine. Comparisons (to standards) were made for total sleep time (Z-machine), time spent in SED (activPAL), LPA (GT3x+), MVPA (GT3x+), and steps (Omron). Analysis included mean absolute percent error, equivalence testing, and Bland-Altman plots. RESULTS Error rates ranged from 8.1–16.9% for sleep; 9.5–65.8% for SED; 19.7–28.0% for LPA; 51.8–92% for MVPA; and 14.1–29.9% for steps. Equivalence testing indicated only two comparisons were significantly equivalent to standards: the LUMOback for sedentary behavior and the GT3X+ for sleep. Bland-Altman plots indicated GT3X+ had the closest measurement for sleep, LUMOback for sedentary behavior, GENEactiv for LPA, Fitbit for MVPA and GT3X+ for steps. CONCLUSIONS Currently, no device accurately captures activity data across the entire 24-hour day, but the future of activity measurement should aim for accurate 24-hour measurement as a goal. Researchers should continue to select measurement devices based on their primary outcomes of interest. PMID:26484953

Twenty-four Hours of Sleep, Sedentary Behavior, and Physical Activity with Nine Wearable Devices.

PubMed

Rosenberger, Mary E; Buman, Matthew P; Haskell, William L; McConnell, Michael V; Carstensen, Laura L

2016-03-01

Getting enough sleep, exercising, and limiting sedentary activities can greatly contribute to disease prevention and overall health and longevity. Measuring the full 24-h activity cycle-sleep, sedentary behavior (SED), light-intensity physical activity (LPA), and moderate-to-vigorous physical activity (MVPA)-may now be feasible using small wearable devices. This study compared nine devices for accuracy in a 24-h activity measurement. Adults (n = 40, 47% male) wore nine devices for 24 h: ActiGraph GT3X+, activPAL, Fitbit One, GENEactiv, Jawbone Up, LUMOback, Nike Fuelband, Omron pedometer, and Z-Machine. Comparisons (with standards) were made for total sleep time (Z-machine), time spent in SED (activPAL), LPA (GT3X+), MVPA (GT3X+), and steps (Omron). Analysis included mean absolute percent error, equivalence testing, and Bland-Altman plots. Error rates ranged from 8.1% to 16.9% for sleep, 9.5% to 65.8% for SED, 19.7% to 28.0% for LPA, 51.8% to 92% for MVPA, and 14.1% to 29.9% for steps. Equivalence testing indicated that only two comparisons were significantly equivalent to standards: the LUMOback for SED and the GT3X+ for sleep. Bland-Altman plots indicated GT3X+ had the closest measurement for sleep, LUMOback for SED, GENEactiv for LPA, Fitbit for MVPA, and GT3X+ for steps. Currently, no device accurately captures activity data across the entire 24-h day, but the future of activity measurement should aim for accurate 24-h measurement as a goal. Researchers should continue to select measurement devices on the basis of their primary outcomes of interest.

The Effects of Sleep Continuity Disruption on Positive Mood and Sleep Architecture in Healthy Adults.

PubMed

Finan, Patrick H; Quartana, Phillip J; Smith, Michael T

2015-11-01

The purpose of this study was to test an experimental model of the effects of sleep continuity disturbance on sleep architecture and positive mood in order to better understand the mechanisms linking insomnia and depression. Participants were randomized to receive 3 consecutive nights of sleep continuity disruption via forced nocturnal awakenings (FA, n = 21), or one of two control conditions: restricted sleep opportunity (RSO, n = 17) or uninterrupted sleep (US, n = 24). The study was set in an inpatient clinical research suite. Healthy, good-sleeping men and women were included. Polysomnography was used to measure sleep architecture, and mood was assessed via self-report each day. Compared to restricted sleep opportunity controls, forced awakenings subjects had significantly less slow wave sleep (P < 0.05) after the first night of sleep deprivation, and significantly lower positive mood (P < 0.05) after the second night of sleep deprivation. The differential change in slow wave sleep statistically mediated the observed group differences in positive mood (P = 0.002). To our knowledge, this is the first human experimental study to demonstrate that, despite comparable reductions in total sleep time, partial sleep loss from sleep continuity disruption is more detrimental to positive mood than partial sleep loss from delaying bedtime, even when controlling for concomitant increases in negative mood. With these findings, we provide temporal evidence in support of a putative biologic mechanism (slow wave sleep deficit) that could help explain the strong comorbidity between insomnia and depression. © 2015 Associated Professional Sleep Societies, LLC.

Sleep and gravity.

PubMed

Gonfalone, Alain A

2018-04-01

What is known about sleep results from years of observation at the surface of the Earth. Since a few decade man has been able to reach space, escape from the earth attraction and spend days and nights in a weightless condition. Some major physiological changes have been observed during long stays and in particular the sleep duration in space is shorter than on ground. This paper reviews a novel hypothesis proposing that sleep is partly due to gravity. Gravity is a fundamental part of our environment, but is elusive and difficult to apprehend. At the same time, all creatures on Earth undergo cycles of activity and periods of rest (although not always sleep). Careful analysis of previous research on sleep, on Earth, in space and in water, shows that gravity differs in these three situations, and sleep also varies, at least in its duration. On Earth, Rapid Eye Movement (REM) sleep is conditioned by gravity; in space, astronauts have a shorter sleep duration and this is even more striking when a test subject is immersed in water for a week. In conclusion, sleep is partly due to gravity, which acts on our body and brain during the wake period. Copyright © 2018 The Author. Published by Elsevier Ltd.. All rights reserved.

Greater Effect of East versus West Travel on Jet Lag, Sleep, and Team Sport Performance.

PubMed

Fowler, Peter M; Knez, Wade; Crowcroft, Stephen; Mendham, Amy E; Miller, Joanna; Sargent, Charlie; Halson, Shona; Duffield, Rob

2017-12-01

This study aimed to determine the recovery timeline of sleep, subjective jet lag and fatigue, and team sport physical performance after east and west long-haul travel. Ten physically trained men underwent testing at 0900 h and 1700 h local time on four consecutive days 2 wk before outbound travel (BASE), and the first 4 d after 21 h of outbound (WEST) and return (EAST) air travel across eight time zones between Australia and Qatar. Data collection included performance (countermovement jump, 20-m sprint, and Yo-Yo intermittent recovery level 1 [YYIR1] test) and perceptual (jet lag, motivation, perceived exertion, and physical feeling) measures. In addition, sleep was measured via wrist activity monitors and self-report diaries throughout the aforementioned data collection periods. Compared with the corresponding day at BASE, the reduction in YYIR1 distance after EAST was significantly different from the increase in WEST on day 1 after travel (P < 0.001). On day 2, significantly slower 20-m sprint times were detected in EAST compared with WEST (P = 0.03), with large effect sizes (ES) also indicating a greater reduction in YYIR1 distance in EAST compared with WEST (d = 1.06). Mean sleep onset and offset were significantly later and mean time in bed and sleep duration were significantly reduced across the 4 d in EAST compared with BASE and WEST (P < 0.05). Lastly, mean jet lag, fatigue, and motivation ratings across the 4 d were significantly worse in EAST compared with BASE and WEST (P < 0.05) and WEST compared with BASE (P < 0.05). Long-haul transmeridian travel can impede team sport physical performance. Specifically, east travel has a greater detrimental effect on sleep, subjective jet lag, fatigue, and motivation. Consequently, maximal and intermittent sprint performance is also reduced after east travel, particularly within 72 h after arrival.

How is good and poor sleep in older adults and college students related to daytime sleepiness, fatigue, and ability to concentrate?

PubMed

Alapin, I; Fichten, C S; Libman, E; Creti, L; Bailes, S; Wright, J

2000-11-01

We compared good sleepers with minimally and highly distressed poor sleepers on three measures of daytime functioning: self-reported fatigue, sleepiness, and cognitive inefficiency. In two samples (194 older adults, 136 college students), we tested the hypotheses that (1) poor sleepers experience more problems with daytime functioning than good sleepers, (2) highly distressed poor sleepers report greater impairment in functioning during the day than either good sleepers or minimally distressed poor sleepers, (3) daytime symptoms are more closely related to psychological adjustment and to psychologically laden sleep variables than to quantitative sleep parameters, and (4) daytime symptoms are more closely related to longer nocturnal wake times than to shorter sleep times. Results in both samples indicated that poor sleepers reported more daytime difficulties than good sleepers. While low- and high-distress poor sleepers did not differ on sleep parameters, highly distressed poor sleepers reported consistently more difficulty in functioning during the day and experienced greater tension and depression than minimally distressed poor sleepers. Severity of all three daytime problems was generally significantly and positively related to poor psychological adjustment, psychologically laden sleep variables, and, with the exception of sleepiness, to quantitative sleep parameters. Results are used to discuss discrepancies between experiential and quantitative measures of daytime functioning.

Actigraphic Sleep Duration and Fragmentation in Older Women: Associations With Performance Across Cognitive Domains.

PubMed

Spira, Adam P; Stone, Katie L; Redline, Susan; Ensrud, Kristine E; Ancoli-Israel, Sonia; Cauley, Jane A; Yaffe, Kristine

2017-08-01

To determine the association of actigraphic sleep duration and fragmentation with cognition in community-dwelling older women. We studied 782 women (mean age = 87.4) of varied cognitive status from the Study of Osteoporotic Fractures who completed wrist actigraphy and the Modified Mini-Mental State Examination (3MS), California Verbal Learning Test-II-Short Form, digit span, verbal fluency tests, and the Trailmaking Test, Part B (Trails B). Total sleep time (TST) and wake after sleep onset (WASO) tertiles were our primary predictors. There were few significant associations in adjusted analyses. Compared to women with intermediate TST (mean = 430.1 minutes), those with the longest (508.7 minutes) had significantly poorer performance on the 3MS and phonemic and semantic fluency. Compared to women with the least WASO (31.5 minutes), those in the middle tertile (61.5 minutes) had significantly poorer delayed recall and those in the middle tertile and highest tertile (126.2 minutes) had poorer total recall and semantic fluency. We observed significant adjusted associations of TST with impaired 3MS performance and of WASO with impaired delayed recall, semantic fluency, and digit span. After excluding participants with adjudicated dementia diagnoses or indeterminate cognitive status, some adjusted associations remained but decreased in magnitude, others became nonsignificant, and a new association emerged. In community-dwelling older women, longer objectively measured sleep duration and greater sleep fragmentation are associated with poorer performance and impairment in only a subset of cognitive domains. Some of these associations may be driven by women with dementia in whom disturbed sleep and cognitive performance share an underlying neuropathological basis. Published by Oxford University Press on behalf of Sleep Research Society (SRS) 2017. This work is written by (a) US Government employee(s) and is in the public domain in the US.

Alternative diagnostic criteria for idiopathic hypersomnia: A 32-hour protocol.

PubMed

Evangelista, Elisa; Lopez, Régis; Barateau, Lucie; Chenini, Sofiene; Bosco, Adriana; Jaussent, Isabelle; Dauvilliers, Yves

2018-02-01

To assess the diagnostic value of extended sleep duration on a controlled 32-hour bed rest protocol in idiopathic hypersomnia (IH). One hundred sixteen patients with high suspicion of IH (37 clear-cut IH according to multiple sleep latency test criteria and 79 probable IH), 32 with hypersomnolence associated with a comorbid disorder (non-IH), and 21 controls underwent polysomnography, modified sleep latency tests, and a 32-hour bed rest protocol. Receiver operating characteristic curves were used to find optimal total sleep time (TST) cutoff values on various periods that discriminate patients from controls. TST was longer in patients with clear-cut IH than other groups (probable IH, non-IH, and controls) and in patients with probable IH than non-IH and controls. The TST cutoff best discriminating clear-cut IH and controls was 19 hours for the 32-hour recording (sensitivity = 91.9%, specificity = 85.7%) and 12 hours (100%, 85.7%) for the first 24 hours. The 19-hour cutoff displayed a specificity and sensitivity of 91.9% and 81.2% between IH and non-IH patients. Patients with IH above the 19-hour cutoff were overweight, had more sleep inertia, and had higher TST on all periods compared to patients below 19 hours, whereas no differences were found for the 12-hour cutoff. An inverse correlation was found between the mean sleep latency and TST during 32-hour recording in IH patients. In standardized and controlled stringent conditions, the optimal cutoff best discriminating patients from controls was 19 hours over 32 hours, allowing a clear-cut phenotypical characterization of major interest for research purposes. Sleepier patients on the multiple sleep latency test were also the more severe in terms of extended sleep. Ann Neurol 2018;83:235-247. © 2018 American Neurological Association.

Work stressors and impaired sleep: rumination as a mediator.

PubMed

Berset, Martial; Elfering, Achim; Lüthy, Stefan; Lüthi, Simon; Semmer, Norbert K

2011-04-01

An association between stress at work and impaired sleep is theoretically plausible and supported by empirical evidence. The current study's main aim was to investigate how the influence of stressors is carried over into the evening and the night. We assume that this relationship is mediated by perseverative cognitions. We tested this assumption in two cross-sectional samples with structural equation modeling, using bootstrapped standard errors to test for significance. Effort–reward imbalance and time pressure were used as stressors, and rumination as a measure for perseverative cognitions. Results show that the stressors are related to perseverative cognitions, and these are related to impaired sleep in both samples. Indirect effects are significant in both samples. With rumination controlled, direct effects of stressors on sleep are only significant in one out of four cases. Thus, there is full mediation in three out of four cases, and partial mediation in the fourth one. Our results underscore the notion that perseverative cognitions are crucial for transferring negative effects of work stressors into private life, including sleep, thus hindering individuals to successfully recover.

Access to Electric Light Is Associated with Shorter Sleep Duration in a Traditionally Hunter-Gatherer Community.

PubMed

de la Iglesia, Horacio O; Fernández-Duque, Eduardo; Golombek, Diego A; Lanza, Norberto; Duffy, Jeanne F; Czeisler, Charles A; Valeggia, Claudia R

2015-08-01

Access to electric light might have shifted the ancestral timing and duration of human sleep. To test this hypothesis, we studied two communities of the historically hunter-gatherer indigenous Toba/Qom in the Argentinean Chaco. These communities share the same ethnic and sociocultural background, but one has free access to electricity while the other relies exclusively on natural light. We fitted participants in each community with wrist activity data loggers to assess their sleep-wake cycles during one week in the summer and one week in the winter. During the summer, participants with access to electricity had a tendency to a shorter daily sleep bout (43 ± 21 min) than those living under natural light conditions. This difference was due to a later daily bedtime and sleep onset in the community with electricity, but a similar sleep offset and rise time in both communities. In the winter, participants without access to electricity slept longer (56 ± 17 min) than those with access to electricity, and this was also related to earlier bedtimes and sleep onsets than participants in the community with electricity. In both communities, daily sleep duration was longer during the winter than during the summer. Our field study supports the notion that access to inexpensive sources of artificial light and the ability to create artificially lit environments must have been key factors in reducing sleep in industrialized human societies. © 2015 The Author(s).

Access to Electric Light Is Associated with Shorter Sleep Duration in a Traditionally Hunter-Gatherer Community

PubMed Central

de la Iglesia, Horacio O.; Fernández-Duque, Eduardo; Golombek, Diego A.; Lanza, Norberto; Duffy, Jeanne F.; Czeisler, Charles A.; Valeggia, Claudia R.

2017-01-01

Access to electric light might have shifted the ancestral timing and duration of human sleep. To test this hypothesis, we studied two communities of the historically hunter-gatherer indigenous Toba/Qom in the Argentinean Chaco. These communities share the same ethnic and sociocultural background, but one has free access to electricity while the other relies exclusively on natural light. We fitted participants in each community with wrist activity data loggers to assess their sleep-wake cycles during one week in the summer and one week in the winter. During the summer, participants with access to electricity had a tendency to a shorter daily sleep bout (43 ± 21 min) than those living under natural light conditions. This difference was due to a later daily bedtime and sleep onset in the community with electricity, but a similar sleep offset and rise time in both communities. In the winter, participants without access to electricity slept longer (56 ± 17 min) than those with access to electricity, and this was also related to earlier bedtimes and sleep onsets than participants in the community with electricity. In both communities, daily sleep duration was longer during the winter than during the summer. Our field study supports the notion that access to inexpensive sources of artificial light and the ability to create artificially lit environments must have been key factors in reducing sleep in industrialized human societies. PMID:26092820

Automated selective disruption of slow wave sleep.

PubMed

Ooms, Sharon J; Zempel, John M; Holtzman, David M; Ju, Yo-El S

2017-04-01

Slow wave sleep (SWS) plays an important role in neurophysiologic restoration. Experimentally testing the effect of SWS disruption previously required highly time-intensive and subjective methods. Our goal was to develop an automated and objective protocol to reduce SWS without affecting sleep architecture. We developed a custom Matlab™ protocol to calculate electroencephalogram spectral power every 10s live during a polysomnogram, exclude artifact, and, if measurements met criteria for SWS, deliver increasingly louder tones through earphones. Middle-aged healthy volunteers (n=10) each underwent 2 polysomnograms, one with the SWS disruption protocol and one with sham condition. The SWS disruption protocol reduced SWS compared to sham condition, as measured by spectral power in the delta (0.5-4Hz) band, particularly in the 0.5-2Hz range (mean 20% decrease). A compensatory increase in the proportion of total spectral power in the theta (4-8Hz) and alpha (8-12Hz) bands was seen, but otherwise normal sleep features were preserved. N3 sleep decreased from 20±34 to 3±6min, otherwise there were no significant changes in total sleep time, sleep efficiency, or other macrostructural sleep characteristics. This novel SWS disruption protocol produces specific reductions in delta band power similar to existing methods, but has the advantage of being automated, such that SWS disruption can be performed easily in a highly standardized and operator-independent manner. This automated SWS disruption protocol effectively reduces SWS without impacting overall sleep architecture. Copyright © 2017 Elsevier B.V. All rights reserved.

Technology-Assisted Behavioral Intervention to Extend Sleep Duration: Development and Design of the Sleep Bunny Mobile App.

PubMed

Baron, Kelly Glazer; Duffecy, Jennifer; Reid, Kathryn; Begale, Mark; Caccamo, Lauren

2018-01-10

Despite the high prevalence of short sleep duration (29.2% of adults sleep <6 hours on weekdays), there are no existing theory-based behavioral interventions to extend sleep duration. The popularity of wearable sleep trackers provides an opportunity to engage users in interventions. The objective of this study was to outline the theoretical foundation and iterative process of designing the "Sleep Bunny," a technology-assisted sleep extension intervention including a mobile phone app, wearable sleep tracker, and brief telephone coaching. We conducted a two-step process in the development of this intervention, which was as follows: (1) user testing of the app and (2) a field trial that was completed by 2 participants with short sleep duration and a cardiovascular disease risk factor linked to short sleep duration (body mass index [BMI] >25). All participants had habitual sleep duration <6.5 hours verified by 7 days of actigraphy. A total of 6 individuals completed initial user testing in the development phase, and 2 participants completed field testing. Participants in the user testing and field testing responded to open-ended surveys about the design and utility of the app. Participants in the field testing completed the Epworth Sleepiness Scale and also wore an actigraph for a 1-week baseline period and during the 4-week intervention period. The feedback suggests that users enjoyed the wearable sleep tracker and found the app visually pleasing, but they suggested improvements to the notification and reminder features of the app. The 2 participants who completed the field test demonstrated significant improvements in sleep duration and daytime sleepiness. Further testing is needed to determine effects of this intervention in populations at risk for the mental and physical consequences of sleep loss. ©Kelly Glazer Baron, Jennifer Duffecy, Kathryn Reid, Mark Begale, Lauren Caccamo. Originally published in JMIR Mental Health (http://mental.jmir.org), 10.01.2018.

Napping facilitates word learning in early lexical development.

PubMed

Horváth, Klára; Myers, Kyle; Foster, Russell; Plunkett, Kim

2015-10-01

Little is known about the role that night-time sleep and daytime naps play in early cognitive development. Our aim was to investigate how napping affects word learning in 16-month-olds. Thirty-four typically developing infants were assigned randomly to nap and wake groups. After teaching two novel object-word pairs to infants, we tested their initial performance with an intermodal preferential looking task in which infants are expected to increase their target looking time compared to a distracter after hearing its auditory label. A second test session followed after approximately a 2-h delay. The delay contained sleep for the nap group or no sleep for the wake group. Looking behaviour was measured with an automatic eye-tracker. Vocabulary size was assessed using the Oxford Communicative Development Inventory. A significant interaction between group and session was found in preferential looking towards the target picture. The performance of the nap group increased after the nap, whereas that of the wake group did not change. The gain in performance correlated positively with the expressive vocabulary size in the nap group. These results indicate that daytime napping helps consolidate word learning in infancy. © 2015 European Sleep Research Society.

Never enough sleep: a brief history of sleep recommendations for children.

PubMed

Matricciani, Lisa Anne; Olds, Tim S; Blunden, Sarah; Rigney, Gabrielle; Williams, Marie T

2012-03-01

There is a common belief that children are not getting enough sleep and that children's total sleep time has been declining. Over the century, many authors have proposed sleep recommendations. The aim of this study was to describe historical trends in recommended and actual sleep durations for children and adolescents, and to explore the rationale of sleep recommendations. A systematic literature review was conducted to identify recommendations for children's sleep requirements and data reporting children's actual total sleep time. For each recommendation identified, children's actual sleep time was determined by identifying studies reporting the sleep duration of children of the same age, gender, and country in the same years. Historical trends in age-adjusted recommended sleep times and trends in children's actual sleep time were calculated. A thematic analysis was conducted to determine the rationale and evidence-base for recommendations. Thirty-two sets of recommendations were located dating from 1897 to 2009. On average, age-specific recommended sleep decreased at the rate of -0.71 minute per year. This rate of decline was almost identical to the decline in the actual sleep duration of children (-0.73 minute per year). Recommended sleep was consistently ∼37 minutes greater than actual sleep, although both declined over time. A lack of empirical evidence for sleep recommendations was universally acknowledged. Inadequate sleep was seen as a consequence of "modern life," associated with technologies of the time. No matter how much sleep children are getting, it has always been assumed that they need more.

Effect of a Short-term Fast on Ketamine–Xylazine Anesthesia in Rats

PubMed Central

Struck, Maggie B; Andrutis, Karl A; Ramirez, Harvey E; Battles, August H

2011-01-01

Although ketamine–xylazine (KX) anesthesia is commonly used in rats, it is often reported to have an inconsistent anesthetic effect, with a prolonged induction time, an inadequate anesthetic plane, or a very short sleep time. Blood flow to the liver is known to shift after a meal in rats, perhaps explaining anesthetic variability among rats with variable prandial status. The current study tested the hypothesis that a short period of fasting (3 h) prior to induction with intraperitoneal KX anesthesia would provide a shorter time to recumbency, a longer total sleep time, and a more consistent loss of toe pinch response than would fed rats. Two groups of male Sprague–Dawley rats were used in blinded, crossover experiments. KX anesthesia was administered at 2 different doses (50 mg/kg–5 mg/kg and 70 mg/kg–7 mg/kg) after ad libitum feeding or a 3-h fast. There were no significant differences between groups in induction time, total sleep time, or loss of toe pinch response. We conclude that fasting rats for 3 h prior to KX intraperitoneal anesthesia does not affect induction time, total sleep time, loss of toe pinch response or reduce KX anesthetic variability in male Sprague–Dawley rats. PMID:21640029

Sleep Does Not Promote Solving Classical Insight Problems and Magic Tricks

PubMed Central

Schönauer, Monika; Brodt, Svenja; Pöhlchen, Dorothee; Breßmer, Anja; Danek, Amory H.; Gais, Steffen

2018-01-01

During creative problem solving, initial solution attempts often fail because of self-imposed constraints that prevent us from thinking out of the box. In order to solve a problem successfully, the problem representation has to be restructured by combining elements of available knowledge in novel and creative ways. It has been suggested that sleep supports the reorganization of memory representations, ultimately aiding problem solving. In this study, we systematically tested the effect of sleep and time on problem solving, using classical insight tasks and magic tricks. Solving these tasks explicitly requires a restructuring of the problem representation and may be accompanied by a subjective feeling of insight. In two sessions, 77 participants had to solve classical insight problems and magic tricks. The two sessions either occurred consecutively or were spaced 3 h apart, with the time in between spent either sleeping or awake. We found that sleep affected neither general solution rates nor the number of solutions accompanied by sudden subjective insight. Our study thus adds to accumulating evidence that sleep does not provide an environment that facilitates the qualitative restructuring of memory representations and enables problem solving. PMID:29535620

Behavioral and genotoxic evaluation of rosmarinic and caffeic acid in acute seizure models induced by pentylenetetrazole and pilocarpine in mice.

PubMed

Coelho, Vanessa Rodrigues; Vieira, Caroline Gonçalves; de Souza, Luana Pereira; da Silva, Lucas Lima; Pflüger, Pricila; Regner, Gabriela Gregory; Papke, Débora Kuck Mausolff; Picada, Jaqueline Nascimento; Pereira, Patrícia

2016-11-01

The goal of this study was to investigate the effects of rosmarinic acid (RA) and caffeic acid (CA) in the acute pentylenetetrazole (PTZ) and pilocarpine (PIL) seizure models. We also evaluated the effect of RA and CA on the diazepam (DZP)-induced sleeping time test and its possible neuroprotective effect against the genotoxic damage induced by PTZ and PIL. Mice were treated intraperitoneally (i.p.) with saline, RA (2 or 4 mg/kg), or CA (4 or 8 mg/kg) alone or associated to low-dose DZP. After, mice received a single dose of PTZ (88 mg/kg) or PIL (250 mg/kg) and were monitored for the percentage of seizures and the latency to first seizure (LFS) >3 s. Vigabatrin and DZP were used as positive controls. In the DZP-induced sleeping time test, mice were treated with RA and CA and 30 min after receiving DZP (25 mg/kg, i.p.). The alkaline comet assay was performed after acute seizure tests to evaluate the antigenotoxic profiles of RA and CA. The doses of RA and CA tested alone did not reduce the occurrence of seizures induced by PTZ or PIL. The association of 4 mg/kg RA + low-dose DZP was shown to increase LFS in the PTZ model, compared to the group that received only the DZP. In the DZP-induced sleeping time test, the latency to sleep was reduced by 4 mg/kg RA and 8 mg/kg CA. The PTZ-induced genotoxic damage was not prevented by RA or CA, but the PIL-induced genotoxic damage was decreased by pretreatment with 4 mg/kg RA (in cortex) and 4 mg/kg CA (in hippocampus). In conclusion, RA and CA presented neuroprotective effect against PIL-induced genotoxic damage and reduced the latency to DZP-induced sleep. Of the rosmarinic acid, 4 mg/kg enhanced the DZP effect in the increase of latency to clonic PTZ-induced seizures.

Sleep/Wake Physiology and Quantitative Electroencephalogram Analysis of the Neuroligin-3 Knockout Rat Model of Autism Spectrum Disorder.

PubMed

Thomas, Alexia M; Schwartz, Michael D; Saxe, Michael D; Kilduff, Thomas S

2017-10-01

Neuroligin-3 (NLGN3) is one of the many genes associated with autism spectrum disorder (ASD). Sleep dysfunction is highly prevalent in ASD, but has not been rigorously examined in ASD models. Here, we evaluated sleep/wake physiology and behavioral phenotypes of rats with genetic ablation of Nlgn3. Male Nlgn3 knockout (KO) and wild-type (WT) rats were assessed using a test battery for ASD-related behaviors and also implanted with telemeters to record the electroencephalogram (EEG), electromyogram, body temperature, and locomotor activity. 24-h EEG recordings were analyzed for sleep/wake states and spectral composition. Nlgn3 KO rats were hyperactive, exhibited excessive chewing behavior, and had impaired prepulse inhibition to an auditory startle stimulus. KO rats also spent less time in non-rapid eye movement (NREM) sleep, more time in rapid eye movement (REM) sleep, exhibited elevated theta power (4-9 Hz) during wakefulness and REM, and elevated delta power (0.5-4 Hz) during NREM. Beta (12-30 Hz) power and gamma (30-50 Hz) power were suppressed across all vigilance states. The sleep disruptions in Nlgn3 KO rats are consistent with observations of sleep disturbances in ASD patients. The EEG provides objective measures of brain function to complement rodent behavioral analyses and therefore may be a useful tool to study ASD. © Sleep Research Society 2017. Published by Oxford University Press on behalf of the Sleep Research Society. All rights reserved. For permissions, please e-mail journals.permissions@oup.com.

Technologically sensed social exposure related to slow-wave sleep in healthy adults.

PubMed

Butt, Maryam; Ouarda, Taha B M J; Quan, Stuart F; Pentland, Alex Sandy; Khayal, Inas

2015-03-01

The aim of this study is to understand the relationship between automatically captured social exposure and detailed sleep parameters of healthy young adults. This study was conducted in a real-world setting in a graduate-student housing community at a US university. Social exposure was measured using Bluetooth proximity sensing technology in mobile devices. Sleep was monitored in a naturalistic setting using a headband sleep monitoring device over a period of 2 weeks. The analysis included a total of 11 subjects (6 males and 5 females) aged 24-35 (149 subject nights). Slow-wave sleep showed a significant positive correlation (Spearman's rho = 0.51, p < 0.0001) with social exposure, whereas light non-REM (N1 + N2) sleep and wake time were found to be negatively correlated (rho = -0.25, p < 0.01; rho = -0.21, p < 0.01, respectively). The correlation of median slow-wave sleep with median social exposure per subject showed a strong positive significance (rho = 0.88, p < 0.001). On average, within subjects, following day's social exposure was higher when (slow-wave NREM + REM) percentage was high (Wilcoxon sign-ranked test, p < 0.05). Subjects with higher social exposure spent more time in slow-wave sleep. Following day's social exposure was found to be positively affected by previous night's (slow-wave NREM + REM) percentage. This suggests that sleep affects following day's social exposure and not vice versa. Capturing an individual's dynamic social behavior and sleep from their natural environment can provide novel insights into these relationships.

Efficacy of Cognitive Behavioral Therapy for Insomnia in Adolescents: A Randomized Controlled Trial with Internet Therapy, Group Therapy and A Waiting List Condition.

PubMed

de Bruin, Eduard J; Bögels, Susan M; Oort, Frans J; Meijer, Anne Marie

2015-12-01

To investigate the efficacy of cognitive behavioral therapy for insomnia (CBTI) in adolescents. A randomized controlled trial of CBTI in group therapy (GT), guided internet therapy (IT), and a waiting list (WL), with assessments at baseline, directly after treatment (post-test), and at 2 months follow-up. Diagnostic interviews were held at the laboratory of the Research Institute of Child Development and Education at the University of Amsterdam. Treatment for GT occurred at the mental health care center UvAMinds in Amsterdam, the Netherlands. One hundred sixteen adolescents (mean age = 15.6 y, SD = 1.6 y, 25% males) meeting DSM-IV criteria for insomnia, were randomized to IT, GT, or WL. CBTI of 6 weekly sessions, consisted of psychoeducation, sleep hygiene, restriction of time in bed, stimulus control, cognitive therapy, and relaxation techniques. GT was conducted in groups of 6 to 8 adolescents, guided by 2 trained sleep therapists. IT was applied through an online guided self-help website with programmed instructions and written feedback from a trained sleep therapist. Sleep was measured with actigraphy and sleep logs for 7 consecutive days. Symptoms of insomnia and chronic sleep reduction were measured with questionnaires. Results showed that adolescents in both IT and GT, compared to WL, improved significantly on sleep efficiency, sleep onset latency, wake after sleep onset, and total sleep time at post-test, and improvements were maintained at follow-up. Most of these improvements were found in both objective and subjective measures. Furthermore, insomnia complaints and symptoms of chronic sleep reduction also decreased significantly in both treatment conditions compared to WL. Effect sizes for improvements ranged from medium to large. A greater proportion of participants from the treatment conditions showed high end-state functioning and clinically significant improvement after treatment and at follow-up compared to WL. This study is the first randomized controlled trial that provides evidence that cognitive behavioral therapy for insomnia is effective for the treatment of adolescents with insomnia, with medium to large effect sizes. There were small differences between internet and group therapy, but both treatments reached comparable endpoints. This study was part of the clinical trial: Effectiveness of cognitive behavioral therapy for sleeplessness in adolescents; URL: http://www.isrctn.com/ISRCTN33922163; registration: ISRCTN33922163. © 2015 Associated Professional Sleep Societies, LLC.

Time frequency analysis for automated sleep stage identification in fullterm and preterm neonates.

PubMed

Fraiwan, Luay; Lweesy, Khaldon; Khasawneh, Natheer; Fraiwan, Mohammad; Wenz, Heinrich; Dickhaus, Hartmut

2011-08-01

This work presents a new methodology for automated sleep stage identification in neonates based on the time frequency distribution of single electroencephalogram (EEG) recording and artificial neural networks (ANN). Wigner-Ville distribution (WVD), Hilbert-Hough spectrum (HHS) and continuous wavelet transform (CWT) time frequency distributions were used to represent the EEG signal from which features were extracted using time frequency entropy. The classification of features was done using feed forward back-propagation ANN. The system was trained and tested using data taken from neonates of post-conceptual age of 40 weeks for both preterm (14 recordings) and fullterm (15 recordings). The identification of sleep stages was successfully implemented and the classification based on the WVD outperformed the approaches based on CWT and HHS. The accuracy and kappa coefficient were found to be 0.84 and 0.65 respectively for the fullterm neonates' recordings and 0.74 and 0.50 respectively for preterm neonates' recordings.

Circadian misalignment, reward-related brain function, and adolescent alcohol involvement.

PubMed

Hasler, Brant P; Clark, Duncan B

2013-04-01

Developmental changes in sleep and circadian rhythms that occur during adolescence may contribute to reward-related brain dysfunction, and consequently increase the risk of alcohol use disorders (AUDs). This review (i) describes marked changes in circadian rhythms, reward-related behavior and brain function, and alcohol involvement that occur during adolescence, (ii) offers evidence that these parallel developmental changes are associated, and (iii) posits a conceptual model by which misalignment between sleep-wake timing and endogenous circadian timing may increase the risk of adolescent AUDs by altering reward-related brain function. The timing of sleep shifts later throughout adolescence, in part due to developmental changes in endogenous circadian rhythms, which tend to become more delayed. This tendency for delayed sleep and circadian rhythms is at odds with early school start times during secondary education, leading to misalignment between many adolescents' sleep-wake schedules and their internal circadian timing. Circadian misalignment is associated with increased alcohol use and other risk-taking behaviors, as well as sleep loss and sleep disturbance. Growing evidence indicates that circadian rhythms modulate the reward system, suggesting that circadian misalignment may impact adolescent alcohol involvement by altering reward-related brain function. Neurocognitive function is also subject to sleep and circadian influence, and thus circadian misalignment may also impair inhibitory control and other cognitive processes relevant to alcohol use. Specifically, circadian misalignment may further exacerbate the cortical-subcortical imbalance within the reward circuit, an imbalance thought to explain increased risk-taking and sensation-seeking during adolescence. Adolescent alcohol use is highly contextualized, however, and thus studies testing this model will also need to consider factors that may influence both circadian misalignment and alcohol use. This review highlights growing evidence supporting a path by which circadian misalignment may disrupt reward mechanisms, which may in turn accelerate the transition from alcohol use to AUDs in vulnerable adolescents. Copyright © 2013 by the Research Society on Alcoholism.

Hyperactivity and male-specific sleep deficits in the 16p11.2 deletion mouse model of autism.

PubMed

Angelakos, Christopher C; Watson, Adam J; O'Brien, W Timothy; Krainock, Kyle S; Nickl-Jockschat, Thomas; Abel, Ted

2017-04-01

Sleep disturbances and hyperactivity are prevalent in several neurodevelopmental disorders, including autism spectrum disorders (ASDs) and attention deficit-hyperactivity disorder (ADHD). Evidence from genome-wide association studies indicates that chromosomal copy number variations (CNVs) are associated with increased prevalence of these neurodevelopmental disorders. In particular, CNVs in chromosomal region 16p11.2 profoundly increase the risk for ASD and ADHD, disorders that are more common in males than females. We hypothesized that mice hemizygous for the 16p11.2 deletion (16p11.2 del/+) would exhibit sex-specific sleep and activity alterations. To test this hypothesis, we recorded activity patterns using infrared beam breaks in the home-cage of adult male and female 16p11.2 del/+ and wildtype (WT) littermates. In comparison to controls, we found that both male and female 16p11.2 del/+ mice exhibited robust home-cage hyperactivity. In additional experiments, sleep was assessed by polysomnography over a 24-hr period. 16p11.2 del/+ male, but not female mice, exhibited significantly more time awake and significantly less time in non-rapid-eye-movement (NREM) sleep during the 24-hr period than wildtype littermates. Analysis of bouts of sleep and wakefulness revealed that 16p11.2 del/+ males, but not females, spent a significantly greater proportion of wake time in long bouts of consolidated wakefulness (greater than 42 min in duration) compared to controls. These changes in hyperactivity, wake time, and wake time distribution in the males resemble sleep disturbances observed in human ASD and ADHD patients, suggesting that the 16p11.2 del/+ mouse model may be a useful genetic model for studying sleep and activity problems in human neurodevelopmental disorders. Autism Res 2016. © 2016 International Society for Autism Research, Wiley Periodicals, Inc. Autism Res 2017, 10: 572-584. © 2016 International Society for Autism Research, Wiley Periodicals, Inc. © 2016 International Society for Autism Research, Wiley Periodicals, Inc.

The Circadian Clock Gene Csnk1e Regulates Rapid Eye Movement Sleep Amount, and Nonrapid Eye Movement Sleep Architecture in Mice

PubMed Central

Zhou, Lili; Bryant, Camron D.; Loudon, Andrew; Palmer, Abraham A.; Vitaterna, Martha Hotz; Turek, Fred W.

2014-01-01

Study Objectives: Efforts to identify the genetic basis of mammalian sleep have included quantitative trait locus (QTL) mapping and gene targeting of known core circadian clock genes. We combined three different genetic approaches to identify and test a positional candidate sleep gene — the circadian gene casein kinase 1 epsilon (Csnk1e), which is located in a QTL we identified for rapid eye movement (REM) sleep on chromosome 15. Measurements and Results: Using electroencephalographic (EEG) and electromyographic (EMG) recordings, baseline sleep was examined in a 12-h light:12-h dark (LD 12:12) cycle in mice of seven genotypes, including Csnk1etau/tau and Csnk1e-/- mutant mice, Csnk1eB6.D2 and Csnk1eD2.B6 congenic mice, and their respective wild-type littermate control mice. Additionally, Csnk1etau/tau and wild-type mice were examined in constant darkness (DD). Csnk1etau/tau mutant mice and both Csnk1eB6.D2 and Csnk1eD2.B6 congenic mice showed significantly higher proportion of sleep time spent in REM sleep during the dark period than wild-type controls — the original phenotype for which the QTL on chromosome 15 was identified. This phenotype persisted in Csnk1etau/tau mice while under free-running DD conditions. Other sleep phenotypes observed in Csnk1etau/tau mice and congenics included a decreased number of bouts of nonrapid eye movement (NREM) sleep and an increased average NREM sleep bout duration. Conclusions: These results demonstrate a role for Csnk1e in regulating not only the timing of sleep, but also the REM sleep amount and NREM sleep architecture, and support Csnk1e as a causal gene in the sleep QTL on chromosome 15. Citation: Zhou L; Bryant CD; Loudon A; Palmer AA; Vitaterna MH; Turek FW. The circadian clock gene Csnk1e regulates rapid eye movement sleep amount, and nonrapid eye movement sleep architecture in mice. SLEEP 2014;37(4):785-793. PMID:24744456

Effects of caffeine, sleep loss, and stress on cognitive performance and mood during U.S. Navy SEAL training. Sea-Air-Land.

PubMed

Lieberman, Harris R; Tharion, William J; Shukitt-Hale, Barbara; Speckman, Karen L; Tulley, Richard

2002-11-01

When humans are acutely exposed to multiple stressors, cognitive performance is substantially degraded. Few practical strategies are available to sustain performance under such conditions. This study examined whether moderate doses of caffeine would reduce adverse effects of sleep deprivation and exposure to severe environmental and operational stress on cognitive performance. Volunteers were 68 U.S. Navy Sea-Air-Land (SEAL) trainees, randomly assigned to receive either 100, 200, or 300 mg caffeine or placebo in capsule form after 72 h of sleep deprivation and continuous exposure to other stressors. Cognitive tests administered included scanning visual vigilance, four-choice visual reaction time, a matching-to-sample working memory task and a repeated acquisition test of motor learning and memory. Mood state, marksmanship, and saliva caffeine were also assessed. Testing was conducted 1 and 8 h after treatment. Sleep deprivation and environmental stress adversely affected performance and mood. Caffeine, in a dose-dependent manner, mitigated many adverse effects of exposure to multiple stressors. Caffeine (200 and 300 mg) significantly improved visual vigilance, choice reaction time, repeated acquisition, self-reported fatigue and sleepiness with the greatest effects on tests of vigilance, reaction time, and alertness. Marksmanship, a task that requires fine motor coordination and steadiness, was not affected by caffeine. The greatest effects of caffeine were present 1 h post-administration, but significant effects persisted for 8 h. Even in the most adverse circumstances, moderate doses of caffeine can improve cognitive function, including vigilance, learning, memory, and mood state. When cognitive performance is critical and must be maintained during exposure to severe stress, administration of caffeine may provide a significant advantage. A dose of 200 mg appears to be optimal under such conditions.

The Effects of Sleep Continuity Disruption on Positive Mood and Sleep Architecture in Healthy Adults

PubMed Central

Finan, Patrick H.; Quartana, Phillip J.; Smith, Michael T.

2015-01-01

Objective: The purpose of this study was to test an experimental model of the effects of sleep continuity disturbance on sleep architecture and positive mood in order to better understand the mechanisms linking insomnia and depression. Design: Participants were randomized to receive 3 consecutive nights of sleep continuity disruption via forced nocturnal awakenings (FA, n = 21), or one of two control conditions: restricted sleep opportunity (RSO, n = 17) or uninterrupted sleep (US, n = 24). Setting: The study was set in an inpatient clinical research suite. Participants: Healthy, good-sleeping men and women were included. Measurement and Results: Polysomnography was used to measure sleep architecture, and mood was assessed via self-report each day. Compared to restricted sleep opportunity controls, forced awakenings subjects had significantly less slow wave sleep (P < 0.05) after the first night of sleep deprivation, and significantly lower positive mood (P < 0.05) after the second night of sleep deprivation. The differential change in slow wave sleep statistically mediated the observed group differences in positive mood (P = 0.002). Conclusions: To our knowledge, this is the first human experimental study to demonstrate that, despite comparable reductions in total sleep time, partial sleep loss from sleep continuity disruption is more detrimental to positive mood than partial sleep loss from delaying bedtime, even when controlling for concomitant increases in negative mood. With these findings, we provide temporal evidence in support of a putative biologic mechanism (slow wave sleep deficit) that could help explain the strong comorbidity between insomnia and depression. Citation: Finan PH, Quartana PJ, Smith MT. The effects of sleep continuity disruption on positive mood and sleep architecture in healthy adults. SLEEP 2015;38(11):1735–1742. PMID:26085289

Electrocardiogram-Based Sleep Spectrogram Measures of Sleep Stability and Glucose Disposal in Sleep Disordered Breathing

PubMed Central

Pogach, Melanie S.; Punjabi, Naresh M.; Thomas, Neil; Thomas, Robert J.

2012-01-01

Study Objectives: Sleep disordered breathing (SDB) is independently associated with insulin resistance, glucose intolerance, and type 2 diabetes mellitus. Experimental sleep fragmentation has been shown to impair insulin sensitivity. Conventional electroencephalogram (EEG)-based sleep-quality measures have been inconsistently associated with indices of glucose metabolism. This analysis explored associations between glucose metabolism and an EEG-independent measure of sleep quality, the sleep spectrogram, which maps coupled oscillations of heart-rate variability and electrocardiogram (ECG)-derived respiration. The method allows improved characterization of the quality of stage 2 non-rapid eye movement (NREM) sleep. Design: Cross-sectional study. Setting: N/A. Participants: Nondiabetic subjects with and without SDB (n = 118) underwent the frequently sampled intravenous glucose tolerance test (FSIVGTT) and a full-montage polysomnogram. The sleep spectrogram was generated from ECG collected during polysomnography. Interventions: N/A. Measurements and Results: Standard polysomnographic stages (stages 1, 2, 3+4, and rapid eye movement [REM]) were not associated with the disposition index (DI) derived from the FSIVGTT. In contrast, spectrographic high-frequency coupling (a marker of stable or “effective” sleep) duration was associated with increased, and very-low-frequency coupling (a marker of wake/REM/transitions) associated with reduced DI. This relationship was noted after adjusting for age, sex, body mass index, slow wave sleep, total sleep time, stage 1, the arousal index, and the apnea-hypopnea index. Conclusions: ECG-derived sleep-spectrogram measures of sleep quality are associated with alterations in glucose-insulin homeostasis. This alternate mode of estimating sleep quality could improve our understanding of sleep and sleep-breathing effects on glucose metabolism. Citation: Pogach MS; Punjabi NM; Thomas N; Thomas RJ. Electrocardiogram-based sleep spectrogram measures of sleep stability and glucose disposal in sleep disordered breathing. SLEEP 2012;35(1):139-148. PMID:22215928

Sleep patterns and sleepiness among young students: A longitudinal study before and after admission as trainees and apprentices.

PubMed

Fischer, Frida Marina; Wey, Daniela; Valente, Daniel; Luz, Andréa Aparecida da; Pinheiro, Fernando; Fonseca, Barbara Cristina; Silva-Costa, Aline; Moreno, Claudia Roberta; Menna-Barreto, Luiz; Teixeira, Liliane Reis

2015-05-01

In developing countries, youngsters start to work during the high school years. Several studies have shown the difficulties associated with double shift, i.e. to work and study concomitantly, and its negative health consequences. Work and study time, as social synchronizers, have significant effects on the sleep-wake cycle (SWC). The purpose of this study was to evaluate sleep patterns and sleepiness in young students before and after entering the workforce as apprentices or trainees. Participants were 40 adolescents (26 males), 15-18 years old (mean = 15.8 years old) engaged in a first-job program at a non-governmental organization (NGO) while attending evening high school in the outskirts of the city of São Paulo, Brazil. The participants wore actigraphs (Ambulatory Monitoring, Inc.) and registered subjective sleepiness on KSS (Karolinska Sleepiness Scale) along 7 consecutive days, before and after admission to the job. Descriptive analyses were performed, and the variables were tested by means of the t-test and repeated measures ANOVA taking factors day of the week and time of the day into consideration. The participants' sleep duration on weekdays exhibited significant difference before and after starting work (F = 4.55; p = 0.04); the mean sleep duration was 492 min (SD = 44 min) before admission to the job to decrease to 405 min (SD = 58 min) after starting work. The mid-sleep time exhibited significant difference on weekdays before and after starting work (04:57 h; SD = 45 min versus 03:30 h; SD = 54 min; F = 4.91; p = 0.03). Finally, also sleepiness on weekdays (F = 6.41; p = 0.04) and at the waking time (F = 10.75; p < 0.01) exhibited significant difference before and after admission to the job. This article emphasizes the fact that social synchronizers like working during the day and studying in the evening changed the participants' SWC and were associated with sleep restriction. Brazilian governmental incentives notwithstanding, simultaneous performance of several activities by young workers should be considered as an occupational health hazard. Employment policies targeting young workers should take the dual shift - study and work - and its effects on the sleep-wake cycle into account.

Validation of the German version of the Ford Insomnia Response to Stress Test.

PubMed

Dieck, Arne; Helbig, Susanne; Drake, Christopher L; Backhaus, Jutta

2018-06-01

The purpose of this study was to assess the psychometric properties of a German version of the Ford Insomnia Response to Stress Test with groups with and without sleep problems. Three studies were analysed. Data set 1 was based on an initial screening for a sleep training program (n = 393), data set 2 was based on a study to test the test-retest reliability of the Ford Insomnia Response to Stress Test (n = 284) and data set 3 was based on a study to examine the influence of competitive sport on sleep (n = 37). Data sets 1 and 2 were used to test internal consistency, factor structure, convergent validity, discriminant validity and test-retest reliability of the Ford Insomnia Response to Stress Test. Content validity was tested using data set 3. Cronbach's alpha of the Ford Insomnia Response to Stress Test was good (α = 0.80) and test-retest reliability was satisfactory (r = 0.72). Overall, the one-factor model showed the best fit. Furthermore, significant positive correlations between the Ford Insomnia Response to Stress Test and impaired sleep quality, depression and stress reactivity were in line with the expectations regarding the convergent validity. Subjects with sleep problems had significantly higher scores in the Ford Insomnia Response to Stress Test than subjects without sleep problems (P < 0.01). Competitive athletes with higher scores in the Ford Insomnia Response to Stress Test had significantly lower sleep quality (P = 0.01), demonstrating that vulnerability for stress-induced sleep disturbances accompanies poorer sleep quality in stressful episodes. The findings show that the German version of the Ford Insomnia Response to Stress Test is a reliable and valid questionnaire to assess the vulnerability to stress-induced sleep disturbances. © 2017 European Sleep Research Society.

Adolescents' technology and face-to-face time use predict objective sleep outcomes.

PubMed

Tavernier, Royette; Heissel, Jennifer A; Sladek, Michael R; Grant, Kathryn E; Adam, Emma K

2017-08-01

The present study examined both within- and between-person associations between adolescents' time use (technology-based activities and face-to-face interactions with friends and family) and sleep behaviors. We also assessed whether age moderated associations between adolescents' time use with friends and family and sleep. Adolescents wore an actigraph monitor and completed brief evening surveys daily for 3 consecutive days. Adolescents (N=71; mean age=14.50 years old, SD=1.84; 43.7% female) were recruited from 3 public high schools in the Midwest. We assessed 8 technology-based activities (eg, texting, working on a computer), as well as time spent engaged in face-to-face interactions with friends and family, via questions on adolescents' evening surveys. Actigraph monitors assessed 3 sleep behaviors: sleep latency, sleep hours, and sleep efficiency. Hierarchical linear models indicated that texting and working on the computer were associated with shorter sleep, whereas time spent talking on the phone predicted longer sleep. Time spent with friends predicted shorter sleep latencies, while family time predicted longer sleep latencies. Age moderated the association between time spent with friends and sleep efficiency, as well as between family time and sleep efficiency. Specifically, longer time spent interacting with friends was associated with higher sleep efficiency but only among younger adolescents. Furthermore, longer family time was associated with higher sleep efficiency but only for older adolescents. Findings are discussed in terms of the importance of regulating adolescents' technology use and improving opportunities for face-to-face interactions with friends, particularly for younger adolescents. Copyright © 2017 National Sleep Foundation. Published by Elsevier Inc. All rights reserved.

Mid-Treatment Sleep Duration Predicts Clinically Significant Knee Osteoarthritis Pain reduction at 6 months: Effects From a Behavioral Sleep Medicine Clinical Trial.

PubMed

Salwen, Jessica K; Smith, Michael T; Finan, Patrick H

2017-02-01

To determine the relative influence of sleep continuity (sleep efficiency, sleep onset latency, total sleep time [TST], and wake after sleep onset) on clinical pain outcomes within a trial of cognitive behavioral therapy for insomnia (CBT-I) for patients with comorbid knee osteoarthritis and insomnia. Secondary analyses were performed on data from 74 patients with comorbid insomnia and knee osteoarthritis who completed a randomized clinical trial of 8-session multicomponent CBT-I versus an active behavioral desensitization control condition (BD), including a 6-month follow-up assessment. Data used herein include daily diaries of sleep parameters, actigraphy data, and self-report questionnaires administered at specific time points. Patients who reported at least 30% improvement in self-reported pain from baseline to 6-month follow-up were considered responders (N = 31). Pain responders and nonresponders did not differ significantly at baseline across any sleep continuity measures. At mid-treatment, only TST predicted pain response via t tests and logistic regression, whereas other measures of sleep continuity were nonsignificant. Recursive partitioning analyses identified a minimum cut-point of 382 min of TST achieved at mid-treatment in order to best predict pain improvements 6-month posttreatment. Actigraphy results followed the same pattern as daily diary-based results. Clinically significant pain reductions in response to both CBT-I and BD were optimally predicted by achieving approximately 6.5 hr sleep duration by mid-treatment. Thus, tailoring interventions to increase TST early in treatment may be an effective strategy to promote long-term pain reductions. More comprehensive research on components of behavioral sleep medicine treatments that contribute to pain response is warranted. © Sleep Research Society 2016. Published by Oxford University Press on behalf of the Sleep Research Society. All rights reserved. For permissions, please e-mail journals.permissions@oup.com.

Knockdown of orexin type 2 receptor in the lateral pontomesencephalic tegmentum of rats increases REM sleep

PubMed Central

Chen, Lichao; McKenna, James T.; Bolortuya, Yunren; Brown, Ritchie E.

2012-01-01

Dysfunction of the orexin/hypocretin neurotransmitter system causes the sleep disorder narcolepsy, characterized by intrusion of rapid-eye-movement (REM) sleep-like events into normal wakefulness. The sites where orexins act to suppress REM sleep are incompletely understood. Previous studies suggested that the lateral pontomesencephalic tegmentum (lPMT) contains an important REM sleep inhibitory area, and proposed that orexins inhibit REM sleep via orexin type 2 receptors (OxR2) in this region. However, this hypothesis has heretofore not been tested. We thus performed bilateral injection of small interfering RNAs (siRNAs) targeting Ox2R into the lPMT on two consecutive days. This led to a ~30 % increase of time spent in REM sleep in both the dark and light periods for the first two days after injection, with a return to baseline over the next two post-injection days. This increase was mainly due to more longer (>120 s) REM episodes. Cataplexy-like episodes were not observed. The percentage of time spent in wakefulness and NREM sleep, as well as the power spectral profile of NREM and REM sleep, were unaffected. Control animals injected with scrambled siRNA had no sleep changes post-injection. Quantification of the knockdown revealed that unilateral microinjection of siRNAs targeting OxR2 into the lPMT induced a ~40% reduction of OxR2 mRNA two days following the injections when compared to the contralateral side receiving control (scrambled) siRNA. Orexin type 1 receptor (OxR1) mRNA level was unaffected. Our results indicate that removal of OxR2 neurotransmission in the lPMT enhances REM sleep by increasing the duration of REM episodes. PMID:23282008

Short Daytime Naps Briefly Attenuate Objectively Measured Sleepiness Under Chronic Sleep Restriction.

PubMed

Saletin, Jared M; Hilditch, Cassie J; Dement, William C; Carskadon, Mary A

2017-09-01

Napping is a useful countermeasure to the negative effects of acute sleep loss on alertness. The efficacy of naps to recover from chronic sleep loss is less well understood. Following 2 baseline nights (10 hours' time-in-bed), participants were restricted to 7 nights of 5-hour sleep opportunity. Ten adults participated in the No-Nap condition, and a further 9 were assigned to a Nap condition with a daily 45-minute nap opportunity at 1300 h. Sleepiness was assessed using the multiple sleep latency test and a visual analogue scale at 2-hour intervals. Both objective and subjective indexes of sleepiness were normalized within subject as a difference from those at baseline prior to sleep restriction. Mixed-effects models examined how the daytime nap opportunity altered sleepiness across the day and across the protocol. Short daytime naps attenuated sleepiness due to chronic sleep restriction for up to 6-8 hours after the nap. Benefits of the nap did not extend late into evening. Subjective sleepiness demonstrated a similar short-lived benefit that emerged later in the day when objective sleepiness already returned to pre-nap levels. Neither measure showed a benefit of the nap the following morning after the subsequent restriction night. These data indicate a short daytime nap may attenuate sleepiness in chronic sleep restriction, yet subjective and objective benefits emerge at different time scales. Because neither measure showed a benefit the next day, the current study underscores the need for careful consideration before naps are used as routine countermeasures to chronic sleep loss. © Sleep Research Society 2017. Published by Oxford University Press on behalf of the Sleep Research Society. All rights reserved. For permissions, please e-mail journals.permissions@oup.com.

Dormitory of Physical and Engineering Sciences: Sleeping Beauties May Be Sleeping Innovations

PubMed Central

van Raan, Anthony F. J.

2015-01-01

A ‘Sleeping Beauty in Science’ is a publication that goes unnoticed (‘sleeps’) for a long time and then, almost suddenly, attracts a lot of attention (‘is awakened by a prince’). The aim of this paper is to present a general methodology to investigate (1) important properties of Sleeping Beauties such as the time-dependent distribution, author characteristics, journals and fields, and (2) the cognitive environment of Sleeping Beauties. We are particularly interested to find out to what extent Sleeping Beauties are application-oriented and thus are potential Sleeping Innovations. In this study we focus primarily on physics (including materials science and astrophysics) and present first results for chemistry and for engineering & computer science. We find that more than half of the SBs are application-oriented. To study the cognitive environments of Sleeping Beauties we develop a new approach in which the cognitive environment of the SBs is analyzed, based on the mapping of Sleeping Beauties using their citation links and conceptual relations, particularly co-citation mapping. In this way we investigate the research themes in which the SBs are ‘used’ and possible causes of why the premature work in the SBs becomes topical, i.e., the trigger of the awakening of the SBs. This approach is tested with a blue skies SB and an application-oriented SB. We think that the mapping procedures discussed in this paper are not only important for bibliometric analyses. They also provide researchers with useful, interactive tools to discover both relevant older work as well as new developments, for instance in themes related to Sleeping Beauties that are also Sleeping Innovations. PMID:26469987

Start Later, Sleep Later: School Start Times and Adolescent Sleep in Homeschool Versus Public/Private School Students.

PubMed

Meltzer, Lisa J; Shaheed, Keisha; Ambler, Devon

2016-01-01

Homeschooled students provide a naturalistic comparison group for later/flexible school start times. This study compared sleep patterns and sleep hygiene for homeschooled students and public/private school students (grades 6-12). Public/private school students (n = 245) and homeschooled students (n = 162) completed a survey about sleep patterns and sleep hygiene. Significant school group differences were found for weekday bedtime, wake time, and total sleep time, with homeschooled students waking later and obtaining more sleep. Homeschooled students had later school start times, waking at the same time that public/private school students were starting school. Public/private school students had poorer sleep hygiene practices, reporting more homework and use of technology in the hour before bed. Regardless of school type, technology in the bedroom was associated with shorter sleep duration. Later school start times may be a potential countermeasure for insufficient sleep in adolescents. Future studies should further examine the relationship between school start times and daytime outcomes, including academic performance, mood, and health.

[Analysis on sleep duration of 6-12 years old school children in school-day in 8 provinces, China].

PubMed

Shi, Wenhui; Zhai, Yi; Li, Weirong; Shen, Chong; Shi, Xiaoming

2015-05-01

To analyze the influencing factors for sleep duration of school children aged 6-12 years in school-day in 8 provinces in China. The cross sectional study was conducted among 20,603 children aged 6-12 years and selected through stratified random cluster sampling in 8 provinces (municipality and autonomous region) with different geographic characteristics and economic development level in China from September to November, 2010 to understand their sleep duration in school-day and related habits. t test and χ2 test were used to compare the sleep duration of the children. Multivariate stepwise logistic regression analysis was conducted to identify the influencing factors. The survey indicated that the daily average sleep duration of the children in school days was 9.11 hours. The proportions of the children with serious insufficient sleep, insufficient sleep and sufficient sleep were 32.82% (7,672/20,603), 39.70% (8,179/20,603) and 27.48% (5,662/20,603), the children's sleep duration declined with age, so did proportion of children with serious insufficient sleep. There were no sex, urban or rural area and household income level specific significant differences in sleep duration among the children surveyed, and there were no sex specific differences in the proportion of children with serious insufficient sleep, insufficient sleep and sufficient sleep, however, these proportions were statistically different between urban area and rural area and among the regions with different economic level. The proportions of children with serious insufficient sleep and sufficient sleep was higher in rural area than in urban area (χ2=59.96, χ2=45.47, P<0.05), while the proportion of children with insufficient sleep was lower in rural area than in urban area. In the economy developed region, the proportion of children with insufficient sleep was lowest, the difference was statistical significant. After adjusting for sex, weight, diet and exercise time, multivariate logistic regression analysis showed that the factors benefiting children to have 10 hours sleep every day included having high protein diet, exercise, high household economic status and living in urban area. The problem of school children having insufficient sleep was serious in China, especially in the rural area.

Preference for social contact versus environmental enrichment in male laboratory mice.

PubMed

Van Loo, P L P; Van de Weerd, H A; Van Zutphen, L F M; Baumans, V

2004-04-01

Due to their aggressive nature, male mice are less frequently used than female mice in biomedical research. When aggressive males are being used, individual housing is common practice. The question arises whether this is an acceptable housing for a social species. The present study was designed to gain more insight into the nature of inter-male social contact and into the potential of a form of environmental enrichment (nesting material) to compensate for the lack of social contact. In a series of tests, we analysed whether male mice of different ages preferred to spend time (1) near a familiar cage mate versus an empty cage, or (2) near to a familiar cage mate versus direct contact with nesting material (tissues). Dwelling time in each of the test cages and sleeping sites was recorded, as was the behaviour of the test mice. Results indicated that when other conditions were similar, male mice preferred to sleep in close proximity to their familiar cage mate. Furthermore, the need to engage in active social behaviour increased with age. Tissues were used to a large extent for sleeping and sleep-related behaviour. It is concluded that single housing in order to avoid aggression between male mice is a solution with evident negative consequences for the animals. When individual housing is inevitable due to excessive aggressive behaviour, the presence of nesting material could partly compensate for the deprivation of social contact.

Sleep disturbances in Angelman syndrome: a questionnaire study.

PubMed

Bruni, Oliviero; Ferri, Raffaele; D'Agostino, Gaetana; Miano, Silvia; Roccella, Michele; Elia, Maurizio

2004-06-01

Only few studies are available on sleep disorders in Angelman syndrome (AS), a neurodevelopmental disorder with several behavior disturbances. The aim of this study was to determine the prevalence of sleep disorders in a relatively large group of AS subjects, compared to that of age-matched controls. Forty-nine consecutive parents of patients with AS (26 males and 23 females aged 2.3-26.2 years) were interviewed and filled out a comprehensive sleep questionnaire. Based on their genetic etiology, four groups were defined: deletion of chromosome 15q11-13 (25 subjects); methylation imprinting mutation (six subjects), UBE3A mutations (seven subjects) and paternal uniparental disomy (five subjects). In the remaining cases genetic testings were negative. A significantly high frequency of disorders of initiating and maintaining sleep, prolonged sleep latency, prolonged wakefulness after sleep onset, high number of night awakenings and reduced total sleep time were found in our AS patients, as compared to age-matched controls. We also found other types of sleep disorders, never reported before, such as enuresis, bruxism, sleep terrors, somnambulism, nocturnal hyperkinesia, and snoring. No differences were found between the four genetic aetiology groups. Moreover, we did not find important improvement of sleep disturbances from pre-pubertal to post-pubertal ages. Our data confirm the significant presence of sleep/wake rhythms fragmentation, peculiar of AS, and also demonstrate the presence of several other types of sleep disturbances in this syndrome.

A new face of sleep: The impact of post-learning sleep on recognition memory for face-name associations.

PubMed

Maurer, Leonie; Zitting, Kirsi-Marja; Elliott, Kieran; Czeisler, Charles A; Ronda, Joseph M; Duffy, Jeanne F

2015-12-01

Sleep has been demonstrated to improve consolidation of many types of new memories. However, few prior studies have examined how sleep impacts learning of face-name associations. The recognition of a new face along with the associated name is an important human cognitive skill. Here we investigated whether post-presentation sleep impacts recognition memory of new face-name associations in healthy adults. Fourteen participants were tested twice. Each time, they were presented 20 photos of faces with a corresponding name. Twelve hours later, they were shown each face twice, once with the correct and once with an incorrect name, and asked if each face-name combination was correct and to rate their confidence. In one condition the 12-h interval between presentation and recall included an 8-h nighttime sleep opportunity ("Sleep"), while in the other condition they remained awake ("Wake"). There were more correct and highly confident correct responses when the interval between presentation and recall included a sleep opportunity, although improvement between the "Wake" and "Sleep" conditions was not related to duration of sleep or any sleep stage. These data suggest that a nighttime sleep opportunity improves the ability to correctly recognize face-name associations. Further studies investigating the mechanism of this improvement are important, as this finding has implications for individuals with sleep disturbances and/or memory impairments. Copyright © 2015 Elsevier Inc. All rights reserved.

An investigation on sleep behaviors of the elderly hospitalized in Zahedan

PubMed Central

Sargazi, Maryam; Salehi, Shayesteh; Naji, Seyed Ali

2012-01-01

Background: Sleep is an essential need in every individual's life. A disorder in the natural sleep can cause physical and mental problems. The elderly are usually faced with more sleep problems. Therefore, the present study aimed to define sleep behavior among the elderly hospitalized in Zahedan. Materials and Methods: This is a descriptive analytical study conducted on 300 elderly people aged 60 years and over who were hospitalized in Zahedan. In this research convenience sampling method was used and the research tool was a questionnaire. The data were collected through interviews. Descriptive (frequency distribution) and inferential (X2) statistical tests were employed to analyze the data. Findings: The results showed that 62% of the hospitalized elderly people (total of 300) had sleep disorder. About 44.7%took sleep medication in order to sleep, and only 16.7% did not take sleeping medications. About 44.7% had no special schedule for the time of their sleeping and waking up, and 4.3% were involved in drug abuse and smoking, and had a big dinner before sleeping. There was a significant association between sleep disorder, gender, education, living in urban or rural areas, the cause of hospitalization, and suffering from a chronic disease Conclusions: Sleep disorder and inappropriate sleep related behaviors had a high prevalence among the elderly. With regard to the important role of sleep in the quality of life of the elderly, detection of the reasons of sleep disorder, motivating them to practice an appropriate sleep behavior, and preventing them from having inappropriate sleep related behaviors are crucial issues. PMID:23493461

Ambulatory Surgery Has Minimal Impact on Sleep Parameters: A Prospective Observational Trial.

PubMed

Hudson, Arlene J; Walter, Robert J; Flynn, John; Szpisjak, Dale F; Olsen, Cara; Rodgers, Matthew; Capaldi, Vincent F; McDuffie, Brent; Lettieri, Christopher J

2018-04-15

The presence of obstructive sleep apnea (OSA) in ambulatory surgical patients causes significant perioperative concern; however, few data exist to guide clinicians' management decisions. The objective of this study was to measure changes in perioperative sleep parameters among an ambulatory surgery population. This study is a prospective, observational study of ambulatory patients undergoing orthopedic surgery on an extremity. Study subjects completed three unattended home sleep apnea tests: baseline before surgery, the first night after surgery (N1), and third night after surgery (N3). Anesthesia and surgical teams were blinded to study participation and patients received routine perioperative care. Two hundred three subjects were enrolled and 166 completed the baseline home sleep test. Sixty-six (40.0%) had OSA at baseline, 35 patients received a new diagnosis, and 31 patients had a previous diagnosis of OSA. Of those with a previous diagnosis, 20 (64.5%) were compliant with continuous positive airway pressure therapy. Respiratory event index and SpO 2 nadir did not significantly change postoperatively from baseline. Cumulative percentage of time oxygen saturation < 90% significantly increased N1 as compared to baseline for all patients except for those with moderate to severe OSA. Ambulatory surgery had minimal effect on sleep parameters and there was no increase in adverse events among patients with either treated or untreated OSA. Registry: ClinicalTrials.gov; Title: Evaluation of Sleep Disordered Breathing Following Ambulatory Surgery; Identifier: NCT01851798; URL: https://clinicaltrials.gov/ct2/show/study/NCT01851798. © 2018 American Academy of Sleep Medicine.

Sleep Habits and Sleep Problems in Healthy Preschoolers.

PubMed

Murthy, C L Srinivasa; Bharti, Bhavneet; Malhi, Prahbhjot; Khadwal, Alka

2015-07-01

To describe the sleep patterns and problems in children aged between 12 and 36 mo of age. This cross sectional survey was collected over a span of 1 y in Advanced Pediatric Centre, PGIMER, Chandigarh and crèches of Chandigarh. Children in the age group of 12 to 36 mo were included in study. Children with chronic illness, developmental delay, seizure disorder and lack of consent were excluded. A total of 368 children were enrolled. Main outcome measures were sleep duration over 1 to 3 y of life; sleep behavior at onset, during and waking of sleep and parent reported sleep problems and their predictors. The average duration of sleep was 12.5 h (S.D = 1.9). The mean total sleep duration and mean day time sleep duration decreased, while mean night time sleep increased as the age advanced from 12 to 36 mo. Following were the frequency of sleep habits seen in the index study; bed time routine was seen only in 68(18.5 %), a regular bed time ritual was seen in 281(76.4 %), 329(89.4 %) children frequently required 0-20 min time to fall asleep, 11(3 %) parents used sleep inducing drugs. Night waking (1 to 3 times a night) was seen in 297(80.7 %) and its frequency declined with age. Parent reported sleep problems were seen in 12.8 % (47/368). Lack of co-sleeping and night waking were considered as strongest predictors of parent reported sleep problems. Toddlers' sleep duration, night waking behavior, and day time naps decrease as the age progress while night time sleep duration increases with age. Lack of co-sleeping and night waking are considered as strongest predictors of parent reported sleep problems.

Effects of exercise on depressive behavior and striatal levels of norepinephrine, serotonin and their metabolites in sleep-deprived mice.

PubMed

Daniele, Thiago Medeiros da Costa; de Bruin, Pedro Felipe Carvalhedo; Rios, Emiliano Ricardo Vasconcelos; de Bruin, Veralice Meireles Sales

2017-08-14

Exercise is a promising adjunctive therapy for depressive behavior, sleep/wake abnormalities, cognition and motor dysfunction. Conversely, sleep deprivation impairs mood, cognition and functional performance. The objective of this study is to evaluate the effects of exercise on anxiety and depressive behavior and striatal levels of norepinephrine (NE), serotonin and its metabolites in mice submitted to 6h of total sleep deprivation (6h-TSD) and 72h of Rapid Eye Movement (REM) sleep deprivation (72h-REMSD). Experimental groups were: (1) mice submitted to 6h-TSD by gentle handling; (2) mice submitted to 72h-REMSD by the flower pot method; (3) exercise (treadmill for 8 weeks); (4) exercise followed by 6h-TSD; (5) exercise followed by 72h-REMSD; (6) control (home cage). Behavioral tests included the Elevated Plus Maze and tail-suspension. NE, serotonin and its metabolites were determined in the striatum using high-performance liquid chromatography (HPLC). Sleep deprivation increased depressive behavior (time of immobilization in the tail-suspension test) and previous exercise hindered it. Sleep deprivation increased striatal NE and previous exercise reduced it. Exercise only was associated with higher levels of serotonin. Furthermore, exercise reduced serotonin turnover associated with sleep deprivation. In brief, previous exercise prevented depressive behavior and reduced striatal high NE levels and serotonin turnover. The present findings confirm the effects of exercise on behavior and neurochemical alterations associated with sleep deprivation. These findings provide new avenues for understanding the mechanisms of exercise. Copyright © 2017 Elsevier B.V. All rights reserved.

Amount of Sleep, Daytime Sleepiness, Hazardous Driving, and Quality of Life of Second Year Medical Students.

PubMed

Johnson, Kay M; Simon, Nancy; Wicks, Mark; Barr, Karen; O'Connor, Kim; Schaad, Doug

2017-10-01

The authors describe the sleep habits of second year medical students and look for associations between reported sleep duration and depression, burnout, overall quality of life, self-reported academic success, and falling asleep while driving. The authors conducted a cross-sectional descriptive study of two consecutive cohorts of second year medical students at a large public university in the USA. Participants completed an anonymous survey about their sleep habits, daytime sleepiness (Epworth sleepiness scale), burnout (Maslach burnout inventory), depression (PRIME MD), and perceived stress (perceived stress scale). Categorical and continuous variables were compared using chi square tests and t tests, respectively. Sixty-eight percent of the students responded. Many (34.3%) reported fewer than 7 h of sleep on typical weeknights, including 6.5% who typically sleep less than 6 h. Twenty-five students (8.4%) reported nodding off while driving during the current academic year. Low typical weeknight sleep (fewer than 6 h vs 6-6.9 h vs 7 or more hours) was associated with (1) higher Epworth sleepiness scale scores, (2) nodding off while driving, (3) symptoms of burnout or depression, (4) decreased satisfaction with quality of life, and (5) lower perceived academic success (all p values ≤0.01). Students reporting under 6 h of sleep were four times more likely to nod off while driving than those reporting 7 h or more. Educational, behavioral, and curricular interventions should be explored to help pre-clinical medical students obtain at least 7 h of sleep most on weeknights.

The benefits of bad economies: Business cycles and time-based work-life conflict.

PubMed

Barnes, Christopher M; Lefter, Alexandru M; Bhave, Devasheesh P; Wagner, David T

2016-04-01

Recent management research has indicated the importance of family, sleep, and recreation as nonwork activities of employees. Drawing from entrainment theory, we develop an expanded model of work-life conflict to contend that macrolevel business cycles influence the amount of time employees spend on both work and nonwork activities. Focusing solely on working adults, we test this model in a large nationally representative dataset from the Bureau of Labor Statistics that spans an 8-year period, which includes the "Great Recession" from 2007 through 2009. We find that during economic booms, employees work more and therefore spend less time with family, sleeping, and recreating. In contrast, in recessionary economies, employees spend less time working and therefore more time with family, sleeping, and recreating. Thus, we extend the theory on time-based work-to-family conflict, showing that there are potential personal and relational benefits for employees in recessionary economies. (c) 2016 APA, all rights reserved).

Common meanings of good and bad sleep in a healthy population sample.

PubMed

Dickerson, Suzanne S; Klingman, Karen J; Jungquist, Carla R

2016-09-01

The study's purpose was to understand the common meanings and shared practices related to good and bad sleep from narratives of a sample of healthy participants. Interpretive phenomenology was the approach to analyze narratives of the participants' everyday experiences with sleep. Participants were interviewed and asked to describe typical good and bad nights' sleep, what contributes to their sleep experience, and the importance of sleep in their lives. Team interpretations of narratives identified common themes by consensus. Medium sized city in New York State (upper west region). A sample of 30 healthy participants were from a parent study (n=300) on testing the sleep questions from the Behavioral Risk Factor Surveillance System from the Centers for Disease Control and Prevention. Interpretations of good and bad sleep. Participants described similar experiences of good and bad sleep often directly related to their ability to schedule time to sleep, fall asleep, and maintain sleep. Worrying about life stresses and interruptions prevented participants from falling asleep and staying asleep. Yet, based on current life priorities (socializers, family work focused, and optimum health seekers), they had differing values related to seeking sleep opportunities and strategizing to overcome challenges. The participants' priorities reflected the context of their main concerns and stresses in life that influenced the importance given to promoting sleep opportunities. Public health messages tailored to life priorities could be developed to promote healthy sleep practices. Copyright © 2016 National Sleep Foundation. Published by Elsevier Inc. All rights reserved.

Entopeduncular nucleus endocannabinoid system modulates sleep-waking cycle and mood in rats.

PubMed

Méndez-Díaz, Mónica; Caynas-Rojas, Seraid; Arteaga Santacruz, Vianney; Ruiz-Contreras, Alejandra E; Aguilar-Roblero, Raúl; Prospéro-García, Oscar

2013-06-01

Since the pioneering work of Gadea-Ciria (Gadea-Ciria M, Stadler H, Lloyd KG, Bartholini G. Acetylcholine release within the cat striatum during the sleep-wakefulness cycle. Nature 1973; 243:518-519) indicating pointing to the involvement of acetylcholine and basal ganglia in sleep regulation; extensive literature has suggested that this brain complex participates in the control of the sleep-waking cycle (SWC). On the other hand, it has been demonstrated that the endocannabinoid system (eCBS) is prominently involved in the regulation of the SWC, mood and its related disorders. Since cannabinoid receptor 1 (CB1R) is highly expressed in basal ganglia, in particular in the entopeduncular nucleus (EP), we believe that it is important to know what the role of the EP CB1R is on SWC, depression, and anxiety. To provide insight into the role of the EP CB1R in the regulation of wakefulness (W), non-rapid eye movement sleep (NREMs) and rapid eye movement sleep (REMs), rats were recorded for 24h immediately after a single intra-EP administration of N-arachidonoylethanolamine (AEA) or 1-(2,4-dichlorophenyl)-5-(4-iodophenyl)-4-methyl-N-(1-piperidyl)pyrazole-3-carboxamide (AM251; CB1 inverse agonist). Likewise, the effect of these drugs on anxiety and depression was tested by means of the elevated plus maze (EPM) and forced swim test (FST), respectively. Results demonstrate that AEA increases NREMs expression, while AM251 increases W and decreases both NREMs and REMs. In addition, administration of AM251 decreases the time rats spent in the open arms and increases immobility time in the FST. It seems that activation of the CB1R in the EP is important to induce sleep, while its blockade promotes W, as well as anxiety and depression, somewhat resembling insomnia in humans. These results suggest that the EP CB1R is modulating sleep and mood. Copyright © 2013 Elsevier Inc. All rights reserved.

Screening for Anger and Sleep Difficulties.

PubMed

Steele, Nicole M; Fogarty, Gerard J

2017-03-01

Mental health screens are designed to detect individuals at risk of psychological disorders. In the military setting of this study, these disorders were post-traumatic stress disorder (PTSD) and alcohol use. This study extends the literature on deployment-related mental health screening by including measures of sleep difficulties and anger as predictors of postdeployment PTSD and alcohol abuse. Evidence that measures of anger and sleep difficulties contribute incremental validity to the prediction of postdeployment mental health problems, including substance abuse, would be helpful in designing interventions to assist the rehabilitation of returning personnel. A test battery containing the PTSD Checklist-Civilian (PCL-C) to screen for PTSD, the Kessler 10 to screen for psychological distress, a Sleep Difficulties scale, an exposure to trauma scale, and an anger scale was administered to 212 personnel nearing completion of a deployment to the Middle East. A second battery containing the PCL-C, the Kessler 10, and a measure of alcohol consumption (Alcohol Use Disorders Identification Test [AUDIT]) was administered to the same personnel 3 to 6 months after return to Australia. Hierarchical regression analyses assessed the predictive validity of measures of psychological distress (anxiety and depression), PTSD symptomatology, sleep disturbance, and anger in relation to postdeployment measures of PTSD symptomatology and alcohol use. Time 1 measures predicted 24.4% of the variance in postdeployment PCL-C scores and 13.1% of the variance in AUDIT scores, with the Sleep Difficulties scale contributing to the prediction of the PCL-C score and the anger scale helping to predict AUDIT scores. On the basis of these findings, we recommend the inclusion of improved measures of both anger and sleep difficulties in end-of-deployment mental health screens. A less behaviorally specific and more wide-ranging anger scale is recommended for future studies that aim to evaluate the role of anger in screening batteries. Our findings suggest that the Sleep Difficulties scale used in this study would be a worthwhile addition to mental health screening because it is moderately correlated with both Time 1 and Time 2 measures of PTSD symptomatology and psychological distress. Furthermore, there is minimal stigma associated with the experience of sleep difficulties. Reprint & Copyright © 2017 Association of Military Surgeons of the U.S.

Behavioral sleep-wake homeostasis and EEG delta power are decoupled by chronic sleep restriction in the rat.

PubMed

Stephenson, Richard; Caron, Aimee M; Famina, Svetlana

2015-05-01

Chronic sleep restriction (CSR) is prevalent in society and is linked to adverse consequences that might be ameliorated by acclimation of homeostatic drive. This study was designed to test the hypothesis that the sleep-wake homeostat will acclimatize to CSR. A four-parameter model of proportional control was used to quantify sleep homeostasis with and without recourse to a sleep intensity function. Animal laboratory, rodent walking-wheel apparatus. Male Sprague-Dawley rats. Acute total sleep deprivation (TSD, 1 day × 18 or 24 h, N = 12), CSR (10 days × 18 h TSD, N = 5, or 5 days × 20 h TSD, N = 6). Behavioral rebounds were consistent with model predictions for proportional control of cumulative times in wake, nonrapid eye movement (NREM) and rapid eye movement (REM). Delta (D) energy homeostasis was secondary to behavioral homeostasis; a biphasic NREM D power rebound contributed to the dynamics (rapid response) but not to the magnitude of the rebound in D energy. REM behavioral homeostasis was little affected by CSR. NREM behavioral homeostasis was attenuated in proportion to cumulative NREM deficit, whereas the biphasic NREM D power rebound was only slightly suppressed, indicating decoupled regulatory mechanisms following CSR. We conclude that sleep homeostasis is achieved through behavioral regulation, that the NREM behavioral homeostat is susceptible to attenuation during CSR and that the concept of sleep intensity is not essential in a model of sleep-wake regulation. Chronic sleep restriction (CSR) is prevalent in society and is linked to adverse consequences that might be ameliorated by acclimation of homeostatic drive. This study was designed to test the hypothesis that the sleep-wake homeostat will acclimatize to CSR. A four-parameter model of proportional control was used to quantify sleep homeostasis with and without recourse to a sleep intensity function. Animal laboratory, rodent walking-wheel apparatus. Male Sprague-Dawley rats. Acute total sleep deprivation (TSD, 1 day × 18 or 24 h, N = 12), CSR (10 days × 18 h TSD, N = 5, or 5 days × 20 h TSD, N = 6). Behavioral rebounds were consistent with model predictions for proportional control of cumulative times in wake, nonrapid eye movement (NREM) and rapid eye movement (REM). Delta (D) energy homeostasis was secondary to behavioral homeostasis; a biphasic NREM D power rebound contributed to the dynamics (rapid response) but not to the magnitude of the rebound in D energy. REM behavioral homeostasis was little affected by CSR. NREM behavioral homeostasis was attenuated in proportion to cumulative NREM deficit, whereas the biphasic NREM D power rebound was only slightly suppressed, indicating decoupled regulatory mechanisms following CSR. We conclude that sleep homeostasis is achieved through behavioral regulation, that the NREM behavioral homeostat is susceptible to attenuation during CSR and that the concept of sleep intensity is not essential in a model of sleep-wake regulation. © 2015 Associated Professional Sleep Societies, LLC.

The efficacy of a restart break for recycling with optimal performance depends critically on circadian timing.

PubMed

Van Dongen, Hans P A; Belenky, Gregory; Vila, Bryan J

2011-07-01

Under simulated shift-work conditions, we investigated the efficacy of a restart break for maintaining neurobehavioral functioning across consecutive duty cycles, as a function of the circadian timing of the duty periods. As part of a 14-day experiment, subjects underwent two cycles of five simulated daytime or nighttime duty days, separated by a 34-hour restart break. Cognitive functioning and high-fidelity driving simulator performance were tested 4 times per day during the two duty cycles. Lapses on a psychomotor vigilance test (PVT) served as the primary outcome variable. Selected sleep periods were recorded polysomnographically. The experiment was conducted under standardized, controlled laboratory conditions with continuous monitoring. Twenty-seven healthy adults (13 men, 14 women; aged 22-39 years) participated in the study. Subjects were randomly assigned to a nighttime duty (experimental) condition or a daytime duty (control) condition. The efficacy of the 34-hour restart break for maintaining neurobehavioral functioning from the pre-restart duty cycle to the post-restart duty cycle was compared between these two conditions. Relative to the daytime duty condition, the nighttime duty condition was associated with reduced amounts of sleep, whereas sleep latencies were shortened and slow-wave sleep appeared to be conserved. Neurobehavioral performance measures ranging from lapses of attention on the PVT to calculated fuel consumption on the driving simulators remained optimal across time of day in the daytime duty schedule, but degraded across time of night in the nighttime duty schedule. The 34-hour restart break was efficacious for maintaining PVT performance and other objective neurobehavioral functioning profiles from one duty cycle to the next in the daytime duty condition, but not in the nighttime duty condition. Subjective sleepiness did not reliably track objective neurobehavioral deficits. The 34-hour restart break was adequate for maintaining performance in the case of optimal circadian placement of sleep and duty periods (control condition) but was inadequate (and perhaps even detrimental) for maintaining performance in a simulated nighttime duty schedule (experimental condition). Current US transportation hours-of-service regulations mandate time off duty but do not consider the circadian aspects of shift scheduling. Reinforcing a recent trend of applying sleep science to inform policymaking for duty and rest times, our findings indicate that restart provisions in hours-of-service regulations could be improved by taking the circadian timing of the duty schedules into account.

Sleeping Habits among School Children and their Effects on Sleep Pattern.

PubMed

Mishra, Apurva; Pandey, Ramesh Kumar; Minz, Anurag; Arora, Varuni

2017-12-01

Introduction: Sleep problems can occur at any age. Inadequate sleep affects the physiological as well as psychological well-being of an individual. Thus, the objective of the present study is, to determine the pre sleep habits, duration and pattern of sleep among school children and to determine association between their sleep schedules and sleep habits. Methods: This cross-sectional study comprised of 1050 children attending the government school. Based on inclusion and exclusion criteria children were from three age groups: 4-5 years, 6-10 years and 11-15 years of age. A questionnaire about demographical data, sleep problems and habits, was duly filled by the parents. The parents of children were questioned for bed time, wakeup time, sleep time and sleep duration during both weekdays and weekends. Results: Total sleep time during weekdays was 8.9 (1.2) hours and 10.7 (1.1) hours during weekends. The wakeup time was significantly delayed during weekends in all age groups. Moreover, total sleep time increased significantly during weekends in all age groups. Children using media after 8 pm and sleeping alone are also in significant sleep debt. Screen activities such as TV, internet and cellular phones in a child's bedroom had a negative effect on children's sleep/wake patterns and duration of sleep. Children in higher grades are sleep debt compared to younger ones. Practices such as co sleeping and sharing bed with parents significantly improve the duration and quality of sleep. Conclusion: The sleep durations reported in the present study were lower than recommended sleep duration for children.

Sleep Disorders in Aboriginal and Torres Strait Islander People and Residents of Regional and Remote Australia

PubMed Central

Woods, Cindy E.; McPherson, Karen; Tikoft, Erik; Usher, Kim; Hosseini, Fariborz; Ferns, Janine; Jersmann, Hubertus; Antic, Ral; Maguire, Graeme Paul

2015-01-01

Study Objectives: To compare the use of sleep diagnostic tests, the risks, and cofactors, and outcomes of the care of Indigenous and non-indigenous Australian adults in regional and remote Australia in whom sleep related breathing disorders have been diagnosed. Methods: A retrospective cohort study of 200 adults; 100 Aboriginal and Torres Strait Islander and 100 non-indigenous adults with a confirmed sleep related breathing disorder diagnosed prior to September 2011 at Alice Springs Hospital and Cairns Hospital, Australia. Results: Results showed overall Indigenous Australians were 1.8 times more likely to have a positive diagnostic sleep study performed compared with non-indigenous patients, 1.6 times less likely in central Australia and 3.4 times more likely in far north Queensland. All regional and remote residents accessed diagnostic sleep studies at a rate less than Australia overall (31/100,000/y (95% confidence interval, 21–44) compared with 575/100,000/y). Conclusion: The barriers to diagnosis and ongoing care are likely to relate to remote residence, lower health self-efficacy, the complex nature of the treatment tool, and environmental factors such as electricity and sleeping area. Indigeneity, remote residence, environmental factors, and low awareness of sleep health are likely to affect service accessibility and rate of use and capacity to enhance patient and family education and support following a diagnosis. A greater understanding of enablers and barriers to care and evaluation of interventions to address these are required. Commentary: A commentary on this article appears in this issue on page 1255. Citation: Woods CE, McPherson K, Tikoft E, Usher K, Hosseini F, Ferns J, Jersmann H, Antic R, Maguire GP. Sleep disorders in Aboriginal and Torres Strait Islander people and residents of regional and remote Australia. J Clin Sleep Med 2015;11(11):1263–1271. PMID:26094934

Increased Automaticity and Altered Temporal Preparation Following Sleep Deprivation

PubMed Central

Kong, Danyang; Asplund, Christopher L.; Ling, Aiqing; Chee, Michael W.L.

2015-01-01

Study Objectives: Temporal expectation enables us to focus limited processing resources, thereby optimizing perceptual and motor processing for critical upcoming events. We investigated the effects of total sleep deprivation (TSD) on temporal expectation by evaluating the foreperiod and sequential effects during a psychomotor vigilance task (PVT). We also examined how these two measures were modulated by vulnerability to TSD. Design: Three 10-min visual PVT sessions using uniformly distributed foreperiods were conducted in the wake-maintenance zone the evening before sleep deprivation (ESD) and three more in the morning following approximately 22 h of TSD. TSD vulnerable and nonvulnerable groups were determined by a tertile split of participants based on the change in the number of behavioral lapses recorded during ESD and TSD. A subset of participants performed six additional 10-min modified auditory PVTs with exponentially distributed foreperiods during rested wakefulness (RW) and TSD to test the effect of temporal distribution on foreperiod and sequential effects. Setting: Sleep laboratory. Participants: There were 172 young healthy participants (90 males) with regular sleep patterns. Nineteen of these participants performed the modified auditory PVT. Measurements and Results: Despite behavioral lapses and slower response times, sleep deprived participants could still perceive the conditional probability of temporal events and modify their level of preparation accordingly. Both foreperiod and sequential effects were magnified following sleep deprivation in vulnerable individuals. Only the foreperiod effect increased in nonvulnerable individuals. Conclusions: The preservation of foreperiod and sequential effects suggests that implicit time perception and temporal preparedness are intact during total sleep deprivation. Individuals appear to reallocate their depleted preparatory resources to more probable event timings in ongoing trials, whereas vulnerable participants also rely more on automatic processes. Citation: Kong D, Asplund CL, Ling A, Chee MWL. Increased automaticity and altered temporal preparation following sleep deprivation. SLEEP 2015;38(8):1219–1227. PMID:25845689

Scheduled evening sleep and enhanced lighting improve adaptation to night shift work in older adults.

PubMed

Chinoy, Evan D; Harris, Michael P; Kim, Min Ju; Wang, Wei; Duffy, Jeanne F

2016-12-01

We tested whether a sleep and circadian-based treatment shown to improve circadian adaptation to night shifts and attenuate negative effects on alertness, performance and sleep in young adults would also be effective in older adults. We assessed subjective alertness, sustained attention (psychomotor vigilance task, PVT), sleep duration (actigraphy) and circadian timing (salivary dim-light melatonin onset, DLMO) in 18 older adults (57.2±3.8 years; mean±SD) in a simulated shift work protocol. 4 day shifts were followed by 3 night shifts in the laboratory. Participants slept at home and were randomised to either the treatment group (scheduled evening sleep and enhanced lighting during the latter half of night shifts) or control group (ad-lib sleep and typical lighting during night shifts). Compared with day shifts, alertness and sustained attention declined on the first night shift in both groups, and was worse in the latter half of the night shifts. Alertness and attention improved on nights 2 and 3 for the treatment group but remained lower for the control group. Sleep duration in the treatment group remained similar to baseline (6-7 hours) following night shifts, but was shorter (3-5 hours) following night shifts in the control group. Treatment group circadian timing advanced by 169.3±16.1 min (mean±SEM) but did not shift (-9.7±9.9 min) in the control group. The combined treatment of scheduled evening sleep and enhanced lighting increased sleep duration and partially aligned circadian phase with sleep and work timing, resulting in improved night shift alertness and performance. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

Test Expectation Enhances Memory Consolidation across Both Sleep and Wake

PubMed Central

Wamsley, Erin J.; Hamilton, Kelly; Graveline, Yvette; Manceor, Stephanie; Parr, Elaine

2016-01-01

Memory consolidation benefits from post-training sleep. However, recent studies suggest that sleep does not uniformly benefit all memory, but instead prioritizes information that is important to the individual. Here, we examined the effect of test expectation on memory consolidation across sleep and wakefulness. Following reports that information with strong “future relevance” is preferentially consolidated during sleep, we hypothesized that test expectation would enhance memory consolidation across a period of sleep, but not across wakefulness. To the contrary, we found that expectation of a future test enhanced memory for both spatial and motor learning, but that this effect was equivalent across both wake and sleep retention intervals. These observations differ from those of least two prior studies, and fail to support the hypothesis that the “future relevance” of learned material moderates its consolidation selectively during sleep. PMID:27760193

The effects of sleep deprivation on emotional empathy.

PubMed

Guadagni, Veronica; Burles, Ford; Ferrara, Michele; Iaria, Giuseppe

2014-12-01

Previous studies have shown that sleep loss has a detrimental effect on the ability of the individuals to process emotional information. In this study, we tested the hypothesis that this negative effect extends to the ability of experiencing emotions while observing other individuals, i.e. emotional empathy. To test this hypothesis, we assessed emotional empathy in 37 healthy volunteers who were assigned randomly to one of three experimental groups: one group was tested before and after a night of total sleep deprivation (sleep deprivation group), a second group was tested before and after a usual night of sleep spent at home (sleep group) and the third group was tested twice during the same day (day group). Emotional empathy was assessed by using two parallel versions of a computerized test measuring direct (i.e. explicit evaluation of empathic concern) and indirect (i.e. the observer's reported physiological arousal) emotional empathy. The results revealed that the post measurements of both direct and indirect emotional empathy of participants in the sleep deprivation group were significantly lower than those of the sleep and day groups; post measurement scores of participants in the day and sleep groups did not differ significantly for either direct or indirect emotional empathy. These data are consistent with previous studies showing the negative effect of sleep deprivation on the processing of emotional information, and extend these effects to emotional empathy. The findings reported in our study are relevant to healthy individuals with poor sleep habits, as well as clinical populations suffering from sleep disturbances. © 2014 European Sleep Research Society.

Modifiable predictors of insufficient sleep durations: A longitudinal analysis of youth in the COMPASS study.

PubMed

Patte, Karen A; Qian, Wei; Leatherdale, Scott T

2018-01-01

The purpose of the current study was to simultaneously examine commonly proposed risk and protective factors for sleep deprivation over time among a large cohort of Ontario and Alberta secondary school students. Using 4-year linked longitudinal data from youth in years 1 through 4 (Y 1 [2012/2013], Y 2 [2013/2014], Y 3 [2014/2015], Y 4 [2015/2016]) of the COMPASS study (n=26,205), the likelihood of students meeting contemporary sleep recommendations was tested based on their self-reported substance use, bullying victimization, physical activity, and homework and screen time. Models controlled for the effect of student-reported gender, race/ethnicity, grade, school clustering, and all other predictor variables. Relative to baseline, students became less likely to meet the sleep recommendations if at follow-up they had initiated binge drinking, experienced cyber bullying victimization, or were spending more time doing homework, with other factors held constant. The likelihood of reporting sufficient sleep increased if students had begun engaging in resistance training at least three times a week. No longitudinal effect was observed when students increased their caffeine consumption (energy drinks, coffee/tea), initiated cannabis or tobacco use, experienced other forms of bullying victimization (physical, verbal, or belongings), engaged in more moderate-vigorous physical activity, or increased their screen use of any type. Few of the commonly purported modifiable risk and protective factors for youth sleep deprivation held in multinomial longitudinal analyses. Causal conclusions appear premature, with further research required to confirm the targets likely to be most effective in assisting more youth in meeting the sleep recommendations. Copyright © 2017 Elsevier Inc. All rights reserved.

Using Repeated Measures of Sleep Disturbances to Predict Future Diagnosis-Specific Work Disability: A Cohort Study

PubMed Central

Salo, Paula; Vahtera, Jussi; Hall, Martica; Rod, Naja Hulvej; Virtanen, Marianna; Pentti, Jaana; Sjösten, Noora; Oksanen, Tuula; Kivimäki, Mika

2012-01-01

Context: It is unknown whether or not measuring sleep disturbances repeatedly, rather than at only one point in time, improves prediction of work disability. Study Objective: o examine sleep disturbance patterns over time as a risk marker for diagnosis-specific work disability. Design: rospective cohort study linking repeatedly measured self-reported sleep disturbances with records of physician-certified work disability (sickness absence) from a national register. Participants responded to surveys in 2000–2002, and 2004, and were followed up for 12 mo. Setting: Public sector employees in Finland. Participants: 25,639 participants (mean age 45.6 yr, 82% female). Main Outcome Measure: Incident diagnosis-specific sickness absence of > 9 days. Results: During a mean follow-up of 323 days, 4,975 employees (19%) had a new episode of sickness absence. In multivariable-adjusted models corrected for multiple testing, stable severe sleep disturbances, in comparison with no sleep disturbances, were associated with an increased risk of sickness absence due to diseases of the musculoskeletal system (hazard ratio (HR) 1.68, 95% confidence interval (CI) 1.45–1.95), and injuries and poisonings (HR 1.64, 95% CI 1.23–2.18). Increases in sleep disturbances predicted subsequent sickness absence due to mental disorders (HR 1.59, 95% CI 1.32–1.91), and diseases of the musculoskeletal system (HR 1.44, 95% CI 1.27–1.64) According to net reclassification improvement analyses, measurement of sleep disturbance patterns rather than the level of sleep disturbances at one point in time improved prediction of all-cause sickness absence by 14%, and diagnosis-specific sickness absences up to 17% (P for improvement < 0.001). Conclusions: Increasing and severe chronic sleep disturbances mark an increased risk of diagnosis-specific work disability. Citation: Salo P; Vahtera J; Hall M; Rod NH; Virtanen M; Pentti J; Sjösten N; Oksanen T; Kivimäki M. Using repeated measures of sleep disturbances to predict future diagnosis-specific work disability: a cohort study. SLEEP 2012;35(4):559-569. PMID:22467994

Crew factors in flight operations. 8: Factors influencing sleep timing and subjective sleep quality in commercial long-haul flight crews

NASA Technical Reports Server (NTRS)

Gander, Philippa H.; Graeber, R. Curtis; Connell, Linda J.; Gregory, Kevin B.

1991-01-01

How flight crews organize their sleep during layovers on long-haul trips is documented. Additionally, environmental and physiological constraints on sleep are examined. In the trips studied, duty periods averaging 10.3 hr alternated with layovers averaging 24.8 hr, which typically included two subject-defined sleep episodes. The circadian system had a greater influence on the timing and duration of first-sleeps than second-sleeps. There was also a preference for sleeping during the local night. The time of falling asleep for second-sleeps was related primarily to the amount of sleep already obtained in the layover, and their duration depended on the amount of time remaining in the layover. For both first- and second-sleeps, sleep durations were longer when subjects fell asleep earlier with respect to the minimum of the circadian temperature cycle. Naps reported during layovers and on the flight deck may be a useful strategy for reducing cumulative sleep loss. The circadian system was not able to synchronize with the rapid series of time-zone shifts. The sleep/wake cycle was forced to adopt a period different from that of the circadian system. Flight and duty time regulations are a means of ensuring that reasonable minimum rest periods are provided. This study clearly documents that there are physiologically and environmentally determined preferred sleep times within a layover. The actual time available for sleep is thus less than the scheduled rest period.

Relationship Between Short Sleep Duration and Preseason Concussion Testing.

PubMed

Silverberg, Noah D; Berkner, Paul D; Atkins, Joseph E; Zafonte, Ross; Iverson, Grant L

2016-05-01

Baseline, preseason assessment of cognition, symptoms, and balance has been recommended as part of a comprehensive sport concussion management program. We examined the relationship between sleep and baseline test results. We hypothesized that adolescents who slept fewer hours the night before would report more symptoms and perform more poorly on cognitive testing than students who had a full night sleep. Cross-sectional observation study. Preseason concussion testing for high school athletes. A large sample (n = 2928) of student athletes from Maine, USA, between the ages of 13 and 18 years completed preseason testing. Participants with developmental problems, a history of treatment for neurological or psychiatric problems, recent concussion, or 3 or more prior concussions were excluded. Athletes were divided into 4 groups based on their sleep duration the night before testing. Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT; ImPACT Applications, Inc, Pittsburgh, PA) cognitive composite scores and the embedded Post-Concussion Symptom Scale. Sleep was not related to any ImPACT cognitive composite score, after covarying for age and controlling for multiple comparisons. In contrast, there were sleep duration, sex, and sleep duration by sex effects on the Post-Concussion Symptom Scale. The effect of sleep duration on symptom reporting was more pronounced in girls. Supplementary analyses suggested that sleep insufficiency was associated with a diverse array of postconcussion-like symptoms. Poor sleep the night before baseline or postinjury testing may be an important confound when assessing postconcussion symptoms. Girls may be more vulnerable to experiencing and reporting symptoms following insufficient sleep. Clinicians should routinely ask how the athlete slept the night before preseason baseline testing and consider deferring the symptom assessment or later retesting athletes who slept poorly.

Sensitivity of the stanford sleepiness scale to the effects of cumulative partial sleep deprivation and recovery oversleeping.

PubMed

Herscovitch, J; Broughton, R

1981-01-01

The sensitivity of the Stanford Sleepiness Scale (SSS) to short-term cumulative partial sleep deprivation (PSD) and subsequent recovery oversleeping was examined. A repeated-measures design included 7 paid healthy undergraduate volunteers, who were normal sleepers (mean sleep time 7.6 hr), and consisted of the following schedule: (a) pre-baseline; (b)sleep reduction of 40% of 1 night (mean, 4.6 hr) for 5 nights; (c) recovery oversleeping for night 1 (mean, 10.6 Hr) and night 2 (mean, 9.1 hr); (d) post-baseline. Daytime performance testing utilized a 1 hr auditory vigilance task and four short-duration (10 min) tests, two of which have been shown sensitive to total and partial sleep loss effects. Subjects completed SSS forms every min while awake and 1-9 scales of mood and energy upon awakening. Subjective measures were analyzed across conditions for mean all-day and task-related SSS values and mood and energy ratings. A correlational analysis investigated individual correspondences between ratings and performance. Results indicate that SSS is sensitive to deficits in alertness following PSD. However, it generally does not predict individual performance efficiency and therefore cannot act as a substitute for performance measures in studies involving chronic sleep loss.

Sleep deprivation selectively disrupts top-down adaptation to cognitive conflict in the Stroop test.

PubMed

Gevers, Wim; Deliens, Gaetane; Hoffmann, Sophie; Notebaert, Wim; Peigneux, Philippe

2015-12-01

Sleep deprivation is known to exert detrimental effects on various cognitive domains, including attention, vigilance and working memory. Seemingly at odds with these findings, prior studies repeatedly failed to evidence an impact of prior sleep deprivation on cognitive interference in the Stroop test, a hallmark paradigm in the study of cognitive control abilities. The present study investigated further the effect of sleep deprivation on cognitive control using an adapted version of the Stroop test that allows to segregate top-down (attentional reconfiguration on incongruent items) and bottom-up (facilitated processing after repetitions in responses and/or features of stimuli) components of performance. Participants underwent a regular night of sleep or a night of total sleep deprivation before cognitive testing. Results disclosed that sleep deprivation selectively impairs top-down adaptation mechanisms: cognitive control no longer increased upon detection of response conflict at the preceding trial. In parallel, bottom-up abilities were found unaffected by sleep deprivation: beneficial effects of stimulus and response repetitions persisted. Changes in vigilance states due to sleep deprivation selectively impact on cognitive control in the Stroop test by affecting top-down, but not bottom-up, mechanisms that guide adaptive behaviours. © 2015 European Sleep Research Society.

The effects of slow-wave sleep (SWS) deprivation and time of night on behavioral performance upon awakening.

PubMed

Ferrara, M; De Gennaro, L; Bertini, M

The aim of the present study is to evaluate the effects of selective SWS deprivation on the motor and sensory motor performance impairment immediately after awakening from nocturnal sleep at different times of the night. Ten normal males slept for 6 consecutive nights in the laboratory: one adaptation, two baseline, two selective SWS deprivation, and one recovery night. During the last 4 nights performance was assessed four times: (a) before sleep, as a baseline measure; (b) within 30 s from the first nighttime awakening, after 2 h of sleep; (c) within 30 s from the second nighttime awakening, after 5 h of sleep; (d) within 30 s from the final morning awakening. After each awakening, following a 3-min cognitive test, a simple Auditory Reaction Time task (ART, about 5 min) and a Finger Tapping Task (FTT, 3 min) were administered. Median of Reaction Times (RT) and of Intertapping Intervals (ITI), 10% fastest RT, 10% slowest RT, and number of misses were considered as dependent variables. The selective SWS deprivation was very effective: SWS percentage during both the deprivation nights was close to zero. This strong manipulation of SWS amount interacted with time-of-night factors in influencing sleep inertia. The SWS deprivation procedure caused a worsening of behavioral performance during the deprivation nights. as well as upon the final awakening of the recovery night. Behavioral performance slowing upon awakening is accounted for by: (1) a general decrement in overall response speed (median of RT); (2) an "optimum response shift", i.e., a decrease in speed of the fastest responses; (3) an increase of lapsing, with more marked response delays resulting in a further decrease in response speed in the "lapse domain". Finally, our results do not support the existence of a circadian rhythm of sleep inertia linked to body temperature rhythm.

Sustained attention performance during sleep deprivation: evidence of state instability

NASA Technical Reports Server (NTRS)

Doran, S. M.; Van Dongen, H. P.; Dinges, D. F.

2001-01-01

Nathaniel Kleitman was the first to observe that sleep deprivation in humans did not eliminate the ability to perform neurobehavioral functions, but it did make it difficult to maintain stable performance for more than a few minutes. To investigate variability in performance as a function of sleep deprivation, n = 13 subjects were tested every 2 hours on a 10-minute, sustained-attention, psychomotor vigilance task (PVT) throughout 88 hours of total sleep deprivation (TSD condition), and compared to a control group of n = 15 subjects who were permitted a 2-hour nap every 12 hours (NAP condition) throughout the 88-hour period. PVT reaction time means and standard deviations increased markedly among subjects and within each individual subject in the TSD condition relative to the NAP condition. TSD subjects also had increasingly greater performance variability as a function of time on task after 18 hours of wakefulness. During sleep deprivation, variability in PVT performance reflected a combination of normal timely responses, errors of omission (i.e., lapses), and errors of commission (i.e., responding when no stimulus was present). Errors of omission and errors of commission were highly intercorrelated across deprivation in the TSD condition (r = 0.85, p = 0.0001), suggesting that performance instability is more likely to include compensatory effort than a lack of motivation. The marked increases in PVT performance variability as sleep loss continued supports the "state instability" hypothesis, which posits that performance during sleep deprivation is increasingly variable due to the influence of sleep initiating mechanisms on the endogenous capacity to maintain attention and alertness, thereby creating an unstable state that fluctuates within seconds and that cannot be characterized as either fully awake or asleep.

Coordination of Slow Waves With Sleep Spindles Predicts Sleep-Dependent Memory Consolidation in Schizophrenia.

PubMed

Demanuele, Charmaine; Bartsch, Ullrich; Baran, Bengi; Khan, Sheraz; Vangel, Mark G; Cox, Roy; Hämäläinen, Matti; Jones, Matthew W; Stickgold, Robert; Manoach, Dara S

2017-01-01

Schizophrenia patients have correlated deficits in sleep spindle density and sleep-dependent memory consolidation. In addition to spindle density, memory consolidation is thought to rely on the precise temporal coordination of spindles with slow waves (SWs). We investigated whether this coordination is intact in schizophrenia and its relation to motor procedural memory consolidation. Twenty-one chronic medicated schizophrenia patients and 17 demographically matched healthy controls underwent two nights of polysomnography, with training on the finger tapping motor sequence task (MST) on the second night and testing the following morning. We detected SWs (0.5-4 Hz) and spindles during non-rapid eye movement (NREM) sleep. We measured SW-spindle phase-amplitude coupling and its relation with overnight improvement in MST performance. Patients did not differ from controls in the timing of SW-spindle coupling. In both the groups, spindles peaked during the SW upstate. For patients alone, the later in the SW upstate that spindles peaked and the more reliable this phase relationship, the greater the overnight MST improvement. Regression models that included both spindle density and SW-spindle coordination predicted overnight improvement significantly better than either parameter alone, suggesting that both contribute to memory consolidation. Schizophrenia patients show intact spindle-SW temporal coordination, and these timing relationships, together with spindle density, predict sleep-dependent memory consolidation. These relations were seen only in patients suggesting that their memory is more dependent on optimal spindle-SW timing, possibly due to reduced spindle density. Interventions to improve memory may need to increase spindle density while preserving or enhancing the coordination of NREM oscillations. © Sleep Research Society 2016. Published by Oxford University Press on behalf of the Sleep Research Society. All rights reserved. For permissions, please e-mail journals.permissions@oup.com.

How many hours do people sleep in Bangladesh? A country-representative survey.

PubMed

Yunus, Fakir M; Khan, Safayet; Akter, Tahera; Jhohura, Fatema T; Reja, Saifur; Islam, Akramul; Rahman, Mahfuzar

2016-06-01

This study investigated total sleep time in the Bangladeshi population and identified the proportion of the population at greater risk of developing chronic diseases due to inadequate sleep. Using a cross-sectional survey, total sleep time was captured and analysed in 3968 respondents aged between 6 and 106 years in 24 (of 64) districts in Bangladesh. Total sleep time was defined as the hours of total sleep in the previous 24 h. We used National Sleep Foundation (2015) guidelines to determine the recommended sleep hours in different age categories. Less or more than the recommended total sleep time (in hours) was considered 'shorter' and 'longer' sleep time, respectively. Linear and multinomial logistic regression models were used to determine the relationship between demographic variables and estimated risk of shorter and longer total sleep time. The mean (±standard deviation) total sleep time of children (6-13 years), teenagers (14-17 years), young adults and adults (18-64 years) and older adults (≥65 years) were 8.6 (±1.1), 8.1 (±1.0), 7.7 (±0.9) and 7.8 (±1.4) h, respectively, which were significantly different (P < 0.01). More than half of school-age children (55%) slept less than, and 28.2% of older adults slept longer than, recommended. Residents in all divisions (except Chittagong) in Bangladesh were less likely to sleep longer than in the Dhaka division. Rural populations had a 3.96× greater chance of sleeping for a shorter time than urban residents. The Bangladeshi population tends to sleep for longer and/or shorter times than their respective recommended sleep hours, which is detrimental to health. © 2016 European Sleep Research Society.

Neural Basis of Brain Dysfunction Produced by Early Sleep Problems.

PubMed

Kohyama, Jun

2016-01-29

There is a wealth of evidence that disrupted sleep and circadian rhythms, which are common in modern society even during the early stages of life, have unfavorable effects on brain function. Altered brain function can cause problem behaviors later in life, such as truancy from or dropping out of school, quitting employment, and committing suicide. In this review, we discuss findings from several large cohort studies together with recent results of a cohort study using the marshmallow test, which was first introduced in the 1960s. This test assessed the ability of four-year-olds to delay gratification and showed how this ability correlated with success later in life. The role of the serotonergic system in sleep and how this role changes with age are also discussed. The serotonergic system is involved in reward processing and interactions with the dorsal striatum, ventral striatum, and the prefrontal cortex are thought to comprise the neural basis for behavioral patterns that are affected by the quantity, quality, and timing of sleep early in life.

Start Later, Sleep Later: School Start Times and Adolescent Sleep in Homeschool vs. Public/Private School Students

PubMed Central

Meltzer, Lisa J.; Shaheed, Keisha; Ambler, Devon

2014-01-01

Homeschool students provide a naturalistic comparison group for later/flexible school start times. This study compared sleep patterns and sleep hygiene for homeschool students and public/private school students (grades 6-12). Public/private school students (n=245) and homeschool students (n=162) completed a survey about sleep patterns and sleep hygiene. Significant school group differences were found for weekday bedtime, wake time, and total sleep time, with homeschool students waking later and obtaining more sleep. Homeschool students had later school start times, waking at the same time that public/private school students were starting school. Public/private school students had poorer sleep hygiene practices, reporting more homework and use of technology in the hour before bed. Regardless of school type, technology in the bedroom was associated with shorter sleep duration. Later school start times may be a potential countermeasure for insufficient sleep in adolescents. Future studies should further examine the relationship between school start times and daytime outcomes, including academic performance, mood, and health. PMID:25315902

Test-Retest Reliability of the Multiple Sleep Latency Test in Narcolepsy without Cataplexy and Idiopathic Hypersomnia

PubMed Central

Trotti, Lynn Marie; Staab, Beth A.; Rye, David B.

2013-01-01

Study Objectives: Differentiation of narcolepsy without cataplexy from idiopathic hypersomnia relies entirely upon the multiple sleep latency test (MSLT). However, the test-retest reliability for these central nervous system hypersomnias has never been determined. Methods: Patients with narcolepsy without cataplexy, idiopathic hypersomnia, and physiologic hypersomnia who underwent two diagnostic multiple sleep latency tests were identified retrospectively. Correlations between the mean sleep latencies on the two studies were evaluated, and we probed for demographic and clinical features associated with reproducibility versus change in diagnosis. Results: Thirty-six patients (58% women, mean age 34 years) were included. Inter -test interval was 4.2 ± 3.8 years (range 2.5 months to 16.9 years). Mean sleep latencies on the first and second tests were 5.5 (± 3.7 SD) and 7.3 (± 3.9) minutes, respectively, with no significant correlation (r = 0.17, p = 0.31). A change in diagnosis occurred in 53% of patients, and was accounted for by a difference in the mean sleep latency (N = 15, 42%) or the number of sleep onset REM periods (N = 11, 31%). The only feature predictive of a diagnosis change was a history of hypnagogic or hypnopompic hallucinations. Conclusions: The multiple sleep latency test demonstrates poor test-retest reliability in a clinical population of patients with central nervous system hypersomnia evaluated in a tertiary referral center. Alternative diagnostic tools are needed. Citation: Trotti LM; Staab BA; Rye DB. Test- retest reliability of the multiple sleep latency test in narcolepsy without cataplexy and idiopathic hypersomnia. J Clin Sleep Med 2013;9(8):789-795. PMID:23946709

A cross-syndrome study of the differential effects of sleep on declarative memory consolidation in children with neurodevelopmental disorders.

PubMed

Ashworth, Anna; Hill, Catherine M; Karmiloff-Smith, Annette; Dimitriou, Dagmara

2017-03-01

Sleep plays an active role in memory consolidation. Because children with Down syndrome (DS) and Williams syndrome (WS) experience significant problems with sleep and also with learning, we predicted that sleep-dependent memory consolidation would be impaired in these children when compared to typically developing (TD) children. This is the first study to provide a cross-syndrome comparison of sleep-dependent learning in school-aged children. Children with DS (n = 20) and WS (n = 22) and TD children (n = 33) were trained on the novel Animal Names task where they were taught pseudo-words as the personal names of ten farm and domestic animals, e.g. Basco the cat, with the aid of animal picture flashcards. They were retested following counterbalanced retention intervals of wake and sleep. Overall, TD children remembered significantly more words than both the DS and WS groups. In addition, their performance improved following night-time sleep, whereas performance over the wake retention interval remained stable, indicating an active role of sleep for memory consolidation. Task performance of children with DS did not significantly change following wake or sleep periods. However, children with DS who were initially trained in the morning continued to improve on the task at the following retests, so that performance on the final test was greater for children who had initially trained in the morning than those who trained in the evening. Children with WS improved on the task between training and the first retest, regardless of whether sleep or wake occurred during the retention interval. This suggests time-dependent rather than sleep-dependent learning in children with WS, or tiredness at the end of the first session and better performance once refreshed at the start of the second session, irrespective of the time of day. Contrary to expectations, sleep-dependent learning was not related to baseline level of performance. The findings have significant implications for educational strategies, and suggest that children with DS should be taught more important or difficult information in the morning when they are better able to learn, whilst children with WS should be allowed a time delay between learning phases to allow for time-dependent memory consolidation, and frequent breaks from learning so that they are refreshed and able to perform at their best. © 2015 The Authors. Developmental Science Published by John Wiley & Sons Ltd.

Antidepressant-like effects of methanol extract of Hibiscus tiliaceus flowers in mice

PubMed Central

2012-01-01

Background Hibiscus tiliaceus L. (Malvaceae) is used in postpartum disorders. Our purpose was to examine the antidepressant, anxiolytic and sedative actions of the methanol extract of H. tiliaceus flowers using animal models. Methods Adult male Swiss albino mice were treated with saline, standard drugs or methanol extract of H. tiliaceus and then subjected to behavioral tests. The forced swimming and tail suspension tests were used as predictive animal models of antidepressant activity, where the time of immobility was considered. The animals were submitted to the elevated plus-maze and ketamine-induced sleeping time to assess anxiolytic and sedative activities, respectively. Results Methanol extract of H. tiliaceus significantly decreased the duration of immobility in both animal models of antidepressant activity, forced swimming and tail suspension tests. This extract did not potentiate the effect of ketamine-induced hypnosis, as determined by the time to onset and duration of sleeping time. Conclusion Our results indicate an antidepressant-like profile of action for the extract of Hibiscus tiliaceus without sedative side effect. PMID:22494845

Chronic Low Quality Sleep Impairs Postural Control in Healthy Adults.

PubMed

Furtado, Fabianne; Gonçalves, Bruno da Silva B; Abranches, Isabela Lopes Laguardia; Abrantes, Ana Flávia; Forner-Cordero, Arturo

2016-01-01

The lack of sleep, both in quality and quantity, is an increasing problem in modern society, often related to workload and stress. A number of studies have addressed the effects of acute (total) sleep deprivation on postural control. However, up to date, the effects of chronic sleep deficits, either in quantity or quality, have not been analyzed. Thirty healthy adults participated in the study that consisted of registering activity with a wrist actigraph for more than a week before performing a series of postural control tests. Sleep and circadian rhythm variables were correlated and the sum of activity of the least active 5-h period, L5, a rhythm variable, obtained the greater coefficient value with sleep quality variables (wake after sleep onset WASO and efficiency sleep). Cluster analysis was performed to classify subjects into two groups based on L5 (low and high). The balance tests scores used to asses postural control were measured using Biodex Balance System and were compared between the two groups with different sleep quality. The postural tests were divided into dynamic (platform tilt with eyes open, closed and cursor) and static (clinical test of sensory integration). The results showed that during the tests with eyes closed, the group with worse sleep quality had also worse postural control performance. Lack of vision impairs postural balance more deeply in subjects with chronic sleep inefficiency. Chronic poor sleep quality impairs postural control similarly to total sleep deprivation.

Chronic Low Quality Sleep Impairs Postural Control in Healthy Adults

PubMed Central

Gonçalves, Bruno da Silva B.; Abranches, Isabela Lopes Laguardia; Abrantes, Ana Flávia

2016-01-01

The lack of sleep, both in quality and quantity, is an increasing problem in modern society, often related to workload and stress. A number of studies have addressed the effects of acute (total) sleep deprivation on postural control. However, up to date, the effects of chronic sleep deficits, either in quantity or quality, have not been analyzed. Thirty healthy adults participated in the study that consisted of registering activity with a wrist actigraph for more than a week before performing a series of postural control tests. Sleep and circadian rhythm variables were correlated and the sum of activity of the least active 5-h period, L5, a rhythm variable, obtained the greater coefficient value with sleep quality variables (wake after sleep onset WASO and efficiency sleep). Cluster analysis was performed to classify subjects into two groups based on L5 (low and high). The balance tests scores used to asses postural control were measured using Biodex Balance System and were compared between the two groups with different sleep quality. The postural tests were divided into dynamic (platform tilt with eyes open, closed and cursor) and static (clinical test of sensory integration). The results showed that during the tests with eyes closed, the group with worse sleep quality had also worse postural control performance. Lack of vision impairs postural balance more deeply in subjects with chronic sleep inefficiency. Chronic poor sleep quality impairs postural control similarly to total sleep deprivation. PMID:27732604

Diagnosis and management of central hypersomnias

PubMed Central

Susta, Marek

2012-01-01

Central hypersomnias are diseases manifested in excessive daytime sleepiness (EDS) not caused by disturbed nocturnal sleep or misaligned circadian rhythms. Central hypersomnias includes narcolepsy with and without cataplexy, recurrent hypersomnia, idiopathic hypersomnia, with and without long sleep time, behaviorally induced insufficient sleep syndrome, hypersomnia and narcolepsy due to medical conditions, and finally hypersomnia induced by substance intake. The Epworth Sleepiness Scale is a subjective tool mostly used for EDS assessment, while the Multiple Sleep Latency Test serves as an objective diagnostic method for narcolepsy and idiopathic hypersomnias. As for symptomatic therapy of EDS, the central nervous system stimulants modafinil and methylphenidate seem to work well in most cases and in narcolepsy and Parkinson’s disease; sodium oxybate also has notable therapeutic value. PMID:22973425

Disturbed sleep in attention-deficit hyperactivity disorder (ADHD) is not a question of psychiatric comorbidity or ADHD presentation.

PubMed

Virring, Anne; Lambek, Rikke; Thomsen, Per H; Møller, Lene R; Jennum, Poul J

2016-06-01

Attention-deficit hyperactivity disorder (ADHD) is a heterogeneous psychiatric disorder with three different presentations and high levels of psychiatric comorbidity. Serious sleep complaints are also common, but the role of the presentations and comorbidity in sleep is under-investigated in ADHD. Consequently, the goal of the study was to investigate sleep problems in medicine-naive school-aged children (mean age = 9.6 years) with ADHD compared to controls using objective methods and to examine the role of comorbidity and presentations. Ambulatory polysomnography results suggested that children with ADHD (n = 76) had significantly more sleep disturbances than controls (n = 25), including a larger percentage of rapid eye movement (REM) sleep and more sleep cycles, as well as lower mean sleep efficiency, mean non-REM (NREM) sleep stage 1 and mean NREM sleep stage 3. No significant between-group differences were found on the multiple sleep latency test. Stratifying for comorbidity in the ADHD group did not reveal major differences between groups, but mean sleep latency was significantly longer in children with ADHD and no comorbidity compared to controls (36.1 min; SD = 30.1 versus 22.6 min; SD = 15.2). No differences were found between ADHD presentations. Our results support the presence of night-time sleep disturbances in children with ADHD. Poor sleep does not appear to be attributable to comorbidity alone, nor do sleep disturbances differ within ADHD presentations. © 2016 European Sleep Research Society.

The Effects of Sleep Problems on the Trajectory of Antisocial Behavior from Adolescence through Early Adulthood in Taiwan: Family Functioning as a Moderator.

PubMed

Chang, Ling-Yin; Wu, Chi-Chen; Lin, Linen Nymphas; Yen, Lee-Lan; Chang, Hsing-Yi

2016-07-01

To examine the longitudinal relationship between sleep problems and development of antisocial behavior from adolescence through young adulthood, and to investigate whether family functioning moderates the association being examined. Potential sex differences were also explored. A total of 2,491 adolescents participated in a prospective study spanning 2009 through 2014 in northern Taiwan. Measures included sleep problems, family functioning (parental support, family interaction, and family conflict), antisocial behavior, and other individual characteristics (sex, age, parental education, family economic stress, depressive symptoms, and stressful life events). Random coefficient growth models were used to test study hypotheses. Sleep problems were significantly and positively associated with antisocial behavior (B = 0.088 and 0.038 for males and females, respectively). Sex differences further emerged in the moderating effects of family functioning. Among males, those with high family interaction had a weaker association between sleep problems and antisocial behavior; among females, the examined association was weaker in those with high parental support. For both sexes, the association between sleep problems and antisocial behavior was stronger for those with high family conflict. Our findings highlight the robust link between sleep problems and adolescent antisocial behavior over time. We also show for the first time that the association depends on family functioning. Prevention methods and treatment of sleep problems in youths that incorporate family functioning may yield significant benefits for decreasing antisocial behavior. Sex-specific intervention and prevention approaches should also be considered. © 2016 Associated Professional Sleep Societies, LLC.

Automated selective disruption of slow wave sleep

PubMed Central

Ooms, Sharon J.; Zempel, John M.; Holtzman, David M.; Ju, Yo-El S.

2017-01-01

Background Slow wave sleep (SWS) plays an important role in neurophysiologic restoration. Experimentally testing the effect of SWS disruption previously required highly time-intensive and subjective methods. Our goal was to develop an automated and objective protocol to reduce SWS without affecting sleep architecture. New Method We developed a custom Matlab™ protocol to calculate electroencephalogram spectral power every 10 seconds live during a polysomnogram, exclude artifact, and, if measurements met criteria for SWS, deliver increasingly louder tones through earphones. Middle-aged healthy volunteers (n=10) each underwent 2 polysomnograms, one with the SWS disruption protocol and one with sham condition. Results The SWS disruption protocol reduced SWS compared to sham condition, as measured by spectral power in the delta (0.5–4 Hz) band, particularly in the 0.5–2 Hz range (mean 20% decrease). A compensatory increase in the proportion of total spectral power in the theta (4–8 Hz) and alpha (8–12 Hz) bands was seen, but otherwise normal sleep features were preserved. N3 sleep decreased from 20±34 to 3±6 minutes, otherwise there were no significant changes in total sleep time, sleep efficiency, or other macrostructural sleep characteristics. Comparison with existing method This novel SWS disruption protocol produces specific reductions in delta band power similar to existing methods, but has the advantage of being automated, such that SWS disruption can be performed easily in a highly standardized and operator-independent manner. Conclusion This automated SWS disruption protocol effectively reduces SWS without impacting overall sleep architecture. PMID:28238859

Modulating influences of memory strength and sensitivity of the retrieval test on the detectability of the sleep consolidation effect.

PubMed

Schoch, Sarah F; Cordi, Maren J; Rasch, Björn

2017-11-01

Emotionality can increase recall probability of memories as emotional information is highly relevant for future adaptive behavior. It has been proposed that memory processes acting during sleep selectively promote the consolidation of emotional memories, so that neutral memories no longer profit from sleep consolidation after learning. This appears as a selective effect of sleep for emotional memories. However, other factors contribute to the appearance of a consolidation benefit and influence this interpretation. Here we show that the strength of the memory trace before sleep and the sensitivity of the retrieval test after sleep are critical factors contributing to the detection of the benefit of sleep on memory for emotional and neutral stimuli. 228 subjects learned emotional and neutral pictures and completed a free recall after a 12-h retention interval of either sleep or wakefulness. We manipulated memory strength by including an immediate retrieval test before the retention interval in half of the participants. In addition, we varied the sensitivity of the retrieval test by including an interference learning task before retrieval testing in half of the participants. We show that a "selective" benefit of sleep for emotional memories only occurs in the condition with high memory strength. Furthermore, this "selective" benefit disappeared when we controlled for the memory strength before the retention interval and used a highly sensitive retrieval test. Our results indicate that although sleep benefits are more robust for emotional memories, neutral memories similarly profit from sleep after learning when more sensitive indicators are used. We conclude that whether sleep benefits on memory appear depends on several factors, including emotion, memory strength and sensitivity of the retrieval test. Copyright © 2017 Elsevier Inc. All rights reserved.

The Effects of Sleep Problems on the Trajectory of Antisocial Behavior from Adolescence through Early Adulthood in Taiwan: Family Functioning as a Moderator

PubMed Central

Chang, Ling-Yin; Wu, Chi-Chen; Lin, Linen Nymphas; Yen, Lee-Lan; Chang, Hsing-Yi

2016-01-01

Study Objectives: To examine the longitudinal relationship between sleep problems and development of antisocial behavior from adolescence through young adulthood, and to investigate whether family functioning moderates the association being examined. Potential sex differences were also explored. Methods: A total of 2,491 adolescents participated in a prospective study spanning 2009 through 2014 in northern Taiwan. Measures included sleep problems, family functioning (parental support, family interaction, and family conflict), antisocial behavior, and other individual characteristics (sex, age, parental education, family economic stress, depressive symptoms, and stressful life events). Random coefficient growth models were used to test study hypotheses. Results: Sleep problems were significantly and positively associated with antisocial behavior (B = 0.088 and 0.038 for males and females, respectively). Sex differences further emerged in the moderating effects of family functioning. Among males, those with high family interaction had a weaker association between sleep problems and antisocial behavior; among females, the examined association was weaker in those with high parental support. For both sexes, the association between sleep problems and antisocial behavior was stronger for those with high family conflict. Conclusions: Our findings highlight the robust link between sleep problems and adolescent antisocial behavior over time. We also show for the first time that the association depends on family functioning. Prevention methods and treatment of sleep problems in youths that incorporate family functioning may yield significant benefits for decreasing antisocial behavior. Sex-specific intervention and prevention approaches should also be considered. Citation: Chang LY, Wu CC, Lin LN, Yen LL, Chang HY. The effects of sleep problems on the trajectory of antisocial behavior from adolescence through early adulthood in Taiwan: family functioning as a moderator. SLEEP 2016;39(7):1441–1449. PMID:27166239

TNFα G308A polymorphism is associated with resilience to sleep deprivation-induced psychomotor vigilance performance impairment in healthy young adults.

PubMed

Satterfield, Brieann C; Wisor, Jonathan P; Field, Stephanie A; Schmidt, Michelle A; Van Dongen, Hans P A

2015-07-01

Cytokines such as TNFα play an integral role in sleep/wake regulation and have recently been hypothesized to be involved in cognitive impairment due to sleep deprivation. We examined the effect of a guanine to adenine substitution at position 308 in the TNFα gene (TNFα G308A) on psychomotor vigilance performance impairment during total sleep deprivation. A total of 88 healthy women and men (ages 22-40) participated in one of five laboratory total sleep deprivation experiments. Performance on a psychomotor vigilance test (PVT) was measured every 2-3h. The TNFα 308A allele, which is less common than the 308G allele, was associated with greater resilience to psychomotor vigilance performance impairment during total sleep deprivation (regardless of time of day), and also provided a small performance benefit at baseline. The effect of genotype on resilience persisted when controlling for between-subjects differences in age, gender, race/ethnicity, and baseline sleep duration. The TNFα G308A polymorphism predicted less than 10% of the overall between-subjects variance in performance impairment during sleep deprivation. Nonetheless, the differential effect of the polymorphism at the peak of performance impairment was more than 50% of median performance impairment at that time, which is sizeable compared to the effects of other genotypes reported in the literature. Our findings provided evidence for a role of TNFα in the effects of sleep deprivation on psychomotor vigilance performance. Furthermore, the TNFα G308A polymorphism may have predictive potential in a biomarker panel for the assessment of resilience to psychomotor vigilance performance impairment due to sleep deprivation. Copyright © 2014 Elsevier Inc. All rights reserved.

The effects of sleep deprivation on item and associative recognition memory.

PubMed

Ratcliff, Roger; Van Dongen, Hans P A

2018-02-01

Sleep deprivation adversely affects the ability to perform cognitive tasks, but theories range from predicting an overall decline in cognitive functioning because of reduced stability in attentional networks to specific deficits in various cognitive domains or processes. We measured the effects of sleep deprivation on two memory tasks, item recognition ("was this word in the list studied") and associative recognition ("were these two words studied in the same pair"). These tasks test memory for information encoded a few minutes earlier and so do not address effects of sleep deprivation on working memory or consolidation after sleep. A diffusion model was used to decompose accuracy and response time distributions to produce parameter estimates of components of cognitive processing. The model assumes that over time, noisy evidence from the task stimulus is accumulated to one of two decision criteria, and parameters governing this process are extracted and interpreted in terms of distinct cognitive processes. Results showed that sleep deprivation reduces drift rate (evidence used in the decision process), with little effect on the other components of the decision process. These results contrast with the effects of aging, which show little decline in item recognition but large declines in associative recognition. The results suggest that sleep deprivation degrades the quality of information stored in memory and that this may occur through degraded attentional processes. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Diagnostic accuracy of level 3 portable sleep tests versus level 1 polysomnography for sleep-disordered breathing: a systematic review and meta-analysis

PubMed Central

El Shayeb, Mohamed; Topfer, Leigh-Ann; Stafinski, Tania; Pawluk, Lawrence; Menon, Devidas

2014-01-01

Background: Greater awareness of sleep-disordered breathing and rising obesity rates have fueled demand for sleep studies. Sleep testing using level 3 portable devices may expedite diagnosis and reduce the costs associated with level 1 in-laboratory polysomnography. We sought to assess the diagnostic accuracy of level 3 testing compared with level 1 testing and to identify the appropriate patient population for each test. Methods: We conducted a systematic review and meta-analysis of comparative studies of level 3 versus level 1 sleep tests in adults with suspected sleep-disordered breathing. We searched 3 research databases and grey literature sources for studies that reported on diagnostic accuracy parameters or disease management after diagnosis. Two reviewers screened the search results, selected potentially relevant studies and extracted data. We used a bivariate mixed-effects binary regression model to estimate summary diagnostic accuracy parameters. Results: We included 59 studies involving a total of 5026 evaluable patients (mostly patients suspected of having obstructive sleep apnea). Of these, 19 studies were included in the meta-analysis. The estimated area under the receiver operating characteristics curve was high, ranging between 0.85 and 0.99 across different levels of disease severity. Summary sensitivity ranged between 0.79 and 0.97, and summary specificity ranged between 0.60 and 0.93 across different apnea–hypopnea cut-offs. We saw no significant difference in the clinical management parameters between patients who underwent either test to receive their diagnosis. Interpretation: Level 3 portable devices showed good diagnostic performance compared with level 1 sleep tests in adult patients with a high pretest probability of moderate to severe obstructive sleep apnea and no unstable comorbidities. For patients suspected of having other types of sleep-disordered breathing or sleep disorders not related to breathing, level 1 testing remains the reference standard. PMID:24218531

Light as a chronobiologic countermeasure for long-duration space operations

NASA Technical Reports Server (NTRS)

Samel, Alexander (Editor); Gander, Philippa (Editor); Evans, Julie; Graeber, R. Curtis; Hackett, Elizabeth; Keil, Lanny; Maab, Hartmut; Raabe, Wolfgang; Rosekind, Mark; Rountree, Mike

1991-01-01

Long-duration space missions require adaptation to work-rest schedules which are substantially shifted with respect to earth. Astronauts are expected to work in two-shift operations and the environmental synchronizers (zeitgebers) in a spacecraft differ significantly from those on earth. A study on circadian rhythms, sleep, and performance was conducted by exposing four subjects to 6 deg head-down tilt bedrest (to simulate the effects of the weightless condition) and imposing a 12-h shift (6 h delay per day for two days). Bright light was tested in a cross-over design as a countermeasure for achieving faster resynchronization and regaining stable conditions for sleep and circadian rhythmicity. Data collection included objective sleep recording, temperature, heart rate, and excretion of hormones and electrolytes as well as performance and responses to questionnaires. Even without a shift in the sleep-wake cycle, the sleep quantity, circadian amplitudes and 24 h means decreased in many functions under bedrest conditions. During the shift days, sleepiness and fatigue increased, and alertness decreased. However, sleep quantity was regained, and resynchronization was completed within seven days after the shift for almost all functions, irrespective of whether light was administered during day-time or night-time hours. The time of day of light exposure surprisingly appeared not to have a discriminatory effect on the resynchronization speed under shift and bedrest conditions. The results indicate that simulated weightlessness alters circadian rhythms and sleep, and that schedule changes induce additional physiological disruption with decreased subjective alertness and increased fatigue. Because of their operational implications, these phenomena deserve additional investigation.

The effect of memantine on sleep architecture and psychiatric symptoms in patients with Alzheimer's disease.

PubMed

Ishikawa, Ichiro; Shinno, Hideto; Ando, Nobuo; Mori, Takahiro; Nakamura, Yu

2016-06-01

Behavioural and psychological symptoms of dementia (BPSD) are commonly present in patients with Alzheimer's disease (AD). Disturbed sleep quality is also observed in AD patients. However, the effects of memantine on sleep architecture have not been investigated. The purpose of this study was to investigate the effects of memantine on polysomnography (PSG) variables and BPSD. In total, 12 patients with AD (mean age: 79.0±4.1 years old) were enrolled in this study. The following tests were performed: the Neuropsychiatric Inventory for the assessment of BPSD, the Mini-Mental State Examination (MMSE) for cognitive function, and PSG for evaluation of sleep architecture. After baseline examinations, patients were treated with memantine according to a standard prescription protocol. After being treated with 20 mg/day of memantine for 4 weeks, examinations were carried out again. All subjects completed the trial. The mean MMSE and NPI scores were 22.6±3.4 and 13.8±12.9, respectively. Treatment with memantine significantly decreased the NPI score (5.8±4.3, p<0.01). There were significant decreases in the scores of subscales for anxiety (p=0.04) and irritability/lability (p=0.04). PSG demonstrated a longer total sleep time (TST) (p<0.01), increases in sleep efficiency (p<0.01) and time spent in stage II (% TST, p=0.02), and decreases in nocturnal awakening (p<0.01), the periodic limb movement index (p<0.01), and time spent in stage I (% TST, p=0.02). Memantine was effective for reducing fragmented sleep and improving BPSD, and was well tolerated.

Early to bed, early to rise! Sleep habits and academic performance in college students.

PubMed

Eliasson, Arne H; Lettieri, Christopher J; Eliasson, Arn H

2010-02-01

Prior studies have placed emphasis on the need for adequate total sleep time for student performance. We sought to investigate the relative importance of total sleep time compared to the timing of sleep and wakefulness for academic performance. We performed a questionnaire-based survey of college students in October 2007. The questionnaire gathered detailed information on sleep habits including naps, reasons for missing sleep, academic performance, study habits, time spent working outside of school, and stimulant use. Compared to those with the lowest academic performance, students with the highest performance had significantly earlier bedtimes (p = 0.05) and wake times (p = 0.008). Napping tended to be more common among high performers (p = 0.07). Of importance, there were no significant differences in total sleep time with or without naps, weekend sleep habits, study time, gender, race, reasons for staying up at night, nor in use of caffeinated beverages, over-the-counter stimulant pills, or use of prescription stimulants. Timing of sleep and wakefulness correlated more closely with academic performance than total sleep time and other relevant factors. These findings have important implications for programs intended to improve academic performance by targeting sleep habits of students.

Plasticity of the Intrinsic Period of the Human Circadian Timing System

PubMed Central

Scheer, Frank A.J.L.; Wright, Kenneth P.; Kronauer, Richard E.; Czeisler, Charles A.

2007-01-01

Human expeditions to Mars will require adaptation to the 24.65-h Martian solar day-night cycle (sol), which is outside the range of entrainment of the human circadian pacemaker under lighting intensities to which astronauts are typically exposed. Failure to entrain the circadian time-keeping system to the desired rest-activity cycle disturbs sleep and impairs cognitive function. Furthermore, differences between the intrinsic circadian period and Earth's 24-h light-dark cycle underlie human circadian rhythm sleep disorders, such as advanced sleep phase disorder and non-24-hour sleep-wake disorders. Therefore, first, we tested whether exposure to a model-based lighting regimen would entrain the human circadian pacemaker at a normal phase angle to the 24.65-h Martian sol and to the 23.5-h day length often required of astronauts during short duration space exploration. Second, we tested here whether such prior entrainment to non-24-h light-dark cycles would lead to subsequent modification of the intrinsic period of the human circadian timing system. Here we show that exposure to moderately bright light (∼450 lux; ∼1.2 W/m2) for the second or first half of the scheduled wake episode is effective for entraining individuals to the 24.65-h Martian sol and a 23.5-h day length, respectively. Estimations of the circadian periods of plasma melatonin, plasma cortisol, and core body temperature rhythms collected under forced desynchrony protocols revealed that the intrinsic circadian period of the human circadian pacemaker was significantly longer following entrainment to the Martian sol as compared to following entrainment to the 23.5-h day. The latter finding of after-effects of entrainment reveals for the first time plasticity of the period of the human circadian timing system. Both findings have important implications for the treatment of circadian rhythm sleep disorders and human space exploration. PMID:17684566

Sensitivity to ethanol hypnosis and modulation of chloride channels does not cosegregate with pentobarbital sensitivity in HS mice.

PubMed

Allan, A M; Harris, R A

1989-06-01

Several findings suggest that barbiturates and alcohol produce their sedative effects through a common neural and possibly a common genetic mechanism. We tested this hypothesis by examining the correlation between ethanol and pentobarbital sedative effects in individual animals from a genetically heterogeneous population. The duration of pentobarbital-induced hypnosis (sleep-time) was unrelated to the sleep-time produced by ethanol in heterogeneous stock (HS) mice. Therefore, the present study also examined the effect of ethanol, pentobarbital, and flunitrazepam on muscimol-stimulated chloride flux into brain membranes prepared from HS mice selected for differences in pentobarbital- and ethanol-induced sleep-time. Brain membranes from mice selected for differences in ethanol sleep-time were differentially responsive to ethanol- and flunitrazepam-, but not to pentobarbital-induced augmentation of muscimol-stimulated chloride flux. No differences in augmentation of chloride flux by ethanol, pentobarbital, or flunitrazepam were found in membranes prepared from mice differentially sensitive to pentobarbital hypnosis. The ability of muscimol to stimulate chloride uptake was not related to ethanol or pentobarbital sensitivity. These findings suggest that sensitivity to ethanol is not likely to be genetically linked to pentobarbital sensitivity.

The impact of prolonged violent video-gaming on adolescent sleep: an experimental study.

PubMed

King, Daniel L; Gradisar, Michael; Drummond, Aaron; Lovato, Nicole; Wessel, Jason; Micic, Gorica; Douglas, Paul; Delfabbro, Paul

2013-04-01

Video-gaming is an increasingly prevalent activity among children and adolescents that is known to influence several areas of emotional, cognitive and behavioural functioning. Currently there is insufficient experimental evidence about how extended video-game play may affect adolescents' sleep. The aim of this study was to investigate the short-term impact of adolescents' prolonged exposure to violent video-gaming on sleep. Seventeen male adolescents (mean age = 16 ± 1 years) with no current sleep difficulties played a novel, fast-paced, violent video-game (50 or 150 min) before their usual bedtime on two different testing nights in a sleep laboratory. Objective (polysomnography-measured sleep and heart rate) and subjective (single-night sleep diary) measures were obtained to assess the arousing effects of prolonged gaming. Compared with regular gaming, prolonged gaming produced decreases in objective sleep efficiency (by 7 ± 2%, falling below 85%) and total sleep time (by 27 ± 12 min) that was contributed by a near-moderate reduction in rapid eye movement sleep (Cohen's d = 0.48). Subjective sleep-onset latency significantly increased by 17 ± 8 min, and there was a moderate reduction in self-reported sleep quality after prolonged gaming (Cohen's d = 0.53). Heart rate did not differ significantly between video-gaming conditions during pre-sleep game-play or the sleep-onset phase. Results provide evidence that prolonged video-gaming may cause clinically significant disruption to adolescent sleep, even when sleep after video-gaming is initiated at normal bedtime. However, physiological arousal may not necessarily be the mechanism by which technology use affects sleep. © 2012 European Sleep Research Society.

Sleep Dependent Memory Consolidation in Children with Autism Spectrum Disorder

PubMed Central

Maski, Kiran; Holbrook, Hannah; Manoach, Dara; Hanson, Ellen; Kapur, Kush; Stickgold, Robert

2015-01-01

Study Objectives: Examine the role of sleep in the consolidation of declarative memory in children with autism spectrum disorder (ASD). Design: Case-control study. Setting: Home-based study with sleep and wake conditions. Participants: Twenty-two participants with ASD and 20 control participants between 9 and 16 y of age. Measurements and Results: Participants were trained to criterion on a spatial declarative memory task and then given a cued recall test. Retest occurred after a period of daytime wake (Wake) or a night of sleep (Sleep) with home-based polysomnography; Wake and Sleep conditions were counterbalanced. Children with ASD had poorer sleep efficiency than controls, but other sleep macroarchitectural and microarchitectural measures were comparable after controlling for age and medication use. Both groups demonstrated better memory consolidation across Sleep than Wake, although participants with ASD had poorer overall memory consolidation than controls. There was no interaction between group and condition. The change in performance across sleep, independent of medication and age, showed no significant relationships with any specific sleep parameters other than total sleep time and showed a trend toward less forgetting in the control group. Conclusion: This study shows that despite their more disturbed sleep quality, children with autism spectrum disorder (ASD) still demonstrate more stable memory consolidation across sleep than in wake conditions. The findings support the importance of sleep for stabilizing memory in children with and without neurodevelopmental disabilities. Our results suggest that improving sleep quality in children with ASD could have direct benefits to improving their overall cognitive functioning. Citation: Maski K, Holbrook H, Manoach D, Hanson E, Kapur K, Stickgold R. Sleep dependent memory consolidation in children with autism spectrum disorder. SLEEP 2015;38(12):1955–1963. PMID:26194566

[Effects of chronic partial sleep deprivation on growth and learning/memory in young rats].

PubMed

Jiang, Fan; Shen, Xiao-Ming; Li, Sheng-Hui; Cui, Mao-Long; Zhang, Yin; Wang, Cheng; Yu, Xiao-Gang; Yan, Chong-Huai

2009-02-01

The effects of sleep deprivation on the immature brain remain unknown. Based on a computer controlled chronic sleep deprivation animal model, the effects of chronic partial sleep deprivation on growth, learning and memory in young rats were explored. Twelve weaned male Spraque-Dawley rats (3-week-old) were randomly divided into sleep deprivation, test control and blank control groups. Sleep deprivation was performed using computer-controlled "disc-over-water" technique at 8-11 am daily, for 14 days. The temperature and weights were measured every 7 days. Morris water maze was used to test spatial learning and memory abilities before and 7 and 14 days after sleep deprivation. After 14 days of sleep deprivation, the rats were sacrificed for weighting their major organs. After 14 days of sleep deprivation, the rats' temperature increased significantly. During the sleep deprivation, the rate of weight gain in the sleep deprivation group was much slower than that in the test control and blank control groups. The thymus of the rats subjected to sleep deprivation was much lighter than that of the blank control group. After 7 days of sleep deprivation, the rats showed slower acquisition of reference memory, but were capable of successfully performing the task by repeated exposure to the test. Such impairment of reference memory was not seen 14 days after sleep deprivation. Chronic sleep deprivation can affect growth of immature rats, as well as their abilities to acquire spatial reference memory.

Sleep Perception and Misperception in Chronic Cocaine Users During Abstinence.

PubMed

Hodges, Sarah E; Pittman, Brian; Morgan, Peter T

2017-03-01

During abstinence, chronic cocaine users experience an objective worsening of sleep that is perceived as qualitatively improving. This phenomenon has been termed "occult insomnia." The objective of this study was to determine whether chronic cocaine users experience positive sleep state misperception during abstinence. Forty-three cocaine-dependent persons were admitted to an inpatient research facility for 12 days and 11 nights to participate in a treatment study of modafinil. Polysomnographic sleep recordings were performed on study nights 3, 4, 10, and 11, when participants were on average 1 and 2 weeks abstinent from cocaine. Participants also completed sleep diary questionnaires every evening before bed and every morning upon awakening. Polysomnographic and sleep diary measurements of total sleep time, sleep latency, time awake after sleep onset, and time in bed after final awakening were compared. Chronic cocaine users accurately reported total sleep time after 1 week of abstinence but overreported total sleep time by an average of 40 min after 2 weeks of abstinence. Underestimating sleep latency and time spent awake after sleep onset were responsible for this difference. Positive sleep state misperception is revealed in chronic cocaine users after 2 weeks of abstinence and is consistent with the previously identified "occult insomnia" in this population. © Sleep Research Society 2016. Published by Oxford University Press on behalf of the Sleep Research Society. All rights reserved. For permissions, please e-mail journals.permissions@oup.com.

Cholinergic Oculomotor Nucleus Activity Is Induced by REM Sleep Deprivation Negatively Impacting on Cognition.

PubMed

Santos, Patrícia Dos; Targa, Adriano D S; Noseda, Ana Carolina D; Rodrigues, Lais S; Fagotti, Juliane; Lima, Marcelo M S

2017-09-01

Several efforts have been made to understand the involvement of rapid eye movement (REM) sleep for cognitive processes. Consolidation or retention of recognition memories is severely disrupted by REM sleep deprivation (REMSD). In this regard, pedunculopontine tegmental nucleus (PPT) and other brainstem nuclei, such as pontine nucleus (Pn) and oculomotor nucleus (OCM), appear to be candidates to take part in this REM sleep circuitry with potential involvement in cognition. Therefore, the objective of this study was to investigate a possible association between the performance of Wistar rats in a declarative memory and PPT, Pn, and OCM activities after different periods of REMSD. We examined c-Fos and choline acetyltransferase (ChaT) expressions as indicators of neuronal activity as well as a familiarity-based memory test. The animals were distributed in groups: control, REMSD, and sleep rebound (REB). At the end of the different REMSD (24, 48, 72, and 96 h) and REB (24 h) time points, the rats were immediately tested in the object recognition test and then the brains were collected. Results indicated that OCM neurons presented an increased activity, due to ChaT-labeling associated with REMSD that negatively correlated (r = -0.32) with the cognitive performance. This suggests the existence of a cholinergic compensatory mechanism within the OCM during REMSD. We also showed that 24 h of REMSD impacted similarly in memory, compared to longer periods of REMSD. These data extend the notion that REM sleep is influenced by areas other than PPT, i.e., Pn and OCM, which could be key players in both sleep processes and cognition.

Acute Kynurenine Challenge Disrupts Sleep-Wake Architecture and Impairs Contextual Memory in Adult Rats.

PubMed

Pocivavsek, Ana; Baratta, Annalisa M; Mong, Jessica A; Viechweg, Shaun S

2017-11-01

Tryptophan metabolism via the kynurenine pathway may represent a key molecular link between sleep loss and cognitive dysfunction. Modest increases in the kynurenine pathway metabolite kynurenic acid (KYNA), which acts as an antagonist at N-methyl-d-aspartate and α7 nicotinic acetylcholine receptors in the brain, result in cognitive impairments. As glutamatergic and cholinergic neurotransmissions are critically involved in modulation of sleep, our current experiments tested the hypothesis that elevated KYNA adversely impacts sleep quality. Adult male Wistar rats were treated with vehicle (saline) and kynurenine (25, 50, 100, and 250 mg/kg), the direct bioprecursor of KYNA, intraperitoneally at zeitgeber time (ZT) 0 to rapidly increase brain KYNA. Levels of KYNA in the brainstem, cortex, and hippocampus were determined at ZT 0, ZT 2, and ZT 4, respectively. Analyses of vigilance state-related parameters categorized as wake, rapid eye movement (REM), and non-REM (NREM) as well as spectra power analysis during NREM and REM were assessed during the light phase. Separate animals were tested in the passive avoidance paradigm, testing contextual memory. When KYNA levels were elevated in the brain, total REM duration was reduced and total wake duration was increased. REM and wake architecture, assessed as number of vigilance state bouts and average duration of each bout, and theta power during REM were significantly impacted. Kynurenine challenge impaired performance in the hippocampal-dependent contextual memory task. Our results introduce kynurenine pathway metabolism and formation of KYNA as a novel molecular target contributing to sleep disruptions and cognitive impairments. © Sleep Research Society 2017. Published by Oxford University Press on behalf of the Sleep Research Society. All rights reserved. For permissions, please e-mail journals.permissions@oup.com.