Time perception, pacing and exercise intensity: maximal exercise distorts the perception of time.

PubMed

Edwards, A M; McCormick, A

2017-10-15

Currently there are no data examining the impact of exercise on the perception of time, which is surprising as optimal competitive performance is dependent on accurate pacing using knowledge of time elapsed. With institutional ethics approval, 12 recreationally active adult participants (f=7, m=5) undertook both 30s Wingate cycles and 20min (1200s) rowing ergometer bouts as short and long duration self-paced exercise trials, in each of three conditions on separate occasions: 1) light exertion: RPE 11, 2) heavy exertion: RPE 15, 3) maximal exertion: RPE 20. Participants were unaware of exercise duration and were required to verbally indicate when they perceived (subjective time) 1) 25%, 2) 50%, 3) 75% and 4) 100% of each bout's measured (chronological) time had elapsed. In response to the Wingate task, there was no difference between durations of subjective time at the 25%, nor at the 50% interval. However, at the 75% and 100% intervals, the estimate for the RPE 20 condition was shortest (P<0.01). In response to rowing, there were no differences at the 25% interval, but there was some evidence that the RPE 20 condition was perceived shorter at 50%. At 75% and 100%, the RPE 20 condition was perceived to be shorter than both RPE 15 (P=0.04) and RPE 11 (P=0.008) conditions. This study is the first to empirically demonstrate that exercise intensity distorts time perception, particularly during maximal exercise. Consequently external feedback of chronological time may be an important factor for athletes undertaking maximal effort tasks or competitions. Copyright © 2017 Elsevier Inc. All rights reserved.

Dissociations and interactions between time, numerosity and space processing

PubMed Central

Cappelletti, Marinella; Freeman, Elliot D.; Cipolotti, Lisa

2009-01-01

This study investigated time, numerosity and space processing in a patient (CB) with a right hemisphere lesion. We tested whether these magnitude dimensions share a common magnitude system or whether they are processed by dimension-specific magnitude systems. Five experimental tasks were used: Tasks 1–3 assessed time and numerosity independently and time and numerosity jointly. Tasks 4 and 5 investigated space processing independently and space and numbers jointly. Patient CB was impaired at estimating time and at discriminating between temporal intervals, his errors being underestimations. In contrast, his ability to process numbers and space was normal. A unidirectional interaction between numbers and time was found in both the patient and the control subjects. Strikingly, small numbers were perceived as lasting shorter and large numbers as lasting longer. In contrast, number processing was not affected by time, i.e. short durations did not result in perceiving fewer numbers and long durations in perceiving more numbers. Numbers and space also interacted, with small numbers answered faster when presented on the left side of space, and the reverse for large numbers. Our results demonstrate that time processing can be selectively impaired. This suggests that mechanisms specific for time processing may be partially independent from those involved in processing numbers and space. However, the interaction between numbers and time and between numbers and space also suggests that although independent, there maybe some overlap between time, numbers and space. These data suggest a partly shared mechanism between time, numbers and space which may be involved in magnitude processing or may be recruited to perform cognitive operations on magnitude dimensions. PMID:19501604

Discrimination of phoneme length differences in word and sentence contexts

NASA Astrophysics Data System (ADS)

Kawai, Norimune; Carrell, Thomas

2005-09-01

The ability of listeners to discriminate phoneme duration differences within word and sentence contexts was measured. This investigation was part of a series of studies examining the audibility and perceptual importance of speech modifications produced by stuttering intervention techniques. Just noticeable differences (jnd's) of phoneme lengths were measured via the parameter estimation by sequential testing (PEST) task, an adaptive tracking procedure. The target phonemes were digitally manipulated to vary from normal (130 m) to prolonged (210 m) duration in 2-m increments. In the first condition the phonemes were embedded in words. In the second condition the phonemes were embedded within words, which were further embedded in sentences. A four-interval forced-choice (4IAX) task was employed on each trial, and the PEST procedure determined the duration at which each listener correctly detected a difference between the normal duration and the test duration 71% of the time. The results revealed that listeners were able to reliably discriminate approximately 15-m differences in word context and 10-m differences in sentence context. An independent t-test showed a difference in discriminability between word and sentence contexts to be significant. These results indicate that duration differences were better perceived within a sentence context.

Gaze Following in Children with Autism: Do High Interest Objects Boost Performance?

ERIC Educational Resources Information Center

Thorup, Emilia; Kleberg, Johan Lundin; Falck-Ytter, Terje

2017-01-01

This study tested whether including objects perceived as highly interesting by children with autism during a gaze following task would result in increased first fixation durations on the target objects. It has previously been found that autistic children differentiate less between an object another person attends to and unattended objects in terms…

Quantification of lower extremity physical exposures in various combinations of sit/stand time duration associated with sit-stand workstation.

PubMed

Pei, Huining; Yu, Suihuai; Babski-Reeves, Kari; Chu, Jianjie; Qu, Min; Tian, Baozhen; Li, Wenhua

2017-05-16

Sit-stand workstations are available for office work purposes but there is a dearth of quantitative evidence to state benefits for lower limb outcomes while using them. And there are no guidelines on what constitutes appropriate sit/stand time duration. The primary aim of this study has been to compare muscle activity and perceived discomfort in the lower extremity during various combinations of sit/stand time duration associated with a sit-stand workstation separately and to evaluate the effects of the sit-stand workstation on the lower extremity during the text entry task. During the 5 days, all participants completed a 2-h text entry task each day for various sit/stand time duration combinations as follows: 5/25 min, 10/20 min, 15/15 min, 20/10 min, 25/5 min. Lower extremity muscular exposure of 12 male and 13 female participants was collected at 8 sites by surface electromyography and body discomfort was calculated by a questionnaire under those 5 conditions. Results have demonstrated that lower extremity muscle activity has been significantly varied among the 5 sit/stand time duration groups. Perceived level of discomfort (PLD) has not differed significantly for 9 out of 10 body parts. The muscle activity of the thigh region was influenced by sit/stand time duration significantly. Ergonomic exposures of lower extremity when using a sit-stand workstation were increased, particularly during the long time standing posture. Results indicate that body mass index (BMI) and gender were not significant factors in this study. Combination of sit/stand time duration 25/5 min appears to show positive effects on relief of muscle exposure of back of thigh in the shifts of sitting and standing work position. Med Pr 2017;68(3):315-327. This work is available in Open Access model and licensed under a CC BY-NC 3.0 PL license.

Expansion and Compression of Time Correlate with Information Processing in an Enumeration Task.

PubMed

Wutz, Andreas; Shukla, Anuj; Bapi, Raju S; Melcher, David

2015-01-01

Perception of temporal duration is subjective and is influenced by factors such as attention and context. For example, unexpected or emotional events are often experienced as if time subjectively expands, suggesting that the amount of information processed in a unit of time can be increased. Time dilation effects have been measured with an oddball paradigm in which an infrequent stimulus is perceived to last longer than standard stimuli in the rest of the sequence. Likewise, time compression for the oddball occurs when the duration of the standard items is relatively brief. Here, we investigated whether the amount of information processing changes when time is perceived as distorted. On each trial, an oddball stimulus of varying numerosity (1-14 items) and duration was presented along with standard items that were either short (70 ms) or long (1050 ms). Observers were instructed to count the number of dots within the oddball stimulus and to judge its relative duration with respect to the standards on that trial. Consistent with previous results, oddballs were reliably perceived as temporally distorted: expanded for longer standard stimuli blocks and compressed for shorter standards. The occurrence of these distortions of time perception correlated with perceptual processing; i.e. enumeration accuracy increased when time was perceived as expanded and decreased with temporal compression. These results suggest that subjective time distortions are not epiphenomenal, but reflect real changes in sensory processing. Such short-term plasticity in information processing rate could be evolutionarily advantageous in optimizing perception and action during critical moments.

Accumulation of Inertial Sensory Information in the Perception of Whole Body Yaw Rotation.

PubMed

Nesti, Alessandro; de Winkel, Ksander; Bülthoff, Heinrich H

2017-01-01

While moving through the environment, our central nervous system accumulates sensory information over time to provide an estimate of our self-motion, allowing for completing crucial tasks such as maintaining balance. However, little is known on how the duration of the motion stimuli influences our performances in a self-motion discrimination task. Here we study the human ability to discriminate intensities of sinusoidal (0.5 Hz) self-rotations around the vertical axis (yaw) for four different stimulus durations (1, 2, 3 and 5 s) in darkness. In a typical trial, participants experienced two consecutive rotations of equal duration and different peak amplitude, and reported the one perceived as stronger. For each stimulus duration, we determined the smallest detectable change in stimulus intensity (differential threshold) for a reference velocity of 15 deg/s. Results indicate that differential thresholds decrease with stimulus duration and asymptotically converge to a constant, positive value. This suggests that the central nervous system accumulates sensory information on self-motion over time, resulting in improved discrimination performances. Observed trends in differential thresholds are consistent with predictions based on a drift diffusion model with leaky integration of sensory evidence.

The complex duration perception of emotional faces: effects of face direction.

PubMed

Kliegl, Katrin M; Limbrecht-Ecklundt, Kerstin; Dürr, Lea; Traue, Harald C; Huckauf, Anke

2015-01-01

The perceived duration of emotional face stimuli strongly depends on the expressed emotion. But, emotional faces also differ regarding a number of other features like gaze, face direction, or sex. Usually, these features have been controlled by only using pictures of female models with straight gaze and face direction. Doi and Shinohara (2009) reported that an overestimation of angry faces could only be found when the model's gaze was oriented toward the observer. We aimed at replicating this effect for face direction. Moreover, we explored the effect of face direction on the duration perception sad faces. Controlling for the sex of the face model and the participant, female and male participants rated the duration of neutral, angry, and sad face stimuli of both sexes photographed from different perspectives in a bisection task. In line with current findings, we report a significant overestimation of angry compared to neutral face stimuli that was modulated by face direction. Moreover, the perceived duration of sad face stimuli did not differ from that of neutral faces and was not influenced by face direction. Furthermore, we found that faces of the opposite sex appeared to last longer than those of the same sex. This outcome is discussed with regards to stimulus parameters like the induced arousal, social relevance, and an evolutionary context.

Modifying Speech to Children based on their Perceived Phonetic Accuracy

PubMed Central

Julien, Hannah M.; Munson, Benjamin

2014-01-01

Purpose We examined the relationship between adults' perception of the accuracy of children's speech, and acoustic detail in their subsequent productions to children. Methods Twenty-two adults participated in a task in which they rated the accuracy of 2- and 3-year-old children's word-initial /s/and /∫/ using a visual analog scale (VAS), then produced a token of the same word as if they were responding to the child whose speech they had just rated. Result The duration of adults' fricatives varied as a function of their perception of the accuracy of children's speech: longer fricatives were produced following productions that they rated as inaccurate. This tendency to modify duration in response to perceived inaccurate tokens was mediated by measures of self-reported experience interacting with children. However, speakers did not increase the spectral distinctiveness of their fricatives following the perception of inaccurate tokens. Conclusion These results suggest that adults modify temporal features of their speech in response to perceiving children's inaccurate productions. These longer fricatives are potentially both enhanced input to children, and an error-corrective signal. PMID:22744140

Prevalence and determinants of asthma in adult male leather tannery workers in Karachi, Pakistan: A cross sectional study

PubMed Central

Shahzad, Khurram; Akhtar, Saeed; Mahmud, Sadia

2006-01-01

Background This study aimed to estimate the prevalence and to identify some risk factors of adult asthma in male leather tannery workers in Karachi, Pakistan. Methods A cross sectional study was conducted from August 2003 to March 2004 on leather tannery workers of Karachi, Pakistan. Data were collected from 641 workers engaged in 95 different tanneries in Korangi industrial area selected as sample of convenience. Face to face interviews were performed using a structured pre-tested questionnaire by trained data collectors. Results Prevalence of adult asthma was 10.8% (69/641) in this study population. The prevalence of perceived work-related asthma was 5.3% (34/641). Multivariable logistic regression model showed that after taking into account the age effect, the leather tannery worker were more likely to be asthmatic, if they were illiterate (adjusted OR = 2.13, 95% CI: 1.17–3.88), of Pathan ethnicity (adjusted OR = 2.69; 95% CI: 1.35–5.36), ever-smoked (adjusted OR = 2.22, 95% CI: 1.16–4.26), reportedly never used gloves during different tanning tasks (OR = 3.28; 95% CI : 1.72–6.26). Also, the final model showed a significant interaction between perceived allergy and duration of work. Those who perceived to have allergy were more likely to have asthma if their duration of work was 8 years (adjusted OR = 2.26; 95% CI: 1.19 – 4.29) and this relationship was even stronger if duration was 13 years (adjusted OR = 3.67; 95% CI: 1.98–6.79). Conclusion Prevalence of asthma in leather tannery workers appears to be high and is associated with educational status, ethnicity, smoking, glove use, perceived to have allergy and duration of work. PMID:17144930

Prevalence and determinants of asthma in adult male leather tannery workers in Karachi, Pakistan: a cross sectional study.

PubMed

Shahzad, Khurram; Akhtar, Saeed; Mahmud, Sadia

2006-12-05

This study aimed to estimate the prevalence and to identify some risk factors of adult asthma in male leather tannery workers in Karachi, Pakistan. A cross sectional study was conducted from August 2003 to March 2004 on leather tannery workers of Karachi, Pakistan. Data were collected from 641 workers engaged in 95 different tanneries in Korangi industrial area selected as sample of convenience. Face to face interviews were performed using a structured pre-tested questionnaire by trained data collectors. Prevalence of adult asthma was 10.8% (69/641) in this study population. The prevalence of perceived work-related asthma was 5.3% (34/641). Multivariable logistic regression model showed that after taking into account the age effect, the leather tannery worker were more likely to be asthmatic, if they were illiterate (adjusted OR = 2.13, 95% CI: 1.17-3.88), of Pathan ethnicity (adjusted OR = 2.69; 95% CI: 1.35-5.36), ever-smoked (adjusted OR = 2.22, 95% CI: 1.16-4.26), reportedly never used gloves during different tanning tasks (OR = 3.28; 95% CI : 1.72-6.26). Also, the final model showed a significant interaction between perceived allergy and duration of work. Those who perceived to have allergy were more likely to have asthma if their duration of work was 8 years (adjusted OR = 2.26; 95% CI: 1.19 - 4.29) and this relationship was even stronger if duration was 13 years (adjusted OR = 3.67; 95% CI: 1.98-6.79). Prevalence of asthma in leather tannery workers appears to be high and is associated with educational status, ethnicity, smoking, glove use, perceived to have allergy and duration of work.

Hearing gestures, seeing music: vision influences perceived tone duration.

PubMed

Schutz, Michael; Lipscomb, Scott

2007-01-01

Percussionists inadvertently use visual information to strategically manipulate audience perception of note duration. Videos of long (L) and short (S) notes performed by a world-renowned percussionist were separated into visual (Lv, Sv) and auditory (La, Sa) components. Visual components contained only the gesture used to perform the note, auditory components the acoustic note itself. Audio and visual components were then crossed to create realistic musical stimuli. Participants were informed of the mismatch, and asked to rate note duration of these audio-visual pairs based on sound alone. Ratings varied based on visual (Lv versus Sv), but not auditory (La versus Sa) components. Therefore while longer gestures do not make longer notes, longer gestures make longer sounding notes through the integration of sensory information. This finding contradicts previous research showing that audition dominates temporal tasks such as duration judgment.

The Impact of Heat Exposure and Sleep Restriction on Firefighters' Work Performance and Physiology during Simulated Wildfire Suppression.

PubMed

Vincent, Grace E; Aisbett, Brad; Larsen, Brianna; Ridgers, Nicola D; Snow, Rod; Ferguson, Sally A

2017-02-12

This study was designed to examine the effects of ambient heat on firefighters' physical task performance, and physiological and perceptual responses when sleep restricted during simulated wildfire conditions. Thirty firefighters were randomly allocated to the sleep restricted ( n = 17, SR; 19 °C, 4-h sleep opportunity) or hot and sleep restricted ( n = 13, HOT + SR; 33 °C, 4-h sleep opportunity) condition. Firefighters performed two days of simulated, intermittent, self-paced work circuits comprising six firefighting tasks. Heart rate, and core temperature were measured continuously. After each task, firefighters reported their rating of perceived exertion and thermal sensation. Effort sensation was also reported after each work circuit. Fluids were consumed ad libitum. Urine volume and urine specific gravity were analysed. Sleep was monitored using polysomnography. There were no differences between the SR and HOT + SR groups in firefighters' physiological responses, hydration status, ratings of perceived exertion, motivation, and four of the six firefighting tasks (charged hose advance, rake, hose rolling, static hose hold). Black out hose and lateral repositioning were adversely affected in the HOT + SR group. Working in hot conditions did not appear to consistently impair firefighters work performance, physiology, and perceptual responses. Future research should determine whether such findings remain true when individual tasks are performed over longer durations.

Time flies when we read taboo words.

PubMed

Tipples, Jason

2010-08-01

Does time fly or stand still when one is reading highly arousing words? A temporal bisection task was used to test the effects of sexual taboo words on time perception. Forty participants judged the duration of sexual taboo, high-arousal negative, high-arousal positive, low-arousal negative, low-arousal positive, and category-related neutral words. The results support the hypothesis that sexual taboo stimuli receive more attention and reduce the perceived time that has passed ("time flies")-the duration of high sexual taboo words was underestimated for taboo-word stimuli relative to all other word types. The findings are discussed in the context of internal clock theories of time perception.

Knowledge of Previous Tasks: Task Similarity Influences Bias in Task Duration Predictions

PubMed Central

Thomas, Kevin E.; König, Cornelius J.

2018-01-01

Bias in predictions of task duration has been attributed to misremembering previous task duration and using previous task duration as a basis for predictions. This research sought to further examine how previous task information affects prediction bias by manipulating task similarity and assessing the role of previous task duration feedback. Task similarity was examined through participants performing two tasks 1 week apart that were the same or different. Duration feedback was provided to all participants (Experiment 1), its recall was manipulated (Experiment 2), and its provision was manipulated (Experiment 3). In all experiments, task similarity influenced bias on the second task, with predictions being less biased when the first task was the same task. However, duration feedback did not influence bias. The findings highlight the pivotal role of knowledge about previous tasks in task duration prediction and are discussed in relation to the theoretical accounts of task duration prediction bias. PMID:29881362

The Effect of Task Duration on Event-Based Prospective Memory: A Multinomial Modeling Approach

PubMed Central

Zhang, Hongxia; Tang, Weihai; Liu, Xiping

2017-01-01

Remembering to perform an action when a specific event occurs is referred to as Event-Based Prospective Memory (EBPM). This study investigated how EBPM performance is affected by task duration by having university students (n = 223) perform an EBPM task that was embedded within an ongoing computer-based color-matching task. For this experiment, we separated the overall task’s duration into the filler task duration and the ongoing task duration. The filler task duration is the length of time between the intention and the beginning of the ongoing task, and the ongoing task duration is the length of time between the beginning of the ongoing task and the appearance of the first Prospective Memory (PM) cue. The filler task duration and ongoing task duration were further divided into three levels: 3, 6, and 9 min. Two factors were then orthogonally manipulated between-subjects using a multinomial processing tree model to separate the effects of different task durations on the two EBPM components. A mediation model was then created to verify whether task duration influences EBPM via self-reminding or discrimination. The results reveal three points. (1) Lengthening the duration of ongoing tasks had a negative effect on EBPM performance while lengthening the duration of the filler task had no significant effect on it. (2) As the filler task was lengthened, both the prospective and retrospective components show a decreasing and then increasing trend. Also, when the ongoing task duration was lengthened, the prospective component decreased while the retrospective component significantly increased. (3) The mediating effect of discrimination between the task duration and EBPM performance was significant. We concluded that different task durations influence EBPM performance through different components with discrimination being the mediator between task duration and EBPM performance. PMID:29163277

Quantifying deficits in the perception of fear and anger in morphed facial expressions after bilateral amygdala damage.

PubMed

Graham, Reiko; Devinsky, Orrin; Labar, Kevin S

2007-01-07

Amygdala damage has been associated with impairments in perceiving facial expressions of fear. However, deficits in perceiving other emotions, such as anger, and deficits in perceiving emotion blends have not been definitively established. One possibility is that methods used to index expression perception are susceptible to heuristic use, which may obscure impairments. To examine this, we adapted a task used to examine categorical perception of morphed facial expressions [Etcoff, N. L., & Magee, J. J. (1992). Categorical perception of facial expressions. Cognition, 44(3), 227-240]. In one version of the task, expressions were categorized with unlimited time constraints. In the other, expressions were presented with limited exposure durations to tap more automatic aspects of processing. Three morph progressions were employed: neutral to anger, neutral to fear, and fear to anger. Both tasks were administered to a participant with bilateral amygdala damage (S.P.), age- and education-matched controls, and young controls. The second task was also administered to unilateral temporal lobectomy patients. In the first version, S.P. showed impairments relative to normal controls on the neutral-to-anger and fear-to-anger morphs, but not on the neutral-to-fear morph. However, reaction times suggested that speed-accuracy tradeoffs could account for results. In the second version, S.P. showed impairments on all morph types relative to all other subject groups. A third experiment showed that this deficit did not extend to the perception of morphed identities. These results imply that when heuristics use is discouraged on tasks utilizing subtle emotion transitions, deficits in the perception of anger and anger/fear blends, as well as fear, are evident with bilateral amygdala damage.

The Impact of Heat Exposure and Sleep Restriction on Firefighters’ Work Performance and Physiology during Simulated Wildfire Suppression

PubMed Central

Vincent, Grace E.; Aisbett, Brad; Larsen, Brianna; Ridgers, Nicola D.; Snow, Rod; Ferguson, Sally A.

2017-01-01

This study was designed to examine the effects of ambient heat on firefighters’ physical task performance, and physiological and perceptual responses when sleep restricted during simulated wildfire conditions. Thirty firefighters were randomly allocated to the sleep restricted (n = 17, SR; 19 °C, 4-h sleep opportunity) or hot and sleep restricted (n = 13, HOT + SR; 33 °C, 4-h sleep opportunity) condition. Firefighters performed two days of simulated, intermittent, self-paced work circuits comprising six firefighting tasks. Heart rate, and core temperature were measured continuously. After each task, firefighters reported their rating of perceived exertion and thermal sensation. Effort sensation was also reported after each work circuit. Fluids were consumed ad libitum. Urine volume and urine specific gravity were analysed. Sleep was monitored using polysomnography. There were no differences between the SR and HOT + SR groups in firefighters’ physiological responses, hydration status, ratings of perceived exertion, motivation, and four of the six firefighting tasks (charged hose advance, rake, hose rolling, static hose hold). Black out hose and lateral repositioning were adversely affected in the HOT + SR group. Working in hot conditions did not appear to consistently impair firefighters work performance, physiology, and perceptual responses. Future research should determine whether such findings remain true when individual tasks are performed over longer durations. PMID:28208688

The Dampening Effects of Perceived Teacher Enthusiasm on Class-Related Boredom: The Mediating Role of Perceived Autonomy Support and Task Value

PubMed Central

Cui, Guanyu; Yao, Meilin; Zhang, Xia

2017-01-01

Class-related boredom is commonly experienced by students and it has an impact on their learning engagement and achievements. Previous research has found that perceived teacher enthusiasm might contribute to reducing students’ class-related boredom. However, the mechanism through which perceived teacher enthusiasm affects class-related boredom remains unexplored. The purpose of the present study was to investigate the mediating role of perceived autonomy support and task value in the relationship between teacher enthusiasm and class-related boredom. College students (N = 734) completed questionnaires on perceived teacher enthusiasm, boredom proneness, perceived task difficulty, perceived autonomy support, perceived task value, and class-related boredom. Results showed that after controlling for the effects of demographic variables, boredom proneness, and perceived task difficulty, both perceived autonomy support and task value fully mediated the relationship between perceived teacher enthusiasm and class-related boredom. These findings suggest that students who perceive more teacher enthusiasm might perceive more autonomy support and task value, which in turn reduce the students’ class-related boredom. Limitations in the present study have also been discussed. PMID:28367134

The Dampening Effects of Perceived Teacher Enthusiasm on Class-Related Boredom: The Mediating Role of Perceived Autonomy Support and Task Value.

PubMed

Cui, Guanyu; Yao, Meilin; Zhang, Xia

2017-01-01

Class-related boredom is commonly experienced by students and it has an impact on their learning engagement and achievements. Previous research has found that perceived teacher enthusiasm might contribute to reducing students' class-related boredom. However, the mechanism through which perceived teacher enthusiasm affects class-related boredom remains unexplored. The purpose of the present study was to investigate the mediating role of perceived autonomy support and task value in the relationship between teacher enthusiasm and class-related boredom. College students ( N = 734) completed questionnaires on perceived teacher enthusiasm, boredom proneness, perceived task difficulty, perceived autonomy support, perceived task value, and class-related boredom. Results showed that after controlling for the effects of demographic variables, boredom proneness, and perceived task difficulty, both perceived autonomy support and task value fully mediated the relationship between perceived teacher enthusiasm and class-related boredom. These findings suggest that students who perceive more teacher enthusiasm might perceive more autonomy support and task value, which in turn reduce the students' class-related boredom. Limitations in the present study have also been discussed.

Triple dissociation of duration perception regulating mechanisms: Top-down attention is inherent.

PubMed

Lin, Yong-Jun; Shimojo, Shinsuke

2017-01-01

The brain constantly adjusts perceived duration based on the recent event history. One such lab phenomenon is subjective time expansion induced in an oddball paradigm ("oddball chronostasis"), where the duration of a distinct item (oddball) appears subjectively longer when embedded in a series of other repeated items (standards). Three hypotheses have been separately proposed but it remains unresolved which or all of them are true: 1) attention prolongs oddball duration, 2) repetition suppression reduces standards duration, and 3) accumulative temporal preparation (anticipation) expedites the perceived item onset so as to lengthen its duration. We thus conducted critical systematic experiments to dissociate the relative contribution of all hypotheses, by orthogonally manipulating sequences types (repeated, ordered, or random) and target serial positions. Participants' task was to judge whether a target lasts shorter or longer than its reference. The main finding was that a random item sequence still elicited significant chronostasis even though each item was odd. That is, simply being a target draws top-down attention and induces chronostasis. In Experiments 1 (digits) and 2 (orientations), top-down attention explained about half of the effect while saliency/adaptation explained the other half. Additionally, for non-repeated (ordered and random) sequence types, a target with later serial position still elicited stronger chronostasis, favoring a temporal preparation over a repetition suppression account. By contrast, in Experiment 3 (colors), top-down attention was likely the sole factor. Consequently, top-down attention is necessary and sometimes sufficient to explain oddball chronostasis; saliency/adaptation and temporal preparation are contingent factors. These critical boundary conditions revealed in our study serve as quantitative constraints for neural models of duration perception.

Rail commuting duration and passenger stress.

PubMed

Evans, Gary W; Wener, Richard E

2006-05-01

Over 100 million Americans commute to work every weekday. Little is known, however, about how this aspect of work, which may indeed be the most stressful aspect of the job for some, affects human health and well-being. The authors studied a sample of 208 male and female suburban rail commuters who took the train to Manhattan, New York. The greater the duration of the commute, the larger the magnitude of salivary cortisol elevations in reference to resting baseline levels, the less the commuter's persistence on a task at the end of the commute, and the greater the levels of perceived stress. These effects were not moderated by gender. Commuting stress is an important and largely overlooked aspect of environmental health. 2006 APA, all rights reserved

Object size determines the spatial spread of visual time

PubMed Central

McGraw, Paul V.; Roach, Neil W.; Whitaker, David

2016-01-01

A key question for temporal processing research is how the nervous system extracts event duration, despite a notable lack of neural structures dedicated to duration encoding. This is in stark contrast with the orderly arrangement of neurons tasked with spatial processing. In this study, we examine the linkage between the spatial and temporal domains. We use sensory adaptation techniques to generate after-effects where perceived duration is either compressed or expanded in the opposite direction to the adapting stimulus' duration. Our results indicate that these after-effects are broadly tuned, extending over an area approximately five times the size of the stimulus. This region is directly related to the size of the adapting stimulus—the larger the adapting stimulus the greater the spatial spread of the after-effect. We construct a simple model to test predictions based on overlapping adapted versus non-adapted neuronal populations and show that our effects cannot be explained by any single, fixed-scale neural filtering. Rather, our effects are best explained by a self-scaled mechanism underpinned by duration selective neurons that also pool spatial information across earlier stages of visual processing. PMID:27466452

The Effects of Mental Fatigue on Physical Performance: A Systematic Review.

PubMed

Van Cutsem, Jeroen; Marcora, Samuele; De Pauw, Kevin; Bailey, Stephen; Meeusen, Romain; Roelands, Bart

2017-08-01

Mental fatigue is a psychobiological state caused by prolonged periods of demanding cognitive activity. It has recently been suggested that mental fatigue can affect physical performance. Our objective was to evaluate the literature on impairment of physical performance due to mental fatigue and to create an overview of the potential factors underlying this effect. Two electronic databases, PubMed and Web of Science (until 28 April 2016), were searched for studies designed to test whether mental fatigue influenced performance of a physical task or influenced physiological and/or perceptual responses during the physical task. Studies using short (<30 min) self-regulatory depletion tasks were excluded from the review. A total of 11 articles were included, of which six were of strong and five of moderate quality. The general finding was a decline in endurance performance (decreased time to exhaustion and self-selected power output/velocity or increased completion time) associated with a higher than normal perceived exertion. Physiological variables traditionally associated with endurance performance (heart rate, blood lactate, oxygen uptake, cardiac output, maximal aerobic capacity) were unaffected by mental fatigue. Maximal strength, power, and anaerobic work were not affected by mental fatigue. The duration and intensity of the physical task appear to be important factors in the decrease in physical performance due to mental fatigue. The most important factor responsible for the negative impact of mental fatigue on endurance performance is a higher perceived exertion.

Phonological perception by birds: budgerigars can perceive lexical stress.

PubMed

Hoeschele, Marisa; Fitch, W Tecumseh

2016-05-01

Metrical phonology is the perceptual "strength" in language of some syllables relative to others. The ability to perceive lexical stress is important, as it can help a listener segment speech and distinguish the meaning of words and sentences. Despite this importance, there has been little comparative work on the perception of lexical stress across species. We used a go/no-go operant paradigm to train human participants and budgerigars (Melopsittacus undulatus) to distinguish trochaic (stress-initial) from iambic (stress-final) two-syllable nonsense words. Once participants learned the task, we presented both novel nonsense words, and familiar nonsense words that had certain cues removed (e.g., pitch, duration, loudness, or vowel quality) to determine which cues were most important in stress perception. Members of both species learned the task and were then able to generalize to novel exemplars, showing categorical learning rather than rote memorization. Tests using reduced stimuli showed that humans could identify stress patterns with amplitude and pitch alone, but not with only duration or vowel quality. Budgerigars required more than one cue to be present and had trouble if vowel quality or amplitude were missing as cues. The results suggest that stress patterns in human speech can be decoded by other species. Further comparative stress-perception research with more species could help to determine what species characteristics predict this ability. In addition, tests with a variety of stimuli could help to determine how much this ability depends on general pattern learning processes versus vocalization-specific cues.

Filling the blanks in temporal intervals: the type of filling influences perceived duration and discrimination performance

PubMed Central

Horr, Ninja K.; Di Luca, Massimiliano

2015-01-01

In this work we investigate how judgments of perceived duration are influenced by the properties of the signals that define the intervals. Participants compared two auditory intervals that could be any combination of the following four types: intervals filled with continuous tones (filled intervals), intervals filled with regularly-timed short tones (isochronous intervals), intervals filled with irregularly-timed short tones (anisochronous intervals), and intervals demarcated by two short tones (empty intervals). Results indicate that the type of intervals to be compared affects discrimination performance and induces distortions in perceived duration. In particular, we find that duration judgments are most precise when comparing two isochronous and two continuous intervals, while the comparison of two anisochronous intervals leads to the worst performance. Moreover, we determined that the magnitude of the distortions in perceived duration (an effect akin to the filled duration illusion) is higher for tone sequences (no matter whether isochronous or anisochronous) than for continuous tones. Further analysis of how duration distortions depend on the type of filling suggests that distortions are not only due to the perceived duration of the two individual intervals, but they may also be due to the comparison of two different filling types. PMID:25717310

Temporal expectation in focal hand dystonia.

PubMed

Avanzino, Laura; Martino, Davide; Martino, Isadora; Pelosin, Elisa; Vicario, Carmelo M; Bove, Marco; Defazio, Gianni; Abbruzzese, Giovanni

2013-02-01

Patients with writer's cramp present sensory and representational abnormalities relevant to motor control, such as impairment in the temporal discrimination between tactile stimuli and in pure motor imagery tasks, like the mental rotation of corporeal and inanimate objects. However, only limited information is available on the ability of patients with dystonia to process the time-dependent features (e.g. speed) of movement in real time. The processing of time-dependent features of movement has a crucial role in predicting whether the outcome of a complex motor sequence, such as handwriting or playing a musical passage, will be consistent with its ultimate goal, or results instead in an execution error. In this study, we sought to evaluate the implicit ability to perceive the temporal outcome of different movements in a group of patients with writer's cramp. Fourteen patients affected by writer's cramp in the right hand and 17 age- and gender-matched healthy subjects were recruited for the study. Subjects were asked to perform a temporal expectation task by predicting the end of visually perceived human body motion (handwriting, i.e. the action performed by the human body segment specifically affected by writer's cramp) or inanimate object motion (a moving circle reaching a spatial target). Videos representing movements were shown in full before experimental trials; the actual tasks consisted of watching the same videos, but interrupted after a variable interval ('pre-dark') from its onset by a dark interval of variable duration. During the 'dark' interval, subjects were asked to indicate when the movement represented in the video reached its end by clicking on the space bar of the keyboard. We also included a visual working memory task. Performance on the timing task was analysed measuring the absolute value of timing error, the coefficient of variability and the percentage of anticipation responses. Patients with writer's cramp exhibited greater absolute timing error compared with control subjects in the human body motion task (whereas no difference was observed in the inanimate object motion task). No effect of group was documented on the visual working memory tasks. Absolute timing error on the human body motion task did not significantly correlate with symptom severity, disease duration or writing speed. Our findings suggest an alteration of the writing movement representation at a central level and are consistent with the view that dystonia is not a purely motor disorder, but it also involves non-motor (sensory, cognitive) aspects related to movement processing and planning.

Thinking aloud influences perceived time.

PubMed

Hertzum, Morten; Holmegaard, Kristin Due

2015-02-01

We investigate whether thinking aloud influences perceived time. Thinking aloud is widely used in usability evaluation, yet it is debated whether thinking aloud influences thought and behavior. If thinking aloud is restricted to the verbalization of information to which a person is already attending, there is evidence that thinking aloud does not influence thought and behavior. In an experiment, 16 thinking-aloud participants and 16 control participants solved a code-breaking task 24 times each. Participants estimated task duration. The 24 trials involved two levels of time constraint (timed, untimed) and resulted in two levels of success (solved, unsolved). The ratio of perceived time to clock time was lower for thinking-aloud than control participants. Participants overestimated time by an average of 47% (thinking aloud) and 94% (control). The effect of thinking aloud on time perception also held separately for timed, untimed, solved, and unsolved trials. Thinking aloud (verbalization at Levels 1 and 2) influences perceived time. Possible explanations of this effect include that thinking aloud may require attention, cause a processing shift that overshadows the perception of time, or increase mental workload. For usability evaluation, this study implies that time estimates made while thinking aloud cannot be compared with time estimates made while not thinking aloud, that ratings of systems experienced while thinking aloud may be inaccurate (because the experience of time influences other experiences), and that it may therefore be considered to replace concurrent thinking aloud with retrospective thinking aloud when evaluations involve time estimation.

Pitch structure, but not selective attention, affects accent weightings in metrical grouping.

PubMed

Prince, Jon B

2014-10-01

Among other cues, pitch and temporal accents contribute to grouping in musical sequences. However, exactly how they combine remains unclear, possibly because of the role of structural organization. In 3 experiments, participants rated the perceived metrical grouping of sequences that either adhered to the rules of tonal Western musical pitch structure (musical key) or did not (atonal). The tonal status of sequences did not provide any grouping cues and was irrelevant to the task. Experiment 1 established equally strong levels of pitch leap accents and duration accents in baseline conditions, which were then recombined in subsequent experiments. Neither accent type was stronger or weaker for tonal and atonal contexts. In Experiment 2, pitch leap accents dominated over duration accents, but the extent of this advantage was greater when sequences were tonal. Experiment 3 ruled out an attentional origin of this effect by replicating this finding while explicitly manipulating attention to pitch or duration accents between participant groups. Overall, the presence of tonal pitch structure made the dimension of pitch more salient at the expense of time. These findings support a dimensional salience framework in which the presence of organizational structure prioritizes the processing of the more structured dimension regardless of task relevance, independent from psychophysical difficulty, and impervious to attentional allocation.

High levels of time contraction in young children in dual tasks are related to their limited attention capacities.

PubMed

Hallez, Quentin; Droit-Volet, Sylvie

2017-09-01

Numerous studies have shown that durations are judged shorter in a dual-task condition than in a simple-task condition. The resource-based theory of time perception suggests that this is due to the processing of temporal information, which is a demanding cognitive task that consumes limited attention resources. Our study investigated whether this time contraction in a dual-task condition is greater in younger children and, if so, whether this is specifically related to their limited attention capacities. Children aged 5-7years were given a temporal reproduction task in a simple-task condition and a dual-task condition. In addition, different neuropsychological tests were used to assess not only their attention capacities but also their capacities in terms of working memory and information processing speed. The results showed a shortening of perceived time in the dual task compared with the simple task, and this increased as age decreased. The extent of this shortening effect was directly linked to younger children's limited attentional capacities; the lower their attentional capacities, the greater the time contraction. This study demonstrated that children's errors in time judgments are linked to their cognitive capacities rather than to capacities that are specific to time. Copyright © 2017 Elsevier Inc. All rights reserved.

Effects of Memory Load and Test Position on Short-Duration Sustained Attention Tasks.

PubMed

Laurie-Rose, Cynthia; Frey, Meredith C; Sibata, Erick; Zamary, Amanda

2015-01-01

The current study applies a dual-task working memory and vigilance task to examine sustained attention performance and perceived workload in a multi-instrument battery. In Experiment 1 we modified a task developed by Helton and Russell (2011) to examine declines in performance and to assess the effects of its position within a larger battery. Experiment 1 failed to reveal a sensitivity decrement, and test position revealed only spurious influence. Workload scores derived from the NASA-TLX fell at the high end of the scale, with mental and temporal demand receiving the highest ratings. In Experiment 2, we modified the dual task to place more emphasis on attention rather than working memory. Results revealed a significant decline in performance across the vigil for the perceptual sensitivity index A'. Test position (early vs. late) effects appeared with the reaction time variability measure, with performance becoming more variable when the task appeared in the latter half of the battery. Workload scores varied according to position in the battery: Workload scores were higher when the vigilance task appeared in the latter half of the battery. Practical and theoretical implications are discussed.

Recreation Embedded State Tuning for Optimal Readiness and Effectiveness (RESTORE)

NASA Technical Reports Server (NTRS)

Pope, Alan T.; Prinzel, Lawrence J., III

2005-01-01

Physiological self-regulation training is a behavioral medicine intervention that has demonstrated capability to improve psychophysiological coping responses to stressful experiences and to foster optimal behavioral and cognitive performance. Once developed, these psychophysiological skills require regular practice for maintenance. A concomitant benefit of these physiologically monitored practice sessions is the opportunity to track crew psychophysiological responses to the challenges of the practice task in order to detect shifts in adaptability that may foretell performance degradation. Long-duration missions will include crew recreation periods that will afford physiological self-regulation training opportunities. However, to promote adherence to the regimen, the practice experience that occupies their recreation time must be perceived by the crew as engaging and entertaining throughout repeated reinforcement sessions on long-duration missions. NASA biocybernetic technologies and publications have developed a closed-loop concept that involves adjusting or modulating (cybernetic, for governing) a person's task environment based upon a comparison of that person's physiological responses (bio-) with a training or performance criterion. This approach affords the opportunity to deliver physiological self-regulation training in an entertaining and motivating fashion and can also be employed to create a conditioned association between effective performance state and task execution behaviors, while enabling tracking of individuals psychophysiological status over time in the context of an interactive task challenge. This paper describes the aerospace spin-off technologies in this training application area as well as the current spin-back application of the technologies to long-duration missions - the Recreation Embedded State Tuning for Optimal Readiness and Effectiveness (RESTORE) concept. The RESTORE technology is designed to provide a physiological self-regulation training countermeasure for maintaining and reinforcing cognitive readiness, resilience under psychological stress, and effective mood states in long-duration crews. The technology consists of a system for delivering physiological self-regulation training and for tracking crew central and autonomic nervous system function; the system interface is designed to be experienced as engaging and entertaining throughout repeated training sessions on long-duration missions. Consequently, this self-management technology has threefold capability for recreation, behavioral health problem prophylaxis and remediation, and psychophysiological assay. The RESTORE concept aims to reduce the risk of future manned exploration missions by enhancing the capability of individual crewmembers to self-regulate cognitive states through recreation-embedded training protocols to effectively deal with the psychological toll of long-duration space flight.

Perceived task complexity of trunk stability exercises.

PubMed

McPhee, Megan; Tucker, Kylie J; Wan, Alan; MacDonald, David A

2017-02-01

Perceived task complexity can impact participation in an exercise programme and the level of skill acquisition resulting from participation. Although trunk stability exercises are commonly included in the management of people with low back pain, potential differences in perceived task complexity between those exercises have not been investigated previously. To investigate the perceived task complexity following first time instruction of two common stability exercises: the abdominal brace and abdominal hollow. Cross-sectional. Twenty-four naïve healthy participants received instruction in the performance of an abdominal brace and an abdominal hollow with feedback. Participants rated their perceived task complexity (mental, physical, and temporal demand, performance, effort, frustration) for each exercise on the NASA-Task Load Index. The abdominal hollow was associated with higher perceived mental demand than the abdominal brace (p = 0.01), and required more time to learn (p < 0.01). The abdominal brace was associated with greater mental demand and frustration when performed after the abdominal hollow than before. This study has provided the first evidence for differences in perceived task complexity between two commonly used trunk stability exercises. Those differences in perceived task complexity may influence the selection of exercises intended to enhance the robustness of spinal stability. Copyright © 2016 Elsevier Ltd. All rights reserved.

My action lasts longer: Potential link between subjective time and agency during voluntary action.

PubMed

Imaizumi, Shu; Asai, Tomohisa

2017-05-01

Time perception distorts across different phases of bodily movement. During motor execution, sensory feedback matching an internal sensorimotor prediction is perceived to last longer. The sensorimotor prediction also underlies sense of agency. We investigated association between subjective time and agency during voluntary action. Participants performed hand action while watching a video feedback of their hand with various delays to manipulate agency. The perceived duration and agency over the video feedback were judged. Minimal delay of the video feedback resulted in longer perceived duration than the actual duration and stronger agency, while substantial feedback delay resulted in shorter perceived duration and weaker agency. These fluctuations of perceived duration and agency were nullified by the feedback of other's hand instead of their own, but not by inverted feedback from a third-person perspective. Subjective time during action might be associated with agency stemming from sensorimotor prediction, and self-other distinction based on bodily appearance. Copyright © 2017 Elsevier Inc. All rights reserved.

Space Station Habitability Recommendations Based on a Systematic Comparative Analysis of Analogous Conditions

NASA Technical Reports Server (NTRS)

Stuster, Jack W.

1986-01-01

Conditions analogous to the proposed NASA Space Station are systematically analyzed in order to extrapolate design guidelines and recommendations concerning habitability and crew productivity. Analogous environments studied included Skylab, Sealab, Tektite, submarines, Antarctic stations and oil drilling platforms, among others. These analogues were compared and rated for size and composition of group, social organization, preparedness for mission, duration of tour, types of tasks, physical and psychological isolation, personal motivation, perceived risk, and quality of habitat and life support conditions. One-hundred design recommendations concerning, sleep, clothing, exercise, medical support, personal hygiene, food preparation, group interaction, habitat aesthetics, outside communications, recreational opportunities, privacy and personal space, waste disposal, onboard training, simulation and task preparation, and behavioral and physiological requirements associated with a microgravity environment, are provided.

Electric versus hydraulic hospital beds: differences in use during basic nursing tasks.

PubMed

Capodaglio, Edda Maria

2013-01-01

Biomechanical, postural and ergonomic aspects during real patient-assisting tasks performed by nurses using an electric versus a hydraulic hospital bed were observed. While there were no differences in the flexed postures the nurses adopted, longer performance times were recorded when electric beds were used. Subjective effort, force exertion and lumbar shear forces exceeding safety limits proved electric beds were superior. Patients' dependency level seemed to influence the type of nurses' intervention (duration and force actions), irrespective of the bed used. The nurses greatly appreciated the electric bed. Its use seemed to reduce the level of effort perceived during care giving and the postural load during critical subtasks. Ergonomics and organizational problems related to adopting electric beds in hospital wards should be addressed further to make their use more efficient.

The benefits of mystery in nature on attention: assessing the impacts of presentation duration

PubMed Central

Szolosi, Andrew M.; Watson, Jason M.; Ruddell, Edward J.

2014-01-01

Although research has provided prodigious evidence in support of the cognitive benefits that natural settings have over urban settings, all nature is not equal. Within nature, natural settings that contain mystery are often among the most preferred nature scenes. With the prospect of acquiring new information, scenes of this type could more effectively elicit a person's sense of fascination, enabling that person to rest the more effortful forms of attention. The present study examined the direct cognitive benefits that mystery in nature has on attention. Settings of this sort presumably evoke a form of attention that is undemanding or effortless. In order to investigate that notion, participants (n = 144) completed a Recognition Memory Task (RMT) that evaluated recognition performance based on the presence of mystery and presentation duration (300 ms, 1 s, 5 s, and 10 s). Results revealed that with additional viewing time, images perceived high in mystery achieved greater improvements in recognition performance when compared to those images perceived low in mystery. Tests for mediation showed that the effect mystery had on recognition performance occurred through perceptions of fascination. Implications of these and other findings are discussed in the context of Attention Restoration Theory. PMID:25505441

Changes in apparent duration follow shifts in perceptual timing

PubMed Central

Bruno, Aurelio; Ayhan, Inci; Johnston, Alan

2015-01-01

It is well established that the apparent duration of moving visual objects is greater at higher as compared to slower speeds. Here we report the effects of acceleration and deceleration on the perceived duration of a drifting grating with average speed kept constant (10°/s).For acceleration, increasing the speed range progressively reduced perceived duration. The magnitude of apparent duration compression was determined by speed rather than temporal frequency and was proportional to speed range (independent of standard duration) rather than acceleration. The perceived duration reduction was also proportional to the standard length. The effects of increases and decreases in speed were highly asymmetric. Reducing speed through the interval induced a moderate increase in perceived duration. These results could not be explained by changes in apparent onset or offset or differences in perceived average speed between intervals containing increasing speed and intervals containing decreasing speed. Paradoxically, for intervals combining increasing speed and decreasing speed, compression only occurred when increasing speed occurred in the second half of the interval. We show that this pattern of results in the duration domain was concomitant with changes in the reported direction of apparent motion of Gaussian blobs, embedded in intervals of increasing or decreasing speed, that could be predicted from adaptive changes in the temporal impulse response function. We detected similar changes after flicker adaptation, suggesting that the two effects might be linked through changes in the temporal tuning of visual filters. PMID:26024450

Adolescent-perceived parent and teacher overestimation of mathematics ability: Developmental implications for students' mathematics task values.

PubMed

Gniewosz, Burkhard; Watt, Helen M G

2017-07-01

This study examines whether and how student-perceived parents' and teachers' overestimation of students' own perceived mathematical ability can explain trajectories for adolescents' mathematical task values (intrinsic and utility) controlling for measured achievement, following expectancy-value and self-determination theories. Longitudinal data come from a 3-cohort (mean ages 13.25, 12.36, and 14.41 years; Grades 7-10), 4-wave data set of 1,271 Australian secondary school students. Longitudinal structural equation models revealed positive effects of student-perceived overestimation of math ability by parents and teachers on students' intrinsic and utility math task values development. Perceived parental overestimations predicted intrinsic task value changes between all measurement occasions, whereas utility task value changes only were predicted between Grades 9 and 10. Parental influences were stronger for intrinsic than utility task values. Teacher influences were similar for both forms of task values and commenced after the curricular school transition in Grade 8. Results support the assumptions that the perceived encouragement conveyed by student-perceived mathematical ability beliefs of parents and teachers, promote positive mathematics task values development. Moreover, results point to different mechanisms underlying parents' and teachers' support. Finally, the longitudinal changes indicate transition-related increases in the effects of student-perceived overestimations and stronger effects for intrinsic than utility values. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

How long did it last? You would better ask a human

PubMed Central

Lacquaniti, Francesco; Carrozzo, Mauro; d’Avella, Andrea; La Scaleia, Barbara; Moscatelli, Alessandro; Zago, Myrka

2014-01-01

In the future, human-like robots will live among people to provide company and help carrying out tasks in cooperation with humans. These interactions require that robots understand not only human actions, but also the way in which we perceive the world. Human perception heavily relies on the time dimension, especially when it comes to processing visual motion. Critically, human time perception for dynamic events is often inaccurate. Robots interacting with humans may want to see the world and tell time the way humans do: if so, they must incorporate human-like fallacy. Observers asked to judge the duration of brief scenes are prone to errors: perceived duration often does not match the physical duration of the event. Several kinds of temporal distortions have been described in the specialized literature. Here we review the topic with a special emphasis on our work dealing with time perception of animate actors versus inanimate actors. This work shows the existence of specialized time bases for different categories of targets. The time base used by the human brain to process visual motion appears to be calibrated against the specific predictions regarding the motion of human figures in case of animate motion, while it can be calibrated against the predictions of motion of passive objects in case of inanimate motion. Human perception of time appears to be strictly linked with the mechanisms used to control movements. Thus, neural time can be entrained by external cues in a similar manner for both perceptual judgments of elapsed time and in motor control tasks. One possible strategy could be to implement in humanoids a unique architecture for dealing with time, which would apply the same specialized mechanisms to both perception and action, similarly to humans. This shared implementation might render the humanoids more acceptable to humans, thus facilitating reciprocal interactions. PMID:24478694

How long did it last? You would better ask a human.

PubMed

Lacquaniti, Francesco; Carrozzo, Mauro; d'Avella, Andrea; La Scaleia, Barbara; Moscatelli, Alessandro; Zago, Myrka

2014-01-01

In the future, human-like robots will live among people to provide company and help carrying out tasks in cooperation with humans. These interactions require that robots understand not only human actions, but also the way in which we perceive the world. Human perception heavily relies on the time dimension, especially when it comes to processing visual motion. Critically, human time perception for dynamic events is often inaccurate. Robots interacting with humans may want to see the world and tell time the way humans do: if so, they must incorporate human-like fallacy. Observers asked to judge the duration of brief scenes are prone to errors: perceived duration often does not match the physical duration of the event. Several kinds of temporal distortions have been described in the specialized literature. Here we review the topic with a special emphasis on our work dealing with time perception of animate actors versus inanimate actors. This work shows the existence of specialized time bases for different categories of targets. The time base used by the human brain to process visual motion appears to be calibrated against the specific predictions regarding the motion of human figures in case of animate motion, while it can be calibrated against the predictions of motion of passive objects in case of inanimate motion. Human perception of time appears to be strictly linked with the mechanisms used to control movements. Thus, neural time can be entrained by external cues in a similar manner for both perceptual judgments of elapsed time and in motor control tasks. One possible strategy could be to implement in humanoids a unique architecture for dealing with time, which would apply the same specialized mechanisms to both perception and action, similarly to humans. This shared implementation might render the humanoids more acceptable to humans, thus facilitating reciprocal interactions.

The Influence of Communicative Competence on Perceived Task, Social and Physical Attraction.

ERIC Educational Resources Information Center

Duran, Robert L.; Kelly, Lynne

1988-01-01

Examines whether communicative competence influences perceived task, social, and physical attractiveness. Results indicated that communicative competence accounted for 17 percent, 14 percent and 8 percent of the variance in perceived task, social, and physical attractiveness, respectively. (MM)

Cognitive and Physical Fatigue Tasks Enhance Pain, Cognitive Fatigue and Physical Fatigue in People with Fibromyalgia

PubMed Central

Dailey, Dana L; Keffala, Valerie J; Sluka, Kathleen A

2014-01-01

Objective Fibromyalgia is a condition characterized by chronic widespread muscle pain and fatigue. The primary objective of this study was to determine if pain, perceived cognitive fatigue, and perceived physical fatigue were enhanced in participants with fibromyalgia compared to healthy controls during a cognitive fatigue task, a physical fatigue task and a dual fatigue task. Methods Twenty four people with fibromyalgia and 33 healthy controls completed pain, fatigue and function measures. A cognitive fatigue task (Controlled Oral Word Association Test) and physical fatigue task (Valpar peg test) were done individually and combined for a dual fatigue task. Resting pain, perceived cognitive fatigue and perceived physical fatigue were assessed during each task using visual analogue scales. Function was assessed with shoulder range of motion and grip. Results People with fibromyalgia had significantly higher increases in pain, cognitive fatigue and physical fatigue when compared to healthy controls after completion of a cognitive fatigue task, a physical fatigue task, or a dual fatigue task (p<0.01). People with fibromyalgia performed equivalently on measures of physical performance and cognitive performance on the physical and cognitive fatigue tasks, respectively. Conclusions These data show that people with fibromyalgia show larger increases in pain, perceived cognitive fatigue and perceived physical fatigue to both cognitive and physical fatigue tasks compared to healthy controls. The increases in pain and fatigue during cognitive and physical fatigue tasks could influence subject participation in daily activities and rehabilitation. PMID:25074583

Time on your hands: Perceived duration of sensory events is biased toward concurrent actions.

PubMed

Yon, Daniel; Edey, Rosanna; Ivry, Richard B; Press, Clare

2017-02-01

Perceptual systems must rapidly generate accurate representations of the world from sensory inputs that are corrupted by internal and external noise. We can typically obtain more veridical representations by integrating information from multiple channels, but this integration can lead to biases when inputs are, in fact, not from the same source. Although a considerable amount is known about how different sources of information are combined to influence what we perceive, it is not known whether temporal features are combined. It is vital to address this question given the divergent predictions made by different models of cue combination and time perception concerning the plausibility of cross-modal temporal integration, and the implications that such integration would have for research programs in action control and social cognition. Here we present four experiments investigating the influence of movement duration on the perceived duration of an auditory tone. Participants either explicitly (Experiments 1-2) or implicitly (Experiments 3-4) produced hand movements of shorter or longer durations, while judging the duration of a concurrently presented tone (500-950 ms in duration). Across all experiments, judgments of tone duration were attracted toward the duration of executed movements (i.e., tones were perceived to be longer when executing a movement of longer duration). Our results demonstrate that temporal information associated with movement biases perceived auditory duration, placing important constraints on theories modeling cue integration for state estimation, as well as models of time perception, action control and social cognition. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Goal orientation, perceived task outcome and task demands in mathematics tasks: effects on students' attitude in actual task settings.

PubMed

Seegers, Gerard; van Putten, Cornelis M; de Brabander, Cornelis J

2002-09-01

In earlier studies, it has been found that students' domain-specific cognitions and personal learning goals (goal orientation) influence task-specific appraisals of actual learning tasks. The relations between domain-specific and task-specific variables have been specified in the model of adaptive learning. In this study, additional influences, i.e., perceived task outcome on a former occasion and variations in task demands, were investigated. The purpose of this study was to identify personality and situational variables that mediate students' attitude when confronted with a mathematics task. Students worked on a mathematics task in two subsequent sessions. Effects of perceived task outcome at the first session on students' attitude at the second session were investigated. In addition, we investigated how differences in task demands influenced students' attitude. Variations in task demands were provoked by different conditions in task-instruction. In one condition, students were told that the result on the test would add to their mark on mathematics. This outcome orienting condition was contrasted with a task-orienting condition where students were told that the results on the test would not be used to give individual grades. Participants were sixth grade students (N = 345; aged 11-12 years) from 14 primary schools. Multivariate and univariate analyses of (co)variance were applied to the data. Independent variables were goal orientation, task demands, and perceived task outcome, with task-specific variables (estimated competence for the task, task attraction, task relevance, and willingness to invest effort) as the dependent variables. The results showed that previous perceived task outcome had a substantial impact on students' attitude. Additional but smaller effects were found for variation in task demands. Furthermore, effects of previous perceived task outcome and task demands were related to goal orientation. The resulting pattern confirmed that, in general, performance-oriented learning goals emphasised the negative impact of failure experiences, whereas task-oriented learning goals had a strengthening effect on how success experiences influenced students' attitude.

Perceived time slows during fleeting fun or fear.

PubMed

Corke, Mike; Bell, Jason; Goodhew, Stephanie C; Smithson, Michael; Edwards, Mark

2018-02-01

Previous psychophysical studies at durations greater than 1000 ms have confirmed the anecdotal reports of an increase in the perceived duration of both positively and negatively valenced emotive stimuli; however, the results of studies at durations less than 1000 ms have been inconsistent. This study further investigated the effect of valence on the perception of durations less than 1000 ms. We used both positively and negatively valenced stimuli in order to compare their effects on the distortion of duration, and we tested multiple data points within the sub-one-second range. We found an increase in the perceived duration of both positively and negatively valenced emotional stimuli at all data points. This is consistent with studies at durations longer than 1000 ms and also with models of temporal processing. We also confirmed that Weber fractions, within the range tested, followed the generalized form of Weber's law.

Your visual system provides all the information you need to make moral judgments about generic visual events.

PubMed

De Freitas, Julian; Alvarez, George A

2018-05-28

To what extent are people's moral judgments susceptible to subtle factors of which they are unaware? Here we show that we can change people's moral judgments outside of their awareness by subtly biasing perceived causality. Specifically, we used subtle visual manipulations to create visual illusions of causality in morally relevant scenarios, and this systematically changed people's moral judgments. After demonstrating the basic effect using simple displays involving an ambiguous car collision that ends up injuring a person (E1), we show that the effect is sensitive on the millisecond timescale to manipulations of task-irrelevant factors that are known to affect perceived causality, including the duration (E2a) and asynchrony (E2b) of specific task-irrelevant contextual factors in the display. We then conceptually replicate the effect using a different paradigm (E3a), and also show that we can eliminate the effect by interfering with motion processing (E3b). Finally, we show that the effect generalizes across different kinds of moral judgments (E3c). Combined, these studies show that obligatory, abstract inferences made by the visual system influence moral judgments. Copyright © 2018 Elsevier B.V. All rights reserved.

Transient emotional events and individual affective traits affect emotion recognition in a perceptual decision-making task.

PubMed

Qiao-Tasserit, Emilie; Garcia Quesada, Maria; Antico, Lia; Bavelier, Daphne; Vuilleumier, Patrik; Pichon, Swann

2017-01-01

Both affective states and personality traits shape how we perceive the social world and interpret emotions. The literature on affective priming has mostly focused on brief influences of emotional stimuli and emotional states on perceptual and cognitive processes. Yet this approach does not fully capture more dynamic processes at the root of emotional states, with such states lingering beyond the duration of the inducing external stimuli. Our goal was to put in perspective three different types of affective states (induced affective states, more sustained mood states and affective traits such as depression and anxiety) and investigate how they may interact and influence emotion perception. Here, we hypothesized that absorption into positive and negative emotional episodes generate sustained affective states that outlast the episode period and bias the interpretation of facial expressions in a perceptual decision-making task. We also investigated how such effects are influenced by more sustained mood states and by individual affect traits (depression and anxiety) and whether they interact. Transient emotional states were induced using movie-clips, after which participants performed a forced-choice emotion classification task with morphed facial expressions ranging from fear to happiness. Using a psychometric approach, we show that negative (vs. neutral) clips increased participants' propensity to classify ambiguous faces as fearful during several minutes. In contrast, positive movies biased classification toward happiness only for those clips perceived as most absorbing. Negative mood, anxiety and depression had a stronger effect than transient states and increased the propensity to classify ambiguous faces as fearful. These results provide the first evidence that absorption and different temporal dimensions of emotions have a significant effect on how we perceive facial expressions.

Transient emotional events and individual affective traits affect emotion recognition in a perceptual decision-making task

PubMed Central

Garcia Quesada, Maria; Antico, Lia; Bavelier, Daphne; Vuilleumier, Patrik; Pichon, Swann

2017-01-01

Both affective states and personality traits shape how we perceive the social world and interpret emotions. The literature on affective priming has mostly focused on brief influences of emotional stimuli and emotional states on perceptual and cognitive processes. Yet this approach does not fully capture more dynamic processes at the root of emotional states, with such states lingering beyond the duration of the inducing external stimuli. Our goal was to put in perspective three different types of affective states (induced affective states, more sustained mood states and affective traits such as depression and anxiety) and investigate how they may interact and influence emotion perception. Here, we hypothesized that absorption into positive and negative emotional episodes generate sustained affective states that outlast the episode period and bias the interpretation of facial expressions in a perceptual decision-making task. We also investigated how such effects are influenced by more sustained mood states and by individual affect traits (depression and anxiety) and whether they interact. Transient emotional states were induced using movie-clips, after which participants performed a forced-choice emotion classification task with morphed facial expressions ranging from fear to happiness. Using a psychometric approach, we show that negative (vs. neutral) clips increased participants’ propensity to classify ambiguous faces as fearful during several minutes. In contrast, positive movies biased classification toward happiness only for those clips perceived as most absorbing. Negative mood, anxiety and depression had a stronger effect than transient states and increased the propensity to classify ambiguous faces as fearful. These results provide the first evidence that absorption and different temporal dimensions of emotions have a significant effect on how we perceive facial expressions. PMID:28151976

The relationship between perceived discomfort of static posture holding and posture holding time.

PubMed

Ogutu, Jack; Park, Woojin

2015-01-01

Few studies have investigated mathematical characteristics of the discomfort-time relationship during prolonged static posture holding (SPH) on an individual basis. Consequently, the discomfort-time relationship is not clearly understood at individual trial level. The objective of this study was to examine discomfort-time sequence data obtained from a large number of maximum-duration SPH trials to understand the perceived discomfort-posture holding time relationship at the individual SPH trial level. Thirty subjects (15 male, 15 female) participated in this study as paid volunteers. The subjects performed maximum-duration SPH trials employing 12 different wholebody static postures. The hand-held load for all the task trials was a ``generic'' box weighing 2 kg. Three mathematical functions, that is, linear, logarithmic and power functions were examined as possible mathematical models for representing individual discomfort-time profiles of SPH trials. Three different time increase patterns (negatively accelerated, linear and positively accelerated) were observed in the discomfort-time sequences data. The power function model with an additive constant term was found to adequately fit most (96.4%) of the observed discomfort-time sequences, and thus, was recommended as a general mathematical representation of the perceived discomfort-posture holding time relationship in SPH. The new knowledge on the nature of the discomfort-time relationship in SPH and the power function representation found in this study will facilitate analyzing discomfort-time data of SPH and developing future posture analysis tools for work-related discomfort control.

Does self-perceived sleep reflect sleep estimated via activity monitors in professional rugby league athletes?

PubMed

Caia, Johnpaul; Thornton, Heidi R; Kelly, Vincent G; Scott, Tannath J; Halson, Shona L; Cupples, Balin; Driller, Matthew W

2018-07-01

This study examined agreement between self-perceived sleep and sleep estimated via activity monitors in professional rugby league athletes. 63 athletes, from three separate teams wore actigraphy monitors for 10.3 ± 3.9 days. During the monitoring period, ratings of perceived sleep quality (on a 1-5 and 1-10 Likert scale), and an estimate of sleep duration were recorded daily. Agreement between sleep estimated via activity monitors and self-perceived sleep was examined using mean bias, Pearson correlation (r) and typical error of the estimate (TEE). 641 nights of sleep were recorded, with a very large, positive correlation observed between sleep duration estimated via activity monitors and subjective sleep duration (r = 0.85), and a TEE of 48 minutes. Mean bias revealed subjective sleep duration overestimated sleep by an average of 19.8 minutes. The relationship between sleep efficiency estimated via activity monitors and self-perceived sleep quality on a 1-5 (r = 0.22) and 1-10 Likert scale (r = 0.28) was limited. The outcomes of this investigation support the use of subjective measures to monitor sleep duration in rugby league athletes when objective means are unavailable. However, practitioners should be aware of the tendency of athletes to overestimate sleep duration.

The role of primary auditory and visual cortices in temporal processing: A tDCS approach.

PubMed

Mioni, G; Grondin, S; Forgione, M; Fracasso, V; Mapelli, D; Stablum, F

2016-10-15

Many studies showed that visual stimuli are frequently experienced as shorter than equivalent auditory stimuli. These findings suggest that timing is distributed across many brain areas and that "different clocks" might be involved in temporal processing. The aim of this study is to investigate, with the application of tDCS over V1 and A1, the specific role of primary sensory cortices (either visual or auditory) in temporal processing. Forty-eight University students were included in the study. Twenty-four participants were stimulated over A1 and 24 participants were stimulated over V1. Participants performed time bisection tasks, in the visual and the auditory modalities, involving standard durations lasting 300ms (short) and 900ms (long). When tDCS was delivered over A1, no effect of stimulation was observed on perceived duration but we observed higher temporal variability under anodic stimulation compared to sham and higher variability in the visual compared to the auditory modality. When tDCS was delivered over V1, an under-estimation of perceived duration and higher variability was observed in the visual compared to the auditory modality. Our results showed more variability of visual temporal processing under tDCS stimulation. These results suggest a modality independent role of A1 in temporal processing and a modality specific role of V1 in the processing of temporal intervals in the visual modality. Copyright © 2016 Elsevier B.V. All rights reserved.

Reward alters the perception of time.

PubMed

Failing, Michel; Theeuwes, Jan

2016-03-01

Recent findings indicate that monetary rewards have a powerful effect on cognitive performance. In order to maximize overall gain, the prospect of earning reward biases visual attention to specific locations or stimulus features improving perceptual sensitivity and processing. The question we addressed in this study is whether the prospect of reward also affects the subjective perception of time. Here, participants performed a prospective timing task using temporal oddballs. The results show that temporal oddballs, displayed for varying durations, presented in a sequence of standard stimuli were perceived to last longer when they signaled a relatively high reward compared to when they signaled no or low reward. When instead of the oddball the standards signaled reward, the perception of the temporal oddball remained unaffected. We argue that by signaling reward, a stimulus becomes subjectively more salient thereby modulating its attentional deployment and distorting how it is perceived in time. Copyright © 2015 Elsevier B.V. All rights reserved.

Does order matter? Investigating the effect of sequence on glance duration during on-road driving

PubMed Central

Roberts, Shannon C.; Reimer, Bryan; Mehler, Bruce

2017-01-01

Previous literature has shown that vehicle crash risks increases as drivers’ off-road glance duration increases. Many factors influence drivers’ glance duration such as individual differences, driving environment, or task characteristics. Theories and past studies suggest that glance duration increases as the task progresses, but the exact relationship between glance sequence and glance durations is not fully understood. The purpose of this study was to examine the effect of glance sequence on glance duration among drivers completing a visual-manual radio tuning task and an auditory-vocal based multi-modal navigation entry task. Eighty participants drove a vehicle on urban highways while completing radio tuning and navigation entry tasks. Forty participants drove under an experimental protocol that required three button presses followed by rotation of a tuning knob to complete the radio tuning task while the other forty participants completed the task with one less button press. Multiple statistical analyses were conducted to measure the effect of glance sequence on glance duration. Results showed that across both tasks and a variety of statistical tests, glance sequence had inconsistent effects on glance duration—the effects varied according to the number of glances, task type, and data set that was being evaluated. Results suggest that other aspects of the task as well as interface design effect glance duration and should be considered in the context of examining driver attention or lack thereof. All in all, interface design and task characteristics have a more influential impact on glance duration than glance sequence, suggesting that classical design considerations impacting driver attention, such as the size and location of buttons, remain fundamental in designing in-vehicle interfaces. PMID:28158301

Human Performance on the Temporal Bisection Task

ERIC Educational Resources Information Center

Kopec, Charles D.; Brody, Carlos D.

2010-01-01

The perception and processing of temporal information are tasks the brain must continuously perform. These include measuring the duration of stimuli, storing duration information in memory, recalling such memories, and comparing two durations. How the brain accomplishes these tasks, however, is still open for debate. The temporal bisection task,…

Effects of the Protestant Work Ethic and Perceived Challenge on Time Allocated to an Experimental Task.

ERIC Educational Resources Information Center

Tang, Thomas Li-Ping

Goal-setting literature has suggested that specific, difficult goals will produce higher performance levels than easy goals. A difficult task or one with negative performance feedback may increase an individual's perceived challenge of the task which may in turn enhance his motivation. Effects of the Protestant work ethic and perceived challenge…

Acute Effects of Cannabis on Breath-Holding Duration

PubMed Central

Farris, Samantha G.; Metrik, Jane

2016-01-01

Distress intolerance (an individual’s perceived or actual inability to tolerate distressing psychological or physiological states) is associated with cannabis use. It is unknown whether a bio-behavioral index of distress intolerance, breath-holding duration, is acutely influenced (increased or decreased) by cannabis. Such information may further inform understanding of the expression of psychological or physiological distress post-cannabis use. This within-subjects study examined whether smoked marijuana with 2.7–3.0 % delta-9-tetrahydrocannabinol (THC), relative to placebo, acutely changed duration of breath-holding. Participants (n = 88; 65.9% male) were non-treatment seeking frequent cannabis users who smoked placebo or active THC cigarette on two separate study days and completed breath-holding task. Controlling for baseline breath-holding duration and participant sex, THC produced significantly lower breath-holding durations relative to placebo. There was a significant interaction of drug administration x frequency of cannabis use, such that THC decreased breath-holding time among less frequent but not among more frequent users. Findings indicate that cannabis may be exacerbating distress intolerance (via breath-holding duration). As compared to less frequent cannabis users, frequent users display tolerance to cannabis’ acute effects including increased ability to tolerate respiratory distress when holding breath. Objective measures of distress intolerance are sensitive to contextual factors such as acute drug intoxication, and may inform the link between cannabis use and the expression of psychological distress. PMID:27454678

Does conflict help or hurt cognitive control? Initial evidence for an inverted U-shape relationship between perceived task difficulty and conflict adaptation.

PubMed

van Steenbergen, Henk; Band, Guido P H; Hommel, Bernhard

2015-01-01

Sequential modulation of congruency effects in conflict tasks indicates that cognitive control quickly adapts to changing task demands. We investigated in four experiments how this behavioral congruency-sequence effect relates to different levels of perceived task difficulty in a flanker and a Stroop task. In addition, online measures of pupil diameter were used as a physiological index of effort mobilization. Consistent with motivational accounts predicting that increased levels of perceived task difficulty will increase effort mobilization only up to a certain limit, reliable dynamic conflict-driven adjustment in cognitive control was only observed when task difficulty was relatively low. Instead, tasks tentatively associated with high levels of difficulty showed no or reversed conflict adaptation. Although the effects could not be linked consistently to effects in self-reported task difficulty in all experiments, regression analyses showed associations between perceived task difficulty and conflict adaptation in some of the experiments, which provides some initial evidence for an inverted U-shape relationship between perceived difficulty and adaptations in cognitive control. Furthermore, high levels of task difficulty were associated with a conflict-driven reduction in pupil dilation, suggesting that pupil dilation can be used as a physiological marker of mental overload. Our findings underscore the importance of developing models that are grounded in motivational accounts of cognitive control.

Does conflict help or hurt cognitive control? Initial evidence for an inverted U-shape relationship between perceived task difficulty and conflict adaptation

PubMed Central

van Steenbergen, Henk; Band, Guido P. H.; Hommel, Bernhard

2015-01-01

Sequential modulation of congruency effects in conflict tasks indicates that cognitive control quickly adapts to changing task demands. We investigated in four experiments how this behavioral congruency-sequence effect relates to different levels of perceived task difficulty in a flanker and a Stroop task. In addition, online measures of pupil diameter were used as a physiological index of effort mobilization. Consistent with motivational accounts predicting that increased levels of perceived task difficulty will increase effort mobilization only up to a certain limit, reliable dynamic conflict-driven adjustment in cognitive control was only observed when task difficulty was relatively low. Instead, tasks tentatively associated with high levels of difficulty showed no or reversed conflict adaptation. Although the effects could not be linked consistently to effects in self-reported task difficulty in all experiments, regression analyses showed associations between perceived task difficulty and conflict adaptation in some of the experiments, which provides some initial evidence for an inverted U-shape relationship between perceived difficulty and adaptations in cognitive control. Furthermore, high levels of task difficulty were associated with a conflict-driven reduction in pupil dilation, suggesting that pupil dilation can be used as a physiological marker of mental overload. Our findings underscore the importance of developing models that are grounded in motivational accounts of cognitive control. PMID:26217287

When Task Conflict Becomes Personal: The Impact of Perceived Team Performance.

PubMed

Guenter, Hannes; van Emmerik, Hetty; Schreurs, Bert; Kuypers, Tom; van Iterson, Ad; Notelaers, Guy

2016-10-01

Although potentially beneficial, task conflict may threaten teams because it often leads to relationship conflict. Prior research has identified a set of interpersonal factors (e.g., team communication, team trust) that help attenuate this association. The purpose of this article is to provide an alternative perspective that focuses on the moderating role of performance-related factors (i.e., perceived team performance). Using social identity theory, we build a model that predicts how task conflict associates with growth in relationship conflict and how perceived team performance influences this association. We test a three-wave longitudinal model by means of random coefficient growth modeling, using data from 60 ongoing teams working in a health care organization. Results provide partial support for our hypotheses. Only when perceived team performance is low, do task conflicts relate with growth in relationship conflict. We conclude that perceived team performance seems to enable teams to uncouple task from relationship conflict.

HIV infection duration, social support and the level of trauma symptoms in a sample of HIV-positive Polish individuals.

PubMed

Rzeszutek, Marcin; Oniszczenko, Włodzimierz; Żebrowska, Magdalena; Firląg-Burkacka, Ewa

2015-01-01

The aim of this study was to investigate the relationship between the average HIV infection duration and the level of quantitatively rated post-traumatic stress disorder (PTSD) symptoms and social support dimensions in a sample of 562 Polish HIV+ adults. Possible moderating effects of social support on the relationship between the average HIV infection duration and the level of PTSD symptoms were also analysed. The results of this study suggest that the average HIV infection duration may intensify PTSD symptoms and deteriorate the perceived availability of social support in HIV+ individuals. However, a positive relationship between HIV infection duration and the level of trauma symptoms was observed only in the group of HIV+ individuals with low perceived available social support, but not in the group of HIV-infected individuals with high perceived available social support. This research provided some new insight into the psychological and social aspects of living with HIV. In particular, our results suggest that although HIV infection duration may intensify trauma symptoms and deteriorate social support, perceived available social support may act as a buffer against HIV-related trauma symptoms.

A task-difficulty artifact in subliminal priming.

PubMed

Pratte, Michael S; Rouder, Jeffrey N

2009-08-01

Subliminal priming is said to occur when a subliminal prime influences the classification of a subsequent target. Most subliminal-priming claims are based on separate target- and prime-classification tasks. Because primes are intended to be subliminal, the prime-classification task is difficult, and the target-classification task is easy. To assess whether this task-difficulty difference accounts for previous claims of subliminal priming, we manipulated the ease of the prime-classification task by intermixing long-duration (visible) primes with short-duration (near liminal) ones. In Experiment 1, this strategy of intermixing long-duration primes raised classification of the short-duration ones. In Experiments 2 and 3, prime duration was lowered in such a way that prime classification was at chance in intermixed presentations. Under these conditions, we failed to observe any priming effects; hence, previous demonstrations of subliminal priming may simply have reflected a task-difficulty artifact.

Relationships among goal orientations, motivational climate and flow in adolescent athletes: differences by gender.

PubMed

Moreno Murcia, Juan Antonio; Cervelló Gimeno, Eduardo; González-Cutre Coll, David

2008-05-01

The purpose of this investigation was to examine the relationships among perceived motivational climate, individuals' goal orientations, and dispositional flow, with attention to possible gender differences. A sample of 413 young athletes, ages 12 to 16 years, completed the Perceived Motivational Climate in Sport Questionnaire-2 (PMCSQ-2) and Perception of Success Questionnaire (POSQ), as well as the Dispositional Flow Scale. Task orientation was positively and significantly related to a perceived task-involving motivational climate and to the disposition to experience flow in the sport. Ego orientation was positively and significantly associated with a perceived ego-involving motivational climate and with dispositional flow. The perceptions of task-involving and ego-involving motivational climates were positively and significantly linked to general dispositional flow. Multiple regression analysis indicated that both task and ego goal orientations and perceived task- and ego-oriented climates predicted dispositional flow. Males displayed a stronger ego orientation, and were more likely to report that they participated in an ego-oriented climate, than did females. To the contrary, the females were more likely to perceive a task-oriented climate than did the males. No meaningful differences were found between males and females in general dispositional flow.

Subconscious Visual Cues during Movement Execution Allow Correct Online Choice Reactions

PubMed Central

Leukel, Christian; Lundbye-Jensen, Jesper; Christensen, Mark Schram; Gollhofer, Albert; Nielsen, Jens Bo; Taube, Wolfgang

2012-01-01

Part of the sensory information is processed by our central nervous system without conscious perception. Subconscious processing has been shown to be capable of triggering motor reactions. In the present study, we asked the question whether visual information, which is not consciously perceived, could influence decision-making in a choice reaction task. Ten healthy subjects (28±5 years) executed two different experimental protocols. In the Motor reaction protocol, a visual target cue was shown on a computer screen. Depending on the displayed cue, subjects had to either complete a reaching movement (go-condition) or had to abort the movement (stop-condition). The cue was presented with different display durations (20–160 ms). In the second Verbalization protocol, subjects verbalized what they experienced on the screen. Again, the cue was presented with different display durations. This second protocol tested for conscious perception of the visual cue. The results of this study show that subjects achieved significantly more correct responses in the Motor reaction protocol than in the Verbalization protocol. This difference was only observed at the very short display durations of the visual cue. Since correct responses in the Verbalization protocol required conscious perception of the visual information, our findings imply that the subjects performed correct motor responses to visual cues, which they were not conscious about. It is therefore concluded that humans may reach decisions based on subconscious visual information in a choice reaction task. PMID:23049749

Deciding what to see: the role of intention and attention in the perception of apparent motion.

PubMed

Kohler, Axel; Haddad, Leila; Singer, Wolf; Muckli, Lars

2008-03-01

Apparent motion is an illusory perception of movement that can be induced by alternating presentations of static objects. Already in Wertheimer's early investigation of the phenomenon [Wertheimer, M. (1912). Experimentelle Studien über das Sehen von Bewegung. Zeitschrift fur Psychologie, 61, 161-265], he mentions that voluntary attention can influence the way in which an ambiguous apparent motion display is perceived. But until now, few studies have investigated how strong the modulation of apparent motion through attention can be under different stimulus and task conditions. We used bistable motion quartets of two different sizes, where the perception of vertical and horizontal motion is equally likely. Eleven observers participated in two experiments. In Experiment 1, participants were instructed to either (a) hold the current movement direction as long as possible, (b) passively view the stimulus, or (c) switch the movement directions as quickly as possible. With the respective instructions, observers could almost double phase durations in (a) and more than halve durations in (c) relative to the passive condition. This modulation effect was stronger for the large quartets. In Experiment 2, observers' attention was diverted from the stimulus by a detection task at fixation while they still had to report their conscious perception. This manipulation prolonged dominance durations for up to 100%. The experiments reveal a high susceptibility of ambiguous apparent motion to attentional modulation. We discuss how feature- and space-based attention mechanisms might contribute to those effects.

Inhibition of return shortens perceived duration of a brief visual event.

PubMed

Osugi, Takayuki; Takeda, Yuji; Murakami, Ikuya

2016-11-01

We investigated the influence of attentional inhibition on the perceived duration of a brief visual event. Although attentional capture by an exogenous cue is known to prolong the perceived duration of an attended visual event, it remains unclear whether time perception is also affected by subsequent attentional inhibition at the location previously cued by an exogenous cue, an attentional phenomenon known as inhibition of return. In this study, we combined spatial cuing and duration judgment. After one second from the appearance of an uninformative peripheral cue either to the left or to the right, a target appeared at a cued side in one-third of the trials, which indeed yielded inhibition of return, and at the opposite side in another one-third of the trials. In the remaining trials, a cue appeared at a central box and one second later, a target appeared at either the left or right side. The target at the previously cued location was perceived to last shorter than the target presented at the opposite location, and shorter than the target presented after the central cue presentation. Therefore, attentional inhibition produced by a classical paradigm of inhibition of return decreased the perceived duration of a brief visual event. Copyright © 2016 Elsevier Ltd. All rights reserved.

Assessment of an active industrial exoskeleton to aid dynamic lifting and lowering manual handling tasks.

PubMed

Huysamen, Kirsten; de Looze, Michiel; Bosch, Tim; Ortiz, Jesus; Toxiri, Stefano; O'Sullivan, Leonard W

2018-04-01

The aim of this study was to evaluate the effect of an industrial exoskeleton on muscle activity, perceived musculoskeletal effort, measured and perceived contact pressure at the trunk, thighs and shoulders, and subjective usability for simple sagittal plane lifting and lowering conditions. Twelve male participants lifted and lowered a box of 7.5 kg and 15 kg, respectively, from mid-shin height to waist height, five times, both with and without the exoskeleton. The device significantly reduced muscle activity of the Erector Spinae (12%-15%) and Biceps Femoris (5%). Ratings of perceived musculoskeletal effort in the trunk region were significantly less with the device (9.5%-11.4%). The measured contact pressure was highest on the trunk (91.7 kPa-93.8 kPa) and least on shoulders (47.6 kPa-51.7 kPa), whereas pressure was perceived highest on the thighs (35-44% of Max LPP). Six of the users rated the device usability as acceptable. The exoskeleton reduced musculoskeletal loading on the lower back and assisted with hip extensor torque during lifting and lowering. Contact pressures fell below the Pain Pressure Threshold. Perceived pressure was not exceptionally high, but sufficiently high to cause discomfort if used for long durations. Copyright © 2017 Elsevier Ltd. All rights reserved.

The effects of task difficulty on visual search strategy in virtual 3D displays.

PubMed

Pomplun, Marc; Garaas, Tyler W; Carrasco, Marisa

2013-08-28

Analyzing the factors that determine our choice of visual search strategy may shed light on visual behavior in everyday situations. Previous results suggest that increasing task difficulty leads to more systematic search paths. Here we analyze observers' eye movements in an "easy" conjunction search task and a "difficult" shape search task to study visual search strategies in stereoscopic search displays with virtual depth induced by binocular disparity. Standard eye-movement variables, such as fixation duration and initial saccade latency, as well as new measures proposed here, such as saccadic step size, relative saccadic selectivity, and x-y target distance, revealed systematic effects on search dynamics in the horizontal-vertical plane throughout the search process. We found that in the "easy" task, observers start with the processing of display items in the display center immediately after stimulus onset and subsequently move their gaze outwards, guided by extrafoveally perceived stimulus color. In contrast, the "difficult" task induced an initial gaze shift to the upper-left display corner, followed by a systematic left-right and top-down search process. The only consistent depth effect was a trend of initial saccades in the easy task with smallest displays to the items closest to the observer. The results demonstrate the utility of eye-movement analysis for understanding search strategies and provide a first step toward studying search strategies in actual 3D scenarios.

A survey of nurses' perceived competence and educational needs in performing resuscitation.

PubMed

Roh, Young Sook; Issenberg, S Barry; Chung, Hyun Soo; Kim, So Sun; Lim, Tae Ho

2013-05-01

Effective training is needed for high-quality performance of staff nurses, who are often the first responders in initiating resuscitation. There is insufficient evidence to identify specific educational strategies that improve outcomes, including early recognition and rescue of the critical patient. This study was conducted to identify perceived competence and educational needs as well as to examine factors influencing perceived competence in resuscitation among staff nurses to build a resuscitation training curriculum. A convenience sample of 502 staff nurses was recruited from 11 hospitals in a single city. Staff nurses were asked to complete a self-administered questionnaire. On a five-point scale, chest compression was the lowest-rated technical skill (M = 3.33, SD = 0.80), whereas staying calm and focusing on required tasks was the lowest-rated non-technical skill (M = 3.30, SD = 0.80). Work duration, the usefulness of simulation, recent code experience, and recent simulation-based training were significant factors in perceived competence, F(4, 496) = 45.94, p < .001. Simulation-based resuscitation training was the most preferred training modality, and cardiac arrest was the most preferred training topic. Based on this needs assessment, a simulation-based resuscitation training curriculum with cardiac arrest scenarios is suggested to improve the resuscitation skills of staff nurses. Copyright 2013, SLACK Incorporated.

Mental workload measurement for emergency operating procedures in digital nuclear power plants.

PubMed

Gao, Qin; Wang, Yang; Song, Fei; Li, Zhizhong; Dong, Xiaolu

2013-01-01

Mental workload is a major consideration for the design of emergency operation procedures (EOPs) in nuclear power plants. Continuous and objective measures are desired. This paper compares seven mental workload measurement methods (pupil size, blink rate, blink duration, heart rate variability, parasympathetic/sympathetic ratio, total power and (Goals, Operations, Methods, and Section Rules)-(Keystroke Level Model) GOMS-KLM-based workload index) with regard to sensitivity, validity and intrusiveness. Eighteen participants performed two computerised EOPs of different complexity levels, and mental workload measures were collected during the experiment. The results show that the blink rate is sensitive to both the difference in the overall task complexity and changes in peak complexity within EOPs, that the error rate is sensitive to the level of arousal and correlate to the step error rate and that blink duration increases over the task period in both low and high complexity EOPs. Cardiac measures were able to distinguish tasks with different overall complexity. The intrusiveness of the physiological instruments is acceptable. Finally, the six physiological measures were integrated using group method of data handling to predict perceived overall mental workload. The study compared seven measures for evaluating the mental workload with emergency operation procedure in nuclear power plants. An experiment with simulated procedures was carried out, and the results show that eye response measures are useful for assessing temporal changes of workload whereas cardiac measures are useful for evaluating the overall workload.

The effectiveness of robotic training depends on motor task characteristics.

PubMed

Marchal-Crespo, Laura; Rappo, Nicole; Riener, Robert

2017-12-01

Previous research suggests that the effectiveness of robotic training depends on the motor task to be learned. However, it is still an open question which specific task's characteristics influence the efficacy of error-modulating training strategies. Motor tasks can be classified based on the time characteristics of the task, in particular the task's duration (discrete vs. continuous). Continuous tasks require movements without distinct beginning or end. Discrete tasks require fast movements that include well-defined postures at the beginning and the end. We developed two games, one that requires a continuous movement-a tracking task-and one that requires discrete movements-a fast reaching task. We conducted an experiment with thirty healthy subjects to evaluate the effectiveness of three error-modulating training strategies-no guidance, error amplification (i.e., repulsive forces proportional to errors) and haptic guidance-on self-reported motivation and learning of the continuous and discrete games. Training with error amplification resulted in better motor learning than haptic guidance, besides the fact that error amplification reduced subjects' interest/enjoyment and perceived competence during training. Only subjects trained with error amplification improved their performance after training the discrete game. In fact, subjects trained without guidance improved the performance in the continuous game significantly more than in the discrete game, probably because the continuous task required greater attentional levels. Error-amplifying training strategies have a great potential to provoke better motor learning in continuous and discrete tasks. However, their long-lasting negative effects on motivation might limit their applicability in intense neurorehabilitation programs.

Social cognition in anorexia nervosa: evidence of preserved theory of mind and impaired emotional functioning.

PubMed

Adenzato, Mauro; Todisco, Patrizia; Ardito, Rita B

2012-01-01

The findings of the few studies that have to date investigated the way in which individuals with Anorexia Nervosa (AN) navigate their social environment are somewhat contradictory. We undertook this study to shed new light on the social-cognitive profile of patients with AN, analysing Theory of Mind and emotional functioning. Starting from previous evidence on the role of the amygdala in the neurobiology of AN and in the social cognition, we hypothesise preserved Theory of Mind and impaired emotional functioning in patients with AN. Thirty women diagnosed with AN and thirty-two women matched for education and age were involved in the study. Theory of Mind and emotional functioning were assessed with a set of validated experimental tasks. A measure of perceived social support was also used to test the correlations between this dimension and the social-cognitive profile of AN patients. The performance of patients with AN is significantly worse than that of healthy controls on tasks assessing emotional functioning, whereas patients' performance is comparable to that of healthy controls on the Theory of Mind task. Correlation analyses showed no relationship between scores on any of the social-cognition tasks and either age of onset or duration of illness. A correlation between social support and emotional functioning was found. This latter result seems to suggest a potential role of social support in the treatment and recovery of AN. The pattern of results followed the experimental hypothesis. They may be useful to help us better understand the social-cognitive profile of patients with AN and to contribute to the development of effective interventions based on the ways in which patients with AN actually perceive their social environment.

The use of subjective rating of exertion in Ergonomics.

PubMed

Capodaglio, P

2002-01-01

In Ergonomics, the use of psychophysical methods for subjectively evaluating work tasks and determining acceptable loads has become more common. Daily activities at the work site are studied not only with physiological methods but also with perceptual estimation and production methods. The psychophysical methods are of special interest in field studies of short-term work tasks for which valid physiological measurements are difficult to obtain. The perceived exertion, difficulty and fatigue that a person experiences in a certain work situation is an important sign of a real or objective load. Measurement of the physical load with physiological parameters is not sufficient since it does not take into consideration the particular difficulty of the performance or the capacity of the individual. It is often difficult from technical and biomechanical analyses to understand the seriousness of a difficulty that a person experiences. Physiological determinations give important information, but they may be insufficient due to the technical problems in obtaining relevant but simple measurements for short-term activities or activities involving special movement patterns. Perceptual estimations using Borg's scales give important information because the severity of a task's difficulty depends on the individual doing the work. Observation is the most simple and used means to assess job demands. Other evaluations integrating observation are the followings: indirect estimation of energy expenditure based on prediction equations or direct measurement of oxygen consumption; measurements of forces, angles and biomechanical parameters; measurements of physiological and neurophysiological parameters during tasks. It is recommended that determinations of performances of occupational activities assess rating of perceived exertion and integrate these measurements of intensity levels with those of activity's type, duration and frequency. A better estimate of the degree of physical activity of individuals thus can be obtained.

Evaluative Processing of Food Images: A Conditional Role for Viewing in Preference Formation

PubMed Central

Wolf, Alexandra; Ounjai, Kajornvut; Takahashi, Muneyoshi; Kobayashi, Shunsuke; Matsuda, Tetsuya; Lauwereyns, Johan

2018-01-01

Previous research suggested a role of gaze in preference formation, not merely as an expression of preference, but also as a causal influence. According to the gaze cascade hypothesis, the longer subjects look at an item, the more likely they are to develop a preference for it. However, to date the connection between viewing and liking has been investigated predominately with self-paced viewing conditions in which the subjects were required to select certain items from simultaneously presented stimuli on the basis of perceived visual attractiveness. Such conditions might promote a default, but non-mandatory connection between viewing and liking. To explore whether the connection is separable, we examined the evaluative processing of single naturalistic food images in a 2 × 2 design, conducted completely within subjects, in which we varied both the type of exposure (self-paced versus time-controlled) and the type of evaluation (non-exclusive versus exclusive). In the self-paced exclusive evaluation, longer viewing was associated with a higher likelihood of a positive evaluation. However, in the self-paced non-exclusive evaluation, the trend reversed such that longer viewing durations were associated with lesser ratings. Furthermore, in the time-controlled tasks, both with non-exclusive and exclusive evaluation, there was no significant relationship between the viewing duration and the evaluation. The overall pattern of results was consistent for viewing times measured in terms of exposure duration (i.e., the duration of stimulus presentation on the screen) and in terms of actual gaze duration (i.e., the amount of time the subject effectively gazed at the stimulus on the screen). The data indicated that viewing does not intrinsically lead to a higher evaluation when evaluating single food images; instead, the relationship between viewing duration and evaluation depends on the type of task. We suggest that self-determination of exposure duration may be a prerequisite for any influence from viewing time on evaluative processing, regardless of whether the influence is facilitative. Moreover, the purported facilitative link between viewing and liking appears to be limited to exclusive evaluation, when only a restricted number of items can be included in a chosen set. PMID:29942273

Evaluative Processing of Food Images: A Conditional Role for Viewing in Preference Formation.

PubMed

Wolf, Alexandra; Ounjai, Kajornvut; Takahashi, Muneyoshi; Kobayashi, Shunsuke; Matsuda, Tetsuya; Lauwereyns, Johan

2018-01-01

Previous research suggested a role of gaze in preference formation, not merely as an expression of preference, but also as a causal influence. According to the gaze cascade hypothesis, the longer subjects look at an item, the more likely they are to develop a preference for it. However, to date the connection between viewing and liking has been investigated predominately with self-paced viewing conditions in which the subjects were required to select certain items from simultaneously presented stimuli on the basis of perceived visual attractiveness. Such conditions might promote a default, but non-mandatory connection between viewing and liking. To explore whether the connection is separable, we examined the evaluative processing of single naturalistic food images in a 2 × 2 design, conducted completely within subjects, in which we varied both the type of exposure (self-paced versus time-controlled) and the type of evaluation (non-exclusive versus exclusive). In the self-paced exclusive evaluation, longer viewing was associated with a higher likelihood of a positive evaluation. However, in the self-paced non-exclusive evaluation, the trend reversed such that longer viewing durations were associated with lesser ratings. Furthermore, in the time-controlled tasks, both with non-exclusive and exclusive evaluation, there was no significant relationship between the viewing duration and the evaluation. The overall pattern of results was consistent for viewing times measured in terms of exposure duration (i.e., the duration of stimulus presentation on the screen) and in terms of actual gaze duration (i.e., the amount of time the subject effectively gazed at the stimulus on the screen). The data indicated that viewing does not intrinsically lead to a higher evaluation when evaluating single food images; instead, the relationship between viewing duration and evaluation depends on the type of task. We suggest that self-determination of exposure duration may be a prerequisite for any influence from viewing time on evaluative processing, regardless of whether the influence is facilitative. Moreover, the purported facilitative link between viewing and liking appears to be limited to exclusive evaluation, when only a restricted number of items can be included in a chosen set.

Evidence for different processes involved in the effects of nontemporal stimulus size and numerical digit value on duration judgments.

PubMed

Rammsayer, Thomas H; Verner, Martin

2016-05-01

Perceived duration has been shown to be positively related to task-irrelevant, nontemporal stimulus magnitude. To account for this finding, Walsh's (2003) A Theory of Magnitude (ATOM) model suggests that magnitude of time is not differentiated from magnitude of other nontemporal stimulus characteristics and collectively processed by a generalized magnitude system. In Experiment 1, we investigated the combined effects of stimulus size and numerical quantity, as two nontemporal stimulus dimensions covered by the ATOM model, on duration judgments. Participants were required to reproduce the duration of target intervals marked by Arabic digits varying in physical size and numerical value. While the effect of stimulus size was effectively moderated by target duration, the effect of numerical value appeared to require attentional resources directed to the numerical value in order to become effective. Experiment 2 was designed to further elucidate the mediating influence of attention on the effect of numerical value on duration judgments. An effect of numerical value was only observed when participants' attention was directed to digit value, but not when participants were required to pay special attention to digit parity. While the ATOM model implies a common metrics and generalized magnitude processing for time, size, and quantity, the present findings provided converging evidence for the notion of two qualitatively different mechanisms underlying the effects of nontemporal stimulus size and numerical value on duration judgments. Furthermore, our data challenge the implicit common assumption that the effect of numerical value on duration judgments represents a continuously increasing function of digit magnitude.

Regularity and dimensional salience in temporal grouping.

PubMed

Prince, Jon B; Rice, Tim

2018-04-30

How do pitch and duration accents combine to influence the perceived grouping of musical sequences? Sequence context influences the relative importance of these accents; for example, the presence of learned structure in pitch exaggerates the effect of pitch accents at the expense of duration accents despite being irrelevant to the task and not attributable to attention (Prince, 2014b). In the current study, two experiments examined whether the presence of temporal structure has the opposite effect. Experiment 1 tested baseline conditions, in which participants (N = 30) heard sequences with various sizes of either pitch or duration accents, which implied either duple or triple groupings (accent every two or three notes, respectively). Sequences either had regular temporal structure (isochronous) or not (irregular, via using random interonset intervals). Regularity enhanced the effect of duration accents but had negligible influence on pitch accents. The accent sizes that gave the most equivalent ratings across dimension and regularity levels were used in Experiment 2 (N = 33), in which sequences contained both pitch and duration accents that suggested either duple, triple, or neutral groupings. Despite controlling for the baseline effect of regularity by selecting equally effective accent sizes, regularity had additional effects on duration accents, but only for duple groupings. Regularity did not influence the effectiveness of pitch accents when combined with duration accents. These findings offer some support for a dimensional salience hypothesis, which proposes that the presence of temporal structure should foster duration accent effectiveness at the expense of pitch accents. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Perceived Difficulty with Physical Tasks, Lifestyle, and Physical Performance in Obese Children

PubMed Central

D'Amico, Osvaldo; Sticco, Maura; Nugnes, Rosa; Mozzillo, Enza; Franzese, Adriana

2014-01-01

We estimated perceived difficulty with physical tasks, lifestyle, and physical performance in 382 children and adolescents (163 obese, 54 overweight, and 165 normal-weight subjects) and the relationship between perceived physical difficulties and sports participation, sedentary behaviors, or physical performance. Perceived difficulty with physical tasks and lifestyle habits was assessed by interview using a structured questionnaire, while physical performance was assessed through the six-minute walking test (6MWT). Obese children had higher perceived difficulty with several activities of daily living, were less engaged in sports, and had lower physical performance than normal-weight or overweight children; on the contrary, they did not differ with regard to time spent in sedentary behaviors. Perceived difficulty in running and hopping negatively predicted sports participation (P < 0.05 and <0.01, resp.), while perceived difficulty in almost all physical activities negatively predicted the 6MWT, independently of BMI (P < 0.01). Our results indicate that perception of task's difficulty level may reflect an actual difficulty in obese children. These findings may have practical implications for approaching physical activity in obese children. Exploring both the perception of a task's difficulty level and physical performance may be useful to design exercise programs that allow safe and successful participation. PMID:25105139

Visual attention mechanisms in happiness versus trustworthiness processing of facial expressions.

PubMed

Calvo, Manuel G; Krumhuber, Eva G; Fernández-Martín, Andrés

2018-03-01

A happy facial expression makes a person look (more) trustworthy. Do perceptions of happiness and trustworthiness rely on the same face regions and visual attention processes? In an eye-tracking study, eye movements and fixations were recorded while participants judged the un/happiness or the un/trustworthiness of dynamic facial expressions in which the eyes and/or the mouth unfolded from neutral to happy or vice versa. A smiling mouth and happy eyes enhanced perceived happiness and trustworthiness similarly, with a greater contribution of the smile relative to the eyes. This comparable judgement output for happiness and trustworthiness was reached through shared as well as distinct attentional mechanisms: (a) entry times and (b) initial fixation thresholds for each face region were equivalent for both judgements, thereby revealing the same attentional orienting in happiness and trustworthiness processing. However, (c) greater and (d) longer fixation density for the mouth region in the happiness task, and for the eye region in the trustworthiness task, demonstrated different selective attentional engagement. Relatedly, (e) mean fixation duration across face regions was longer in the trustworthiness task, thus showing increased attentional intensity or processing effort.

Mental and Physical Workload, Salivary Stress Biomarkers and Taste Perception: Mars Desert Research Station Expedition

PubMed Central

Rai, Balwant; Kaur, Jasdeep

2012-01-01

Background: Very few studies have been conducted on the effects of simulation of Mars conditions on taste. Aims: This study was planned to find the effects of physical and mental workload on taste sensitivity and salivary stress biomarkers. Materials and Methods: Twelve crew members were selected. Taste reactions and intensity of the taste sensations to quinine sulfate, citric acid, and sucrose were tested before and after mental and physical tasks for one hour. Also, psychological mood states by profile of mood state, salivary, salivary alpha amylase and cortisol, and current stress test scores were measured before and after mental and physical tasks. Results: Average time intensity evaluation showed that after the mental and physical tasks, the perceived duration of bitter, sour, and sweet taste sensations was significantly shortened relative to control group. There were good correlations between average time intensity of sweetness, bitterness, sourness and cortisol levels. Conclusions: Taste alterations due to stress can have an effect on the health and confidence of astronauts in long- term space missions. Thus, this issue remains one of the important issues for future human explorations. PMID:23181230

Does compliance to patient safety tasks improve and sustain when radiotherapy treatment processes are standardized?

PubMed

Simons, Pascale A M; Houben, Ruud; Benders, Jos; Pijls-Johannesma, Madelon; Vandijck, Dominique; Marneffe, Wim; Backes, Huub; Groothuis, Siebren

2014-10-01

To realize safe radiotherapy treatment, processes must be stabilized. Standard operating procedures (SOP's) were expected to stabilize the treatment process and perceived task importance would increase sustainability in compliance. This paper presents the effects on compliance to safety related tasks of a process redesign based on lean principles. Compliance to patient safety tasks was measured by video recording of actual radiation treatment, before (T0), directly after (T1) and 1.5 years after (T2) a process redesign. Additionally, technologists were surveyed on perceived task importance and reported incidents were collected for three half-year periods between 2007 and 2009. Compliance to four out of eleven tasks increased at T1, of which improvements on three sustained (T2). Perceived importance of tasks strongly correlated (0.82) to compliance rates at T2. The two tasks, perceived as least important, presented low base-line compliance, improved (T1), but relapsed at T2. The reported near misses (patient-level not reached) on accelerators increased (P < 0.001) from 144 (2007) to 535 (2009), while the reported misses (patient-level reached) remained constant. Compliance to specific tasks increased after introducing SOP's and improvements sustained after 1.5 years, indicating increased stability. Perceived importance of tasks correlated positively to compliance and sustainability. Raising the perception of task importance is thus crucial to increase compliance. The redesign resulted in increased willingness to report incidents, creating opportunities for patient safety improvement in radiotherapy treatment. Copyright © 2014 Elsevier Ltd. All rights reserved.

Sleep restriction during simulated wildfire suppression: effect on physical task performance.

PubMed

Vincent, Grace; Ferguson, Sally A; Tran, Jacqueline; Larsen, Brianna; Wolkow, Alexander; Aisbett, Brad

2015-01-01

To examine the effects of sleep restriction on firefighters' physical task performance during simulated wildfire suppression. Thirty-five firefighters were matched and randomly allocated to either a control condition (8-hour sleep opportunity, n = 18) or a sleep restricted condition (4-hour sleep opportunity, n = 17). Performance on physical work tasks was evaluated across three days. In addition, heart rate, core temperature, and worker activity were measured continuously. Rate of perceived and exertion and effort sensation were evaluated during the physical work periods. There were no differences between the sleep-restricted and control groups in firefighters' task performance, heart rate, core temperature, or perceptual responses during self-paced simulated firefighting work tasks. However, the sleep-restricted group were less active during periods of non-physical work compared to the control group. Under self-paced work conditions, 4 h of sleep restriction did not adversely affect firefighters' performance on physical work tasks. However, the sleep-restricted group were less physically active throughout the simulation. This may indicate that sleep-restricted participants adapted their behaviour to conserve effort during rest periods, to subsequently ensure they were able to maintain performance during the firefighter work tasks. This work contributes new knowledge to inform fire agencies of firefighters' operational capabilities when their sleep is restricted during multi-day wildfire events. The work also highlights the need for further research to explore how sleep restriction affects physical performance during tasks of varying duration, intensity, and complexity.

Sleep Restriction during Simulated Wildfire Suppression: Effect on Physical Task Performance

PubMed Central

Vincent, Grace; Ferguson, Sally A.; Tran, Jacqueline; Larsen, Brianna; Wolkow, Alexander; Aisbett, Brad

2015-01-01

Objectives To examine the effects of sleep restriction on firefighters’ physical task performance during simulated wildfire suppression. Methods Thirty-five firefighters were matched and randomly allocated to either a control condition (8-hour sleep opportunity, n = 18) or a sleep restricted condition (4-hour sleep opportunity, n = 17). Performance on physical work tasks was evaluated across three days. In addition, heart rate, core temperature, and worker activity were measured continuously. Rate of perceived and exertion and effort sensation were evaluated during the physical work periods. Results There were no differences between the sleep-restricted and control groups in firefighters’ task performance, heart rate, core temperature, or perceptual responses during self-paced simulated firefighting work tasks. However, the sleep-restricted group were less active during periods of non-physical work compared to the control group. Conclusions Under self-paced work conditions, 4 h of sleep restriction did not adversely affect firefighters’ performance on physical work tasks. However, the sleep-restricted group were less physically active throughout the simulation. This may indicate that sleep-restricted participants adapted their behaviour to conserve effort during rest periods, to subsequently ensure they were able to maintain performance during the firefighter work tasks. This work contributes new knowledge to inform fire agencies of firefighters’ operational capabilities when their sleep is restricted during multi-day wildfire events. The work also highlights the need for further research to explore how sleep restriction affects physical performance during tasks of varying duration, intensity, and complexity. PMID:25615988

[Ocra Method: development of a new procedure for analysis of multiple tasks subject to infrequent rotation].

PubMed

Occhipinti, E; Colombini, Daniela; Occhipinti, M

2008-01-01

In the Ocra methods (Ocra index and Ocra Checklist), when computing the final indices (Ocra index or checklist score), in the case of more than one repetitive task a "traditional" procedure was already proposed, the results of which could be defined as "time-weighted average". This approach appears to be appropriate when considering rotations among tasks that are performed very frequently, for instance almost once every hour (or for shorter periods). However, when rotation among repetitive tasks is less frequent (i.e. once every 1 1/2 or more hours), the "time-weighted average" approach could result in an underestimation of the exposure level (as it practically flattens peaks of high exposures). For those scenarios an alternative approach based on the "most stressful task as minimum" might be more realistic. This latter approach has already been included in the NIOSH approach for multiple sequential lifting tasks and, given the recent availability in the Ocra method of more detailed duration multipliers (practically one different Du(M) for each different step of one hour of duration of the repetitive task), it is now possible to define a particular procedure to compute the complex Ocra Multitask Index (cOCRA) and the complex Checklist Score (cCHESCO) for the analysis of two or more repetitive tasks when rotations are infrequent (rotations every 1 1/2 hours or more). The result of this approach will be at least equal to the index of the most stressful task considered for its individual daily duration and at the most equal to the index of the most stressful task when it is (only theoretically) considered as lasting for the overall daily duration of all examined repetitive tasks. The procedure is based on the following formula: Complex Ocra Multitask Index = Ocra(1(Dum1) + (Delta ocra1xK) where 1,2,3,...,N = repetitive tasks ordered by ocra index values (1 = highest; N = lowest) computed considering respective real duration multipliers (Dum(i)). ocra1 = ocra index of task, considering Dum(1). Dum(i) = duration multiplier for task(i) real duration. Dum(tot) = duration multiplier for total duration of all repetitive tasks. delta ocra1 = highest ocra index among N tasks considering Dum(tot) (ocra(i max)) - ocra index of task1 considering Dum1. K = (ocra(1 max)*FT1) + (ocra(2 max)*FT2) + ... + (ocra (N)*FT(N)) over (ocra(i max)). ocral,Nm(1,N MAX) = index of tasks 1 to Ncons idering Dum,, (tot)7=Fr(i) c tion of Time (values from 0 to 1) of task; wi(i)h respect to the total repetitive time.

Perception and Reality of Cognitive Function: Information Processing Speed, Perceived Memory Function, and Perceived Task Difficulty in Older Adults.

PubMed

Torrens-Burton, Anna; Basoudan, Nasreen; Bayer, Antony J; Tales, Andrea

2017-01-01

This study examines the relationships between two measures of information processing speed associated with executive function (Trail Making Test and a computer-based visual search test), the perceived difficulty of the tasks, and perceived memory function (measured by the Memory Functioning Questionnaire) in older adults (aged 50+ y) with normal general health, cognition (Montreal Cognitive Assessment score of 26+), and mood. The participants were recruited from the community rather than through clinical services, and none had ever sought or received help from a health professional for a memory complaint or mental health problem. For both the trail making and the visual search tests, mean information processing speed was not correlated significantly with perceived memory function. Some individuals did, however, reveal substantially slower information processing speeds (outliers) that may have clinical significance and indicate those who may benefit most from further assessment and follow up. For the trail making, but not the visual search task, higher levels of subjective memory dysfunction were associated with a greater perception of task difficulty. The relationship between actual information processing speed and perceived task difficulty also varied with respect to the task used. These findings highlight the importance of taking into account the type of task and metacognition factors when examining the integrity of information processing speed in older adults, particularly as this measure is now specifically cited as a key cognitive subdomain within the diagnostic framework for neurocognitive disorders.

Perception and Reality of Cognitive Function: Information Processing Speed, Perceived Memory Function, and Perceived Task Difficulty in Older Adults

PubMed Central

Torrens-Burton, Anna; Basoudan, Nasreen; Bayer, Antony J.; Tales, Andrea

2017-01-01

This study examines the relationships between two measures of information processing speed associated with executive function (Trail Making Test and a computer-based visual search test), the perceived difficulty of the tasks, and perceived memory function (measured by the Memory Functioning Questionnaire) in older adults (aged 50+ y) with normal general health, cognition (Montreal Cognitive Assessment score of 26+), and mood. The participants were recruited from the community rather than through clinical services, and none had ever sought or received help from a health professional for a memory complaint or mental health problem. For both the trail making and the visual search tests, mean information processing speed was not correlated significantly with perceived memory function. Some individuals did, however, reveal substantially slower information processing speeds (outliers) that may have clinical significance and indicate those who may benefit most from further assessment and follow up. For the trail making, but not the visual search task, higher levels of subjective memory dysfunction were associated with a greater perception of task difficulty. The relationship between actual information processing speed and perceived task difficulty also varied with respect to the task used. These findings highlight the importance of taking into account the type of task and metacognition factors when examining the integrity of information processing speed in older adults, particularly as this measure is now specifically cited as a key cognitive subdomain within the diagnostic framework for neurocognitive disorders. PMID:28984584

The compression of perceived time in a hot environment depends on physiological and psychological factors.

PubMed

Tamm, Maria; Jakobson, Ainika; Havik, Merle; Burk, Andres; Timpmann, Saima; Allik, Jüri; Oöpik, Vahur; Kreegipuu, Kairi

2014-01-01

The human perception of time was observed under extremely hot conditions. Young healthy men performed a time production task repeatedly in 4 experimental trials in either a temperate (22 °C, relative humidity 35%) or a hot (42 °C, relative humidity 18%) environment and with or without a moderate-intensity treadmill exercise. Within 1 hour, the produced durations indicated a significant compression of short intervals (0.5 to 10 s) in the combination of exercising and high ambient temperature, while neither variable/condition alone was enough to yield the effect. Temporal judgement was analysed in relation to different indicators of arousal, such as critical flicker frequency (CFF), core temperature, heart rate, and subjective ratings of fatigue and exertion. The arousal-sensitive internal clock model (originally proposed by Treisman) is used to explain the temporal compression while exercising in heat. As a result, we suggest that the psychological response to heat stress, the more precisely perceived fatigue, is important in describing the relationship between core temperature and time perception. Temporal compression is related to higher core temperature, but only if a certain level of perceived fatigue is accounted for, implying the existence of a thermoemotional internal clock.

What would you do? The effect of verbal persuasion on task choice.

PubMed

Lamarche, Larkin; Gionfriddo, Alicia M; Cline, Lindsay E; Gammage, Kimberley L; Adkin, Allan L

2014-01-01

Verbal persuasion has been shown to influence psychological and behavioral outcomes. The present study had two objectives: (1) to examine the effect of verbal persuasion on task choice in a balance setting and (2) to evaluate the use of verbal persuasion as an approach to experimentally induce mismatches between perceived and actual balance. Healthy young adults (N=68) completed an 8-m tandem walk task without vision and then were randomly assigned to a feedback group (good, control, or poor), regardless of actual balance. Following the feedback, participants chose to perform the task in one of three conditions differing in level of challenge and also were required to perform the task under the same pre-feedback conditions. Balance efficacy and perceived stability were rated before and after each pre- and post-feedback task, respectively. Balance performance measures were also collected. Following the feedback, participants in the good group were more likely to choose the most challenging task while those in the poor group were more likely to choose the least challenging task. Following the feedback, all groups showed improved balance performance. However, balance efficacy and perceived stability increased for the good and control groups but balance efficacy decreased and perceived stability was unchanged for the poor group. Thus, these findings demonstrate that verbal persuasion can influence task choice and may be used as an approach to experimentally create mismatches between perceived and actual balance. Copyright © 2013 Elsevier B.V. All rights reserved.

When Task Conflict Becomes Personal

PubMed Central

Guenter, Hannes; van Emmerik, Hetty; Schreurs, Bert; Kuypers, Tom; van Iterson, Ad; Notelaers, Guy

2016-01-01

Although potentially beneficial, task conflict may threaten teams because it often leads to relationship conflict. Prior research has identified a set of interpersonal factors (e.g., team communication, team trust) that help attenuate this association. The purpose of this article is to provide an alternative perspective that focuses on the moderating role of performance-related factors (i.e., perceived team performance). Using social identity theory, we build a model that predicts how task conflict associates with growth in relationship conflict and how perceived team performance influences this association. We test a three-wave longitudinal model by means of random coefficient growth modeling, using data from 60 ongoing teams working in a health care organization. Results provide partial support for our hypotheses. Only when perceived team performance is low, do task conflicts relate with growth in relationship conflict. We conclude that perceived team performance seems to enable teams to uncouple task from relationship conflict. PMID:28190944

Adolescent-Perceived Parent and Teacher Overestimation of Mathematics Ability: Developmental Implications for Students' Mathematics Task Values

ERIC Educational Resources Information Center

Gniewosz, Burkhard; Watt, Helen M. G.

2017-01-01

This study examines whether and how student-perceived parents' and teachers' overestimation of students' own perceived mathematical ability can explain trajectories for adolescents' mathematical task values (intrinsic and utility) controlling for measured achievement, following expectancy-value and self-determination theories. Longitudinal data…

Perceived empty duration between sounds of different lengths: Possible relation with repetition and rhythmic grouping.

PubMed

Kuroda, Tsuyoshi; Tomimatsu, Erika; Grondin, Simon; Miyazaki, Makoto

2016-11-01

We investigated how perceived duration of empty time intervals would be modulated by the length of sounds marking those intervals. Three sounds were successively presented in Experiment 1. Each sound was short (S) or long (L), and the temporal position of the middle sound's onset was varied. The lengthening of each sound resulted in delayed perception of the onset; thus, the middle sound's onset had to be presented earlier in the SLS than in the LSL sequence so that participants perceived the three sounds as presented at equal interonset intervals. In Experiment 2, a short sound and a long sound were alternated repeatedly, and the relative duration of the SL interval to the LS interval was varied. This repeated sequence was perceived as consisting of equal interonset intervals when the onsets of all sounds were aligned at physically equal intervals. If the same onset delay as in the preceding experiment had occurred, participants should have perceived equality between the interonset intervals in the repeated sequence when the SL interval was physically shortened relative to the LS interval. The effects of sound length seemed to be canceled out when the presentation of intervals was repeated. Finally, the perceived duration of the interonset intervals in the repeated sequence was not influenced by whether the participant's native language was French or Japanese, or by how the repeated sequence was perceptually segmented into rhythmic groups.

Perceived control in rhesus monkeys (Macaca mulatta) - Enhanced video-task performance

NASA Technical Reports Server (NTRS)

Washburn, David A.; Hopkins, William D.; Rumbaugh, Duane M.

1991-01-01

This investigation was designed to determine whether perceived control effects found in humans extend to rhesus monkeys (Macaca mulatta) tested in a video-task format, using a computer-generated menu program, SELECT. Choosing one of the options in SELECT resulted in presentation of five trials of a corresponding task and subsequent return to the menu. In Experiments 1-3, the animals exhibited stable, meaningful response patterns in this task (i.e., they made choices). In Experiment 4, performance on tasks that were selected by the animals significantly exceeded performance on identical tasks when assigned by the experimenter under comparable conditions (e.g., time of day, order, variety). The reliable and significant advantage for performance on selected tasks, typically found in humans, suggests that rhesus monkeys were able to perceive the availability of choices.

Time flies faster under time pressure.

PubMed

Rattat, Anne-Claire; Matha, Pauline; Cegarra, Julien

2018-04-01

We examined the effects of time pressure on duration estimation in a verbal estimation task and a production task. In both temporal tasks, participants had to solve mazes in two conditions of time pressure (with or without), and with three different target durations (30 s, 60 s, and 90 s). In each trial of the verbal estimation task, participants had to estimate in conventional time units (minutes and seconds) the amount of time that had elapsed since they started to solve the maze. In the production task, they had to press a key while solving the maze when they thought that the trial's duration had reached a target value. Results showed that in both tasks, durations were judged longer with time pressure than without it. However, this temporal overestimation under time pressure did not increase with the length of the target duration. These results are discussed within the framework of scalar expectancy theory. Copyright © 2018 Elsevier B.V. All rights reserved.

Manually controlled human balancing using visual, vestibular and proprioceptive senses involves a common, low frequency neural process

PubMed Central

Lakie, Martin; Loram, Ian D

2006-01-01

Ten subjects balanced their own body or a mechanically equivalent unstable inverted pendulum by hand, through a compliant spring linkage. Their balancing process was always characterized by repeated small reciprocating hand movements. These bias adjustments were an observable sign of intermittent alterations in neural output. On average, the adjustments occurred at intervals of ∼400 ms. To generate appropriate stabilizing bias adjustments, sensory information about body or load movement is needed. Subjects used visual, vestibular or proprioceptive sensation alone and in combination to perform the tasks. We first ask, is the time between adjustments (bias duration) sensory specific? Vision is associated with slow responses. Other senses involved with balance are known to be faster. Our second question is; does bias duration depend on sensory abundance? An appropriate bias adjustment cannot occur until unplanned motion is unambiguously perceived (a sensory threshold). The addition of more sensory data should therefore expedite action, decreasing the mean bias adjustment duration. Statistical analysis showed that (1) the mean bias adjustment duration was remarkably independent of the sensory modality and (2) the addition of one or two sensory modalities made a small, but significant, decrease in the mean bias adjustment duration. Thus, a threshold effect can alter only a very minor part of the bias duration. The bias adjustment duration in manual balancing must reflect something more than visual sensation and perceptual thresholds; our suggestion is that it is a common central motor planning process. We predict that similar processes may be identified in the control of standing. PMID:16959857

Association between females' perceptions of college aerobic class motivational climates and their responses.

PubMed

Brown, Theresa C; Fry, Mary D

2013-01-01

The aim of this study was to examine the relationship between female college students' perceptions of the motivational climate in their aerobics classes to their adaptive exercise responses. Data were collected from university group exercise classes in spring 2008. The participants (N = 213) responded to a questionnaire measuring perceptions of the climate (i.e., caring, task-, and ego-involving), correlates of intrinsic motivation (i.e., interest/enjoyment, perceived competence, effort/importance, and tension/pressure), commitment to exercise, and reasons for exercising. Canonical correlation analyses revealed that participants who perceived a predominately caring, task-involving climate reported higher interest/enjoyment, perceived competence, effort/importance, and commitment to exercise, as well as lower tension/pressure. Further, those who perceived a high caring, task-involving, and low ego-involving climate were also more likely to report more health-related reasons for exercise versus appearance-focused reasons. Results suggested that important motivational benefits might exist when women perceive caring, task-involving climates in their aerobics class settings. Aerobics class instructors who intentionally create caring, task-involving climates may promote more adaptive motivational responses among their female participants.

Effects of Self-Esteem and Perceived Goal Difficulty on Goal Setting, Certainty, Task Performance, and Attributions.

ERIC Educational Resources Information Center

Tang, Thomas Li-Ping; Reynolds, David B.

1993-01-01

Fifty-two subjects competed on a task against themselves, a difficult competitor, and an easy competitor. Certainty, ability attribution, and task satisfaction for those with low self-esteem were affected by perceived goal difficulty but not for those with high self-esteem. Low self-esteem groups had lower goals, certainty, and task performance.…

Performing well in an evaluative situation: the roles of perceived competence and task-irrelevant interfering thoughts.

PubMed

Van Yperen, Nico W

2007-12-01

This research expands on previous research by arguing and demonstrating that high perceived competence buffers the detrimental effects of an evaluative situation. In Study 1 (n=75, 38.7% male), the situation (evaluative vs. non-evaluative) and perceived competence (high vs. low) were manipulated, whereas in Study 2 (n=42, 33.3% male), perceived competence relied on naturally occurring differences in perceived competence. The results of Study 1 indicate that people may underachieve in an evaluative situation. More importantly, in Study 2 it was demonstrated that such an evaluative situation had only a negative effect on test performance among individuals low in perceived competence. The occurrence of task-irrelevant interfering thoughts during task completion accounted for this inimical effect of an evaluative situation on test performance among these individuals.

The effect of voice quality and competing speakers in a passage comprehension task: perceived effort in relation to cognitive functioning and performance in children with normal hearing.

PubMed

von Lochow, Heike; Lyberg-Åhlander, Viveka; Sahlén, Birgitta; Kastberg, Tobias; Brännström, K Jonas

2018-04-01

The study investigates the effect of voice quality and competing speakers on perceived effort in a passage comprehension task in relation to cognitive functioning. In addition, it explores if perceived effort was related to performance. A total of 49 children (aged 7:03 to 12:02 years) with normal hearing participated. The children performed an auditory passage comprehension task presented with six different listening conditions consisting of a typical voice or a dysphonic voice presented in quiet, with one competing speaker, and with four competing speakers. After completing the task, they rated their perceived effort on a five-grade scale. The children also performed tasks measuring working memory capacity (WMC) and executive functioning. The results show that voice quality had no direct effect on perceived effort but the children's ratings of perceived effort were related to their executive functioning. A significant effect was seen for background listening condition indicating higher perceived effort for background listening conditions with competing speakers. The effects of background listening condition were mainly related to the children's WMC but also their executive functioning. It can be concluded that the individual susceptibility to the effect of the dysphonic voice is related to the child's executive functioning. The individual susceptibility to the presence of competing speakers is related to the child's WMC and executive functioning.

Automatic Online Motor Control Is Intact in Parkinson's Disease With and Without Perceptual Awareness.

PubMed

Merritt, Kate E; Seergobin, Ken N; Mendonça, Daniel A; Jenkins, Mary E; Goodale, Melvyn A; MacDonald, Penny A

2017-01-01

In the double-step paradigm, healthy human participants automatically correct reaching movements when targets are displaced. Motor deficits are prominent in Parkinson's disease (PD) patients. In the lone investigation of online motor correction in PD using the double-step task, a recent study found that PD patients performed unconscious adjustments appropriately but seemed impaired for consciously-perceived modifications. Conscious perception of target movement was achieved by linking displacement to movement onset. PD-related bradykinesia disproportionately prolonged preparatory phases for movements to original target locations for patients, potentially accounting for deficits. Eliminating this confound in a double-step task, we evaluated the effect of conscious awareness of trajectory change on online motor corrections in PD. On and off dopaminergic therapy, PD patients ( n = 14) and healthy controls ( n = 14) reached to peripheral visual targets that remained stationary or unexpectedly moved during an initial saccade. Saccade latencies in PD are comparable to controls'. Hence, target displacements occurred at equal times across groups. Target jump size affected conscious awareness, confirmed in an independent target displacement judgment task. Small jumps were subliminal, but large target displacements were consciously perceived. Contrary to the previous result, PD patients performed online motor corrections normally and automatically, irrespective of conscious perception. Patients evidenced equivalent movement durations for jump and stay trials, and trajectories for patients and controls were identical, irrespective of conscious perception. Dopaminergic therapy had no effect on performance. In summary, online motor control is intact in PD, unaffected by conscious perceptual awareness. The basal ganglia are not implicated in online corrective responses.

Automatic Online Motor Control Is Intact in Parkinson’s Disease With and Without Perceptual Awareness

PubMed Central

Seergobin, Ken N.; Mendonça, Daniel A.

2017-01-01

Abstract In the double-step paradigm, healthy human participants automatically correct reaching movements when targets are displaced. Motor deficits are prominent in Parkinson’s disease (PD) patients. In the lone investigation of online motor correction in PD using the double-step task, a recent study found that PD patients performed unconscious adjustments appropriately but seemed impaired for consciously-perceived modifications. Conscious perception of target movement was achieved by linking displacement to movement onset. PD-related bradykinesia disproportionately prolonged preparatory phases for movements to original target locations for patients, potentially accounting for deficits. Eliminating this confound in a double-step task, we evaluated the effect of conscious awareness of trajectory change on online motor corrections in PD. On and off dopaminergic therapy, PD patients (n = 14) and healthy controls (n = 14) reached to peripheral visual targets that remained stationary or unexpectedly moved during an initial saccade. Saccade latencies in PD are comparable to controls’. Hence, target displacements occurred at equal times across groups. Target jump size affected conscious awareness, confirmed in an independent target displacement judgment task. Small jumps were subliminal, but large target displacements were consciously perceived. Contrary to the previous result, PD patients performed online motor corrections normally and automatically, irrespective of conscious perception. Patients evidenced equivalent movement durations for jump and stay trials, and trajectories for patients and controls were identical, irrespective of conscious perception. Dopaminergic therapy had no effect on performance. In summary, online motor control is intact in PD, unaffected by conscious perceptual awareness. The basal ganglia are not implicated in online corrective responses. PMID:29085900

Memory for time distinguishes between perception and action.

PubMed

Bueti, Domenica; Walsh, Vincent

2010-01-01

Our experience of time is unlike that of other features of the sensory world such as colour, movement, touch, or sound because there is no unique receptor system through which it is received. However, since time can be perceived, remembered, estimated, and compared in a way analogous to other sensory experiences, it should perhaps be subject to some of the same architectures or principles that have advanced understanding in these other domains. By adapting a task designed to test visual memory within a perception/action framework we investigated whether memory for time is affected by the use to which temporal information is put. When remembering a visual or auditory duration for subsequent motor production, storage is biased by a delay of up to 8 s. When the same duration is remembered for subsequent perception, however, there is no such effect of delay on memory. The results suggest a distinction in temporal memory that parallels the perception/action dichotomy in vision.

The effects of task difficulty on visual search strategy in virtual 3D displays

PubMed Central

Pomplun, Marc; Garaas, Tyler W.; Carrasco, Marisa

2013-01-01

Analyzing the factors that determine our choice of visual search strategy may shed light on visual behavior in everyday situations. Previous results suggest that increasing task difficulty leads to more systematic search paths. Here we analyze observers' eye movements in an “easy” conjunction search task and a “difficult” shape search task to study visual search strategies in stereoscopic search displays with virtual depth induced by binocular disparity. Standard eye-movement variables, such as fixation duration and initial saccade latency, as well as new measures proposed here, such as saccadic step size, relative saccadic selectivity, and x−y target distance, revealed systematic effects on search dynamics in the horizontal-vertical plane throughout the search process. We found that in the “easy” task, observers start with the processing of display items in the display center immediately after stimulus onset and subsequently move their gaze outwards, guided by extrafoveally perceived stimulus color. In contrast, the “difficult” task induced an initial gaze shift to the upper-left display corner, followed by a systematic left-right and top-down search process. The only consistent depth effect was a trend of initial saccades in the easy task with smallest displays to the items closest to the observer. The results demonstrate the utility of eye-movement analysis for understanding search strategies and provide a first step toward studying search strategies in actual 3D scenarios. PMID:23986539

Perceived Discrimination and Mexican-Origin Young Adults' Sleep Duration and Variability: The Moderating Role of Cultural Orientations.

PubMed

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

2017-08-01

Perceived ethnic discrimination is central to the experiences of Latino young adults, yet we know little about the ways in which and the conditions under which ethnic discrimination relates to Latino young adults' sleep patterns. Using a sample of 246 Mexican-origin young adults (M age  = 21.11, SD = 1.54; 50 % female), the current study investigated the longitudinal links between perceived ethnic discrimination and both sleep duration and night-to-night variability in duration, while also examining the moderating roles of Anglo and Mexican orientations in the associations. The results revealed that perceived discrimination predicted greater sleep variability, and this link was not moderated by cultural orientations. The relation between perceived discrimination and hours of sleep, however, was moderated by Anglo and Mexican orientations. Individuals with high Anglo and Mexican orientations (bicultural) and those with only high Mexican orientations (enculturated), showed no association between discrimination and hours of sleep. Individuals with low Anglo and Mexican orientations (marginalized) displayed a positive association, whereas those with high Anglo and low Mexican orientations (acculturated) displayed a negative association. The results suggest that discrimination has long term effects on sleep variability of Mexican-origin young adults, regardless of cultural orientations; however, for sleep duration, bicultural and enculturated orientations are protective.

Keep Your Eyes on the Road: Young Driver Crash Risk Increases According to Duration of Distraction

PubMed Central

Simons-Morton, Bruce; Guo, Feng; Klauer, Sheila G; Ehsani, Johnathon P; Pradhan, Anuj K

2014-01-01

Purpose Secondary task engagement that distracts the driver is a contributing factor to motor vehicle crashes among adults. However, the association between eye glance duration and crash risk with novice teenage drivers has not been determined. Methods Vehicles of 42 newly-licensed teenage drivers were instrumented with cameras, accelerometers, GPS, and other devices. Data were collected continuously for 18 months. Crashes and near crashes (CNCs) were identified by examining highly elevated gravitational force events. Video footage of the 6 seconds prior to each CNC and randomly sampled non-CNC road segments were coded for the duration of eye glances off the forward roadway and the presence of secondary task engagement. The likelihood (odds ratios) of CNC due to eye glance behavior was calculated by comparing the prevalence of secondary task engagement and duration of eyes off road prior to CNC with the prevalence and duration of eyes off road during non-CNC road segments. Results Crash risk increased with the duration of single longest glance during all secondary tasks (OR=3.8 for >2s) and wireless secondary task engagement (OR=5.5 for >2s). Single longest glance provided a more consistent estimate of crash risk than total time eyes off the forward roadway. Conclusions Eyes glances away from forward roadway involving secondary tasks increased the likelihood of CNC. The longer the duration of eye glance away from the road the greater the risk, regardless of type of secondary task. Education and policy discouraging secondary task engagement, particularly for prolonged periods, is warranted. PMID:24759443

Motivational climate, goal orientation, perceived sport ability, and enjoyment within Finnish junior ice hockey players.

PubMed

Jaakkola, T; Ntoumanis, N; Liukkonen, J

2016-01-01

The aim of this study was to investigate the relations among situational motivational climate, dispositional approach and avoidance achievement goals, perceived sport ability, and enjoyment in Finnish male junior ice hockey players. The sample comprised 265 junior B-level male players with a mean age of 17.03 years (SD = 0.63). Players filled questionnaires tapping their perceptions of coach motivational climate, achievement goals, perceived sport ability, and enjoyment. For the statistical analysis, players were divided into high and low perceived sport ability groups. Multigroup structural equation modeling (SEM) revealed an indirect path from task-involving motivational climate via task-approach goal to enjoyment. Additionally, SEM demonstrated four other direct associations, which existed in both perceived ability groups: from ego-involving motivational climate to ego-approach and ego-avoidance goals; from ego-approach goal to ego-avoidance goal; and from task-avoidance goal to ego-avoidance goal. Additionally, in the high perceived sport ability group, there was an association from task-involving motivational climate to enjoyment. The results of this study reveal that motivational climate emphasizing effort, personal development and improvement, and achievement goal mastering tasks are significant elements of enjoyment in junior ice hockey. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

The Effect of Recovery Duration on Vastus Lateralis Oxygenation, Heart Rate, Perceived Exertion and Time Motion Descriptors during Small Sided Football Games.

PubMed

McLean, Scott; Kerhervé, Hugo; Lovell, Geoff P; Gorman, Adam D; Solomon, Colin

2016-01-01

Small sided games (SSG) of football are an effective and efficient format to simultaneously train the physiological, technical, and tactical components of football. The duration of the recovery period between bouts of SSG will affect the physiological response to subsequent bouts. It was hypothesised that decreasing the duration of recovery periods separating serial SSG bouts would increase physiological, and perceptual responses, and decrease high speed running, and distance during SSG bouts. Twelve experienced footballers (mean ± SD; age 21 ± 3 yrs; VO2peak 64 ± 7 ml·min·kg-1; playing experience 15 ± 3 yrs) completed two SSG sessions. Each SSG consisted of 3 vs. 3 players and 6 bouts of 2 min duration, with bouts separated by either 30 s recovery (REC-30) or 120 s recovery (REC-120). Deoxygenated haemoglobin (HHb) in the vastus lateralis (VL) (using near infrared spectroscopy), heart rate (HR) and time motion descriptors (TMD) (speed and distance) were measured continuously during the SSG sessions and perceived exertion (RPE) was measured for each bout. During the recovery periods, in REC-30 compared to REC-120, there was a significant (p < 0.05) main effect of a higher HHb and HR. During the bouts, in REC-30 compared to REC-120, there were no significant differences in HHb, HR, RPE, or TMD, but within both REC-30 and REC-120 there were significant increases as a function of bout number in RPE. Although a four-fold increase in recovery period allowed a significant increase in the recovery of HHb and HR, this did not increase the physiological, and perceptual responses, or time motion descriptors during the bouts. These results could have been due to the regulation of effort (pacing), in these experienced players performing an exercise task to which they were well adapted.

The Effect of Recovery Duration on Vastus Lateralis Oxygenation, Heart Rate, Perceived Exertion and Time Motion Descriptors during Small Sided Football Games

PubMed Central

McLean, Scott; Kerhervé, Hugo; Lovell, Geoff P.; Gorman, Adam D.; Solomon, Colin

2016-01-01

Purpose Small sided games (SSG) of football are an effective and efficient format to simultaneously train the physiological, technical, and tactical components of football. The duration of the recovery period between bouts of SSG will affect the physiological response to subsequent bouts. It was hypothesised that decreasing the duration of recovery periods separating serial SSG bouts would increase physiological, and perceptual responses, and decrease high speed running, and distance during SSG bouts. Methods Twelve experienced footballers (mean ± SD; age 21 ± 3 yrs; VO2peak 64 ± 7 ml·min·kg−1; playing experience 15 ± 3 yrs) completed two SSG sessions. Each SSG consisted of 3 vs. 3 players and 6 bouts of 2 min duration, with bouts separated by either 30 s recovery (REC-30) or 120 s recovery (REC-120). Deoxygenated haemoglobin (HHb) in the vastus lateralis (VL) (using near infrared spectroscopy), heart rate (HR) and time motion descriptors (TMD) (speed and distance) were measured continuously during the SSG sessions and perceived exertion (RPE) was measured for each bout. Results During the recovery periods, in REC-30 compared to REC-120, there was a significant (p < 0.05) main effect of a higher HHb and HR. During the bouts, in REC-30 compared to REC-120, there were no significant differences in HHb, HR, RPE, or TMD, but within both REC-30 and REC-120 there were significant increases as a function of bout number in RPE. Conclusions Although a four-fold increase in recovery period allowed a significant increase in the recovery of HHb and HR, this did not increase the physiological, and perceptual responses, or time motion descriptors during the bouts. These results could have been due to the regulation of effort (pacing), in these experienced players performing an exercise task to which they were well adapted. PMID:26919064

Who multi-tasks and why? Multi-tasking ability, perceived multi-tasking ability, impulsivity, and sensation seeking.

PubMed

Sanbonmatsu, David M; Strayer, David L; Medeiros-Ward, Nathan; Watson, Jason M

2013-01-01

The present study examined the relationship between personality and individual differences in multi-tasking ability. Participants enrolled at the University of Utah completed measures of multi-tasking activity, perceived multi-tasking ability, impulsivity, and sensation seeking. In addition, they performed the Operation Span in order to assess their executive control and actual multi-tasking ability. The findings indicate that the persons who are most capable of multi-tasking effectively are not the persons who are most likely to engage in multiple tasks simultaneously. To the contrary, multi-tasking activity as measured by the Media Multitasking Inventory and self-reported cell phone usage while driving were negatively correlated with actual multi-tasking ability. Multi-tasking was positively correlated with participants' perceived ability to multi-task ability which was found to be significantly inflated. Participants with a strong approach orientation and a weak avoidance orientation--high levels of impulsivity and sensation seeking--reported greater multi-tasking behavior. Finally, the findings suggest that people often engage in multi-tasking because they are less able to block out distractions and focus on a singular task. Participants with less executive control--low scorers on the Operation Span task and persons high in impulsivity--tended to report higher levels of multi-tasking activity.

Human performance on the temporal bisection task.

PubMed

Kopec, Charles D; Brody, Carlos D

2010-12-01

The perception and processing of temporal information are tasks the brain must continuously perform. These include measuring the duration of stimuli, storing duration information in memory, recalling such memories, and comparing two durations. How the brain accomplishes these tasks, however, is still open for debate. The temporal bisection task, which requires subjects to compare temporal stimuli to durations held in memory, is perfectly suited to address these questions. Here we perform a meta-analysis of human performance on the temporal bisection task collected from 148 experiments spread across 18 independent studies. With this expanded data set we are able to show that human performance on this task contains a number of significant peculiarities, which in total no single model yet proposed has been able to explain. Here we present a simple 2-step decision model that is capable of explaining all the idiosyncrasies seen in the data. Copyright © 2010 Elsevier Inc. All rights reserved.

Effects of gender role self-discrepancies and self-perceived attractiveness on social anxiety for women across social situations.

PubMed

Howell, Ashley N; Weeks, Justin W

2017-01-01

Psychosocial factors, such as gender role norms, may impact how social anxiety disorder (SAD) is experienced and expressed in different social contexts for women. However to date, these factors have not been examined via experimental methodology. This was a cross-sectional, quasi-experimental controlled study. The current study included 48 highly socially anxious (HSA) women (70.9% meeting criteria for SAD) and examined the relationships among psychosocial factors (i.e. gender role self-discrepancies and self-perceived physical attractiveness), self-perceived social performance, and state anxiety, across two in vivo social tasks (i.e. conversation and opinion speech). On average, participants reported belief that they ought to be less feminine for the speech task and more masculine for both the conversation and speech tasks. Also, for the conversation task, only lower self-rated attractiveness predicted poorer self-perceived performance and greater post-task state anxiety, above gender role self-discrepancies and confederate gender. For the speech task, only greater self-discrepancy in prototypical masculine traits predicted poorer performance ratings, and it was related to greater state anxiety in anticipation of the task. For HSA women, psychosocial factors may play different roles in social anxiety across social contexts.

Duration, distance, and speed judgments of two moving objects by 4- to 11-year olds.

PubMed

Matsuda, F

1996-11-01

Four- to 11-year-old children (N = 133) made duration, distance, and speed judgments on a Piagetian task where two cars ran on two parallel tracks. Special effort was made to make duration judgment tasks and distance judgment tasks comparable. Among younger children, difficulties of duration judgments and distance judgments were approximately the same. Additionally, temporal attributes had nearly the same effects on duration judgments as spatial attributes had on distance judgments, and spatial attributes had nearly the same effects on duration judgments as temporal attributes had on distance judgments. Among older children, distance judgments were easier than duration judgments, and the above-mentioned symmetry in effects of temporal and spatial attributes decreased somewhat. Temporal and spatial attributes affected speed judgments equally, across age groups.

The Limited Impact of Exposure Duration on Holistic Word Processing.

PubMed

Chen, Changming; Abbasi, Najam Ul Hasan; Song, Shuang; Chen, Jie; Li, Hong

2016-01-01

The current study explored the impact of stimuli exposure duration on holistic word processing measured by the complete composite paradigm (CPc paradigm). The participants were asked to match the cued target parts of two characters which were presented for either a long (600 ms) or a short duration (170 ms). They were also tested by two popular versions of the CPc paradigm: the "early-fixed" task where the attention cue was visible from the beginning of each trial at a fixed position, and the "delayed-random" task where the cue showed up after the study character at random locations. The holistic word effect, as indexed by the alignment × congruency interaction, was identified in both tasks and was unaffected by the stimuli duration in both tasks. Meanwhile, the "delayed-random" task did not bring about larger holistic word effect than the "early-fixed" task. These results suggest the exposure duration (from around 150 to 600 ms) has a limited impact on the holistic word effect, and have methodological implications for experiment designs in this field.

Skewed task conflicts in teams: What happens when a few members see more conflict than the rest?

PubMed

Sinha, Ruchi; Janardhanan, Niranjan S; Greer, Lindred L; Conlon, Donald E; Edwards, Jeffery R

2016-07-01

Task conflict has been the subject of a long-standing debate in the literature-when does task conflict help or hurt team performance? We propose that this debate can be resolved by taking a more precise view of how task conflicts are perceived in teams. Specifically, we propose that in teams, when a few team members perceive a high level of task disagreement while a majority of others perceive low levels of task disagreement-that is, there is positively skewed task conflict, task conflict is most likely to live up to its purported benefits for team performance. In our first study of student teams engaged in a business decision game, we find support for the positive relationship between skewed task conflict and team performance. In our second field study of teams in a financial corporation, we find that the relationship between positively skewed task conflict and supervisor ratings of team performance is mediated by reflective communication within the team. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

Inferior Frontal Gyrus Activation Underlies the Perception of Emotions, While Precuneus Activation Underlies the Feeling of Emotions during Music Listening.

PubMed

Tabei, Ken-ichi

2015-01-01

While music triggers many physiological and psychological reactions, the underlying neural basis of perceived and experienced emotions during music listening remains poorly understood. Therefore, using functional magnetic resonance imaging (fMRI), I conducted a comparative study of the different brain areas involved in perceiving and feeling emotions during music listening. I measured fMRI signals while participants assessed the emotional expression of music (perceived emotion) and their emotional responses to music (felt emotion). I found that cortical areas including the prefrontal, auditory, cingulate, and posterior parietal cortices were consistently activated by the perceived and felt emotional tasks. Moreover, activity in the inferior frontal gyrus increased more during the perceived emotion task than during a passive listening task. In addition, the precuneus showed greater activity during the felt emotion task than during a passive listening task. The findings reveal that the bilateral inferior frontal gyri and the precuneus are important areas for the perception of the emotional content of music as well as for the emotional response evoked in the listener. Furthermore, I propose that the precuneus, a brain region associated with self-representation, might be involved in assessing emotional responses.

The association of optimism and perceived discrimination with health care utilization in adults with sickle cell disease.

PubMed

Stanton, Michael V; Jonassaint, Charles R; Bartholomew, Frederick B; Edwards, Christopher; Richman, Laura; DeCastro, Laura; Williams, Redford

2010-11-01

We evaluated the effect of perceived discrimination, optimism, and their interaction on health care utilization among African American adults with sickle cell disease (SCD). Measures of optimism and perceived discrimination were obtained in 49 African American SCD patients. Multiple regression analyses controlling for sex and age tested effects of optimism and perceived discrimination on the number of emergency department visits (ED) and number and duration of hospitalizations over the past year. A perceived discrimination-optimism interaction was associated with number of emergency departments visits (b = .29, p = .052), number of hospitalizations (b = .36, p = .019), and duration of hospitalizations (b = .30, p = .045) such that those with high perceived discrimination/high optimism had the greatest health care utilization. African American SCD patients with high perceived discrimination/high optimism had greater health care utilization than patients who reported either low perceived discrimination or low optimism. This study suggests that patient personality and coping styles should be considered when evaluating the effects of stress on SCD-related outcomes.

Attention-based long-lasting sensitization and suppression of colors.

PubMed

Tseng, Chia-Huei; Vidnyanszky, Zoltan; Papathomas, Thomas; Sperling, George

2010-02-22

In contrast to the short-duration and quick reversibility of attention, a long-term sensitization to color based on protracted attention in a visual search task was reported by Tseng, Gobell, and Sperling (2004). When subjects were trained for a few hours to search for a red object among colored distracters, sensitivity to red was increased for weeks. This sensitization was quantified using ambiguous motion displays containing isoluminant red-green and texture-contrast gratings, in which the perceived motion-direction depended both on the attended color and on the relative red-green saturation. Such long-term effects could result from either sensitization of the attended color, or suppression of unattended colors, or a combination of the two. Here we unconfound these effects by eliminating one of the paired colors of the motion display from the search task. The other paired color in the motion display can then be either a target or a distracter in the search task. Thereby, we separately measure the effect of attention on sensitizing the target color or suppressing distracter colors. The results indicate that only sensitization of the target color in the search task is statistically significant for the present experimental conditions. We conclude that selective attention to a color in our visual search task caused long-term sensitization to the attended color but not significant long-term suppression of the unattended color. Copyright 2009 Elsevier Ltd. All rights reserved.

Perceived Difficulty of a Motor-Skill Task as a Function of Training.

ERIC Educational Resources Information Center

Bratfisch, Oswald; And Others

A simple device called a "wire labyrinth" was used in an experiment involving learning of a two-hand motor task. The Ss were asked, after completing each of 7 successive trails, to give their estimates of perceived (subjective) difficulty of the task. For this purpose, the psychophysical method of magnitude estimation was used. Time was…

Exploring Communication and Course Format: Conversation Frequency and Duration, Student Motives, and Perceived Teacher Approachability for Out-of-Class Contact

ERIC Educational Resources Information Center

Brooks, Catherine F.; Young, Stacy L.

2016-01-01

This study explored how course instructional format (i.e., online, face-to-face, or hybrid) is related to the frequency and duration of out-of-class communication (OCC) between college instructors and students, to student motives for communicating with teachers, and to perceived teacher approachability for conversation outside of class. Though…

Self-efficacy toward physical activity and the physical activity behavior of children with and without Developmental Coordination Disorder.

PubMed

Batey, C A; Missiuna, C A; Timmons, B W; Hay, J A; Faught, B E; Cairney, J

2014-08-01

Affecting 5-6% of children, Developmental Coordination Disorder (DCD) is a prevalent chronic condition. The nature of the disorder - impaired motor coordination - makes avoidance of physical activity (PA) common. The purpose of this study was to examine the effect of barrier and task self-efficacy on PA behavior in children with DCD and a group of typically developing (TD) children. Children were compared on their perceived ability to complete different intensities and duration of PA (task efficacy) and their confidence in completing PA when faced with everyday barriers (barrier efficacy). An accelerometer was used to record their activity over the subsequent week. Children with DCD were found to have significantly lower task efficacy and barrier efficacy. They also spent significantly less time in moderate to vigorous physical activity (MVPA). Multivariate analyses revealed that gender modified the relationship for both groups. Separate multivariate regressions, were therefore conducted by gender. A direct effect of DCD on PA was observed for boys, but not for girls. Further analyses showed that neither task efficacy nor barrier efficacy influenced the relationship between DCD and PA. Results from this study confirm that children with DCD have lower task and barrier self-efficacy than TD children and that males have lower PA levels than their TD peers; however neither task or barrier self-efficacy mediated the relationship between DCD and PA. Copyright © 2013. Published by Elsevier B.V.

Production practices affecting worker task demands in concrete operations: A case study.

PubMed

Memarian, Babak; Mitropoulos, Panagiotis

2015-01-01

Construction work involves significant physical, mental, and temporal task demands. Excessive task demands can have negative consequences for safety, errors and production. This exploratory study investigates the magnitude and sources of task demands on a concrete operation, and examines the effect of the production practices on the workers' task demands. The NASA Task Load Index was used to measure the perceived task demands of two work crews. The operation involved the construction of a cast-in-place concrete building under high schedule pressures. Interviews with each crew member were used to identify the main sources of the perceived demands. Extensive field observations and interviews with the supervisors and crews identified the production practices. The workers perceived different level of task demands depending on their role. The production practices influenced the task demands in two ways: (1) practices related to work organization, task design, resource management, and crew management mitigated the task demands; and (2) other practices related to work planning and crew management increased the crew's ability to cope with and adapt to high task demands. The findings identify production practices that regulate the workers' task demands. The effect of task demands on performance is mitigated by the ability to cope with high demands.

Elaborative rehearsal of nontemporal information interferes with temporal processing of durations in the range of seconds but not milliseconds.

PubMed

Rammsayer, Thomas; Ulrich, Rolf

2011-05-01

The distinct timing hypothesis suggests a sensory mechanism for processing of durations in the range of milliseconds and a cognitively controlled mechanism for processing of longer durations. To test this hypothesis, we employed a dual-task approach to investigate the effects of maintenance and elaborative rehearsal on temporal processing of brief and long durations. Unlike mere maintenance rehearsal, elaborative rehearsal as a secondary task involved transfer of information from working to long-term memory and elaboration of information to enhance storage in long-term memory. Duration discrimination of brief intervals was not affected by a secondary cognitive task that required either maintenance or elaborative rehearsal. Concurrent elaborative rehearsal, however, impaired discrimination of longer durations as compared to maintenance rehearsal and a control condition with no secondary task. These findings endorse the distinct timing hypothesis and are in line with the notion that executive functions, such as continuous memory updating and active transfer of information into long-term memory interfere with temporal processing of durations in the second, but not in the millisecond range. 2011 Elsevier B.V. All rights reserved.

Use of Multi-Intake Temporal Dominance of Sensations (TDS) to Evaluate the Influence of Cheese on Wine Perception.

PubMed

Galmarini, Mara V; Loiseau, Anne-Laure; Visalli, Michel; Schlich, Pascal

2016-10-01

Though the gastronomic sector recommends certain wine-cheese associations, there is little sensory evidence on how cheese influences the perception of wine. It was the aim of this study to dynamically characterize 4 wines as they would be perceived when consumed with and without cheese. The tasting protocol was based on multi-intake temporal dominance of sensations (TDS) coupled with hedonic rating. In the 1st session, 31 French wine and cheese consumers evaluated the wines (Pacherenc, Sancerre, Bourgogne, and Madiran) over 3 consecutive sips. In the following sessions, they performed the same task, but eating small portions of cheese (Epoisses, Comté, Roquefort, Crottin de Chavignol) between sips. All cheeses were tasted with all wines over 4 sessions. TDS data were mainly analyzed in terms of each attribute's duration of dominance by analysis of variance, multivariate analysis of variance, and canonical variate analysis. Results showed that cheese consumption had an impact (P < 0.1) on dominance duration of attributes and on preference for most wines. For example, in Madiran, all cheeses reduced dominance duration (P < 0.01) of astringency and sourness and increased duration of red fruit aroma. Although the number of consumers was small to make extended general conclusions on wine's preference, significant changes were observed before and after cheese intake. © 2016 Institute of Food Technologists®.

Impact of cardiac symptoms on self-reported household task performance in women with coronary artery disease.

PubMed

Kimble, L P

2001-01-01

Household tasks are highly salient physical activities for women. Inability to perform household tasks may serve as an important marker of limitations imposed by cardiac symptoms. The purpose of this study was to examine the impact of cardiac symptoms on perceived ability to perform household tasks in women with coronary artery disease and to examine relationships among age, whether the woman lived alone, ability to perform household tasks, and cardiac-related quality of life. Forty-one women with confirmed diagnosis of coronary artery disease and a mean age of 66 years (SD 12 years) were interviewed about the impact of their cardiac symptoms and perceived ability to perform household tasks (Household Activities Scale) and cardiac-related quality of life (Seattle Angina Questionnaire). The women were primarily white (89.4%) and retired (65.9%). Forty-six percent were married, and 26.8% lived alone. "Washing dishes" (51.3%) was the only task a majority of the sample could perform without limitation. Household tasks most commonly reported as no longer performed included carrying laundry (24.4%), vacuuming (30.0%), and scrubbing the floor (51.2%). The task most commonly modified because of cardiac symptoms was changing bed linens (60%). Of the 14 household tasks, women performed a mean of 3.39 (SD 3.36) activities without difficulty. Total number of household activities performed without difficulty was associated with better quality of life in the area of exertional capacity (r = 0.50, P = 0.001). Women who lived alone reported greater perceived ability to perform household tasks than women who did not live alone (r = 0.31, P = 0.05). Age was not significantly associated with perceived household task performance (r = -0.22, P = 0.17). Women with coronary artery disease (CAD) perceived cardiac symptoms as disrupting their ability to perform household tasks. Future research is needed to determine the independent impact of cardiac symptoms on functional limitations, especially in older women with heart disease, and whether changes in ability to perform household tasks could be a marker for coronary artery disease progression in women.

Negative, but not positive emotional images modulate the startle response independent of conscious awareness.

PubMed

Reagh, Zachariah M; Knight, David C

2013-08-01

The emotional response to a threat is influenced by the valence of other stimuli in the environment. This emotional modulation of the threat-elicited response occurs even when negative valence stimuli are not consciously perceived. Relatively little prior research has investigated whether nonconsciously perceived positive valence stimuli modify the response to a threat, and the work that has been completed is in need of additional rigorous testing of stimulus and valence perception. The current study presented images of negative, neutral, and positive valence (1,000 ms and 17 ms durations), followed by a mask. A startle probe (100 dB whitenoise) was presented during 33% of each trial type while eyeblink electromyography (EMG) and skin conductance response (SCR) were measured. During the study, participants rated the emotional content of each image to assess valence perception. Participants accurately classified the valence of 1,000 ms images, but not 17 ms images. Further, participants performed at chance levels on an independent postexperimental forced-choice perception task using 17 ms masked images, indicating they were unable to perceive the valence and content of these images. Greater EMG and SCR were elicited by the startle probe during perceived and unperceived negative images compared to perceived and unperceived positive and neutral images. In addition, perceived, but not unperceived positive images diminished startle responses. The current findings suggest that images of negative valence potentiate the startle response in the absence of conscious stimulus perception. However, the attenuation of the startle response by positive images appears to require perception of the emotional valence of an image. PsycINFO Database Record (c) 2013 APA, all rights reserved.

Perceived diabetes task competence mediates the relationship of both negative and positive affect with blood glucose in adolescents with type 1 diabetes.

PubMed

Fortenberry, Katherine T; Butler, Jorie M; Butner, Jonathan; Berg, Cynthia A; Upchurch, Renn; Wiebe, Deborah J

2009-02-01

Adolescents dealing with type 1 diabetes experience disruptions in affect and diabetes management that may influence their blood glucose. A daily diary format examined whether daily fluctuations in both negative and positive affect were associated with adolescents' perceived diabetes task competence (DTC) and blood glucose, and whether perceived DTC mediated the relationship between daily affect and blood glucose. Sixty-two adolescents with type 1 diabetes completed a 2-week daily diary, which included daily measures of affect and perceived DTC, then recorded their blood glucose readings at the end of the day. We utilized hierarchical linear modeling to examine whether daily perceived DTC mediated the relationship between daily emotion and blood glucose. Daily perceived DTC mediated the relationship of both negative and positive affect with daily blood glucose. This study suggests that within the ongoing process of self-regulation, daily affect may be associated with blood glucose by influencing adolescents' perception of competence on daily diabetes tasks.

Distortion in time perception as a result of concern about appearing biased

PubMed Central

Moskowitz, Gordon B.; Olcaysoy Okten, Irmak; Gooch, Cynthia M.

2017-01-01

Two experiments illustrate that the perception of a given time duration slows when white participants observe faces of black men, but only if participants are concerned with appearing biased. In Experiment 1 the concern with the appearance of bias is measured as a chronic state using the external motivation to respond without prejudice scale (Plant & Devine, 1998). In Experiment 2 it is manipulated by varying the race of the experimenter (black versus white). Time perception is assessed via a temporal discrimination task commonly used in the literature. Models of time perception identify arousal as a factor that causes perceived time to slow, and we speculate that arousal arising in intergroup interactions can alter time perception. PMID:28792515

A Study of Self and Task Performance in Childcare Centres as Perceived by Caregivers under Local Administrative Organisations in Thailand

ERIC Educational Resources Information Center

Bhulpat, Cheerapan

2011-01-01

The purpose of this research was to study the opinions toward self and task performance in childcare centres as perceived by caregivers under the jurisdiction of the Local Administrative Organization. The four areas evaluated were caregiver characteristics, task performance, objectives of caregiving and educating young children and problems and…

Defining the Focus of Attention: Effects of Attention on Perceived Exertion and Fatigue

PubMed Central

Lohse, Keith R.; Sherwood, David E.

2011-01-01

This manuscript presents two experiments designed to explore the effects of attention on perceived exertion and time to failure in a fatiguing athletic task. There were two major motivating factors for these experiments. First, there are few studies evaluating attentional focus effects in endurance tasks and, second, there is a lack of integration between studies of attentional focus as external/internal (e.g., Wulf, 2007a) compared to associative/dissociative (e.g., Stevinson and Biddle, 1998). In Experiment 1, we used a fatiguing wall-sit posture (essentially a complex, isometric task) to compare two different types of external attention with an internal focus on the position of the legs. An external focus (regardless of type) increased the time taken to failure and reduced perceived exertion. In Experiment 2, we manipulated subjects’ expectancy of fatigue to test the interaction of attention and expectancy (both top-down factors) in this highly fatiguing task. Previous theories of attention during endurance tasks have suggested that as fatigue/pain increase, bottom-up factors begin to dominate subjects’ attention. While this may be true, Experiment 2 showed that even in a highly fatiguing task, attentional strategies, and expectancies affected the time to failure and perceived exertion. PMID:22102843

Parental influences on students' self-concept, task value beliefs, and achievement in science.

PubMed

Senler, Burcu; Sungur, Semra

2009-05-01

The aim of this study was twofold: firstly, to investigate the grade level (elementary and middle school) and gender effect on students' motivation in science (perceived academic science self-concept and task value) and perceived family involvement, and secondly to examine the relationship among family environment variables (fathers' educational level, mothers' educational level, and perceived family involvement), motivation, gender and science achievement in elementary and middle schools. Multivariate Analysis of Variance (MANOVA) showed that elementary school students have more positive science self-concept and task value beliefs compared to middle school students. Moreover, elementary school students appeared to perceive more family involvement in their schooling. Path analyses also suggested that family involvement was directly linked to elementary school students' task value and achievement. Also, in elementary school level, significant relationships were found among father educational level, science self-concept, task value and science achievement. On the other hand, in middle school level, family involvement, father educational level, and mother educational level were positively related to students' task value which is directly linked to students' science achievement. Moreover, mother educational level contributed to science achievement through its effect on self-concept.

Personality Traits Moderate the Effect of Workload Sources on Perceived Workload in Flying Column Police Officers

PubMed Central

Chiorri, Carlo; Garbarino, Sergio; Bracco, Fabrizio; Magnavita, Nicola

2015-01-01

Previous research has suggested that personality traits of the Five Factor Model play a role in worker's response to workload. The aim of this study was to investigate the association of personality traits of first responders with their perceived workload in real-life tasks. A flying column of 269 police officers completed a measure of subjective workload (NASA-Task Load Index) after intervention tasks in a major public event. Officers' scores on a measure of Five Factor Model personality traits were obtained from archival data. Linear Mixed Modeling was used to test the direct and interaction effects of personality traits on workload scores once controlling for background variables, task type and workload source (mental, temporal and physical demand of the task, perceived effort, dissatisfaction for the performance and frustration due to the task). All personality traits except extraversion significantly interacted at least with one workload source. Perceived workload in flying column police officers appears to be the result of their personality characteristics interacting with the workload source. The implications of these results for the development of support measures aimed at reducing the impact of workload in this category of workers are discussed. PMID:26640456

Objective Cognitive Functioning in Self-reported Habitual Short Sleepers not Reporting Daytime Dysfunction: Examination of Impulsivity via Delay Discounting.

PubMed

Curtis, Brian J; Williams, Paula G; Anderson, Jeffrey S

2018-05-30

1) Examine performance on an objective measure of reward-related cognitive impulsivity (delay discounting) among self-reported habitual short sleepers and medium (i.e., recommended 7-9 hours) length sleepers either reporting or not reporting daytime dysfunction; 2) Inform the debate regarding what type and duration of short sleep (e.g., 21 to 24 hours of total sleep deprivation, self-reported habitual short sleep duration) meaningfully influences cognitive impulsivity; 3) Compare the predictive utility of sleep duration and perceived dysfunction to other factors previously shown to influence cognitive impulsivity via delay discounting performance (age, income, education, and fluid intelligence). We analyzed data from 1,190 adults from the Human Connectome Project database. Participants were grouped on whether they reported habitual short (≤ 6 hours) vs. medium length (7-9 hours) sleep duration and whether they perceived daytime dysfunction using the Pittsburgh Sleep Quality Index. All short sleepers exhibited increased delay discounting compared to all medium length sleepers, regardless of perceived dysfunction. Of the variables examined, self-reported sleep duration was the strongest predictor of delay discounting behavior between groups and across all 1,190 participants. Individuals who report habitual short sleep are likely to exhibit increased reward-related cognitive impulsivity regardless of perceived sleep-related daytime impairment. Therefore, there is reason to suspect that these individuals exhibit more daytime dysfunction, in the form of reward-related cognitive impulsivity, than they may assume. Current findings suggest that assessment of sleep duration over the prior month has meaningful predictive utility for human reward-related impulsivity.

Human auditory event-related potentials predict duration judgments.

PubMed

Bendixen, Alexandra; Grimm, Sabine; Schröger, Erich

2005-08-05

Internal clock models postulate a pulse accumulation process underlying timing activities, with more accumulated pulses resulting in longer perceived durations. We investigated whether this accumulation is reflected in the amplitude of event-related brain potentials (ERPs) elicited by auditory stimuli with durations of 400-600 ms. In a duration discrimination paradigm, we found more negative amplitudes to physically identical stimuli when they were judged as longer than the memorized standard duration (500 ms) as compared to being classified as shorter. This sustained negativity was already developing during the first 100 ms after stimulus onset. It could not be explained as a bias to respond with a particular hand (lateralized readiness potential), but rather reflects a processing difference between the tones to be judged as shorter or longer. Our results are in line with models of time processing which assume that higher numbers of accumulated pulses of a temporal processor result in an increase in perceived duration.

An investigation of the spatial selectivity of the duration after-effect.

PubMed

Maarseveen, Jim; Hogendoorn, Hinze; Verstraten, Frans A J; Paffen, Chris L E

2017-01-01

Adaptation to the duration of a visual stimulus causes the perceived duration of a subsequently presented stimulus with a slightly different duration to be skewed away from the adapted duration. This pattern of repulsion following adaptation is similar to that observed for other visual properties, such as orientation, and is considered evidence for the involvement of duration-selective mechanisms in duration encoding. Here, we investigated whether the encoding of duration - by duration-selective mechanisms - occurs early on in the visual processing hierarchy. To this end, we investigated the spatial specificity of the duration after-effect in two experiments. We measured the duration after-effect at adapter-test distances ranging between 0 and 15° of visual angle and for within- and between-hemifield presentations. We replicated the duration after-effect: the test stimulus was perceived to have a longer duration following adaptation to a shorter duration, and a shorter duration following adaptation to a longer duration. Importantly, this duration after-effect occurred at all measured distances, with no evidence for a decrease in the magnitude of the after-effect at larger distances or across hemifields. This shows that adaptation to duration does not result from adaptation occurring early on in the visual processing hierarchy. Instead, it seems likely that duration information is a high-level stimulus property that is encoded later on in the visual processing hierarchy. Copyright © 2016 Elsevier Ltd. All rights reserved.

Time estimation as a secondary task to measure workload. [attention sharing effect on operator performance

NASA Technical Reports Server (NTRS)

Hart, S. G.

1975-01-01

Variation in the length of time productions and verbal estimates of duration was investigated to determine the influence of concurrent activity on operator time perception. The length of 10-, 20-, and 30-sec intervals produced while performing six different compensatory tracking tasks was significantly longer, 23% on the average, than those produced while performing no other task. Verbal estimates of session duration, taken at the end of each of 27 experimental sessions, reflected a parallel increase in subjective underestimation of the passage of time as the difficulty of the task performed increased. These data suggest that estimates of duration made while performing a manual control task provide stable and sensitive measures of the workload imposed by the primary task, with minimal interference.

Age-related differences in processing visual device and task characteristics when using technical devices.

PubMed

Oehl, M; Sutter, C

2015-05-01

With aging visual feedback becomes increasingly relevant in action control. Consequently, visual device and task characteristics should more and more affect tool use. Focussing on late working age, the present study aims to investigate age-related differences in processing task irrelevant (display size) and task relevant visual information (task difficulty). Young and middle-aged participants (20-35 and 36-64 years of age, respectively) sat in front of a touch screen with differently sized active touch areas (4″ to 12″) and performed pointing tasks with differing task difficulties (1.8-5 bits). Both display size and age affected pointing performance, but the two variables did not interact and aiming duration moderated both effects. Furthermore, task difficulty affected the pointing durations of middle-aged adults moreso than those of young adults. Again, aiming duration accounted for the variance in the data. The onset of an age-related decline in aiming duration can be clearly located in middle adulthood. Thus, the fine psychomotor ability "aiming" is a moderator and predictor for age-related differences in pointing tasks. The results support a user-specific design for small technical devices with touch interfaces. Copyright © 2014 Elsevier Ltd and The Ergonomics Society. All rights reserved.

Correcting Memory Improves Accuracy of Predicted Task Duration

ERIC Educational Resources Information Center

Roy, Michael M.; Mitten, Scott T.; Christenfeld, Nicholas J. S.

2008-01-01

People are often inaccurate in predicting task duration. The memory bias explanation holds that this error is due to people having incorrect memories of how long previous tasks have taken, and these biased memories cause biased predictions. Therefore, the authors examined the effect on increasing predictive accuracy of correcting memory through…

Evaluating stereoscopic displays: both efficiency measures and perceived workload sensitive to manipulations in binocular disparity

NASA Astrophysics Data System (ADS)

van Beurden, Maurice H. P. H.; Ijsselsteijn, Wijnand A.; de Kort, Yvonne A. W.

2011-03-01

Stereoscopic displays are known to offer a number of key advantages in visualizing complex 3D structures or datasets. The large majority of studies that focus on evaluating stereoscopic displays for professional applications use completion time and/or the percentage of correct answers to measure potential performance advantages. However, completion time and accuracy may not fully reflect all the benefits of stereoscopic displays. In this paper, we argue that perceived workload is an additional valuable indicator reflecting the extent to which users can benefit from using stereoscopic displays. We performed an experiment in which participants were asked to perform a visual path-tracing task within a convoluted 3D wireframe structure, varying in level of complexity of the visualised structure and level of disparity of the visualisation. The results showed that an optimal performance (completion time, accuracy and workload), depend both on task difficulty and disparity level. Stereoscopic disparity revealed a faster and more accurate task performance, whereas we observed a trend that performance on difficult tasks stands to benefit more from higher levels of disparity than performance on easy tasks. Perceived workload (as measured using the NASA-TLX) showed a similar response pattern, providing evidence that perceived workload is sensitive to variations in disparity as well as task difficulty. This suggests that perceived workload could be a useful concept, in addition to standard performance indicators, in characterising and measuring human performance advantages when using stereoscopic displays.

The effects of environmental support and secondary tasks on visuospatial working memory.

PubMed

Lilienthal, Lindsey; Hale, Sandra; Myerson, Joel

2014-10-01

In the present experiments, we examined the effects of environmental support on participants' ability to rehearse locations and the role of such support in the effects of secondary tasks on memory span. In Experiment 1, the duration of interitem intervals and the presence of environmental support for visuospatial rehearsal (i.e., the array of possible memory locations) during the interitem intervals were both manipulated across four tasks. When support was provided, memory spans increased as the interitem interval durations increased, consistent with the hypothesis that environmental support facilitates rehearsal. In contrast, when environmental support was not provided, spans decreased as the duration of the interitem intervals increased, consistent with the hypothesis that visuospatial memory representations decay when rehearsal is impeded. In Experiment 2, the ratio of interitem interval duration to intertrial interval duration was kept the same on all four tasks, in order to hold temporal distinctiveness constant, yet forgetting was still observed in the absence of environmental support, consistent with the decay hypothesis. In Experiment 3, the effects of impeding rehearsal were compared to the effects of verbal and visuospatial secondary processing tasks. Forgetting of locations was greater when presentation of to-be-remembered locations alternated with the performance of a secondary task than when rehearsal was impeded by the absence of environmental support. The greatest forgetting occurred when a secondary task required the processing visuospatial information, suggesting that in addition to decay, both domain-specific and domain-general effects contribute to forgetting on visuospatial working memory tasks.

The Effects of Environmental Support and Secondary Tasks on Visuospatial Working Memory

PubMed Central

Lilienthal, Lindsey; Hale, Sandra; Myerson, Joel

2014-01-01

The present experiments examined the effects of environmental support on participants’ ability to rehearse locations and its role in the effects of secondary tasks on memory span. In Experiment 1, the duration of inter-item intervals and the presence of environmental support for visuospatial rehearsal (i.e., the array of possible memory locations) during the inter-item intervals were both manipulated across four tasks. When support was provided, memory spans increased as the inter-item interval durations increased, consistent with the hypothesis that environmental support facilitates rehearsal. In contrast, when environmental support was not provided, spans decreased as the duration of the inter-item intervals increased, consistent with the hypothesis that visuospatial memory representations decay when rehearsal is impeded. In Experiment 2, the ratio of inter-item interval duration to inter-trial interval duration was kept the same on all four tasks in order to hold temporal distinctiveness constant, yet forgetting was still observed in the absence of environmental support, consistent with the decay hypothesis. In Experiment 3, the effects of impeding rehearsal were compared to the effects of verbal and visuospatial secondary processing tasks. Forgetting of locations was greater when presentation of to-be-remembered locations alternated with performance of a secondary task than when rehearsal was impeded by the absence of environmental support. The greatest forgetting occurred when a secondary task required processing visuospatial information, suggesting that in addition to decay, both domain-specific and domain-general effects contribute to forgetting on visuospatial working memory tasks. PMID:24874509

Evaluation of restraint system concepts for the Japanese Experiment Module flight demonstration

NASA Technical Reports Server (NTRS)

Sampaio, Carlos E.; Fleming, Terence F.; Stuart, Mark A.; Backemeyer, Lynn A.

1995-01-01

The current International Space Station configuration includes a Japanese Experiment Module which relies on a large manipulator and a smaller dexterous manipulator to operate outside the pressurized environment of the experiment module. The module's flight demonstration is a payload that will be mounted in the aft flight deck on STS-87 to evaluate a prototype of the dexterous manipulator. Since the payload operations entail two 8-hour scenarios on consecutive days, adequate operator restraint at the workstation will be critical to the perceived success or failure of the payload. Simulations in reduced gravity environment on the KC-135A were the only way to evaluate the restraint systems and workstation configuration. Two astronaut and two non-astronaut operators evaluated the Advanced Lower Body Extremities Restraint Test and a foot loop restraint system by performing representative tasks at the workstation in each of the two restraint systems; at the end of each flight they gave their impressions of each system and the workstation. Results indicated that access to the workstation switch panels was difficult and manipulation of the hand controllers forced operators too low for optimal viewing of the aft flight deck monitors. The workstation panel should be angled for better visibility, and infrequently used switches should be on the aft flight deck panel. Pitch angle and placement of the hand controllers should optimize the operator's eye position with respect to the monitors. The lower body restraint was preferred over the foot loops because it allowed operators to maintain a more relaxed posture during long-duration tasks, its height adjustability allowed better viewing of aft flight deck monitors, and it provided better restraint for reacting forces imparted on the operator at the workstation. The foot loops provide adequate restraint for the flight demonstration tasks identified. Since results will impact the design of the workstation, both restraints should be flown and used during operation of the flight demonstration payload to evaluate the effect of restraint during long-duration tasks.

Predictive models to determine imagery strategies employed by children to judge hand laterality.

PubMed

Spruijt, Steffie; Jongsma, Marijtje L A; van der Kamp, John; Steenbergen, Bert

2015-01-01

A commonly used paradigm to study motor imagery is the hand laterality judgment task. The present study aimed to determine which strategies young children employ to successfully perform this task. Children of 5 to 8 years old (N = 92) judged laterality of back and palm view hand pictures in different rotation angles. Response accuracy and response duration were registered. Response durations of the trials with a correct judgment were fitted to a-priori defined predictive sinusoid models, representing different strategies to successfully perform the hand laterality judgment task. The first model predicted systematic changes in response duration as a function of rotation angle of the displayed hand. The second model predicted that response durations are affected by biomechanical constraints of hand rotation. If observed data could be best described by the first model, this would argue for a mental imagery strategy that does not involve motor processes to solve the task. The second model reflects a motor imagery strategy to solve the task. In line with previous research, we showed an age-related increase in response accuracy and decrease in response duration in children. Observed data for both back and palm view showed that motor imagery strategies were used to perform hand laterality judgments, but that not all the children use these strategies (appropriately) at all times. A direct comparison of response duration patterns across age sheds new light on age-related differences in the strategies employed to solve the task. Importantly, the employment of the motor imagery strategy for successful task performance did not change with age.

Time constraints in the alcohol purchase task.

PubMed

Kaplan, Brent A; Reed, Derek D; Murphy, James G; Henley, Amy J; Reed, Florence D DiGennaro; Roma, Peter G; Hursh, Steven R

2017-06-01

Hypothetical purchase tasks have advanced behavioral economic evaluations of demand by circumventing practical and ethical restrictions associated with delivering drug reinforcers to participants. Numerous studies examining the reliability and validity of purchase task methodology suggest that it is a valuable method for assessing demand that warrants continued use and evaluation. Within the literature examining purchase tasks, the alcohol purchase task (APT) has received the most investigation, and currently represents the most experimentally validated variant. However, inconsistencies in purchase task methodology between studies exist, even within APT studies, and, to date, none have assessed the influence of experimental economic constraints on responding. This study examined changes in Q0 (reported consumption when drinks are free), breakpoint (price that suppresses consumption), and α (rate of change in demand elasticity) in the presence of different hypothetical durations of access to alcohol in an APT. One hundred seventy-nine participants (94 males, 85 females) from Amazon Mechanical Turk completed 3 APTs that varied in the duration of time at a party (i.e., access to alcoholic beverages) as described in the APT instructions (i.e., vignette). The 3 durations included 5-hr (used by Murphy et al., 2013), 1-hr, and 9-hr time frames. We found that hypothetical duration of access was significantly related to Q0 and breakpoint at the individual level. Additionally, group-level mean α decreased significantly with increases in duration of access, thus indicating relatively higher demand for alcohol with longer durations of access. We discuss implications for conducting hypothetical purchase task research and alcohol misuse prevention efforts. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Obesity-related differences in neural correlates of force control.

PubMed

Mehta, Ranjana K; Shortz, Ashley E

2014-01-01

Greater body segment mass due to obesity has shown to impair gross and fine motor functions and reduce balance control. While recent studies suggest that obesity may be linked with altered brain functions involved in fine motor tasks, this association is not well investigated. The purpose of this study was to examine the neural correlates of motor performance in non-obese and obese adults during force control of two upper extremity muscles. Nine non-obese and eight obese young adults performed intermittent handgrip and elbow flexion exertions at 30% of their respective muscle strengths for 4 min. Functional near infrared spectroscopy was employed to measure neural activity in the prefrontal cortex bilaterally, joint steadiness was computed using force fluctuations, and ratings of perceived exertions (RPEs) were obtained to assess perceived effort. Obesity was associated with higher force fluctuations and lower prefrontal cortex activation during handgrip exertions, while RPE scores remained similar across both groups. No obesity-related differences in neural activity, force fluctuation, or RPE scores were observed during elbow flexion exertions. The study is one of the first to examine obesity-related differences on prefrontal cortex activation during force control of the upper extremity musculature. The study findings indicate that the neural correlates of motor activity in the obese may be muscle-specific. Future work is warranted to extend the investigation to monitoring multiple motor-function related cortical regions and examining obesity differences with different task parameters (e.g., longer duration, increased precision demands, larger muscles, etc.).

The association of subjective workload dimensions on quality of care and pharmacist quality of work life.

PubMed

Chui, Michelle A; Look, Kevin A; Mott, David A

2014-01-01

Workload has been described both objectively (e.g., number of prescriptions dispensed per pharmacist) as well as subjectively (e.g., pharmacist's perception of busyness). These approaches might be missing important characteristics of pharmacist workload that have not been previously identified and measured. To measure the association of community pharmacists' workload perceptions at three levels (organization, job, and task) with job satisfaction, burnout, and perceived performance of two tasks in the medication dispensing process. A secondary data analysis was performed using cross-sectional survey data collected from Wisconsin (US) community pharmacists. Organization-related workload was measured as staffing adequacy; job-related workload was measured as general and specific job demands; task-related workload was measured as internal and external mental demands. Pharmacists' perceived task performance was assessed for patient profile review and patient consultation. The survey was administered to a random sample of 500 pharmacists who were asked to opt in if they were a community pharmacist. Descriptive statistics and correlations of study variables were determined. Two structural equation models were estimated to examine relationships between the study variables and perceived task performance. From the 224 eligible community pharmacists that agreed to participate, 165 (73.7%) usable surveys were completed and returned. Job satisfaction and job-related monitoring demands had direct positive associations with both dispensing tasks. External task demands were negatively related to perceived patient consultation performance. Indirect effects on both tasks were primarily mediated through job satisfaction, which was positively related to staffing adequacy and cognitive job demands and negatively related to volume job demands. External task demands had an additional indirect effect on perceived patient consultation performance, as it was associated with lower levels of job satisfaction and higher levels of burnout. Allowing community pharmacists to concentrate on tasks and limiting interruptions while performing these tasks are important factors in improving quality of patient care and pharmacist work life. The results have implications for strategies to improve patient safety and pharmacist performance. Copyright © 2014 Elsevier Inc. All rights reserved.

The Association of Subjective Workload Dimensions on Quality of Care and Pharmacist Quality of Work Life

PubMed Central

Chui, Michelle A.; Look, Kevin A.; Mott, David A.

2013-01-01

Background Workload has been described both objectively (e.g., number of prescriptions dispensed per pharmacist) as well as subjectively (e.g., pharmacist’s perception of busyness). These approaches might be missing important characteristics of pharmacist workload that have not been previously identified and measured. Objectives To measure the association of community pharmacists’ workload perceptions at three levels (organization, job, and task) with job satisfaction, burnout, and perceived performance of two tasks in the medication dispensing process. Methods A secondary data analysis was performed using cross-sectional survey data collected from Wisconsin (US) community pharmacists. Organization–related workload was measured as staffing adequacy; job-related workload was measured as general and specific job demands; task-related workload was measured as internal and external mental demands. Pharmacists’ perceived task performance was assessed for patient profile review and patient consultation. The survey was administered to a random sample of 500 pharmacists who were asked to opt in if they were a community pharmacist. Descriptive statistics and correlations of study variables were determined. Two structural equation models were estimated to examine relationships between the study variables and perceived task performance. Results From the 224 eligible community pharmacists that agreed to participate, 165 (73.7%) usable surveys were completed and returned. Job satisfaction and job-related monitoring demands had direct positive associations with both dispensing tasks. External task demands were negatively related to perceived patient consultation performance. Indirect effects on both tasks were primarily mediated through job satisfaction, which was positively related to staffing adequacy and cognitive job demands and negatively related to volume job demands. External task demands had an additional indirect effect on perceived patient consultation performance, as it was associated with lower levels of job satisfaction and higher levels of burnout. Implications/Conclusions Allowing community pharmacists to concentrate on tasks and limiting interruptions while performing these tasks are important factors in improving quality of patient care and pharmacist work life. The results have implications for strategies to improve patient safety and pharmacist performance. PMID:23791360

Task exposures in an office environment: a comparison of methods.

PubMed

Van Eerd, Dwayne; Hogg-Johnson, Sheilah; Mazumder, Anjali; Cole, Donald; Wells, Richard; Moore, Anne

2009-10-01

Task-related factors such as frequency and duration are associated with musculoskeletal disorders in office settings. The primary objective was to compare various task recording methods as measures of exposure in an office workplace. A total of 41 workers from different jobs were recruited from a large urban newspaper (71% female, mean age 41 years SD 9.6). Questionnaire, task diaries, direct observation and video methods were used to record tasks. A common set of task codes was used across methods. Different estimates of task duration, number of tasks and task transitions arose from the different methods. Self-report methods did not consistently result in longer task duration estimates. Methodological issues could explain some of the differences in estimates seen between methods observed. It was concluded that different task recording methods result in different estimates of exposure likely due to different exposure constructs. This work addresses issues of exposure measurement in office environments. It is of relevance to ergonomists/researchers interested in how to best assess the risk of injury among office workers. The paper discusses the trade-offs between precision, accuracy and burden in the collection of computer task-based exposure measures and different underlying constructs captures in each method.

The Actor, Partner, Similarity Effects of Personality, and Interactions with Gender and Relationship Duration among Chinese Emerging Adults

PubMed Central

Zhou, Yixin; Wang, Kexin; Chen, Shuang; Zhang, Jianxin; Zhou, Mingjie

2017-01-01

Understanding personality effects and their role in influencing relationship quality, varied according to gender and relationship duration, could help us better understand close relationships. Participants were Chinese dating dyads and were asked to complete both the Big Five Inventory and Perceived Relationship Quality Component scales. Males and those who had a long-term relationship perceived better relationship quality; individuals who scored higher on agreeableness, conscientiousness, openness, and emotional stability enjoyed better relationship quality; gender and/or relationship duration moderated the actor effect of extraversion and the partner effects of conscientiousness, emotional stability, and openness on relationship quality. Regarding the profile similarity, those couples who were more dissimilar in their profile personality had better relationship quality, especially when they were in a relatively long-term relationship. Meanwhile, with an increase in profile similarity, the males' perceived relationship quality decreased. PMID:29033878

Relationships among Dispositional Ability Conceptions, Intrinsic Motivation, Perceived Competence, Experience, Persistance, and Performance

ERIC Educational Resources Information Center

Li, Weidong; Lee, Amelia M.; Solmon, Melinda A.

2005-01-01

This study was designed to explore the relationships among individuals' dispositional ability conceptions, intrinsic motivation, experience, perceived competence, persistence, and performance. Participants practiced a novel task, completed surveys before instruction and after practicing the task, and completed a skill test. The results indicated…

Processes Involving Perceived Instructional Support, Task Value, and Engagement in Graduate Education

ERIC Educational Resources Information Center

Marchand, Gwen C.; Gutierrez, Antonio P.

2017-01-01

The purpose of this study was to investigate the relations among perceived instructional support (provision of relevance and involvement), subjective task value beliefs (utility, attainment, and intrinsic value), and engagement (behavioral and emotional) over the course of a semester for graduate students enrolled in an introductory research…

Heart Rate Response During Mission-Critical Tasks After Space Flight

NASA Technical Reports Server (NTRS)

Arzeno, Natalia M.; Lee, S. M. C.; Stenger, M. B.; Lawrence, E. L.; Platts, S. H.; Bloomberg, J. J.

2010-01-01

Adaptation to microgravity could impair crewmembers? ability to perform required tasks upon entry into a gravity environment, such as return to Earth, or during extraterrestrial exploration. Historically, data have been collected in a controlled testing environment, but it is unclear whether these physiologic measures result in changes in functional performance. NASA?s Functional Task Test (FTT) aims to investigate whether adaptation to microgravity increases physiologic stress and impairs performance during mission-critical tasks. PURPOSE: To determine whether the well-accepted postflight tachycardia observed during standard laboratory tests also would be observed during simulations of mission-critical tasks during and after recovery from short-duration spaceflight. METHODS: Five astronauts participated in the FTT 30 days before launch, on landing day, and 1, 6, and 30 days after landing. Mean heart rate (HR) was measured during 5 simulations of mission-critical tasks: rising from (1) a chair or (2) recumbent seated position followed by walking through an obstacle course (egress from a space vehicle), (3) translating graduated masses from one location to another (geological sample collection), (4) walking on a treadmill at 6.4 km/h (ambulation on planetary surface), and (5) climbing 40 steps on a passive treadmill ladder (ingress to lander). For tasks 1, 2, 3, and 5, astronauts were encouraged to complete the task as quickly as possible. Time to complete tasks and mean HR during each task were analyzed using repeated measures ANOVA and ANCOVA respectively, in which task duration was a covariate. RESULTS: Landing day HR was higher (P < 0.05) than preflight during the upright seat egress (7%+/-3), treadmill walk (13%+/-3) and ladder climb (10%+/-4), and HR remained elevated during the treadmill walk 1 day after landing. During tasks in which HR was not elevated on landing day, task duration was significantly greater on landing day (recumbent seat egress: 25%+/-14 and mass translation: 26%+/-12; P < 0.05). CONCLUSION: Elevated HR and increased task duration during postflight simulations of mission-critical tasks is suggestive of spaceflight-induced deconditioning. Following short-duration microgravity missions (< 16 d), work performance may be transiently impaired, but recovery is rapid.

Listeners' identification and discrimination of digitally manipulated sounds as prolongations.

PubMed

Kawai, Norimune; Healey, E Charles; Carrell, Thomas D

2007-08-01

The present study had two main purposes. One was to examine if listeners perceive gradually increasing durations of a voiceless fricative categorically ("fluent" versus "stuttered") or continuously (gradient perception from fluent to stuttered). The second purpose was to investigate whether there are gender differences in how listeners perceive various duration of sounds as "prolongations." Forty-four listeners were instructed to rate the duration of the // in the word "shape" produced by a normally fluent speaker. The target word was embedded in the middle of an experimental phrase and the initial // sound was digitally manipulated to create a range of fluent to stuttered sounds. This was accomplished by creating 20 ms stepwise increments for sounds ranging from 120 to 500 ms in duration. Listeners were instructed to give a rating of 1 for a fluent word and a rating of 100 for a stuttered word. The results showed listeners perceived the range of sounds continuously. Also, there was a significant gender difference in that males rated fluent sounds higher than females but female listeners rated stuttered sounds higher than males. The implications of these results are discussed.

Mixtures of beta distributions in models of the duration of a project affected by risk

NASA Astrophysics Data System (ADS)

Gładysz, Barbara; Kuchta, Dorota

2017-07-01

This article presents a method for timetabling a project affected by risk. The times required to carry out tasks are modelled using mixtures of beta distributions. The parameters of these beta distributions are given by experts: one corresponding to the duration of a task in stable conditions, with no risks materializing, and the other corresponding to the duration of a task in the case when risks do occur. Finally, a case study will be presented and analysed: the project of constructing a shopping mall in Poland.

Association between Sleep Duration and Perceived Stress: Salaried Worker in Circumstances of High Workload.

PubMed

Choi, Dong-Woo; Chun, Sung-Youn; Lee, Sang Ah; Han, Kyu-Tae; Park, Eun-Cheol

2018-04-19

The aim of this study was to find the association between sleep duration and perceived stress in salaried workers according to occupational categories and which lifestyle factors affected those correlations in South Korea. This study used data from the 2015 Community Health Survey (CHS). The self-reported sleep duration was used as the dependent variable in this study. We explored sleep duration and stress awareness among salaried workers, as well as household income and educational level with multiple logistic regression analysis. Salaried workers who slept for five or less hours had a higher odds ratio for high-stress awareness (OR: 1.86, 95% CI: 1.74⁻1.98). Stress awareness is associated with short sleep duration; specialized workers, office workers, those with above mid-high household income and graduate, university, or college level workers especially need to sleep adequately to manage stress.

Association between Sleep Duration and Perceived Stress: Salaried Worker in Circumstances of High Workload

PubMed Central

Choi, Dong-Woo; Chun, Sung-Youn; Lee, Sang Ah; Han, Kyu-Tae

2018-01-01

The aim of this study was to find the association between sleep duration and perceived stress in salaried workers according to occupational categories and which lifestyle factors affected those correlations in South Korea. This study used data from the 2015 Community Health Survey (CHS). The self-reported sleep duration was used as the dependent variable in this study. We explored sleep duration and stress awareness among salaried workers, as well as household income and educational level with multiple logistic regression analysis. Salaried workers who slept for five or less hours had a higher odds ratio for high-stress awareness (OR: 1.86, 95% CI: 1.74–1.98). Stress awareness is associated with short sleep duration; specialized workers, office workers, those with above mid-high household income and graduate, university, or college level workers especially need to sleep adequately to manage stress. PMID:29671770

Comparing methods for measuring peak look duration: are individual differences observed on screen-based tasks also found in more ecologically valid contexts?

PubMed

Wass, Sam V

2014-08-01

Convergent research points to the importance of studying the ontogenesis of sustained attention during the early years of life, but little research hitherto has compared and contrasted different techniques available for measuring sustained attention. Here, we compare methods that have been used to assess one parameter of sustained attention, namely infants' peak look duration to novel stimuli. Our focus was to assess whether individual differences in peak look duration are stable across different measurement techniques. In a single cohort of 42 typically developing 11-month-old infants we assessed peak look duration using six different measurement paradigms (four screen-based, two naturalistic). Zero-order correlations suggested that individual differences in peak look duration were stable across all four screen-based paradigms, but no correlations were found between peak look durations observed on the screen-based and the naturalistic paradigms. A factor analysis conducted on the dependent variable of peak look duration identified two factors. All four screen-based tasks loaded onto the first factor, but the two naturalistic tasks did not relate, and mapped onto a different factor. Our results question how individual differences observed on screen-based tasks manifest in more ecologically valid contexts. Copyright © 2014 The Authors. Published by Elsevier Inc. All rights reserved.

Comparing methods for measuring peak look duration: Are individual differences observed on screen-based tasks also found in more ecologically valid contexts?

PubMed Central

Wass, Sam V.

2014-01-01

Convergent research points to the importance of studying the ontogenesis of sustained attention during the early years of life, but little research hitherto has compared and contrasted different techniques available for measuring sustained attention. Here, we compare methods that have been used to assess one parameter of sustained attention, namely infants’ peak look duration to novel stimuli. Our focus was to assess whether individual differences in peak look duration are stable across different measurement techniques. In a single cohort of 42 typically developing 11-month-old infants we assessed peak look duration using six different measurement paradigms (four screen-based, two naturalistic). Zero-order correlations suggested that individual differences in peak look duration were stable across all four screen-based paradigms, but no correlations were found between peak look durations observed on the screen-based and the naturalistic paradigms. A factor analysis conducted on the dependent variable of peak look duration identified two factors. All four screen-based tasks loaded onto the first factor, but the two naturalistic tasks did not relate, and mapped onto a different factor. Our results question how individual differences observed on screen-based tasks manifest in more ecologically valid contexts. PMID:24905901

Examining the response programming function of the Quiet Eye: Do tougher shots need a quieter eye?

PubMed

Walters-Symons, Rosanna; Wilson, Mark; Klostermann, Andre; Vine, Samuel

2018-02-01

Support for the proposition that the Quiet Eye (QE) duration reflects a period of response programming (including task parameterisation) has come from research showing that an increase in task difficulty is associated with increases in QE duration. Here, we build on previous research by manipulating three elements of task difficulty that correspond with different parameters of golf-putting performance; force production, impact quality and target line. Longer QE durations were found for more complex iterations of the task and furthermore, more sensitive analyses of the QE duration suggest that the early QE proportion (prior to movement initiation) is closely related to force production and impact quality. However, these increases in QE do not seem functional in terms of supporting improved performance. Further research is needed to explore QE's relationship with performance under conditions of increased difficulty.

Awareness of Rhythm Patterns in Speech and Music in Children with Specific Language Impairments

PubMed Central

Cumming, Ruth; Wilson, Angela; Leong, Victoria; Colling, Lincoln J.; Goswami, Usha

2015-01-01

Children with specific language impairments (SLIs) show impaired perception and production of language, and also show impairments in perceiving auditory cues to rhythm [amplitude rise time (ART) and sound duration] and in tapping to a rhythmic beat. Here we explore potential links between language development and rhythm perception in 45 children with SLI and 50 age-matched controls. We administered three rhythmic tasks, a musical beat detection task, a tapping-to-music task, and a novel music/speech task, which varied rhythm and pitch cues independently or together in both speech and music. Via low-pass filtering, the music sounded as though it was played from a low-quality radio and the speech sounded as though it was muffled (heard “behind the door”). We report data for all of the SLI children (N = 45, IQ varying), as well as for two independent subgroupings with intact IQ. One subgroup, “Pure SLI,” had intact phonology and reading (N = 16), the other, “SLI PPR” (N = 15), had impaired phonology and reading. When IQ varied (all SLI children), we found significant group differences in all the rhythmic tasks. For the Pure SLI group, there were rhythmic impairments in the tapping task only. For children with SLI and poor phonology (SLI PPR), group differences were found in all of the filtered speech/music AXB tasks. We conclude that difficulties with rhythmic cues in both speech and music are present in children with SLIs, but that some rhythmic measures are more sensitive than others. The data are interpreted within a “prosodic phrasing” hypothesis, and we discuss the potential utility of rhythmic and musical interventions in remediating speech and language difficulties in children. PMID:26733848

Awareness of Rhythm Patterns in Speech and Music in Children with Specific Language Impairments.

PubMed

Cumming, Ruth; Wilson, Angela; Leong, Victoria; Colling, Lincoln J; Goswami, Usha

2015-01-01

Children with specific language impairments (SLIs) show impaired perception and production of language, and also show impairments in perceiving auditory cues to rhythm [amplitude rise time (ART) and sound duration] and in tapping to a rhythmic beat. Here we explore potential links between language development and rhythm perception in 45 children with SLI and 50 age-matched controls. We administered three rhythmic tasks, a musical beat detection task, a tapping-to-music task, and a novel music/speech task, which varied rhythm and pitch cues independently or together in both speech and music. Via low-pass filtering, the music sounded as though it was played from a low-quality radio and the speech sounded as though it was muffled (heard "behind the door"). We report data for all of the SLI children (N = 45, IQ varying), as well as for two independent subgroupings with intact IQ. One subgroup, "Pure SLI," had intact phonology and reading (N = 16), the other, "SLI PPR" (N = 15), had impaired phonology and reading. When IQ varied (all SLI children), we found significant group differences in all the rhythmic tasks. For the Pure SLI group, there were rhythmic impairments in the tapping task only. For children with SLI and poor phonology (SLI PPR), group differences were found in all of the filtered speech/music AXB tasks. We conclude that difficulties with rhythmic cues in both speech and music are present in children with SLIs, but that some rhythmic measures are more sensitive than others. The data are interpreted within a "prosodic phrasing" hypothesis, and we discuss the potential utility of rhythmic and musical interventions in remediating speech and language difficulties in children.

The perception of stress and intonation in children with a cochlear implant and a hearing aid.

PubMed

Hegarty, Lauren; Faulkner, Andrew

2013-11-01

This study investigated whether low frequency information from a hearing aid improved the perception of stress and intonation by English-speaking children with cochlear implants. As pitch information is limited for cochlear implant users, this study also investigated if users rely more on the cues of duration and amplitude to perceive stress and intonation. Nine children with bimodal stimulation (cochlear implant and hearing aid) participated in two experiments. The first measured the just audible change in F0 (pitch) and amplitude for a speech-like word 'baba'. The second experiment examined the children's ability to identify focus in natural and manipulated sentences. Overall, group results did not show a bimodal advantage in perceiving stress and intonation. However, the children were significantly better at perceiving focus in sentences with natural speech compared with manipulated speech in both the CI and bimodal conditions. The results suggest that in the absence of pitch cues, amplitude and duration cues are used to perceive stress and intonation. However, the majority of children only perceived amplitude changes greater than the changes typically found in speech, implying duration cues were the most valuable. Taken together the findings suggest that for children with cochlear implants, cues to F0 may not be essential for prosody perception and in the absence of cues to F0 and amplitude, duration may offer an alternative cue. Although a bimodal advantage was not demonstrated for all participants, it is recommended that if clinically appropriate, a contralateral hearing aid is fitted and trialled to exploit any residual hearing.

Short-Term Memory for Time in Children and Adults: A Behavioral Study and a Model

ERIC Educational Resources Information Center

Droit-Volet, Sylvie; Wearden, John; Delgado-Yonger, Maria

2007-01-01

This experiment investigated the effect of the short-term retention of duration on temporal discrimination in 5- and 8-year-olds, as well as in adults, by using an episodic temporal generalization task. In each age group, the participants' task was to compare two successive durations (a standard and a comparison duration) separated by a retention…

Context-Dependent Duration Signals in the Primate Prefrontal Cortex

PubMed Central

Genovesio, Aldo; Seitz, Lucia K.; Tsujimoto, Satoshi; Wise, Steven P.

2016-01-01

The activity of some prefrontal (PF) cortex neurons distinguishes short from long time intervals. Here, we examined whether this property reflected a general timing mechanism or one dependent on behavioral context. In one task, monkeys discriminated the relative duration of 2 stimuli; in the other, they discriminated the relative distance of 2 stimuli from a fixed reference point. Both tasks had a pre-cue period (interval 1) and a delay period (interval 2) with no discriminant stimulus. Interval 1 elapsed before the presentation of the first discriminant stimulus, and interval 2 began after that stimulus. Both intervals had durations of either 400 or 800 ms. Most PF neurons distinguished short from long durations in one task or interval, but not in the others. When neurons did signal something about duration for both intervals, they did so in an uncorrelated or weakly correlated manner. These results demonstrate a high degree of context dependency in PF time processing. The PF, therefore, does not appear to signal durations abstractedly, as would be expected of a general temporal encoder, but instead does so in a highly context-dependent manner, both within and between tasks. PMID:26209845

Ego depletion in visual perception: Ego-depleted viewers experience less ambiguous figure reversal.

PubMed

Wimmer, Marina C; Stirk, Steven; Hancock, Peter J B

2017-10-01

This study examined the effects of ego depletion on ambiguous figure perception. Adults (N = 315) received an ego depletion task and were subsequently tested on their inhibitory control abilities that were indexed by the Stroop task (Experiment 1) and their ability to perceive both interpretations of ambiguous figures that was indexed by reversal (Experiment 2). Ego depletion had a very small effect on reducing inhibitory control (Cohen's d = .15) (Experiment 1). Ego-depleted participants had a tendency to take longer to respond in Stroop trials. In Experiment 2, ego depletion had small to medium effects on the experience of reversal. Ego-depleted viewers tended to take longer to reverse ambiguous figures (duration to first reversal) when naïve of the ambiguity and experienced less reversal both when naïve and informed of the ambiguity. Together, findings suggest that ego depletion has small effects on inhibitory control and small to medium effects on bottom-up and top-down perceptual processes. The depletion of cognitive resources can reduce our visual perceptual experience.

Sex differences in kinematic adaptations to muscle fatigue induced by repetitive upper limb movements.

PubMed

Bouffard, Jason; Yang, Chen; Begon, Mickael; Côté, Julie

2018-04-19

Muscle fatigue induced by repetitive movements contributes to the development of musculoskeletal disorders. Men and women respond differently to muscle fatigue during isometric single-joint efforts, but sex differences during dynamic multi-joint tasks have not been clearly identified. Moreover, most studies comparing men and women during fatigue development assessed endurance time. However, none evaluated sex differences in kinematic adaptations to fatigue during multi-joint dynamic tasks. The objective of the study was to compare how men and women adapt their upper body kinematics during a fatiguing repetitive pointing task. Forty men and 41 women performed repetitive pointing movements (one per second) between two targets while maintaining their elbow elevated at shoulder height. The task ended when participants rated a perceived level of fatigue of 8/10. Trunk, humerothoracic, and elbow angles were compared between the first and last 30 s of the experiment and between men and women. Linear positions of the index finger (distance from the target) and the elbow (arm elevation) as well as movement timing were documented as task performance measures. Men (7.4 ± 3.2 min) and women (8.3 ± 4.5 min) performed the repetitive pointing task for a similar duration. For both sex groups, trunk range of motion increased with fatigue while shoulder's and elbow's decreased. Moreover, participants modified their trunk posture to compensate for the decreased humerothoracic elevation. Movements at all joints also became more variable with fatigue. However, of the 24 joint angle variables assessed, only two Sex × Fatigue interactions were observed. Although average humerothoracic elevation angle decreased in both subgroups, this decrease was greater in men (standardized response mean [SRM] - 1.63) than in women (SRM - 1.44). Moreover, the movement-to-movement variability of humerothoracic elevation angle increased only in women (SRM 0.42). Despite many similarities between men's and women's response to fatigue induced by repetitive pointing movements, some sex differences were observed. Those subtle differences may indicate that men's shoulder muscles were more fatigued than women's despite a similar level of perceived exertion. They may also indicate that men and women do not adapt the exact same way to a similar fatigue.

The Quiet Eye and Motor Expertise: Explaining the “Efficiency Paradox”

PubMed Central

Klostermann, André; Hossner, Ernst-Joachim

2018-01-01

It has been consistently reported that experts show longer quiet eye (QE) durations when compared to near-experts and novices. However, this finding is rather paradoxical as motor expertise is characterized by an economization of motor-control processes rather than by a prolongation in response programming, a suggested explanatory mechanism of the QE phenomenon. Therefore, an inhibition hypothesis was proposed that suggests an inhibition of non-optimal task solutions over movement parametrization, which is particularly necessary in experts due to the great extent and high density of their experienced task-solution space. In the current study, the effect of the task-solution space’ extension was tested by comparing the QE-duration gains in groups that trained a far-aiming task with a small number (low-extent) vs. a large number (high-extent) of task variants. After an extensive training period of more than 750 trials, both groups showed superior performance in post-test and retention test when compared to pretest and longer QE durations in post-test when compared to pretest. However, the QE durations dropped to baseline values at retention. Finally, the expected additional gain in QE duration for the high-extent group was not found and thus, the assumption of long QE durations due to an extended task-solution space was not confirmed. The findings were (by tendency) more in line with the density explanation of the inhibition hypothesis. This density argument suits research revealing a high specificity of motor skills in experts thus providing worthwhile options for future research on the paradoxical relation between the QE and motor expertise. PMID:29472882

Group Cohesion, Collective Efficacy, and Motivational Climate As Predictors of Conductor Support in Music Ensembles

ERIC Educational Resources Information Center

Matthews, Wendy K.; Kitsantas, Anastasia

2007-01-01

In the present study, we examined whether collective efficacy, group cohesion (task and social), and perceived motivational climate (task-involving and ego-involving orientations) in a music ensemble predict instrumentalists' perceived conductor support. Ninety-one (N = 91) skilled high school instrumentalists participated in the study. To assess…

Small Group Conflict: A Look at Equity, Satisfaction, and Styles of Conflict Management.

ERIC Educational Resources Information Center

Wall, Victor D., Jr.; Nolan, Linda L.

1987-01-01

Study of 71 task-oriented groups revealed that perceived inequity was negatively related to amount of expressed satisfaction with the group and positively related to amount of perceived conflict within the group. Inequity was associated more strongly with conflict centered around people than with conflict centered around task; least associated…

Perceiving and Remembering Events Cross-Linguistically: Evidence from Dual-Task Paradigms

ERIC Educational Resources Information Center

Trueswell, John C.; Papafragou, Anna

2010-01-01

What role does language play during attention allocation in perceiving and remembering events? We recorded adults' eye movements as they studied animated motion events for a later recognition task. We compared native speakers of two languages that use different means of expressing motion (Greek and English). In Experiment 1, eye movements revealed…

The effects of control order, feedback, practice, and input device on tracking performance and perceived workload

NASA Technical Reports Server (NTRS)

Hancock, P. A.; Robinson, M. A.

1989-01-01

The present experiment examined the influence of several task-related factors on tracking performance and concomitant workload. The manipulated factors included tracking order, the presence or absence of knowledge of performance, and the control device. Summed root mean square error (rmse) and perceived workload were measured at the termination of each trial. Perceived workload was measured using the NASA Task Load Index (TLX) and the Subjective Workload Assessment Technique (SWAT). Results indicated a large and expected effect for track order on both performance and the perception of load. In general, trackball input was more accurate and judged for lower load than input using a mouse. The presence or absence of knowledge of performance had little effect on either performance or workload. There were a number of interactions between factors shown in performance that were mirrored by perceived workload scores. Results from each workload scale were equivalent in terms of sensitivity to task manipulations. The pattern of results affirm the utility of these workload measures in assessing the imposed load of multiple task-related variables.

Relationship of perceived environmental barriers and disability in community-dwelling elderly in Taiwan – a population-based study

PubMed Central

2014-01-01

Background To identify the relationship between perceived environmental barriers and disability in community-dwelling elderly. Methods Cross-sectional study in two community service centers in Tainan. We enrolled 200 community-dwelling residents, aged above 65 years, who had resided in the same community for at least 12 months. Basic activity of daily living (BADL) and instrumental activity of daily living (IADL) were assessed using the Hierarchy of Care Required (HCR). There were 59 participants in BADL disability and 109 in IADL disability. Perceived environmental barriers were assessed using the Craig Hospital Inventory of Environmental Factors (CHIEF). We used multinomial logistic regression to examine the relationship of perceived environmental barriers and disability. Results The presence of perceived environmental barriers was related to BADL disability (OR = 4.39, 95% CI = 1.01-19.11) and IADL disability (IADL with difficulty in 1–2 tasks: OR = 9.93, 95% CI = 3.22-30.56; IADL with difficulty in more than 2 tasks: OR = 8.40, 95% CI = 1.83-38.51). The presence of physically/structurally perceived environmental barriers was related to BADL disability (OR = 4.90, 95% CI = 1.01-23.86) and IADL disability (IADL with difficulty in 1–2 tasks: OR = 4.61, 95% CI = 1.27-16.76; IADL with difficulty in more than 2 tasks: OR = 17.05, 95% CI = 2.82-103.30). Conclusions Perceived environmental barriers are related to disability in community-dwelling elderly. PMID:24885956

Is Borg's perceived exertion scale a useful indicator of muscular and cardiovascular load in blue-collar workers with lifting tasks? A cross-sectional workplace study.

PubMed

Jakobsen, Markus Due; Sundstrup, Emil; Persson, Roger; Andersen, Christoffer H; Andersen, Lars L

2014-02-01

To investigate associations between perceived exertion and objectively assessed muscular and cardiovascular load during a full working day among workers with manual lifting tasks. A total of 159 men and 41 women from 14 workplaces with manual lifting tasks participated. Participants reported perceived exertion (BORG-CR10) at midday and after work. Surface electromyography of the thigh, lower back and neck muscles were normalized to isometric voluntary contractions (MVC) to express relative muscle load during the day. Cardiovascular load was measured with electrocardiography and calculated as the average percentage of the heart rate reserve capacity (((heart rate during work - resting heart rate) / (maximum heart rate - resting heart rate)) * 100) during the day. Using linear regression, significant but weak associations (β < 0.23) were observed between perceived exertion and (1) high muscle activity (>60% of MVC) of the neck muscles and (2) inactivity (<1% of MVC) of the thigh muscles and (3) cardiovascular load, respectively. Using logistic regression, perceived exertion ≥4 (high exertion), referencing <4 (low-to-moderate exertion), was related to high activity of the trapezius muscle [OR 18 (95% CI 2-143)], i.e., the odds for experiencing high exertion during work increased 18-fold for each percentage increase in time above 60% MVC. During a full working day among blue-collar workers with lifting tasks, high neck muscle activity increases the odds for experiencing high perceived physical exertion. Perceived exertion of at least 4 on the BORG CR10 scale appears to be a good indicator that high muscular loading occurs.

Schedule Risk Assessment

NASA Technical Reports Server (NTRS)

Smith, Greg

2003-01-01

Schedule Risk Assessment needs to determine the probability of finishing on or before a given point in time. Task in a schedule should reflect the "most likely" duration for each task. IN reality, each task is different and has a varying degree of probability of finishing within or after the duration specified. Schedule risk assessment attempt to quantify these probabilities by assigning values to each task. Bridges the gap between CPM scheduling and the project's need to know the likelihood of "when".

Smell or vision? The use of different sensory modalities in predator discrimination.

PubMed

Fischer, Stefan; Oberhummer, Evelyne; Cunha-Saraiva, Filipa; Gerber, Nina; Taborsky, Barbara

2017-01-01

Theory predicts that animals should adjust their escape responses to the perceived predation risk. The information animals obtain about potential predation risk may differ qualitatively depending on the sensory modality by which a cue is perceived. For instance, olfactory cues may reveal better information about the presence or absence of threats, whereas visual information can reliably transmit the position and potential attack distance of a predator. While this suggests a differential use of information perceived through the two sensory channels, the relative importance of visual vs. olfactory cues when distinguishing between different predation threats is still poorly understood. Therefore, we exposed individuals of the cooperatively breeding cichlid Neolamprologus pulcher to a standardized threat stimulus combined with either predator or non-predator cues presented either visually or chemically. We predicted that flight responses towards a threat stimulus are more pronounced if cues of dangerous rather than harmless heterospecifics are presented and that N. pulcher , being an aquatic species, relies more on olfaction when discriminating between dangerous and harmless heterospecifics. N. pulcher responded faster to the threat stimulus, reached a refuge faster and entered a refuge more likely when predator cues were perceived. Unexpectedly, the sensory modality used to perceive the cues did not affect the escape response or the duration of the recovery phase. This suggests that N. pulcher are able to discriminate heterospecific cues with similar acuity when using vision or olfaction. We discuss that this ability may be advantageous in aquatic environments where the visibility conditions strongly vary over time. The ability to rapidly discriminate between dangerous predators and harmless heterospecifics is crucial for the survival of prey animals. In seasonally fluctuating environment, sensory conditions may change over the year and may make the use of multiple sensory modalities for heterospecific discrimination highly beneficial. Here we compared the efficacy of visual and olfactory senses in the discrimination ability of the cooperatively breeding cichlid Neolamprologus pulcher . We presented individual fish with visual or olfactory cues of predators or harmless heterospecifics and recorded their flight response. When exposed to predator cues, individuals responded faster, reached a refuge faster and were more likely to enter the refuge. Unexpectedly, the olfactory and visual senses seemed to be equally efficient in this discrimination task, suggesting that seasonal variation of water conditions experienced by N. pulcher may necessitate the use of multiple sensory channels for the same task.

Affective processes in human-automation interactions.

PubMed

Merritt, Stephanie M

2011-08-01

This study contributes to the literature on automation reliance by illuminating the influences of user moods and emotions on reliance on automated systems. Past work has focused predominantly on cognitive and attitudinal variables, such as perceived machine reliability and trust. However, recent work on human decision making suggests that affective variables (i.e., moods and emotions) are also important. Drawing from the affect infusion model, significant effects of affect are hypothesized. Furthermore, a new affectively laden attitude termed liking is introduced. Participants watched video clips selected to induce positive or negative moods, then interacted with a fictitious automated system on an X-ray screening task At five time points, important variables were assessed including trust, liking, perceived machine accuracy, user self-perceived accuracy, and reliance.These variables, along with propensity to trust machines and state affect, were integrated in a structural equation model. Happiness significantly increased trust and liking for the system throughout the task. Liking was the only variable that significantly predicted reliance early in the task. Trust predicted reliance later in the task, whereas perceived machine accuracy and user self-perceived accuracy had no significant direct effects on reliance at any time. Affective influences on automation reliance are demonstrated, suggesting that this decision-making process may be less rational and more emotional than previously acknowledged. Liking for a new system may be key to appropriate reliance, particularly early in the task. Positive affect can be easily induced and may be a lever for increasing liking.

The Influence of a Model's Reinforcement Contingency and Affective Response on Children's Perceptions of the Model

ERIC Educational Resources Information Center

Thelen, Mark H.; And Others

1977-01-01

Assesses the influence of model consequences on perceived model affect and, conversely, assesses the influence of model affect on perceived model consequences. Also appraises the influence of model consequences and model affect on perceived model attractiveness, perceived model competence, and perceived task attractiveness. (Author/RK)

Rolling into spatial disorientation: simulator demonstration of the post-roll (Gillingham) illusion.

PubMed

Nooij, Suzanne A E; Groen, Eric L

2011-05-01

Spatial disorientation (SD) is still a contributing factor in many aviation accidents, stressing the need for adequate SD training scenarios. In this article we focused on the post-roll effect (the sensation of rolling back after a roll maneuver, such as an entry of a coordinated turn) and investigated the effect of roll stimuli on the pilot's ability to stabilize their roll attitude. This resulted in a ground-based demonstration scenario for pilots. The experiments took place in the advanced 6-DOF Desdemona motion simulator, with the subject in a supine position. Roll motions were either fully automated with the subjects blindfolded (BLIND), automated with the subject viewing the cockpit interior (COCKPIT), or self-controlled (LEAD). After the roll stimulus subjects had to cancel all perceived simulator motion without any visual feedback. Both the roll velocity and duration were varied. In 68% of all trials subjects corrected for the perceived motion of rolling back by initiating a roll motion in the same direction as the preceeding roll. The effect was dependent on both rate and duration, in a manner consistent with semicircular canal dynamics. The effect was smallest in the BLIND scenario, but differences between simulation scenarios were non-significant. The results show that the effects of the post-roll illusion on aircraft control can be demonstrated adequately in a flight simulator using an attitude control task. The effect is present even after short roll movements, occurring frequently in flight. Therefore this demonstration is relevant for spatial disorientation training programs for pilots.

Striving for group agency: threat to personal control increases the attractiveness of agentic groups.

PubMed

Stollberg, Janine; Fritsche, Immo; Bäcker, Anna

2015-01-01

When their sense of personal control is threatened people try to restore perceived control through the social self. We propose that it is the perceived agency of ingroups that provides the self with a sense of control. In three experiments, we for the first time tested the hypothesis that threat to personal control increases the attractiveness of being part or joining those groups that are perceived as coherent entities engaging in coordinated group goal pursuit (agentic groups) but not of those groups whose agency is perceived to be low. Consistent with this hypothesis we found in Study 1 (N = 93) that threat to personal control increased ingroup identification only with task groups, but not with less agentic types of ingroups that were made salient simultaneously. Furthermore, personal control threat increased a sense of collective control and support within the task group, mediated through task-group identification (indirect effects). Turning to groups people are not (yet) part of, Study 2 (N = 47) showed that personal control threat increased relative attractiveness ratings of small groups as possible future ingroups only when the relative agency of small groups was perceived to be high. Perceived group homogeneity or social power did not moderate the effect. Study 3 (N = 78) replicated the moderating role of perceived group agency for attractiveness ratings of entitative groups, whereas perceived group status did not moderate the effect. These findings extend previous research on group-based control, showing that perceived agency accounts for group-based responses to threatened control.

Task Analysis of Shuttle Entry and Landing Activities

NASA Technical Reports Server (NTRS)

Holland, Albert W.; Vanderark, Stephen T.

1993-01-01

The Task Analysis of Shuttle Entry and Landing (E/L) Activities documents all tasks required to land the Orbiter following an STS mission. In addition to analysis of tasks performed, task conditions are described, including estimated time for completion, altitude, relative velocity, normal and lateral acceleration, location of controls operated or monitored, and level of g's experienced. This analysis precedes further investigations into potential effects of zero g on piloting capabilities for landing the Orbiter following long-duration missions. This includes, but is not limited to, researching the effects of extended duration missions on piloting capabilities. Four primary constraints of the analysis must be clarified: (1) the analysis depicts E/L in a static manner--the actual process is dynamic; (2) the task analysis was limited to a paper analysis, since it was not feasible to conduct research in the actual setting (i.e., observing or filming duration an actual E/L); (3) the tasks included are those required for E/L during nominal, daylight conditions; and (4) certain E/L tasks will vary according to the flying style of each commander.

Perceived reachability in hemispace.

PubMed

Gabbard, Carl; Ammar, Diala; Rodrigues, Luis

2005-07-01

A common observation in studies of perceived (imagined) compared to actual movement in a reaching paradigm is the tendency to overestimate. Of the studies noted, reaching tasks have been presented in the general midline range. In the present study, strong right-handers were asked to judge the reachability of visual targets projected onto a table surface at midline, right- (RVF), and left-visual fields (LVF). Midline results support those of previous studies, showing an overestimation bias. In contrast, participants revealed the tendency to underestimate their reachability in RVF and LVF. These findings are discussed from the perspective of actor 'confidence' (a cognitive state) possibly associated with visual information, perceived ability, and perceived task demands.

Exploring methodological frameworks for a mental task-based near-infrared spectroscopy brain-computer interface.

PubMed

Weyand, Sabine; Takehara-Nishiuchi, Kaori; Chau, Tom

2015-10-30

Near-infrared spectroscopy (NIRS) brain-computer interfaces (BCIs) enable users to interact with their environment using only cognitive activities. This paper presents the results of a comparison of four methodological frameworks used to select a pair of tasks to control a binary NIRS-BCI; specifically, three novel personalized task paradigms and the state-of-the-art prescribed task framework were explored. Three types of personalized task selection approaches were compared, including: user-selected mental tasks using weighted slope scores (WS-scores), user-selected mental tasks using pair-wise accuracy rankings (PWAR), and researcher-selected mental tasks using PWAR. These paradigms, along with the state-of-the-art prescribed mental task framework, where mental tasks are selected based on the most commonly used tasks in literature, were tested by ten able-bodied participants who took part in five NIRS-BCI sessions. The frameworks were compared in terms of their accuracy, perceived ease-of-use, computational time, user preference, and length of training. Most notably, researcher-selected personalized tasks resulted in significantly higher accuracies, while user-selected personalized tasks resulted in significantly higher perceived ease-of-use. It was also concluded that PWAR minimized the amount of data that needed to be collected; while, WS-scores maximized user satisfaction and minimized computational time. In comparison to the state-of-the-art prescribed mental tasks, our findings show that overall, personalized tasks appear to be superior to prescribed tasks with respect to accuracy and perceived ease-of-use. The deployment of personalized rather than prescribed mental tasks ought to be considered and further investigated in future NIRS-BCI studies. Copyright © 2015 Elsevier B.V. All rights reserved.

The Association between Dual-Task Gait after Concussion and Prolonged Symptom Duration.

PubMed

Howell, David R; Brilliant, Anna; Berkstresser, Brant; Wang, Francis; Fraser, Joana; Meehan, William P

2017-12-01

Quantitative gait measurements can identify persistent postconcussion impairments. However, their prognostic utility after injury to identify the likelihood of prolonged concussion symptoms remains unknown. Our objective was to examine if dual-task gait performance measures are independently associated with persistent (> 28 days) concussion symptoms among a sample of athletes. Sixty individuals diagnosed with a sport-related concussion were assessed within 10 days of their injury. Each participant completed a postconcussion symptom scale, an injury history questionnaire, and a single/dual-task gait examination. They were followed until they no longer reported symptoms, and the duration of time required for symptom resolution was calculated. A binary multivariable logistic regression model determined the independent association between dual-task gait and symptom duration (≤ 28 days vs. >28 days) while controlling for the effect of gender, age, symptom severity, injury-to-examination time, and history of concussion. Seventeen (28%) participants reported a symptom duration >28 days. The dual-task cost for average gait speed (-25.9 ± 9.5% vs. -19.8 ± 8.9%; p = 0.027) and cadence (-18.0 ± 2.9% vs. -12.0 ± 7.7%; p = 0.029) was significantly greater among participants who experienced symptoms for >28 days. After adjusting for potential confounding variables, greater dual-task average gait speed costs were independently associated with prolonged symptom duration (aOR = 0.908; 95% CI = 0.835-0.987). Examinations of dual-task gait may provide useful information during multifaceted concussion examinations. Quantitative assessments that simultaneously test multiple domains, such as dual tasks, may be clinically valuable after a concussion to identify those more likely to experience symptoms for >28 days after injury.

Does order and timing in performance of imagined and actual movements affect the motor imagery process? The duration of walking and writing task.

PubMed

Papaxanthis, Charalambos; Pozzo, Thierry; Skoura, Xanthi; Schieppati, Marco

2002-08-21

The purpose of the present study was to investigate the effects on the duration of imagined movements of changes in timing and order of performance of actual and imagined movement. Two groups of subjects had to actually execute and imagine a walking and a writing task. The first group first executed 10 trials of the actual movements (block A) and then imagined the same movements at different intervals: immediately after actual movements (block I-1) and after 25 min (I-2), 50 min (I-3) and 75 min (I-4) interval. The second group first imagined and then actually executed the tasks. The duration of actual and imagined movements, recorded by means of an electronic stopwatch operated by the subjects, was analysed. The duration of imagined movements was very similar to those of actual movements, for both tasks, regardless of either the interval elapsed from the actual movements (first group) or the order of performance (second group). However, the variability of imagined movement duration was significantly increased compared to variability of the actual movements, for both motor tasks and groups. The findings give evidence of similar cognitive processes underlying both imagination and actual performance of movement. Copyright 2002 Elsevier Science B.V.

Response terminated displays unload selective attention

PubMed Central

Roper, Zachary J. J.; Vecera, Shaun P.

2013-01-01

Perceptual load theory successfully replaced the early vs. late selection debate by appealing to adaptive control over the efficiency of selective attention. Early selection is observed unless perceptual load (p-Load) is sufficiently low to grant attentional “spill-over” to task-irrelevant stimuli. Many studies exploring load theory have used limited display durations that perhaps impose artificial limits on encoding processes. We extended the exposure duration in a classic p-Load task to alleviate temporal encoding demands that may otherwise tax mnemonic consolidation processes. If the load effect arises from perceptual demands alone, then freeing-up available mnemonic resources by extending the exposure duration should have little effect. The results of Experiment 1 falsify this prediction. We observed a reliable flanker effect under high p-Load, response-terminated displays. Next, we orthogonally manipulated exposure duration and task-relevance. Counter-intuitively, we found that the likelihood of observing the flanker effect under high p-Load resides with the duration of the task-relevant array, not the flanker itself. We propose that stimulus and encoding demands interact to produce the load effect. Our account clarifies how task parameters differentially impinge upon cognitive processes to produce attentional “spill-over” by appealing to visual short-term memory as an additional processing bottleneck when stimuli are briefly presented. PMID:24399983

Response terminated displays unload selective attention.

PubMed

Roper, Zachary J J; Vecera, Shaun P

2013-01-01

Perceptual load theory successfully replaced the early vs. late selection debate by appealing to adaptive control over the efficiency of selective attention. Early selection is observed unless perceptual load (p-Load) is sufficiently low to grant attentional "spill-over" to task-irrelevant stimuli. Many studies exploring load theory have used limited display durations that perhaps impose artificial limits on encoding processes. We extended the exposure duration in a classic p-Load task to alleviate temporal encoding demands that may otherwise tax mnemonic consolidation processes. If the load effect arises from perceptual demands alone, then freeing-up available mnemonic resources by extending the exposure duration should have little effect. The results of Experiment 1 falsify this prediction. We observed a reliable flanker effect under high p-Load, response-terminated displays. Next, we orthogonally manipulated exposure duration and task-relevance. Counter-intuitively, we found that the likelihood of observing the flanker effect under high p-Load resides with the duration of the task-relevant array, not the flanker itself. We propose that stimulus and encoding demands interact to produce the load effect. Our account clarifies how task parameters differentially impinge upon cognitive processes to produce attentional "spill-over" by appealing to visual short-term memory as an additional processing bottleneck when stimuli are briefly presented.

Neuroimaging somatosensory perception and masking.

PubMed

Meador, Kimford J; Revill, Kathleen Pirog; Epstein, Charles M; Sathian, K; Loring, David W; Rorden, Chris

2017-01-08

The specific cortical and subcortical regions involved in conscious perception and masking are uncertain. This study sought to identify brain areas involved in conscious perception of somatosensory stimuli during a masking task using functional magnetic resonance (fMRI) to contrast perceived vs. non-perceived targets. Electrical trains were delivered to the right index finger for targets and to the left index finger for masks. Target intensities were adjusted to compensate for threshold drift. Sham target trials were given in ~10% of the trials, and target stimuli without masks were delivered in one of the five runs (68 trials/run). When healthy dextral adult volunteers (n=15) perceived right hand targets, greater left- than right-cerebral activations were seen with similar patterns across the parietal cortex, thalamus, insula, claustrum, and midbrain. When targets were not perceived, left/right cerebral activations were similar overall. Directly comparing perceived vs. non-perceived stimuli with similar intensities in the masking task revealed predominate activations contralateral to masks. In contrast, activations were greater contralateral to perceived targets if no masks were given or if masks were given but target stimulus intensities were greater for perceived than non-perceived targets. The novel aspects of this study include: 1) imaging of cortical and subcortical activations in healthy humans related to somatosensory perception during a masking task, 2) activations in the human thalamus and midbrain related to perception of stimuli compared to matched non-perceived stimuli, and 3) similar left/right cerebral activation patterns across cortical, thalamic and midbrain structures suggesting interactions across all three levels during conscious perception in humans. Copyright © 2016 Elsevier Ltd. All rights reserved.

Kinematic measures of Arm-trunk movements during unilateral and bilateral reaching predict clinically important change in perceived arm use in daily activities after intensive stroke rehabilitation.

PubMed

Chen, Hao-ling; Lin, Keh-chung; Liing, Rong-jiuan; Wu, Ching-yi; Chen, Chia-ling

2015-09-21

Kinematic analysis has been used to objectively evaluate movement patterns, quality, and strategies during reaching tasks. However, no study has investigated whether kinematic variables during unilateral and bilateral reaching tasks predict a patient's perceived arm use during activities of daily living (ADL) after an intensive intervention. Therefore, this study investigated whether kinematic measures during unilateral and bilateral reaching tasks before an intervention can predict clinically meaningful improvement in perceived arm use during ADL after intensive poststroke rehabilitation. The study was a secondary analysis of 120 subjects with chronic stroke who received 90-120 min of intensive intervention every weekday for 3-4 weeks. Reaching kinematics during unilateral and bilateral tasks and the Motor Activity Log (MAL) were evaluated before and after the intervention. Kinematic variables explained 22 and 11 % of the variance in actual amount of use (AOU) and quality of movement (QOM), respectively, of MAL improvement during unilateral reaching tasks. Kinematic variables also explained 21 and 31 % of the variance in MAL-AOU and MAL-QOM, respectively, during bilateral reaching tasks. Selected kinematic variables, including endpoint variables, trunk involvement, and joint recruitment and interjoint coordination, were significant predictors for improvement in perceived arm use during ADL (P < 0.05). Arm-trunk kinematics may be used to predict clinically meaningful improvement in perceived arm use during ADL after intensive rehabilitation. Involvement of interjoint coordination and trunk control variables as predictors in bilateral reaching models indicates that a high level of motor control (i.e., multijoint coordination) and trunk stability may be important in obtaining treatment gains in arm use, especially for bilateral daily activities, in intensive rehabilitation after stroke.

Perceived Dentist and Dental Hygienist Task Distribution After Dental and Dental Hygiene Students' Team Intervention.

PubMed

Reinders, Jan J; Krijnen, Wim P; Stegenga, Boudewijn; van der Schans, Cees P

2017-04-01

Attitudes of dental students regarding the provision of treatment tend to be dentist-centered; however, facilitating mixed student group formation could change such perceptions. The aim of this study was to investigate the perceived scope of practice of dental and dental hygiene students and whether their perceptions of task distribution between dentists and dental hygienists would change following an educational intervention consisting of feedback, intergroup comparison, and competition between mixed-group teams. The study employed a pretest-posttest single group design. Third-year dental students and second-year dental hygiene students at a university in The Netherlands were randomly assigned to intraprofessional teams (four or five members) and received team-based performance feedback and comparison. The intervention was finalized with an award ceremony for the best intraprofessional team. Before and after the intervention, students completed a questionnaire measuring their perceived distribution of ten tasks between dentists and dental hygienists. A total of 38 dental students and 32 dental hygiene students participated in the intervention-all 70 of those eligible. Questionnaires were completed by a total 88.4% (n=61) of the participants: 34 dental (89.5%) and 27 dental hygiene students (84.4%). Dental and dental hygiene students had similar perceptions regarding teeth cleaning (prophylaxis) (p=0.372, p=0.404) and, after the intervention, preventive tasks (p=0.078). Following the intervention, dental students considered four out of ten tasks as less dentist-centered: radiograph for periodontal diagnosis (p=0.003), local anesthesia (p=0.037), teeth cleaning (p=0.037), and periodontal treatment (p=0.045). Dental hygiene students perceived one task as being less dentist-centered after the intervention: radiograph for cariologic diagnosis (p=0.041). This study found that these dental and dental hygiene students had different opinions regarding the scope of practice for dentistry and dental hygiene. The number of redistributed tasks after the intervention was especially substantial among the dental students, although the amount of change per task was minimal. Half of all tasks were perceived as less dentist-centered as a result of the intervention.

Pacing behaviour of players in team sports: Influence of match status manipulation and task duration knowledge

PubMed Central

Ferraz, Ricardo; Gonçalves, Bruno; Marinho, Daniel A.; Sampaio, Jaime; Marques, Mário C.

2018-01-01

The study aimed to identify the influence of prior knowledge of exercise duration associated with initial information about momentary match status (losing or winning) on the pacing behaviour displayed during soccer game-based activities. Twenty semi-professional male players participated in four game scenarios divided in two sessions. In the first game scenario, players were not informed about the time duration or initial match status. In the second, players were only informed they would be required to play a small-sided game for 12 minutes. In the third, players were told they would play a small-sided game for 12 minutes and that one of the teams was winning 2 to 0. Finally, in the fourth game scenario, players were instructed they would play a small-sided game for 12 minutes and the score lines used at the start of the previous game scenario were reversed. The results showed a tendency for the unknown task duration to elicit greater physical responses in all studied variables, compared with knowing the task duration. Knowing the task duration and starting the game winning or losing did not affect the players’ activity profile between the two conditions. Thus, during small-sided soccer games, knowledge (or not) about the exercise duration alters the pacing behaviour of the players. Moreover, short and undisclosed-length exercise durations resulted in the adoption of more aggressive pacing strategies, characterised by higher initial exercise intensities. Furthermore, previous information on match status does not seem to interfere with pacing patterns if the players are aware of the exercise duration. Coaches may use knowledge of exercise duration to manipulate the small-sided games’ demands. PMID:29401476

Using threshold messages to promote physical activity: implications for public perceptions of health effects.

PubMed

Knox, Emily C L; Webb, Oliver J; Esliger, Dale W; Biddle, Stuart J H; Sherar, Lauren B

2014-04-01

The promotion of physical activity (PA) guidelines to the general public is an important issue that lacks empirical investigation. PA campaigns often feature participation thresholds that cite PA guidelines verbatim [e.g., 150 min/week moderate-to-vigorous physical activity (MVPA)]. Some campaigns instead prefer to use generic PA messages (e.g., do as much MVPA as possible). 'Thresholds' may disrupt understanding of the health benefits of modest PA participation. This study examined the perception of health benefits of PA after exposure to PA messages that did and did not contain a duration threshold. Brief structured interviews were conducted with a convenience sample of adults (n = 1100). Participants received a threshold message (150 min/week MVPA), a message that presented the threshold as a minimum; a generic message or no message. Participants rated perceived health effects of seven PA durations. One-way analyses of variance with post hoc tests for group differences were used to assess raw perception ratings for each duration of PA. Recipients of all three messages held more positive perceptions of >150 min/week of MVPA relative to those not receiving any message. For MVPA durations <150 min/week, the generic PA message group perceived the greatest health benefits. Those receiving the threshold message tended to have the least positive perceptions of durations <150 min/week. Threshold messages were associated with lower perceived health benefits for modest PA durations. Campaigns based on threshold messages may be limited when promoting small PA increases at a population level.

Influence of Significant Others on High School Students' Expectancies of Success and Task Value in Physical Education

ERIC Educational Resources Information Center

Williams, Skip M.; Weiss, Windee

2018-01-01

This study examined the perceived influence of significant others' beliefs on students' expectancies of success and task value in physical education (PE). PE students (N = 231) between Grades 9 and 12 participated. Multiple regressions examined the influence of perceived parents', teachers', and classmates' beliefs on students' ability…

Attainment of Developmental Tasks by Adolescents with Hearing Loss Attending Special Schools

ERIC Educational Resources Information Center

Pinquart, Martin; Pfeiffer, Jens P.

2014-01-01

The investigators compared the perceived attainment of developmental tasks by 181 German adolescents with hearing loss and 254 peers without hearing loss. The adolescents with hearing loss were attending special schools for students who are deaf or hard of hearing. On average, the two groups perceived similar levels of success across the assessed…

Students' Perceptions of Mathematics Classroom Goal Structures: Implications for Perceived Task Values and Study Behavior

ERIC Educational Resources Information Center

Skaalvik, Einar M.; Federici, Roger A.; Wigfield, Allan; Tangen, Truls N.

2017-01-01

Relations between 8th and 10th grade students' perceptions of classroom goal structures, task values, anxiety, help-seeking behavior, and effort in mathematics classes were examined. The authors investigated whether the associations between perceived goal structures and anxiety, help-seeking behavior, and effort are mediated through students'…

The impact of intra-operative interruptions on surgeons' perceived workload: an observational study in elective general and orthopedic surgery.

PubMed

Weigl, Matthias; Antoniadis, Sophia; Chiapponi, Costanza; Bruns, Christiane; Sevdalis, Nick

2015-01-01

Surgeons' intra-operative workload is critical for effective and safe surgical performance. Detrimental conditions in the operating room (OR) environment may add to perceived workload and jeopardize surgical performance and outcomes. This study aims to evaluate the impact of different intra-operative workflow interruptions on surgeons' capacity to manage their workload safely and efficiently. This was an observational study of intra-operative interruptions and self-rated workload in two surgical specialties (general, orthopedic/trauma surgery). Intra-operative interruptions were assessed via expert observation using a well-validated observation tool. Surgeons, nurses, and anesthesiologists assessed their intra-operative workload directly after case completion based on three items of the validated Surgery Task Load Index (mental demand, situational stress, distraction). A total of 56 elective cases (35 open, 21 laparoscopic) with 94 workload ratings were included. Mean intra-operative duration was 1 h 37 min. Intra-operative interruptions were on average observed 9.78 times per hour. People who entered/exited the OR (30.6 %) as well as telephone-/beeper-related disruptions (23.6 %) occurred most often. Equipment and OR environment-related interruptions were associated with highest interference with team functioning particularly in laparoscopic procedures. After identifying task and procedural influences, partial correlational analyses revealed that case-irrelevant communications were negatively associated with surgeons' mental fatigue and situational stress, whereas surgeons' reported distraction was increased by case-irrelevant communication and procedural disruptions. OR nurses' and anesthesiologists' perceived workload was also related to intra-operative interruption events. Our study documents the unique contribution of different interruptions on surgeons' workload; whereas case-irrelevant communications may be beneficial for mental fatigue and stress in routine cases, procedural interruptions and case-irrelevant communication may contribute to surgeons' mental focus deteriorating. Well-designed OR environments, surgical leadership, and awareness can help to control unnecessary interruptions for effective and safe surgical care.

Racial Differences in Self-Reports of Short Sleep Duration in an Urban-Dwelling Environment

PubMed Central

McNeely, Jessica M.; Shah, Mauli T.; Evans, Michele K.; Zonderman, Alan B.

2015-01-01

Objectives. To explore whether there are differences in sleep duration between blacks and whites residing in similar urban neighborhoods and examine whether the relationship between sleep durations and sociodemographic and/or health indices are consistent for blacks and whites. Methods. A total of 1,207 participants from the Healthy Aging in Neighborhoods of Disparities across the Life Span study (age: mean = 47, standard deviation = 8.74). Sleep duration was assessed by a self-report of hours of nightly sleep in the past month. Sociodemographic measures included age, sex, education, poverty status, and perceived neighborhood disorder. Health status was assessed using measures of vigilance, depression, perceived stress, coronary artery disease, diabetes, blood pressure, and inflammation. Results. There were no significant racial group differences in sleep duration. Whites, however, were more likely than blacks to report sleep durations of <6/6–7hr compared with >7hr with increasing stress and education levels. Blacks were more likely than whites to report short sleep durations (i.e., 6–7hr vs. >7hr of sleep) with increasing inflammation levels. Discussion. Although racial disparities in sleep duration are minimized when the environment is equivalent between blacks and whites, the underlying demographic and health explanations for short sleep durations may vary between whites and blacks. PMID:24285771

The Influence of Physician Communication Style on Overweight Patients’ Perceptions of Length of Encounter and Physician Being Rushed

PubMed Central

Gulbrandsen, Pål; Østbye, Truls; Lyna, Pauline; Dolor, Rowena J.; Tulsky, James A.; Alexander, Stewart C.; Pollak, Kathryn I.

2012-01-01

BACKGROUND AND OBJECTIVES Little is known about how patients and physicians perceive time and the extent to which they perceive the physician being rushed during encounters. One aim of this paper is to examine whether patient and physician characteristics and physician communication influence patient perception of the duration of the encounter and their perception of physicians being rushed. Another aim is to examine the relationship between patient and physician perceptions of physicians feeling rushed. METHODS We audiorecorded 461 encounters of overweight or obese patients with 40 primary care physicians and included 320 encounters in which weight was discussed. We calculated time spent with physician and coded all communication about weight using the Motivational Interview Treatment Integrity scale (MITI). Patients completed post-visit questionnaires in which they reported the estimated duration of the encounter and how rushed they thought the physician was during the encounter. Physicians reported how rushed they felt. RESULTS Patients estimated encounters to be longer than they actually were by an average of 2.6 minutes (SD=11.0). When physicians used reflective statements when discussing weight, patients estimated the encounter to be shorter than when physicians did not use reflective statements (1.17 versus 4.56 minutes more than actual duration). Whites perceived the encounter as shorter than African Americans (1.45 versus 4.28 minutes more than actual duration). Physicians felt rushed in 66% of visits; however, most patients did not perceive this. Internists were perceived to be more rushed than family physicians. CONCLUSIONS There is wide variation in patients’ ability to estimate the length of time they spend with their physician. Some physician and patient characteristics were related to patient perceptions of the length of the encounter. Reflective statements might lead patients to perceive encounters as shorter. Physicians, especially family physicians, appear able to conceal that they are feeling rushed. PMID:22399481

Slow motion in films and video clips: Music influences perceived duration and emotion, autonomic physiological activation and pupillary responses.

PubMed

Wöllner, Clemens; Hammerschmidt, David; Albrecht, Henning

2018-01-01

Slow motion scenes are ubiquitous in screen-based audiovisual media and are typically accompanied by emotional music. The strong effects of slow motion on observers are hypothetically related to heightened emotional states in which time seems to pass more slowly. These states are simulated in films and video clips, and seem to resemble such experiences in daily life. The current study investigated time perception and emotional response to media clips containing decelerated human motion, with or without music using psychometric and psychophysiological testing methods. Participants were presented with slow-motion scenes taken from commercial films, ballet and sports footage, as well as the same scenes converted to real-time. Results reveal that slow-motion scenes, compared to adapted real-time scenes, led to systematic underestimations of duration, lower perceived arousal but higher valence, lower respiration rates and smaller pupillary diameters. The presence of music compared to visual-only presentations strongly affected results in terms of higher accuracy in duration estimates, higher perceived arousal and valence, higher physiological activation and larger pupillary diameters, indicating higher arousal. Video genre affected responses in addition. These findings suggest that perceiving slow motion is not related to states of high arousal, but rather affects cognitive dimensions of perceived time and valence. Music influences these experiences profoundly, thus strengthening the impact of stretched time in audiovisual media.

Kinematic cues in perceptual weight judgement and their origins in box lifting

PubMed Central

Hamilton, A.; Joyce, D. W.; Flanagan, R.; Frith, C. D.; Wolpert, D. M.

2009-01-01

When accepting a parcel from another person, we are able to use information about that person’s movement to estimate in advance the weight of the parcel, that is, to judge its weight from observed action. Perceptual weight judgment provides a powerful method to study our interpretation of other people’s actions, but it is not known what sources of information are used in judging weight. We have manipulated full form videos to obtain precise control of the perceived kinematics of a box lifting action, and use this technique to explore the kinematic cues that affect weight judgment. We find that observers rely most on the duration of the lifting movement to judge weight, and make less use of the durations of the grasp phase, when the box is first gripped, or the place phase, when the box is put down. These findings can be compared to the kinematics of natural box lifting behaviour, where we find that the duration of the grasp component is the best predictor of true box weight. The lack of accord between the optimal cues predicted by the natural behaviour and the cues actually used in the perceptual task has implications for our understanding of action observation in terms of a motor simulation. The differences between perceptual and motor behaviour are evidence against a strong version of the motor simulation hypothesis. PMID:16311765

Vibrotactile grasping force and hand aperture feedback for myoelectric forearm prosthesis users.

PubMed

Witteveen, Heidi J B; Rietman, Hans S; Veltink, Peter H

2015-06-01

User feedback about grasping force and hand aperture is very important in object handling with myoelectric forearm prostheses but is lacking in current prostheses. Vibrotactile feedback increases the performance of healthy subjects in virtual grasping tasks, but no extensive validation on potential users has been performed. Investigate the performance of upper-limb loss subjects in grasping tasks with vibrotactile stimulation, providing hand aperture, and grasping force feedback. Cross-over trial. A total of 10 subjects with upper-limb loss performed virtual grasping tasks while perceiving vibrotactile feedback. Hand aperture feedback was provided through an array of coin motors and grasping force feedback through a single miniature stimulator or an array of coin motors. Objects with varying sizes and weights had to be grasped by a virtual hand. Percentages correctly applied hand apertures and correct grasping force levels were all higher for the vibrotactile feedback condition compared to the no-feedback condition. With visual feedback, the results were always better compared to the vibrotactile feedback condition. Task durations were comparable for all feedback conditions. Vibrotactile grasping force and hand aperture feedback improves grasping performance of subjects with upper-limb loss. However, it should be investigated whether this is of additional value in daily-life tasks. This study is a first step toward the implementation of sensory vibrotactile feedback for users of myoelectric forearm prostheses. Grasping force feedback is crucial for optimal object handling, and hand aperture feedback is essential for reduction of required visual attention. Grasping performance with feedback is evaluated for the potential users. © The International Society for Prosthetics and Orthotics 2014.

Bicultural Self-Efficacy among College Students: Initial Scale Development and Mental Health Correlates

ERIC Educational Resources Information Center

David, E. J. R.; Okazaki, Sumie; Saw, Anne

2009-01-01

Theory and empirical research suggest that perceived self-efficacy, or one's perceived ability to perform personally significant tasks, is related to individuals' psychological well-being and mental health. Thus, the authors hypothesized that bicultural individuals' perceived ability to function competently in 2 cultures, or perceived bicultural…

Short and long sleep duration and risk of drowsy driving and the role of subjective sleep insufficiency.

PubMed

Maia, Querino; Grandner, Michael A; Findley, James; Gurubhagavatula, Indira

2013-10-01

Experimental sleep restriction increases sleepiness and impairs driving performance. However, it is unclear whether short sleep duration in the general population is associated with drowsy driving. The goal of the present study was to evaluate whether individuals in the general population who obtained sleep of 6h or less are more likely to report drowsy driving, and evaluate the role of perceived sleep sufficiency. Data exploring whether subgroups of short sleepers (those who report the most or least unmet sleep need) show different risk profiles for drowsy driving are limited. From the 2009 Behavioral Risk Factor Surveillance System (N=31,522), we obtained the following self-reported data: (1) sleep duration (≤5, 6, 7, 8, 9, or ≥10 h/night); (2) number of days/week of perceived insufficient sleep; (3) among drivers, yes/no response to: "During the past 30 days, have you ever nodded off or fallen asleep, even just for a brief moment, while driving?" (4) demographics, physical/mental health. Using 7 h/night as reference, logistic regression analyses evaluated whether self-reported sleep duration was associated with drowsy driving. Overall, 3.6% reported drowsy driving. Self-identified short-sleepers reported drowsy driving more often, and long sleepers, less often. Among those who perceived sleep as always insufficient, drowsy driving was reported more often when sleep duration was ≤5 h, 6 h, or ≥10 h. Among those who perceived sleep as always sufficient, drowsy driving was reported more often among ≤5 h and 6h sleepers. Overall, drowsy driving was common, particularly in self-identified short-sleepers as a whole, as well as subgroups based on sleep insufficiency. Copyright © 2013 Elsevier Ltd. All rights reserved.

Time-on-task decrement in vigilance is modulated by inter-individual vulnerability to homeostatic sleep pressure manipulation

PubMed Central

Maire, Micheline; Reichert, Carolin F.; Gabel, Virginie; Viola, Antoine U.; Krebs, Julia; Strobel, Werner; Landolt, Hans-Peter; Bachmann, Valérie; Cajochen, Christian; Schmidt, Christina

2014-01-01

Under sleep loss, vigilance is reduced and attentional failures emerge progressively. It becomes difficult to maintain stable performance over time, leading to growing performance variability (i.e., state instability) in an individual and among subjects. Task duration plays a major role in the maintenance of stable vigilance levels, such that the longer the task, the more likely state instability will be observed. Vulnerability to sleep-loss-dependent performance decrements is highly individual and is also modulated by a polymorphism in the human clock gene PERIOD3 (PER3). By combining two different protocols, we manipulated sleep-wake history by once extending wakefulness for 40 h (high sleep pressure condition) and once by imposing a short sleep-wake cycle by alternating 160 min of wakefulness and 80 min naps (low sleep pressure condition) in a within-subject design. We observed that homozygous carriers of the long repeat allele of PER3 (PER35/5) experienced a greater time-on-task dependent performance decrement (i.e., a steeper increase in the number of lapses) in the Psychomotor Vigilance Task compared to the carriers of the short repeat allele (PER34/4). These genotype-dependent effects disappeared under low sleep pressure conditions, and neither motivation, nor perceived effort accounted for these differences. Our data thus suggest that greater sleep-loss related attentional vulnerability based on the PER3 polymorphism is mirrored by a greater state instability under extended wakefulness in the short compared to the long allele carriers. Our results undermine the importance of time-on-task related aspects when investigating inter-individual differences in sleep loss-induced behavioral vulnerability. PMID:24639634

Expectancy-value theory in persistence of learning effects in schizophrenia: role of task value and perceived competency.

PubMed

Choi, Jimmy; Fiszdon, Joanna M; Medalia, Alice

2010-09-01

Expectancy-value theory, a widely accepted model of motivation, posits that expectations of success on a learning task and the individual value placed on the task are central determinants of motivation to learn. This is supported by research in healthy controls suggesting that beliefs of self-and-content mastery can be so influential they can predict the degree of improvement on challenging cognitive tasks even more so than general cognitive ability. We examined components of expectancy-value theory (perceived competency and task value), along with baseline arithmetic performance and neuropsychological performance, as possible predictors of learning outcome in a sample of 70 outpatients with schizophrenia randomized to 1 of 2 different arithmetic learning conditions and followed up after 3 months. Results indicated that as with nonpsychiatric samples, perceived self-competency for the learning task was significantly related to perceptions of task value attributed to the learning task. Baseline expectations of success predicted persistence of learning on the task at 3-month follow-up, even after accounting for variance attributable to different arithmetic instruction, baseline arithmetic ability, attention, and self-reports of task interest and task value. We also found that expectation of success is a malleable construct, with posttraining improvements persisting at follow-up. These findings support the notion that expectancy-value theory is operative in schizophrenia. Thus, similar to the nonpsychiatric population, treatment benefits may be enhanced and better maintained if remediation programs also focus on perceptions of self-competency for the training tasks. Treatment issues related to instilling self-efficacy in cognitive recovery programs are discussed.

Prevalence and associated factors for thoracic spine pain in the adult working population: a literature review.

PubMed

Briggs, Andrew M; Bragge, Peter; Smith, Anne J; Govil, Dhruv; Straker, Leon M

2009-01-01

Spinal pain is a significant occupational health issue. Whilst neck pain and low back pain have received considerable attention, thoracic spinal pain (TSP) has not. The objective of this study was to systematically identify and report the evidence describing the prevalence and correlates of TSP within occupational groups. This literature review systematically searched for reports of TSP prevalence and associated factors for TSP in working adult cohorts using nine electronic databases. Studies were evaluated for level of evidence and epidemiologic data were narratively synthesised. 52 studies were identified describing 65 cohorts covering manual labourers, office workers, health professionals, manufacturing and industrial workers, drivers, military personnel and performing artists. Prevalence varied with occupational group and time period. One year prevalence of TSP ranged from 3.0-55.0%, with most occupational groups having medians around 30%. Significant odds ratios for individual (concurrent musculoskeletal disorders, exercising, pre-menstrual tension and female gender), general work-related (high work load, high work intensity, perceiving ergonomic problems in the workplace, working in some specialised areas, performing boring/tedious work tasks, certain year levels of study, employment duration, driving specialised vehicles, and a high number of flying hours), physical work-related (manual physiotherapy tasks, climbing stairs and high physical stress) and psychosocial work-related (perceived risk of injury and high mental pressure) factors were reported. The high median prevalence rates suggest TSP may be a significant occupational health problem. The multiple domains of associated factors point to the need for prospective research encompassing these domains to inform targeted occupational interventions.

Perceived intent motivates people to magnify observed harms

PubMed Central

Ames, Daniel L.; Fiske, Susan T.

2015-01-01

Existing moral psychology research commonly explains certain phenomena in terms of a motivation to blame. However, this motivation is not measured directly, but rather is inferred from other measures, such as participants’ judgments of an agent’s blameworthiness. The present paper introduces new methods for assessing this theoretically important motivation, using tools drawn from animal-model research. We test these methods in the context of recent “harm-magnification” research, which shows that people often overestimate the damage caused by intentional (versus unintentional) harms. A preliminary experiment exemplifies this work and also rules out an alternative explanation for earlier harm-magnification results. Exp. 1 asks whether intended harm motivates blame or merely demonstrates the actor’s intrinsic blameworthiness. Consistent with a motivational interpretation, participants freely chose blaming, condemning, and punishing over other appealing tasks in an intentional-harm condition, compared with an unintentional-harm condition. Exp. 2 also measures motivation but with converging indicators of persistence (effort, rate, and duration) in blaming. In addition to their methodological contribution, these studies also illuminate people’s motivational responses to intentional harms. Perceived intent emerges as catalyzing a motivated social cognitive process related to social prediction and control. PMID:25733850

The influence of artificial scotomas on eye movements during visual search.

PubMed

Cornelissen, Frans W; Bruin, Klaas J; Kooijman, Aart C

2005-01-01

Fixation durations are normally adapted to the difficulty of the foveal analysis task. We examine to what extent artificial central and peripheral visual field defects interfere with this adaptation process. Subjects performed a visual search task while their eye movements were registered. The latter were used to drive a real-time gaze-dependent display that was used to create artificial central and peripheral visual field defects. Recorded eye movements were used to determine saccadic amplitude, number of fixations, fixation durations, return saccades, and changes in saccade direction. For central defects, although fixation duration increased with the size of the absolute central scotoma, this increase was too small to keep recognition performance optimal, evident from an associated increase in the rate of return saccades. Providing a relatively small amount of visual information in the central scotoma did substantially reduce subjects' search times but not their fixation durations. Surprisingly, reducing the size of the tunnel also prolonged fixation duration for peripheral defects. This manipulation also decreased the rate of return saccades, suggesting that the fixations were prolonged beyond the duration required by the foveal task. Although we find that adaptation of fixation duration to task difficulty clearly occurs in the presence of artificial scotomas, we also find that such field defects may render the adaptation suboptimal for the task at hand. Thus, visual field defects may not only hinder vision by limiting what the subject sees of the environment but also by limiting the visual system's ability to program efficient eye movements. We speculate this is because of how visual field defects bias the balance between saccade generation and fixation stabilization.

Heuristics of reasoning and analogy in children's visual perspective taking.

PubMed

Yaniv, I; Shatz, M

1990-10-01

We propose that children's reasoning about others' visual perspectives is guided by simple heuristics based on a perceiver's line of sight and salient features of the object met by that line. In 3 experiments employing a 2-perceiver analogy task, children aged 3-6 were generally better able to reproduce a perceiver's perspective if a visual cue in the perceiver's line of sight sufficed to distinguish it from alternatives. Children had greater difficulty when the task hinged on attending to configural cues. Availability of distinctive cues affixed on the objects' sides facilitated solution of the symmetrical orientations. These and several other related findings reported in the literature are traced to children's reliance on heuristics of reasoning.

Siblings in dyads: relationships among perceptions and behavior.

PubMed

Graham-Bermann, S A

1991-06-01

The ways in which middle-childhood siblings perceive themselves as similar or different was assessed with a sample of 40 pairs of 9- to 11-year-old (younger) and 12- to 14-year-old (older) siblings. Each child was interviewed and completed a card sort procedure and a measure of self-competence. Sibling pairs participated in three behavioral tasks coded for cooperation and conflict. Self-ratings, self-perceptions, and sibling behavior were analyzed for their association with the perceived similarity construct. Siblings perceived themselves as being more like one another than did their mothers. Forty-one percent of the variance in their perceived similarity was accounted for by paired self-cooperation ratings, social competence, and behavioral task scores.

Assessing task-technology fit in a PACS upgrade: do users' and developers' appraisals converge?

PubMed

Lepanto, Luigi; Sicotte, Claude; Lehoux, Pascale

2011-12-01

The purpose of this study was to measure users' perceived benefits of a picture archiving and communication system (PACS) upgrade, and compare their responses to those predicted by developers. The Task-Technology Fit (TTF) model served as the theoretical framework to study the relation between TTF, utilization, and perceived benefits. A self-administered survey was distributed to radiologists working in a university hospital undergoing a PACS upgrade. Four variables were measured: impact, utilization, TTF, and perceived net benefits. The radiologists were divided into subgroups according to their utilization profiles. Analysis of variance was performed and the hypotheses were tested with regression analysis. Interviews were conducted with developers involved in the PACS upgrade who were asked to predict impact and TTF. Users identified only a moderate fit between the PACS enhancements and their tasks, while developers predicted a high level of TTF. The combination of a moderate fit and an underestimation of the potential impact of changes in the PACS led to a low score for perceived net benefits. Results varied significantly among user subgroups. Globally, the data support the hypotheses that TTF predicts utilization and perceived net benefits, but not that utilization predicts perceived net benefits. TTF is a valid tool to assess perceived benefits, but it is important to take into account the characteristics of users. In the context of a technology that is rapidly evolving, there needs to be an alignment of what users perceive as a good fit and the functionality developers incorporate into their products.

Manual handling: differences in perceived effort, success rate and kinematics between three different pushing techniques.

PubMed

Varcin, Lynn; Claus, Andrew; van den Hoorn, Wolbert; Hodges, Paul

2015-01-01

This study examined the perceived effort, success rates and kinematics for three push strategies in a simulated lateral patient transfer (horizontal slide). Thirteen healthy subjects (four males) completed three repetition pushing loads of 6, 10 and 14 kg in random order; with a spontaneous push strategy, then with a straight-back bent-knees (squat) strategy and the preparatory pelvic movement ('rockback') strategy in random order. Perceived effort and kinematic parameters measured at the onset of movement and at maximum push excursion were compared between strategies and between loads with repeated measures ANOVA. The spontaneous and 'rockback' strategies achieved the pushing task with less perceived effort across all loads than the squat push (P < 0.001). Only 3/13 participants were successful on all attempts at pushing the 14 kg load using a squat strategy, which contrasted with 12/13 participants when the spontaneous strategy or the 'rockback' strategy was used. Forward movement of the pelvis and forward trunk inclination may be positively associated with lower perceived effort in the push task. Practitioner Summary: In a manual-handling task that simulated a lateral patient transfer (horizontal slide), perceived effort and success rates of three push strategies were compared. A straight-back bent-knees push (squat) strategy demonstrated greater perceived effort and lower success rates than a spontaneous push strategy, or a push strategy with preparatory 'rockback' pelvic movement.

Striving for group agency: threat to personal control increases the attractiveness of agentic groups

PubMed Central

Stollberg, Janine; Fritsche, Immo; Bäcker, Anna

2015-01-01

When their sense of personal control is threatened people try to restore perceived control through the social self. We propose that it is the perceived agency of ingroups that provides the self with a sense of control. In three experiments, we for the first time tested the hypothesis that threat to personal control increases the attractiveness of being part or joining those groups that are perceived as coherent entities engaging in coordinated group goal pursuit (agentic groups) but not of those groups whose agency is perceived to be low. Consistent with this hypothesis we found in Study 1 (N = 93) that threat to personal control increased ingroup identification only with task groups, but not with less agentic types of ingroups that were made salient simultaneously. Furthermore, personal control threat increased a sense of collective control and support within the task group, mediated through task-group identification (indirect effects). Turning to groups people are not (yet) part of, Study 2 (N = 47) showed that personal control threat increased relative attractiveness ratings of small groups as possible future ingroups only when the relative agency of small groups was perceived to be high. Perceived group homogeneity or social power did not moderate the effect. Study 3 (N = 78) replicated the moderating role of perceived group agency for attractiveness ratings of entitative groups, whereas perceived group status did not moderate the effect. These findings extend previous research on group-based control, showing that perceived agency accounts for group-based responses to threatened control. PMID:26074832

Environmental surfaces and the compression of perceived visual space

PubMed Central

Bian, Zheng; Andersen, George J.

2011-01-01

The present study examined whether the compression of perceived visual space varies according to the type of environmental surface being viewed. To examine this issue, observers made exocentric distance judgments when viewing simulated 3D scenes. In 4 experiments, observers viewed ground and ceiling surfaces and performed either an L-shaped matching task (Experiments 1, 3, and 4) or a bisection task (Experiment 2). Overall, we found considerable compression of perceived exocentric distance on both ground and ceiling surfaces. However, the perceived exocentric distance was less compressed on a ground surface than on a ceiling surface. In addition, this ground surface advantage did not vary systematically as a function of the distance in the scene. These results suggest that the perceived visual space when viewing a ground surface is less compressed than the perceived visual space when viewing a ceiling surface and that the perceived layout of a surface varies as a function of the type of the surface. PMID:21669858

Perceived facial expressions of emotion as motivational incentives: evidence from a differential implicit learning paradigm.

PubMed

Schultheiss, Oliver C; Pang, Joyce S; Torges, Cynthia M; Wirth, Michelle M; Treynor, Wendy; Derryberry, Douglas

2005-03-01

Participants (N = 216) were administered a differential implicit learning task during which they were trained and tested on 3 maximally distinct 2nd-order visuomotor sequences, with sequence color serving as discriminative stimulus. During training, 1 sequence each was followed by an emotional face, a neutral face, and no face, using backward masking. Emotion (joy, surprise, anger), face gender, and exposure duration (12 ms, 209 ms) were varied between participants; implicit motives were assessed with a picture-story exercise. For power-motivated individuals, low-dominance facial expressions enhanced and high-dominance expressions impaired learning. For affiliation-motivated individuals, learning was impaired in the context of hostile faces. These findings did not depend on explicit learning of fixed sequences or on awareness of sequence-face contingencies. Copyright 2005 APA, all rights reserved.

Assessing Cortisol Reactivity to a Linguistic Task as a Marker of Stress in Individuals with Left-Hemisphere Stroke and Aphasia

ERIC Educational Resources Information Center

Laures-Gore, Jacqueline; Heim, Christine M.; Hsu, Yu-Sheng

2007-01-01

Purpose: In this study, the authors explore a method of measuring physiologic and perceived stress in individuals with aphasia by investigating salivary cortisol reactivity and subjectively perceived stress in response to a standardized linguistic task. Method: Fifteen individuals with aphasia and 15 age-matched healthy controls participated in a…

Larger Stimuli Require Longer Processing Time for Perception.

PubMed

Kanai, Ryota; Dalmaijer, Edwin S; Sherman, Maxine T; Kawakita, Genji; Paffen, Chris L E

2017-05-01

The time it takes for a stimulus to reach awareness is often assessed by measuring reaction times (RTs) or by a temporal order judgement (TOJ) task in which perceived timing is compared against a reference stimulus. Dissociations of RT and TOJ have been reported earlier in which increases in stimulus intensity such as luminance intensity results in a decrease of RT, whereas perceived perceptual latency in a TOJ task is affected to a lesser degree. Here, we report that a simple manipulation of stimulus size has stronger effects on perceptual latency measured by TOJ than on motor latency measured by RT tasks. When participants were asked to respond to the appearance of a simple stimulus such as a luminance blob, the perceptual latency measured against a standard reference stimulus was up to 40 ms longer for a larger stimulus. In other words, the smaller stimulus was perceived to occur earlier than the larger one. RT on the other hand was hardly affected by size. The TOJ results were further replicated in a simultaneity judgement task, suggesting that the effects of size are not due to TOJ-specific response biases but more likely reflect an effect on perceived timing.

Working memory in Farsi-speaking children with normal development and cochlear implant.

PubMed

Soleymani, Zahra; Amidfar, Meysam; Dadgar, Hooshang; Jalaie, Shohre

2014-04-01

Working memory has an important role in language acquisition and development of cognition skills. The ability of encoding, storage and retrieval of phonological codes, as activities of working memory, acquired by audition sense. Children with cochlear implant experience a period that they are not able to perceive sounds. In order to assess the effect of hearing on working memory, we investigated working memory as a cognition skill in children with normal development and cochlear implant. Fifty students with normal hearing and 50 students with cochlear implant aged 5-7 years participated in this study. Children educated in the preschool, the first and second grades. Children with normal development were matched based on age, gender, and grade of education with cochlear implant. Two components of working memory including phonological loop and central executive were compared between two groups. Phonological loop assessed by nonword repetition task and forward digit span. To assess central executive component backward digit span was used. The developmental trend was studied in children with normal development and cochlear implant as well. The effect of age at implantation in children with cochlear implants on components of working memory was investigated. There are significant differences between children with normal development and cochlear implant in all tasks that assess working memory (p < 0.001). The children's age at implantation was negatively correlated with all tasks (p < 0.001). In contrast, duration of usage of cochlear implant set was positively correlated with all tasks (p < 0.001). The comparison of working memory between different grades showed significant differences both in children with normal development and in children with cochlear implant (p < 0.05). These results implied that children with cochlear implant may experience difficulties in working memory. Therefore, these children have problems in encoding, practicing, and repeating phonological units. The results also suggested working memory develops when the child grows up. In cochlear implant children, with decreasing age at implantation and increasing their experience in perceiving sound, working memory skills improved. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Perceived duration decreases with increasing eccentricity.

PubMed

Kliegl, Katrin M; Huckauf, Anke

2014-07-01

Previous studies examining the influence of stimulus location on temporal perception yield inhomogeneous and contradicting results. Therefore, the aim of the present study is to soundly examine the effect of stimulus eccentricity. In a series of five experiments, subjects compared the duration of foveal disks to disks presented at different retinal eccentricities on the horizontal meridian. The results show that the perceived duration of a visual stimulus declines with increasing eccentricity. The effect was replicated with various stimulus orders (Experiments 1-3), as well as with cortically magnified stimuli (Experiments 4-5), ruling out that the effect was merely caused by different cortical representation sizes. The apparent decreasing duration of stimuli with increasing eccentricity is discussed with respect to current models of time perception, the possible influence of visual attention and respective underlying physiological characteristics of the visual system. Copyright © 2014 Elsevier B.V. All rights reserved.

Do Differences in Levels, Types, and Duration of Muscle Contraction Have an Effect on the Degree of Post-exercise Depression?

PubMed

Miyaguchi, Shota; Kojima, Sho; Kirimoto, Hikari; Tamaki, Hiroyuki; Onishi, Hideaki

2016-01-01

We conducted two experiments to determine how differences in muscle contraction levels, muscle contraction types, and movement duration affect degree of post-exercise depression (PED) after non-exhaustive, repetitive finger movement. Twelve healthy participants performed repetitive abduction movements of the right index finger at 2 Hz. In experiment 1, we examined the effects of muscle contraction levels at 10, 20, and 30% maximum voluntary contraction and the effects of muscle contraction types at isotonic and isometric contraction. In experiment 2, we examined the effects of movement duration at 2 and 6 min. Motor-evoked potentials (MEPs) were recorded from the right first dorsal interosseous muscle before movement tasks and 1-10 min after movement tasks. MEP amplitudes after isotonic contraction tasks were significantly smaller than those after isometric contraction tasks and decreased with increasing contraction levels, but were independent of movement duration. This study demonstrated that the degree of PED after non-exhaustive repetitive finger movement depended on muscle contraction levels and types. Thus, the degree of PED may depend on the levels of activity in the motor cortex during a movement task. This knowledge will aid in the design of rehabilitation protocols.

Testing the distinctiveness of visual imagery and motor imagery in a reach paradigm.

PubMed

Gabbard, Carl; Ammar, Diala; Cordova, Alberto

2009-01-01

We examined the distinctiveness of motor imagery (MI) and visual imagery (VI) in the context of perceived reachability. The aim was to explore the notion that the two visual modes have distinctive processing properties tied to the two-visual-system hypothesis. The experiment included an interference tactic whereby participants completed two tasks at the same time: a visual or motor-interference task combined with a MI or VI-reaching task. We expected increased error would occur when the imaged task and the interference task were matched (e.g., MI with the motor task), suggesting an association based on the assumption that the two tasks were in competition for space on the same processing pathway. Alternatively, if there were no differences, dissociation could be inferred. Significant increases in the number of errors were found when the modalities for the imaged (both MI and VI) task and the interference task were matched. Therefore, it appears that MI and VI in the context of perceived reachability recruit different processing mechanisms.

Risk of predation makes foragers less choosy about their food.

PubMed

Charalabidis, Alice; Dechaume-Moncharmont, François-Xavier; Petit, Sandrine; Bohan, David A

2017-01-01

Animals foraging in the wild have to balance speed of decision making and accuracy of assessment of a food item's quality. If resource quality is important for maximizing fitness, then the duration of decision making may be in conflict with other crucial and time consuming tasks, such as anti-predator behaviours or competition monitoring. Individuals facing the risk of predation and/or competition should adjust the duration of decision making and, as a consequence, their level of choosiness for resources. When exposed to predation, the forager could either maintain its level of choosiness for food items but accept a reduction in the amount of food items consumed or it could reduce its level of choosiness and accept all prey items encountered. Under competition risk, individuals are expected to reduce their level of choosiness as slow decision making exposes individuals to a higher risk of opportunity costs. To test these predictions, the level of choosiness of a seed-eating carabid beetle, Harpalus affinis, was examined under 4 different experimental conditions of risk: i) predation risk; ii) intraspecific competition; iii) interspecific competition; and, iv) control. All the risks were simulated using chemical cues from individual conspecifics or beetles of different species that are predatory or granivorous. Our results show that when foraging under the risk of predation, H. affinis individuals significantly reduce their level of choosiness for seeds. Reductions in level of choosiness for food items might serve as a sensible strategy to reduce both the total duration of a foraging task and the cognitive load of the food quality assessment. No significant differences were observed when individuals were exposed to competition cues. Competition, (i.e opportunity cost) may not be perceived as risk high enough to induce changes in the level of choosiness. Our results suggest that considering the amount of items consumed, alone, would be a misleading metric when assessing individual response to a risk of predation. Foraging studies should therefore also take in account the decision making process.

The perception of FM sweeps by Chinese and English listeners.

PubMed

Luo, Huan; Boemio, Anthony; Gordon, Michael; Poeppel, David

2007-02-01

Frequency-modulated (FM) signals are an integral acoustic component of ecologically natural sounds and are analyzed effectively in the auditory systems of humans and animals. Linearly frequency-modulated tone sweeps were used here to evaluate two questions. First, how rapid a sweep can listeners accurately perceive? Second, is there an effect of native language insofar as the language (phonology) is differentially associated with processing of FM signals? Speakers of English and Mandarin Chinese were tested to evaluate whether being a speaker of a tone language altered the perceptual identification of non-speech tone sweeps. In two psychophysical studies, we demonstrate that Chinese subjects perform better than English subjects in FM direction identification, but not in an FM discrimination task, in which English and Chinese speakers show similar detection thresholds of approximately 20 ms duration. We suggest that the better FM direction identification in Chinese subjects is related to their experience with FM direction analysis in the tone-language environment, even though supra-segmental tonal variation occurs over a longer time scale. Furthermore, the observed common discrimination temporal threshold across two language groups supports the conjecture that processing auditory signals at durations of approximately 20 ms constitutes a fundamental auditory perceptual threshold.

Comparison of work rates, energy expenditure, and perceived exertion during a 1-h vacuuming task with a backpack vacuum cleaner and an upright vacuum cleaner.

PubMed

Mengelkoch, Larry J; Clark, Kirby

2006-03-01

The purpose of this study was to evaluate two types of industrial vacuum cleaners, in terms of cleaning rates, energy expenditure, and perceived exertion. Twelve industrial cleaners (six males and six females, age 28-39 yr) performed two 1-h vacuuming tasks with an upright vacuum cleaner (UVC) and a backpack vacuum cleaner (BPVC). Measures for oxygen uptake (VO2) and ratings of perceived exertion (RPE) were collected continuously during the 1-h vacuuming tasks. Cleaning rates for the UVC and BPVC were 7.23 and 14.98 m2min(-1), respectively. On a separate day subjects performed a maximal treadmill exercise test to determine their maximal aerobic capacity (peak VO2). Average absolute energy costs (in Metabolic equivalents), relative energy costs of the vacuum task compared to the subjects' maximal aerobic capacity (% peak VO2), and RPE responses for the 1-h vacuuming tasks were similar between vacuum cleaners, but % peak VO2 and RPE values differed between genders. These results indicate that the BPVC was more efficient than the UVC. With the BPVC, experienced workers vacuumed at a cleaning rate 2.07 times greater than the UVC and had similar levels of energy expenditure and perceived effort, compared to the slower cleaning rate with the UVC.

Changes in disability following physical therapy intervention for patients with low back pain: dependence on symptom duration.

PubMed

Badke, Mary Beth; Boissonnault, William G

2006-06-01

To assess the impact of symptom duration on functional outcome, functional improvement, pain, and patient perception of recovery after a physical therapy (PT) program for low back pain (LBP) and to determine what variables are significantly associated with improved function. Retrospective case series. Outpatient setting at a tertiary care facility. Patients (N=130) who were seen for PT between June 2003 and November 2004. A customized rehabilitation program was developed for each patient based on examination findings and included a combination of the following interventions: mobilization/manipulation, flexibility exercises, strengthening exercises, endurance exercises, massage techniques, and heat and cold modalities. Functional outcome, functional improvement, perceived pain, and perceived improvement scores in the CareConnections Outcomes System (formerly TAOS) database. Persons whose symptom duration was greater than 6 months had significantly less functional improvement than persons whose symptom duration was less than 1 month. The median percentage improvement score for perceived recovery was also significantly lower for the chronic group than for the acute group. There was no significant difference in the percentage decrease in pain among the acute, subacute, and chronic groups. In regression analyses, a model with age (P=.001), symptom duration (P=.002), and inclusion of strengthening, flexibility, and mobilization and manipulation exercises (P=.001) fit the data well and explained 55.5% of the variance in functional improvement score for all 3 groups combined. Patients showed improvements in function following a rehabilitation program for LBP. The functional improvement score is influenced by age, symptom duration, and inclusion of mobilization/manipulation and strengthening and flexibility exercises.

Relationships between recall of perceived exertion and blood lactate concentration in a judo competition.

PubMed

Serrano, M A; Salvador, A; González-Bono, E G; Sanchís, C; Suay, F

2001-06-01

Relationships between perceived exertion and blood lactate have usually been studied in laboratory or training contexts but not in competition, the most important setting in which sports performance is evaluated. The purpose of this study was to examine the relationships between psychological and physiological indices of the physical effort in a competition setting, taking into account the duration of effort. For this, we employed two Ratings of Perceived Exertion (RPE and CR-10) and lactic acid plasma concentration as a biological marker of the effort performed. 13 male judo fighters who participated in a sports club competition provided capillary blood samples to assay lactate concentrations and indicated on scale their Recall of Perceived Exertion in the total competition and again in just the Last Fight to compare the usefulness of RPE and CR-10 in assessing discrete bouts of effort and a whole session. Analysis showed that perceived exertion or the effort made during the whole competition was positively and significantly related to maximal lactate concentration and lactate increase in competition, thus extending the validity of this scale to sports contests. The Recall of Perceived Exertion scores were not significantly correlated with the duration of effort.

Causal relationships of sport and exercise involvement with goal orientations, perceived competence and intrinsic motivation in physical education: a longitudinal study.

PubMed

Papaioannou, Athanasios; Bebetsos, Evaggelos; Theodorakis, Yannis; Christodoulidis, Triantafyllos; Kouli, Olga

2006-04-01

Little information exists about the causal relationships of sport and exercise participation with goal orientations, perceived athletic competence and intrinsic motivation in physical education. A longitudinal study was conducted involving 882 Greek students who completed questionnaires on three occasions: 3 - 5 weeks into the academic year, 3 - 6 weeks before the end of the academic year, and 7 months later. The data were analysed using structural equation models, controlling for age. Task orientation and intrinsic motivation in physical education at the beginning of the academic year predicted sport and exercise participation 7 and 14 months later. Perceived athletic competence both at the beginning and end of the academic year predicted sport and exercise participation 7 and 14 months later, while ego orientation did not predict sport and exercise involvement at either time. Previous sport and exercise participation had positive effects on task orientation and perceived athletic competence 3 - 6 weeks before the end of the academic year and predicted all cognitive-affective constructs 7 months later. These results imply that the cultivation of task orientation, intrinsic motivation in physical education and perceived athletic competence will help to promote sport and exercise participation in adolescence.

Racial differences in self-reports of short sleep duration in an urban-dwelling environment.

PubMed

Gamaldo, Alyssa A; McNeely, Jessica M; Shah, Mauli T; Evans, Michele K; Zonderman, Alan B

2015-07-01

To explore whether there are differences in sleep duration between blacks and whites residing in similar urban neighborhoods and examine whether the relationship between sleep durations and sociodemographic and/or health indices are consistent for blacks and whites. A total of 1,207 participants from the Healthy Aging in Neighborhoods of Disparities across the Life Span study (age: mean = 47, standard deviation = 8.74). Sleep duration was assessed by a self-report of hours of nightly sleep in the past month. Sociodemographic measures included age, sex, education, poverty status, and perceived neighborhood disorder. Health status was assessed using measures of vigilance, depression, perceived stress, coronary artery disease, diabetes, blood pressure, and inflammation. There were no significant racial group differences in sleep duration. Whites, however, were more likely than blacks to report sleep durations of <6/6-7 hr compared with >7 hr with increasing stress and education levels. Blacks were more likely than whites to report short sleep durations (i.e., 6-7 hr vs. >7 hr of sleep) with increasing inflammation levels. Although racial disparities in sleep duration are minimized when the environment is equivalent between blacks and whites, the underlying demographic and health explanations for short sleep durations may vary between whites and blacks. Published by Oxford University Press on behalf of the Gerontological Society of America 2013.

Stop identity cue as a cue to language identity

NASA Astrophysics Data System (ADS)

Castonguay, Paula Lisa

The purpose of the present study was to determine whether language membership could potentially be cued by the acoustic-phonetic detail of word-initial stops and retained all the way through the process of lexical access to aid in language identification. Of particular interest were language-specific differences in CE and CF word-initial stops. Experiment 1 consisted of an interlingual homophone production task. The purpose of this study was to examine how word-initial stop consonants differ in terms of acoustic properties in Canadian English (CE) and Canadian French (CF) interlingual homophones. The analyses from the bilingual speakers in Experiment 1 indicate that bilinguals do produce language-specific differences in CE and CF word-initial stops, and that closure duration, voice onset time, and burst spectral SD may provide cues to language identity in CE and CF stops. Experiment 2 consisted of a Phoneme and Language Categorization task. The purpose of this study was to examine how stop identity cues, such as VOT and closure duration, influence a listener to identify word-initial stop consonants as belonging to Canadian English (CE) or Canadian French (CF). The RTs from the bilingual listeners in this study indicate that bilinguals do perceive language-specific differences in CE and CF word-initial stops, and that voice onset time may provide cues to phoneme and language membership in CE and CF stops. Experiment 3 consisted of a Phonological-Semantic priming task. The purpose of this study was to examine how subphonetic variations, such as changes in the VOT, affect lexical access. The results of Experiment 3 suggest that language-specific cues, such as VOT, affects the composition of the bilingual cohort and that the extent to which English and/or French words are activated is dependent on the language-specific cues present in a word. The findings of this study enhanced our theoretical understanding of lexical structure and lexical access in bilingual speakers. In addition, this study provides further insight on cross-language effects at the subphonetic level.

The Effect of Perceived Injustice on Appraisals of Physical Activity: An Examination of the Mediating Role of Attention Bias to Pain in a Chronic Low Back Pain Sample.

PubMed

Trost, Zina; Van Ryckeghem, Dimitri; Scott, Whitney; Guck, Adam; Vervoort, Tine

2016-11-01

The current study examined the relationship between perceived injustice and attentional bias (AB) toward pain among individuals with chronic low back pain asked to perform and appraise the pain and difficulty of a standardized set of common physical activities. A pictorial dot-probe task assessed AB toward pain stimuli (ie, pain faces cueing pain), after which participants performed the physical tasks. Participants also rated face stimuli in terms of pain, sadness, and anger expression. As hypothesized, perceived injustice was positively associated with AB toward pain stimuli; additionally, perceived injustice and AB were positively associated with appraisals of pain and difficulty. Counter to expectations, AB did not mediate the relationship between perceived injustice and task appraisals, suggesting that AB is insufficient to explain this relationship. Exploratory analyses indicated that participants with higher levels of perceived injustice rated stimulus faces as sadder and angrier; no such differences emerged for pain ratings. To our knowledge, this is the first study to examine the association between perceived injustice and AB toward pain, as well as perceived injustice and in vivo appraisals of common physical activity. Results extend existing literature and suggest that attentional and potential interpretive bias should be considered in future research. This article identifies significant associations between perceived injustice, biased attention to pain, and appraisals of common physical activities among individuals with chronic low back pain. These findings suggest targets for intervention as well as directions for future research regarding individuals with high perceptions of injustice related to pain. Copyright © 2016 American Pain Society. Published by Elsevier Inc. All rights reserved.

Blink activity and task difficulty.

PubMed

Tanaka, Y; Yamaoka, K

1993-08-01

This study investigated the relationship between task difficulty and blink activity, which includes blink rate, blink amplitude, and blink duration. Two kinds of tasks established two levels of difficulty. In Exp. 1, a mental arithmetic task was used to examine the relationship. Analysis showed that blink rate for a difficult task was significantly higher than that for an easier one. In Exp. 2, a letter-search task (hiragana Japanese alphabet) was used while the other conditions were the same as those in Exp. 1; however, the results of this experiment were not influenced by the difficulty of the task. As results indicate that blink rate is related to not only difficulty but also the nature of the task, the nature of the task is probably dependent on a mechanism in information processing. The results for blink amplitude and blink duration showed no systematic change during either experiment.

Task uncertainty and communication during nursing shift handovers.

PubMed

Mayor, Eric; Bangerter, Adrian; Aribot, Myriam

2012-09-01

We explore variations in handover duration and communication in nursing units. We hypothesize that duration per patient is higher in units facing high task uncertainty. We expect both topics and functions of communication to vary depending on task uncertainty. Handovers are changing in modern healthcare organizations, where standardized procedures are increasingly advocated for efficiency and reliability reasons. However, redesign of handover should take environmental contingencies of different clinical unit types into account. An important contingency in institutions is task uncertainty, which may affect how communicative routines like handover are accomplished. Nurse unit managers of 80 care units in 18 hospitals were interviewed in 2008 about topics and functions of handover communication and duration in their unit. Interviews were content-analysed. Clinical units were classified into a theory-based typology (unit type) that gradually increases on task uncertainty. Quantitative analyses were performed. Unit type affected resource allocation. Unit types facing higher uncertainty had higher handover duration per patient. As expected, unit type also affected communication content. Clinical units facing higher uncertainty discussed fewer topics, discussing treatment and care and organization of work less frequently. Finally, unit type affected functions of handover: sharing emotions was less often mentioned in unit types facing higher uncertainty. Task uncertainty and its relationship with functions and topics of handover should be taken into account during the design of handover procedures. © 2011 Blackwell Publishing Ltd.

Predicting physiological capacity of human load carriage - a review.

PubMed

Drain, Jace; Billing, Daniel; Neesham-Smith, Daniel; Aisbett, Brad

2016-01-01

This review article aims to evaluate a proposed maximum acceptable work duration model for load carriage tasks. It is contended that this concept has particular relevance to physically demanding occupations such as military and firefighting. Personnel in these occupations are often required to perform very physically demanding tasks, over varying time periods, often involving load carriage. Previous research has investigated concepts related to physiological workload limits in occupational settings (e.g. industrial). Evidence suggests however, that existing (unloaded) workload guidelines are not appropriate for load carriage tasks. The utility of this model warrants further work to enable prediction of load carriage durations across a range of functional workloads for physically demanding occupations. If the maximum duration for which personnel can physiologically sustain a load carriage task could be accurately predicted, commanders and supervisors could better plan for and manage tasks to ensure operational imperatives were met whilst minimising health risks for their workers. Copyright © 2015 Elsevier Ltd and The Ergonomics Society. All rights reserved.

The Impact of Precaution and Practice on the Performance of a Risky Motor Task

PubMed Central

Keren, Hila; Boyer, Pascal; Mort, Joel; Eilam, David

2013-01-01

The association between threat perception and motor execution, mediated by evolved precaution systems, often results in ritual-like behavior, including many idiosyncratic acts that seem irrelevant to the task at hand. This study tested the hypothesis that threat-detection during performance of a risky motor task would result in idiosyncratic activity that is not necessary for task completion. We asked biology students to follow a particular set of instructions in mixing three solutions labeled “bio-hazardous” and then repeat this operation with “non-hazardous” substances (or vice versa). We observed a longer duration of the overall performance, a greater repertoire of acts, longer maximal act duration, and longer mean duration of acts in the “risky” task when it was performed before the “non-risky” task. Some, but not all, of these differences were eliminated when a “non-risky” task preceded the “risky” one. The increased performance of idiosyncratic unnecessary activity is in accordance with the working hypothesis of the present study: ritualized idiosyncratic activities are performed in response to a real or illusionary threat, as a means to alleviate anxiety. PMID:25379241

Human haptic perception is interrupted by explorative stops of milliseconds

PubMed Central

Grunwald, Martin; Muniyandi, Manivannan; Kim, Hyun; Kim, Jung; Krause, Frank; Mueller, Stephanie; Srinivasan, Mandayam A.

2014-01-01

Introduction: The explorative scanning movements of the hands have been compared to those of the eyes. The visual process is known to be composed of alternating phases of saccadic eye movements and fixation pauses. Descriptive results suggest that during the haptic exploration of objects short movement pauses occur as well. The goal of the present study was to detect these “explorative stops” (ES) during one-handed and two-handed haptic explorations of various objects and patterns, and to measure their duration. Additionally, the associations between the following variables were analyzed: (a) between mean exploration time and duration of ES, (b) between certain stimulus features and ES frequency, and (c) the duration of ES during the course of exploration. Methods: Five different Experiments were used. The first two Experiments were classical recognition tasks of unknown haptic stimuli (A) and of common objects (B). In Experiment C space-position information of angle legs had to be perceived and reproduced. For Experiments D and E the PHANToM haptic device was used for the exploration of virtual (D) and real (E) sunken reliefs. Results: In each Experiment we observed explorative stops of different average durations. For Experiment A: 329.50 ms, Experiment B: 67.47 ms, Experiment C: 189.92 ms, Experiment D: 186.17 ms and Experiment E: 140.02 ms. Significant correlations were observed between exploration time and the duration of the ES. Also, ES occurred more frequently, but not exclusively, at defined stimulus features like corners, curves and the endpoints of lines. However, explorative stops do not occur every time a stimulus feature is explored. Conclusions: We assume that ES are a general aspect of human haptic exploration processes. We have tried to interpret the occurrence and duration of ES with respect to the Hypotheses-Rebuild-Model and the Limited Capacity Control System theory. PMID:24782797

Effects of Short- and Long-Duration Space Flight on Neuromuscular Function

NASA Technical Reports Server (NTRS)

Buxton, Roxanne E.; Spiering, Barry A.; Ryder, Jeffrey W.; Ploutz-Snyder, Lori L.; Bloomberg, Jacob J.

2010-01-01

The Functional Task Tests (FTT) is an interdisciplinary study designed to correlate the changes in functional tasks (such as emergency egress, ladder climbing, and hatch opening) with changes in neuromuscular, cardiovascular, and sensorimotor function. One aspect of the FTT, the neuromuscular function test, is used to investigate the neuromuscular component underlying changes in the ability of astronauts to perform functional tasks (representative of critical mission tasks) safely and quickly after flight. PURPOSE: To describe neuromuscular function after short- and long-duration space flight. METHODS: To date, 5 crewmembers on short-duration (10- to 15-day) missions and 3 on long-duration missions have participated. Crewmembers were assessed 30 days before flight, on landing day (short-duration subjects only) and 1, 6, and 30 days after landing. The interpolated twitch technique, which utilizes a combination of maximal voluntary contractions and electrically evoked contractions, was used to assess the maximal voluntary isometric force (MIF) and central activation capacity of the knee extensors. Leg-press and bench-press devices were used to assess MIF and maximal dynamic power of the lower and upper body respectively. Specifically, power was measured during concentric-only ballistic throws of the leg-press sled and bench-press bar loaded to 40% and 30% of MIF respectively. RESULTS: Data are currently being collected from both Shuttle and ISS crewmembers. Emerging data indicate that measures of knee extensor muscle function are decreased with long-duration flight. DISCUSSION: The relationships between flight duration, neural drive, and muscle performance are of particular interest. Ongoing research will add to the current sample size and will focus on defining changes in muscle performance measures after long-duration space flight.

The Effect of Interruption Duration and Demand on Resuming Suspended Goals

ERIC Educational Resources Information Center

Monk, Christopher A.; Trafton, J. Gregory; Boehm-Davis, Deborah A.

2008-01-01

The time to resume task goals after an interruption varied depending on the duration and cognitive demand of interruptions, as predicted by the memory for goals model (Altmann & Trafton, 2002). Three experiments using an interleaved tasks interruption paradigm showed that longer and more demanding interruptions led to longer resumption times in a…

HRP Integrated Research Plan Analysis

NASA Technical Reports Server (NTRS)

Elliott, Todd

2009-01-01

The charts, that are the totality of this document, presents tasks, duration of the tasks, the start and finish of the tasks, and subtasks. Also presented are PERT charts that display the beginning, external milestones, and end points for the tasks, and sub tasks.

Effects of imperfect automation and individual differences on concurrent performance of military and robotics tasks in a simulated multitasking environment.

PubMed

Chen, J Y C; Terrence, P I

2009-08-01

This study investigated the performance and workload of the combined position of gunner and robotics operator in a simulated military multitasking environment. Specifically, the study investigated how aided target recognition (AiTR) capabilities for the gunnery task with imperfect reliability (false-alarm-prone vs. miss-prone) might affect the concurrent robotics and communication tasks. Additionally, the study examined whether performance was affected by individual differences in spatial ability and attentional control. Results showed that when the robotics task was simply monitoring the video, participants had the best performance in their gunnery and communication tasks and the lowest perceived workload, compared with the other robotics tasking conditions. There was a strong interaction between the type of AiTR unreliability and participants' perceived attentional control. Overall, for participants with higher perceived attentional control, false-alarm-prone alerts were more detrimental; for low attentional control participants, conversely, miss-prone automation was more harmful. Low spatial ability participants preferred visual cueing and high spatial ability participants favoured tactile cueing. Potential applications of the findings include personnel selection for robotics operation, robotics user interface designs and training development. The present results will provide further understanding of the interplays among automation reliability, multitasking performance and individual differences in military tasking environments. These results will also facilitate the implementation of robots in military settings and will provide useful data to military system designs.

Perceiving patterns of play in dynamic sport tasks: investigating the essential information underlying skilled performance.

PubMed

Willams, A Mark; Hodges, Nicola J; North, Jamie S; Barton, Gabor

2006-01-01

The perceptual-cognitive information used to support pattern-recognition skill in soccer was examined. In experiment 1, skilled players were quicker and more accurate than less-skilled players at recognising familiar and unfamiliar soccer action sequences presented on film. In experiment 2, these action sequences were converted into point-light displays, with superficial display features removed and the positions of players and the relational information between them made more salient. Skilled players were more accurate than less-skilled players in recognising sequences presented in point-light form, implying that each pattern of play can be defined by the unique relations between players. In experiment 3, various offensive and defensive players were occluded for the duration of each trial in an attempt to identify the most important sources of information underpinning successful performance. A decrease in response accuracy was observed under occluded compared with non-occluded conditions and the expertise effect was no longer observed. The relational information between certain key players, team-mates and their defensive counterparts may provide the essential information for effective pattern-recognition skill in soccer. Structural feature analysis, temporal phase relations, and knowledge-based information are effectively integrated to facilitate pattern recognition in dynamic sport tasks.

Sleep duration and RSA suppression as predictors of internalizing and externalizing behaviors

PubMed Central

Cho, Sunghye; Philbrook, Lauren E.; Davis, Elizabeth L.; Buss, Kristin A.

2017-01-01

Although the conceptual interplay among the biological and clinical features of sleep, arousal, and emotion regulation has been noted, little is understood about how indices of sleep duration and parasympathetic reactivity operate jointly to predict adjustment in early childhood. Using a sample of 123 toddlers, the present study examined sleep duration and RSA reactivity as predictors of internalizing and externalizing behaviors. Parents reported on children’s sleep duration and adjustment. RSA reactivity was assessed via children’s responses to fear-eliciting stimuli and an inhibitory control challenge. Findings demonstrated that greater RSA suppression to both types of tasks in combination with longer sleep duration was concurrently associated with less internalizing. In contrast, greater RSA augmentation to an inhibitory control task in the context of shorter sleep duration predicted more externalizing 1 year later. The significance of duration of toddlers’ sleep as well as the context in which physiological regulatory difficulties occurs is discussed. PMID:27577700

The effects of military body armour on the lower back and knee mechanics during toe-touch and two-legged squat tasks.

PubMed

Phillips, Megan; Bazrgari, Babak; Shapiro, Robert

2015-01-01

While effective in the prevention of otherwise lethal injuries, military body armour (BA) has been suggested to reduce warfighter's performance and increase injury-related musculoskeletal conditions. Providing the significant role of joint biomechanics in both performance and risk of injury, the immediate and prolonged effects of wearing BA on biomechanics of the lower back and knee during toe-touch (TT) and two-legged squat (TLS) tasks were investigated. The immediate effects of BA were an increase of >40 ms (p ≤ 0.02) in flexion duration of the dominant joint and an ∼1 s (p ≤ 0.02) increase in overall task duration as well as an ∼18% (p = 0.03) decrease in the lumbopelvic rhythm ratio near the mid-range of trunk flexion. In general the prolonged duration of wearing BA (i.e. 45 min of walking) was not found to cause more changes in our measures than walking without BA. The effects of wearing military BA on biomechanics of the lower back and knee during TT and TLS tasks were investigated. The immediate effects of BA were increased flexion duration, increased overall trial duration and decreased lumbopelvic rhythm near the mid-range of trunk flexion.

Linking melodic expectation to expressive performance timing and perceived musical tension.

PubMed

Gingras, Bruno; Pearce, Marcus T; Goodchild, Meghan; Dean, Roger T; Wiggins, Geraint; McAdams, Stephen

2016-04-01

This research explored the relations between the predictability of musical structure, expressive timing in performance, and listeners' perceived musical tension. Studies analyzing the influence of expressive timing on listeners' affective responses have been constrained by the fact that, in most pieces, the notated durations limit performers' interpretive freedom. To circumvent this issue, we focused on the unmeasured prelude, a semi-improvisatory genre without notated durations. In Experiment 1, 12 professional harpsichordists recorded an unmeasured prelude on a harpsichord equipped with a MIDI console. Melodic expectation was assessed using a probabilistic model (IDyOM [Information Dynamics of Music]) whose expectations have been previously shown to match closely those of human listeners. Performance timing information was extracted from the MIDI data using a score-performance matching algorithm. Time-series analyses showed that, in a piece with unspecified note durations, the predictability of melodic structure measurably influenced tempo fluctuations in performance. In Experiment 2, another 10 harpsichordists, 20 nonharpsichordist musicians, and 20 nonmusicians listened to the recordings from Experiment 1 and rated the perceived tension continuously. Granger causality analyses were conducted to investigate predictive relations among melodic expectation, expressive timing, and perceived tension. Although melodic expectation, as modeled by IDyOM, modestly predicted perceived tension for all participant groups, neither of its components, information content or entropy, was Granger causal. In contrast, expressive timing was a strong predictor and was Granger causal. However, because melodic expectation was also predictive of expressive timing, our results outline a complete chain of influence from predictability of melodic structure via expressive performance timing to perceived musical tension. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

Use of Perceive, Recall, Plan, Perform Stage Two Cognitive Task Analysis for Students with Autism and Intellectual Disability: The Impact of a Sensory Activity Schedule

ERIC Educational Resources Information Center

Mills, Caroline; Chapparo, Christine

2017-01-01

The aim of this study was to determine the impact of a classroom sensory activity schedule (SAS) on cognitive strategy use during task performance. This work studies a single-system AB research design with seven students with autism and intellectual disability. Repeated measures using the Perceive, Recall, Plan and Perform (PRPP) Cognitive Task…

Musical agency reduces perceived exertion during strenuous physical performance

PubMed Central

Fritz, Thomas Hans; Hardikar, Samyogita; Demoucron, Matthias; Niessen, Margot; Demey, Michiel; Giot, Olivier; Li, Yongming; Haynes, John-Dylan; Villringer, Arno; Leman, Marc

2013-01-01

Music is known to be capable of reducing perceived exertion during strenuous physical activity. The current interpretation of this modulating effect of music is that music may be perceived as a diversion from unpleasant proprioceptive sensations that go along with exhaustion. Here we investigated the effects of music on perceived exertion during a physically strenuous task, varying musical agency, a task that relies on the experience of body proprioception, rather than simply diverting from it. For this we measured psychologically indicated exertion during physical workout with and without musical agency while simultaneously acquiring metabolic values with spirometry. Results showed that musical agency significantly decreased perceived exertion during workout, indicating that musical agency may actually facilitate physically strenuous activities. This indicates that the positive effect of music on perceived exertion cannot always be explained by an effect of diversion from proprioceptive feedback. Furthermore, this finding suggests that the down-modulating effect of musical agency on perceived exertion may be a previously unacknowledged driving force for the development of music in humans: making music makes strenuous physical activities less exhausting. PMID:24127588

Musical agency reduces perceived exertion during strenuous physical performance.

PubMed

Fritz, Thomas Hans; Hardikar, Samyogita; Demoucron, Matthias; Niessen, Margot; Demey, Michiel; Giot, Olivier; Li, Yongming; Haynes, John-Dylan; Villringer, Arno; Leman, Marc

2013-10-29

Music is known to be capable of reducing perceived exertion during strenuous physical activity. The current interpretation of this modulating effect of music is that music may be perceived as a diversion from unpleasant proprioceptive sensations that go along with exhaustion. Here we investigated the effects of music on perceived exertion during a physically strenuous task, varying musical agency, a task that relies on the experience of body proprioception, rather than simply diverting from it. For this we measured psychologically indicated exertion during physical workout with and without musical agency while simultaneously acquiring metabolic values with spirometry. Results showed that musical agency significantly decreased perceived exertion during workout, indicating that musical agency may actually facilitate physically strenuous activities. This indicates that the positive effect of music on perceived exertion cannot always be explained by an effect of diversion from proprioceptive feedback. Furthermore, this finding suggests that the down-modulating effect of musical agency on perceived exertion may be a previously unacknowledged driving force for the development of music in humans: making music makes strenuous physical activities less exhausting.

The effect of slightly warm temperature on work performance and comfort in open-plan offices - a laboratory study.

PubMed

Maula, H; Hongisto, V; Östman, L; Haapakangas, A; Koskela, H; Hyönä, J

2016-04-01

The aim of the study was to determine the effect of a temperature of 29°C on performance in tasks involving different cognitive demands and to assess the effect on perceived performance, subjective workload, thermal comfort, perceived working conditions, cognitive fatigue, and somatic symptoms in a laboratory with realistic office environment. A comparison was made with a temperature of 23°C. Performance was measured on the basis of six different tasks that reflect different stages of cognitive performance. Thirty-three students participated in the experiment. The exposure time was 3.5 h in both thermal conditions. Performance was negatively affected by slightly warm temperature in the N-back working memory task. Temperature had no effect on performance in other tasks focusing on psychomotor, working memory, attention, or long-term memory capabilities. Temperature had no effect on perceived performance. However, slightly warm temperature caused concentration difficulties. Throat symptoms were found to increase over time at 29°C, but no temporal change was seen at 23°C. No effect of temperature on other symptoms was found. As expected, the differences in thermal comfort were significant. Women perceived a temperature of 23°C colder than men. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

The Whorfian time warp: Representing duration through the language hourglass.

PubMed

Bylund, Emanuel; Athanasopoulos, Panos

2017-07-01

How do humans construct their mental representations of the passage of time? The universalist account claims that abstract concepts like time are universal across humans. In contrast, the linguistic relativity hypothesis holds that speakers of different languages represent duration differently. The precise impact of language on duration representation is, however, unknown. Here, we show that language can have a powerful role in transforming humans' psychophysical experience of time. Contrary to the universalist account, we found language-specific interference in a duration reproduction task, where stimulus duration conflicted with its physical growth. When reproducing duration, Swedish speakers were misled by stimulus length, and Spanish speakers were misled by stimulus size/quantity. These patterns conform to preferred expressions of duration magnitude in these languages (Swedish: long/short time; Spanish: much/small time). Critically, Spanish-Swedish bilinguals performing the task in both languages showed different interference depending on language context. Such shifting behavior within the same individual reveals hitherto undocumented levels of flexibility in time representation. Finally, contrary to the linguistic relativity hypothesis, language interference was confined to difficult discriminations (i.e., when stimuli varied only subtly in duration and growth), and was eliminated when linguistic cues were removed from the task. These results reveal the malleable nature of human time representation as part of a highly adaptive information processing system. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Predicting the 'where' and resolving the 'what' of a moving target: a dichotomy of abilities.

PubMed

Long, G M; Vogel, C A

1998-01-01

Anticipation timing (AT) and dynamic visual acuity (DVA) were assessed in a group of college students (n = 60) under a range of velocity and duration conditions. Subjects participated in two identical sessions 1 week apart. Consistently with previous work, DVA performance worsened as velocity increased and as target duration decreased; and there was a significant improvement from the first to the second session. In contrast, AT performance improved as velocity increased, whereas no improvement from the first to the second session was indicated; but increasing duration again benefited performance. Correlational analyses comparing DVA and AT did not reveal any systematic relationship between the two visual tasks. A follow-up study with different instructions on the AT task revealed the same pattern of AT performance, suggesting the generalizability of the obtained stimulus relationships for the AT task. The importance of the often-overlooked role of stimulus variables on the AT task is discussed.

Exploring the Relationship between Students' Understanding of Conventional Time and Deep (Geologic) Time

NASA Astrophysics Data System (ADS)

Cheek, Kim A.

2013-07-01

Many geologic processes occur in the context of geologic or deep time. Students of all ages demonstrate difficulty grasping this fundamental concept which impacts their ability to acquire other geoscience concepts. A concept of deep time requires the ability to sequence events on an immense temporal scale (succession) and to judge the durations of geologic processes based on the rates at which they occur. The twin concepts of succession and duration are the same ideas that underlie a concept of conventional time. If deep time is an extension of conventional time and not qualitatively different from it, students should display similar reasoning patterns when dealing with analogous tasks over disparate temporal periods. Thirty-five US students aged 13-24 years participated in individual task-based interviews to ascertain how they thought about succession and duration in conventional and deep time. This is the first attempt to explore this relationship in the same study in over 30 years. Most students successfully completed temporal succession tasks, but there was greater variability in responses on duration tasks. Conventional time concepts appear to impact how students reason about deep time. The application of spatial reasoning to temporal tasks sometimes leads to correct responses but in other instances does not. Implications for future research and teaching strategies are discussed.

Robot initiative in a team learning task increases the rhythm of interaction but not the perceived engagement.

PubMed

Ivaldi, Serena; Anzalone, Salvatore M; Rousseau, Woody; Sigaud, Olivier; Chetouani, Mohamed

2014-01-01

We hypothesize that the initiative of a robot during a collaborative task with a human can influence the pace of interaction, the human response to attention cues, and the perceived engagement. We propose an object learning experiment where the human interacts in a natural way with the humanoid iCub. Through a two-phases scenario, the human teaches the robot about the properties of some objects. We compare the effect of the initiator of the task in the teaching phase (human or robot) on the rhythm of the interaction in the verification phase. We measure the reaction time of the human gaze when responding to attention utterances of the robot. Our experiments show that when the robot is the initiator of the learning task, the pace of interaction is higher and the reaction to attention cues faster. Subjective evaluations suggest that the initiating role of the robot, however, does not affect the perceived engagement. Moreover, subjective and third-person evaluations of the interaction task suggest that the attentive mechanism we implemented in the humanoid robot iCub is able to arouse engagement and make the robot's behavior readable.

Robot initiative in a team learning task increases the rhythm of interaction but not the perceived engagement

PubMed Central

Ivaldi, Serena; Anzalone, Salvatore M.; Rousseau, Woody; Sigaud, Olivier; Chetouani, Mohamed

2014-01-01

We hypothesize that the initiative of a robot during a collaborative task with a human can influence the pace of interaction, the human response to attention cues, and the perceived engagement. We propose an object learning experiment where the human interacts in a natural way with the humanoid iCub. Through a two-phases scenario, the human teaches the robot about the properties of some objects. We compare the effect of the initiator of the task in the teaching phase (human or robot) on the rhythm of the interaction in the verification phase. We measure the reaction time of the human gaze when responding to attention utterances of the robot. Our experiments show that when the robot is the initiator of the learning task, the pace of interaction is higher and the reaction to attention cues faster. Subjective evaluations suggest that the initiating role of the robot, however, does not affect the perceived engagement. Moreover, subjective and third-person evaluations of the interaction task suggest that the attentive mechanism we implemented in the humanoid robot iCub is able to arouse engagement and make the robot's behavior readable. PMID:24596554

Work motivation, task delegation and job satisfaction of general practice staff: a cross-sectional study.

PubMed

Riisgaard, Helle; Søndergaard, Jens; Munch, Maria; Le, Jette V; Ledderer, Loni; Pedersen, Line B; Nexøe, Jørgen

2017-04-01

Recent research has shown that a high degree of task delegation is associated with the practise staff's overall job satisfaction, and this association is important to explore since job satisfaction is related to medical as well as patient-perceived quality of care. This study aimed: (1) to investigate associations between degrees of task delegation in the management of chronic disease in general practice, with chronic obstructive pulmonary disease (COPD) as a case and the staff's work motivation, (2) to investigate associations between the work motivation of the staff and their job satisfaction. The study was based on a questionnaire to which 621 members of the practice staff responded. The questionnaire consisted of a part concerning degree of task delegation in the management of COPD in their respective practice and another part being about their job satisfaction and motivation to work. In the first analysis, we found that 'maximal degree' of task delegation was significantly associated with the staff perceiving themselves to have a large degree of variation in tasks, odds ratio (OR) = 4.26, confidence interval (CI) = 1.09, 16.62. In the second analysis, we found that this perceived large degree of variation in tasks was significantly associated with their overall job satisfaction, OR = 2.81, confidence interval = 1.71, 4.61. The results suggest that general practitioners could delegate highly complex tasks in the management of COPD to their staff without influencing the staff's work motivation, and thereby their job satisfaction, negatively, as long as they ensure sufficient variation in the tasks. © The Author 2017. Published by Oxford University Press.

Secondary task for full flight simulation incorporating tasks that commonly cause pilot error: Time estimation

NASA Technical Reports Server (NTRS)

Rosch, E.

1975-01-01

The task of time estimation, an activity occasionally performed by pilots during actual flight, was investigated with the objective of providing human factors investigators with an unobtrusive and minimally loading additional task that is sensitive to differences in flying conditions and flight instrumentation associated with the main task of piloting an aircraft simulator. Previous research indicated that the duration and consistency of time estimates is associated with the cognitive, perceptual, and motor loads imposed by concurrent simple tasks. The relationships between the length and variability of time estimates and concurrent task variables under a more complex situation involving simulated flight were clarified. The wrap-around effect with respect to baseline duration, a consequence of mode switching at intermediate levels of concurrent task distraction, should contribute substantially to estimate variability and have a complex effect on the shape of the resulting distribution of estimates.

Perceived vs. Actual Strategy Use across Three Oral Communication Tasks

ERIC Educational Resources Information Center

Khan, Sarah; Victori, Mia

2011-01-01

This study sought to explore differences in strategy use across three oral communication tasks. Twenty-two intermediate level university students carried out three tasks in pairs at three different time periods. After each task, which varied in terms of cognitive, interactional and learner factors (Robinson, "International Review of Applied…

Roles of Perceived Motivational Climates Created by Coach, Peer, and Parent on Dispositional Flow in Young Athletes.

PubMed

Çağlar, Emine; Aşçi, F Hülya; Uygurtaş, Murat

2017-04-01

We investigated the contribution of perceived motivational climates created by coach, peer, and parent on the dispositional flow experience of young athletes. Eighty-six female ( M age  = 14.24, SD = 1.38 years) and 134 male ( M age  = 16.28, SD = 1.17 years) athletes completed questionnaires of perceived motivational climates created by coach, peer, and parent and the Dispositional Flow Scale-2. Results of hierarchical multiple regression analyses indicated that perceived task-involving coach (β = .40, p < .001) and peer (β = .28, p < .002) motivational climates were the only significant predictors of dispositional flow. These findings suggest that task-involving motivational climates should be strengthened to increase experience of flow.

Does Flattened Sky Dome Reduces Perceived Moon Size

NASA Astrophysics Data System (ADS)

Toskovic, O.

2009-09-01

The aim of this study was to examine the Flattened sky dome model as an explanation of the Moon illusion. Two experiments were done, in a dark room, in which distribution of depth cues is the same towards horizon as towards zenith. In the first experiment 14 participants had the task to equalize the perceived distances of three stimuli in three directions (horizontal, tilted 45 degrees and vertical). In the second experiment 16 participants had the task to estimate the perceived sizes of three stimuli in the same three directions. For distance estimates we found differences among three directions in a way, that as the head tilts upwards, the perceived space is being elongated, which is the opposite to flattened sky dome. For size estimates we found no difference among the three directions.

The effects of social support and stress perception on bulimic behaviors and unhealthy food consumption.

PubMed

Kwan, Mun Yee; Gordon, Kathryn H

2016-08-01

Two studies tested a model where perceived stress was the proposed mediator for the relationship between perceived social support and bulimic behaviors, and between perceived social support and unhealthy food consumption among undergraduate students. Study 1 was a longitudinal, online study in which undergraduate students completed the Multidimensional Scale of Perceived Social Support and the Bulimia Test-Revised at the Time 1 assessment, and the Perceived Stress Scale and the Eating Disorder Examination Questionnaire at the Time 2 assessment, approximately four weeks later. Study 2 was an experimental study in which female participants were randomly assigned into a group with or without social support. Stress was induced with a speech task, followed by a bogus taste task paradigm designed to assess unhealthy food consumption. Bootstrap analyses revealed an indirect effect of perceived social support on bulimic behaviors and unhealthy food consumption through perceived stress. Perceived social support was associated with lower perceived stress in both studies. Lower perceived stress was associated with less self-reported bulimic behaviors in Study 1 and greater consumption of unhealthy foods in Study 2. The negative association between perceived stress and calorie consumption in Study 2 was moderated by dietary restraint. Findings suggest that stress perception helps to explain the relationship between perceived social support and bulimic behaviors, and between perceived social support and calorie consumption. Stress perception may be an important treatment target for eating disorder symptoms among undergraduate students. Copyright © 2016 Elsevier Ltd. All rights reserved.

Selecting Learning Tasks: Effects of Adaptation and Shared Control on Learning Efficiency and Task Involvement

ERIC Educational Resources Information Center

Corbalan, Gemma; Kester, Liesbeth; van Merrienboer, Jeroen J. G.

2008-01-01

Complex skill acquisition by performing authentic learning tasks is constrained by limited working memory capacity [Baddeley, A. D. (1992). Working memory. "Science, 255", 556-559]. To prevent cognitive overload, task difficulty and support of each newly selected learning task can be adapted to the learner's competence level and perceived task…

Task Complexity and Modality: Exploring Learners' Experience from the Perspective of Flow

ERIC Educational Resources Information Center

Cho, Minyoung

2018-01-01

Despite an increased awareness of language learner performance in task-based instruction, little is known about how learners perceive and respond to different task factors. This study investigates the effects of task complexity and modality on (a) learners' perception of task difficulty, skill, and its balance, and on (b) learners' task…

Comparison of School Counselors and School Social Workers: Performance of Tasks and Perceived Preparedness

ERIC Educational Resources Information Center

Feldman, Matthew

2010-01-01

This study compares the professional roles of school counselors and school social workers in terms of the frequency of performing various practice tasks, feelings of preparedness to perform various practice tasks, discrepancies between frequency of task performance and feelings of preparedness to perform said tasks, and factors that may affect…

Individual Differences in Working-Memory Capacity and Task Resumption Following Interruptions

ERIC Educational Resources Information Center

Foroughi, Cyrus K.; Werner, Nicole E.; McKendrick, Ryan; Cades, David M.; Boehm-Davis, Deborah A.

2016-01-01

Previous research has shown that there is a time cost (i.e., a resumption lag) associated with resuming a task following an interruption and that the longer the duration of the interruption, the greater the time cost (i.e., resumption lag increases as interruption duration increases). The memory-for-goals model (Altmann & Trafton, 2002)…

Duration of use of oral cannabis extract in a cohort of pediatric epilepsy patients.

PubMed

Treat, Lauren; Chapman, Kevin E; Colborn, Kathryn L; Knupp, Kelly G

2017-01-01

Oral cannabis extracts (OCEs) are being used in the treatment of epilepsy with increasing rates in the United States following product legalization; however, no studies demonstrate clear efficacy. We evaluated the duration of use of OCEs as a measure of perceived benefit in a cohort of patients with pediatric epilepsy. Retrospective chart review was performed of children and adolescents who were given OCEs for treatment of epilepsy. Of the 119 patients included in the analysis, 71% terminated use of their OCE product during the study period. The average length of use of OCE was 11.7 months (range 0.3-57 months). Perceived seizure benefit was the only factor associated with longer duration of treatment with OCE (p < 0.01). Relocation to Colorado was associated with perceived benefit of OCEs for seizures (65% vs. 38%, p = 0.01), but was not independently associated with longer OCE use. Factors associated with shorter use included adverse effects (p = 0.03) and a diagnosis of Dravet syndrome (p = 0.02). Twenty-four percent of patients were considered OCE responders, which was defined by a parent's report of a > 50% reduction in seizures while on this therapy. Adverse events (AEs) were reported in 19% of patients, with the most common side effects being somnolence and worsening of seizures. Parental report of OCE use in refractory pediatric epilepsy suggests that some families perceive benefit from this therapy; however, discontinuation of these products is common. Duration appears to be affected by logical factors, such as perceived benefit and side effect profile. Surprisingly, families of patients with Dravet syndrome terminated use of OCEs more quickly than patients with other epilepsy syndromes. Results from this study highlight the need for rigorous clinical studies to characterize the efficacy and safety of OCEs, which can inform discussions with patients and families. Wiley Periodicals, Inc. © 2016 International League Against Epilepsy.

Sources of unbounded priority inversions in real-time systems and a comparative study of possible solutions

NASA Technical Reports Server (NTRS)

Davari, Sadegh; Sha, Lui

1992-01-01

In the design of real-time systems, tasks are often assigned priorities. Preemptive priority driven schedulers are used to schedule tasks to meet the timing requirements. Priority inversion is the term used to describe the situation when a higher priority task's execution is delayed by lower priority tasks. Priority inversion can occur when there is contention for resources among tasks of different priorities. The duration of priority inversion could be long enough to cause tasks to miss their dead lines. Priority inversion cannot be completely eliminated. However, it is important to identify sources of priority inversion and minimize the duration of priority inversion. In this paper, a comprehensive review of the problem of and solutions to unbounded priority inversion is presented.

Hearing history influences voice gender perceptual performance in cochlear implant users.

PubMed

Kovačić, Damir; Balaban, Evan

2010-12-01

The study was carried out to assess the role that five hearing history variables (chronological age, age at onset of deafness, age of first cochlear implant [CI] activation, duration of CI use, and duration of known deafness) play in the ability of CI users to identify speaker gender. Forty-one juvenile CI users participated in two voice gender identification tasks. In a fixed, single-interval task, subjects listened to a single speech item from one of 20 adult male or 20 adult female speakers and had to identify speaker gender. In an adaptive speech-based voice gender discrimination task with the fundamental frequency difference between the voices as the adaptive parameter, subjects listened to a pair of speech items presented in sequential order, one of which was always spoken by an adult female and the other by an adult male. Subjects had to identify the speech item spoken by the female voice. Correlation and regression analyses between perceptual scores in the two tasks and the hearing history variables were performed. Subjects fell into three performance groups: (1) those who could distinguish voice gender in both tasks, (2) those who could distinguish voice gender in the adaptive but not the fixed task, and (3) those who could not distinguish voice gender in either task. Gender identification performance for single voices in the fixed task was significantly and negatively related to the duration of deafness before cochlear implantation (shorter deafness yielded better performance), whereas performance in the adaptive task was weakly but significantly related to age at first activation of the CI device, with earlier activations yielding better scores. The existence of a group of subjects able to perform adaptive discrimination but unable to identify the gender of singly presented voices demonstrates the potential dissociability of the skills required for these two tasks, suggesting that duration of deafness and age of cochlear implantation could have dissociable effects on the development of different skills required by CI users to identify speaker gender.

Incremental effects of reward on creativity.

PubMed

Eisenberger, R; Rhoades, L

2001-10-01

The authors examined 2 ways reward might increase creativity. First, reward contingent on creativity might increase extrinsic motivation. Studies 1 and 2 found that repeatedly giving preadolescent students reward for creative performance in 1 task increased their creativity in subsequent tasks. Study 3 reported that reward promised for creativity increased college students' creative task performance. Second, expected reward for high performance might increase creativity by enhancing perceived self-determination and, therefore, intrinsic task interest. Study 4 found that employees' intrinsic job interest mediated a positive relationship between expected reward for high performance and creative suggestions offered at work. Study 5 found that employees' perceived self-determination mediated a positive relationship between expected reward for high performance and the creativity of anonymous suggestions for helping the organization.

A randomised controlled trial of sensory awareness training and additional motor practice for learning scalpel skills in podiatry students.

PubMed

Causby, Ryan S; McDonnell, Michelle N; Reed, Lloyd; Hillier, Susan L

2016-12-05

The process of using a scalpel, like all other motor activities, is dependent upon the successful integration of afferent (sensory), cognitive and efferent (motor) processes. During learning of these skills, even if motor practice is carefully monitored there is still an inherent risk involved. It is also possible that this strategy could reinforce high levels of anxiety experienced by the student and affect student self-efficacy, causing detrimental effects on motor learning. An alternative training strategy could be through targeting sensory rather than motor processes. Second year podiatry students who were about to commence learning scalpel skills were recruited. Participants were randomly allocated into sensory awareness training (Sensory), additional motor practice (Motor) or usual teaching only (Control) groups. Participants were then evaluated on psychological measures (Intrinsic Motivation Inventory) and dexterity measures (Purdue Pegboard, Grooved Pegboard Test and a grip-lift task). A total of 44 participants were included in the study. There were no baseline differences or significant differences between the three groups over time on the Perceived Competence, Effort/ Importance or Pressure/ Tension, psychological measures. All groups showed a significant increase in Perceived Competence over time (F 1,41  = 13.796, p = 0.001). Only one variable for the grip-lift task (Preload Duration for the non-dominant hand) showed a significant difference over time between the groups (F 2,41  = 3.280, p = 0.038), specifically, Motor and Control groups. The use of sensory awareness training, or additional motor practice did not provide a more effective alternative compared with usual teaching. Further research may be warranted using more engaged training, provision of supervision and greater participant numbers. Australian New Zealand Clinical Trials Registry (ANZCTR): ACTRN12616001428459 . Registered 13 th October 2016. Registered Retrospectively.

Adolescents' Sleep Behaviors and Perceptions of Sleep

ERIC Educational Resources Information Center

Noland, Heather; Price, James H.; Dake, Joseph; Telljohann, Susan K.

2009-01-01

Background: Sleep duration affects the health of children and adolescents. Shorter sleep durations have been associated with poorer academic performance, unintentional injuries, and obesity in adolescents. This study extends our understanding of how adolescents perceive and deal with their sleep issues. Methods: General education classes were…

The effect of visual scanning exercises integrated into physiotherapy in patients with unilateral spatial neglect poststroke: a matched-pair randomized control trial.

PubMed

van Wyk, Andoret; Eksteen, Carina A; Rheeder, Paul

2014-01-01

Unilateral spatial neglect (USN) is a visual-perceptual disorder that entails the inability to perceive and integrate stimuli on one side of the body, resulting in the neglect of one side of the body. Stroke patients with USN present with extensive functional disability and duration of therapy input. To determine the effect of saccadic eye movement training with visual scanning exercises (VSEs) integrated with task-specific activities on USN poststroke. A matched-pair randomized control trial was conducted. Subjects were matched according to their functional activity level and allocated to either a control (n = 12) or an experimental group (n = 12). All patients received task-specific activities for a 4-week intervention period. The experimental group received saccadic eye movement training with VSE integrated with task specific activities as an "add on" intervention. Assessments were conducted weekly over the intervention period. Statistical significant difference was noted on the King-Devick Test (P = .021), Star Cancellation Test (P = .016), and Barthel Index (P = .004). Intensive saccadic eye movement training with VSE integrated with task-specific activities has a significant effect on USN in patients poststroke. Results of this study are supported by findings from previously reviewed literature in the sense that the effect of saccadic eye movement training with VSE as an intervention approach has a significant effect on the visual perceptual processing of participants with USN poststroke. The significant improved visual perceptual processing translate to significantly better visual function and ability to perform activities of daily living following the stroke. © The Author(s) 2014.

The cerebellum predicts the temporal consequences of observed motor acts.

PubMed

Avanzino, Laura; Bove, Marco; Pelosin, Elisa; Ogliastro, Carla; Lagravinese, Giovanna; Martino, Davide

2015-01-01

It is increasingly clear that we extract patterns of temporal regularity between events to optimize information processing. The ability to extract temporal patterns and regularity of events is referred as temporal expectation. Temporal expectation activates the same cerebral network usually engaged in action selection, comprising cerebellum. However, it is unclear whether the cerebellum is directly involved in temporal expectation, when timing information is processed to make predictions on the outcome of a motor act. Healthy volunteers received one session of either active (inhibitory, 1 Hz) or sham repetitive transcranial magnetic stimulation covering the right lateral cerebellum prior the execution of a temporal expectation task. Subjects were asked to predict the end of a visually perceived human body motion (right hand handwriting) and of an inanimate object motion (a moving circle reaching a target). Videos representing movements were shown in full; the actual tasks consisted of watching the same videos, but interrupted after a variable interval from its onset by a dark interval of variable duration. During the 'dark' interval, subjects were asked to indicate when the movement represented in the video reached its end by clicking on the spacebar of the keyboard. Performance on the timing task was analyzed measuring the absolute value of timing error, the coefficient of variability and the percentage of anticipation responses. The active group exhibited greater absolute timing error compared with the sham group only in the human body motion task. Our findings suggest that the cerebellum is engaged in cognitive and perceptual domains that are strictly connected to motor control.

Prospective and retrospective time perception are related to mental time travel: evidence from Alzheimer's disease.

PubMed

El Haj, Mohamad; Moroni, Christine; Samson, Séverine; Fasotti, Luciano; Allain, Philippe

2013-10-01

Unlike prospective time perception paradigms, in which participants are aware that they have to estimate forthcoming time, little is known about retrospective time perception in normal aging and Alzheimer's disease (AD). Our paper addresses this shortcoming by comparing prospective and retrospective time estimation in younger adults, older adults, and AD patients. In four prospective tasks (lasting 30s, 60s, 90s, or 120s) participants were asked to read a series of numbers and to provide a verbal estimation of the reading time. In four other retrospective tasks, they were not informed about time judgment until they were asked to provide a verbal estimation of four elapsed time intervals (lasting 30s, 60s, 90s, or 120s). AD participants gave shorter verbal time estimations than older adults and younger participants did, suggesting that time is perceived to pass quickly in these patients. For all participants, the duration of the retrospective tasks was underestimated as compared to the prospective tasks and both estimations were shorter than the real time interval. Prospective time estimation was further correlated with mental time travel, as measured with the Remember/Know paradigm. Mental time travel was even higher correlated with retrospective time estimation. Our findings shed light on the relationship between time perception and the ability to mentally project oneself into time, two skills contributing to human memory functioning. Finally, time perception deficits, as observed in AD patients, can be interpreted in terms of dramatic changes occurring in frontal lobes and hippocampus. Copyright © 2013 Elsevier Inc. All rights reserved.

A Role for Mouse Primary Visual Cortex in Motion Perception.

PubMed

Marques, Tiago; Summers, Mathew T; Fioreze, Gabriela; Fridman, Marina; Dias, Rodrigo F; Feller, Marla B; Petreanu, Leopoldo

2018-06-04

Visual motion is an ethologically important stimulus throughout the animal kingdom. In primates, motion perception relies on specific higher-order cortical regions. Although mouse primary visual cortex (V1) and higher-order visual areas show direction-selective (DS) responses, their role in motion perception remains unknown. Here, we tested whether V1 is involved in motion perception in mice. We developed a head-fixed discrimination task in which mice must report their perceived direction of motion from random dot kinematograms (RDKs). After training, mice made around 90% correct choices for stimuli with high coherence and performed significantly above chance for 16% coherent RDKs. Accuracy increased with both stimulus duration and visual field coverage of the stimulus, suggesting that mice in this task integrate motion information in time and space. Retinal recordings showed that thalamically projecting On-Off DS ganglion cells display DS responses when stimulated with RDKs. Two-photon calcium imaging revealed that neurons in layer (L) 2/3 of V1 display strong DS tuning in response to this stimulus. Thus, RDKs engage motion-sensitive retinal circuits as well as downstream visual cortical areas. Contralateral V1 activity played a key role in this motion direction discrimination task because its reversible inactivation with muscimol led to a significant reduction in performance. Neurometric-psychometric comparisons showed that an ideal observer could solve the task with the information encoded in DS L2/3 neurons. Motion discrimination of RDKs presents a powerful behavioral tool for dissecting the role of retino-forebrain circuits in motion processing. Copyright © 2018 Elsevier Ltd. All rights reserved.

Uncovering beat deafness: detecting rhythm disorders with synchronized finger tapping and perceptual timing tasks.

PubMed

Dalla Bella, Simone; Sowiński, Jakub

2015-03-16

A set of behavioral tasks for assessing perceptual and sensorimotor timing abilities in the general population (i.e., non-musicians) is presented here with the goal of uncovering rhythm disorders, such as beat deafness. Beat deafness is characterized by poor performance in perceiving durations in auditory rhythmic patterns or poor synchronization of movement with auditory rhythms (e.g., with musical beats). These tasks include the synchronization of finger tapping to the beat of simple and complex auditory stimuli and the detection of rhythmic irregularities (anisochrony detection task) embedded in the same stimuli. These tests, which are easy to administer, include an assessment of both perceptual and sensorimotor timing abilities under different conditions (e.g., beat rates and types of auditory material) and are based on the same auditory stimuli, ranging from a simple metronome to a complex musical excerpt. The analysis of synchronized tapping data is performed with circular statistics, which provide reliable measures of synchronization accuracy (e.g., the difference between the timing of the taps and the timing of the pacing stimuli) and consistency. Circular statistics on tapping data are particularly well-suited for detecting individual differences in the general population. Synchronized tapping and anisochrony detection are sensitive measures for identifying profiles of rhythm disorders and have been used with success to uncover cases of poor synchronization with spared perceptual timing. This systematic assessment of perceptual and sensorimotor timing can be extended to populations of patients with brain damage, neurodegenerative diseases (e.g., Parkinson's disease), and developmental disorders (e.g., Attention Deficit Hyperactivity Disorder).

Rats' Memory for Time and Relational Responding in the Duration-Comparison Procedure

ERIC Educational Resources Information Center

Santi, Angelo; Hoover, Claire; Simmons, Sabrina

2011-01-01

Rats were trained in a duration-comparison task to press one lever if the comparison duration ("c") was 1.2-s shorter than a standard duration ("s"), and another lever if c was 1.2-s longer than s. The interval between s and c duration was 1 s. The 10 duration pairs used during training controlled for the absolute duration of "c" and the total…

Social cognition and African American men: The roles of perceived discrimination and experimenter race on task performance.

PubMed

Nagendra, Arundati; Twery, Benjamin L; Neblett, Enrique W; Mustafic, Hasan; Jones, Tevin S; Gatewood, D'Angelo; Penn, David L

2018-01-01

The Social Cognition Psychometric Evaluation (SCOPE) study consists of a battery of eight tasks selected to measure social-cognitive deficits in individuals with schizophrenia. The battery is currently in a multisite validation process. While the SCOPE study collects basic demographic data, more nuanced race-related factors might artificially inflate cross-cultural differences in social cognition. As an initial step, we investigated whether race, independent of mental illness status, affects performance on the SCOPE battery. Thus, we examined the effects of perceived discrimination and experimenter race on the performance of 51 non-clinical African American men on the SCOPE battery. Results revealed that these factors impacted social cognitive task performance. Specifically, participants performed better on a skills-based task factor in the presence of Black experimenters, and frequency of perceived racism predicted increased perception of hostility in negative interpersonal situations with accidental causes. Thus, race-related factors are important to identify and explore in the measurement of social cognition in African Americans. Copyright © 2017 Elsevier B.V. All rights reserved.

Processing of Acoustic Cues in Lexical-Tone Identification by Pediatric Cochlear-Implant Recipients

PubMed Central

Peng, Shu-Chen; Lu, Hui-Ping; Lu, Nelson; Lin, Yung-Song; Deroche, Mickael L. D.

2017-01-01

Purpose The objective was to investigate acoustic cue processing in lexical-tone recognition by pediatric cochlear-implant (CI) recipients who are native Mandarin speakers. Method Lexical-tone recognition was assessed in pediatric CI recipients and listeners with normal hearing (NH) in 2 tasks. In Task 1, participants identified naturally uttered words that were contrastive in lexical tones. For Task 2, a disyllabic word (yanjing) was manipulated orthogonally, varying in fundamental-frequency (F0) contours and duration patterns. Participants identified each token with the second syllable jing pronounced with Tone 1 (a high level tone) as eyes or with Tone 4 (a high falling tone) as eyeglasses. Results CI participants' recognition accuracy was significantly lower than NH listeners' in Task 1. In Task 2, CI participants' reliance on F0 contours was significantly less than that of NH listeners; their reliance on duration patterns, however, was significantly higher than that of NH listeners. Both CI and NH listeners' performance in Task 1 was significantly correlated with their reliance on F0 contours in Task 2. Conclusion For pediatric CI recipients, lexical-tone recognition using naturally uttered words is primarily related to their reliance on F0 contours, although duration patterns may be used as an additional cue. PMID:28388709

Perceived displacement explains wolfpack effect

PubMed Central

Šimkovic, Matúš; Träuble, Birgit

2014-01-01

We investigate the influence of perceived displacement of moving agent-like stimuli on the performance in dynamic interactive tasks. In order to reliably measure perceived displacement we utilize multiple tasks with different task demands. The perceived center of an agent's body is displaced in the direction in which the agent is facing and this perceived displacement is larger than the theoretical position of the center of mass would predict. Furthermore, the displacement in the explicit judgment is dissociated from the displacement obtained by the implicit measures. By manipulating the location of the pivot point, we show that it is not necessary to postulate orientation as an additional cue utilized by perception, as has been suggested by earlier studies. These studies showed that the agent's orientation influences the detection of chasing motion and the detection-related performance in interactive tasks. This influence has been labeled wolfpack effect. In one of the demonstrations of the wolfpack effect participants control a green circle on a display with a computer mouse. It has been shown that participants avoid display areas with agents pointing toward the green circle. Participants do so in favor of areas where the agents point in the direction perpendicular to the circle. We show that this avoidance behavior arises because the agent's pivot point selected by the earlier studies is different from where people locate the center of agent's body. As a consequence, the nominal rotation confounds rotation and translation. We show that the avoidance behavior disappears once the pivot point is set to the center of agent's body. PMID:25566114

Effects of a weighted vest on attention to task and self-stimulatory behaviors in preschoolers with pervasive developmental disorders.

PubMed

Fertel-Daly, D; Bedell, G; Hinojosa, J

2001-01-01

This study examined the effectiveness of using a weighted vest for increasing attention to a fine motor task and decreasing self-stimulatory behaviors in preschool children with pervasive developmental disorders (PDD). Using an ABA single-subject design, the duration of attention to task and self-stimulatory behaviors and the number of distractions were measured in five preschool children with PDD over a period of 6 weeks. During the intervention phase, all participants displayed a decrease in the number of distractions and an increase in the duration of focused attention while wearing the weighted vest. All but 1 participant demonstrated a decrease in the duration of self-stimulatory behaviors while wearing a weighted vest; however, the type of self-stimulatory behaviors changed and became less self-abusive for this child while she wore the vest. During the intervention withdrawal phase, 3 participants experienced an increase in the duration of self-stimulatory behaviors, and all participants experienced an increase in the number of distractions and a decrease in the duration of focused attention. The increase or decrease, however, never returned to baseline levels for these behaviors. The findings suggest that for these 5 children with PDD, the use of a weighted vest resulted in an increase in attention to task and decrease in self-stimulatory behaviors. The most consistent improvement observed was the decreased number of distractions. Additional research is necessary to build consensus about the effectiveness of wearing a weighted vest to increase attention to task and decrease self-stimulatory behaviors for children with PDD.

Sequencing sit-to-stand and upright posture for mobility limitation assessment: determination of the timing of the task phases from force platform data.

PubMed

Mazzà, Claudia; Zok, Mounir; Della Croce, Ugo

2005-06-01

The identification of quantitative tools to assess an individual's mobility limitation is a complex and challenging task. Several motor tasks have been designated as potential indicators of mobility limitation. In this study, a multiple motor task obtained by sequencing sit-to-stand and upright posture was used. Algorithms based on data obtained exclusively from a single force platform were developed to detect the timing of the motor task phases (sit-to-stand, preparation to the upright posture and upright posture). To test these algorithms, an experimental protocol inducing predictable changes in the acquired signals was designed. Twenty-two young, able-bodied subjects performed the task in four different conditions: self-selected natural and high speed with feet kept together, and self-selected natural and high speed with feet pelvis-width apart. The proposed algorithms effectively detected the timing of the task phases, the duration of which was sensitive to the four different experimental conditions. As expected, the duration of the sit-to-stand was sensitive to the speed of the task and not to the foot position, while the duration of the preparation to the upright posture was sensitive to foot position but not to speed. In addition to providing a simple and effective description of the execution of the motor task, the correct timing of the studied multiple task could facilitate the accurate determination of variables descriptive of the single isolated phases, allowing for a more thorough description of the motor task and therefore could contribute to the development of effective quantitative functional evaluation tests.

Sleep duration, restfulness, and screens in the sleep environment.

PubMed

Falbe, Jennifer; Davison, Kirsten K; Franckle, Rebecca L; Ganter, Claudia; Gortmaker, Steven L; Smith, Lauren; Land, Thomas; Taveras, Elsie M

2015-02-01

Associations of inadequate sleep with numerous health outcomes among youth necessitate identifying its modifiable determinants. Television (TV) has been associated with sleep curtailment, but little is known about small screens (eg, smartphones), which can be used in bed and emit notifications. Therefore, we examined associations of different screens in sleep environments with sleep duration and perceived insufficient rest or sleep. Participants included 2048 fourth- and seventh-graders participating in the Massachusetts Childhood Obesity Research Demonstration Study in 2012 to 2013. Using linear and log binomial regression, we examined cross-sectional associations of small screens and TVs in sleep environments and screen time with weekday sleep duration and perceived insufficient rest or sleep in the past week. Children who slept near a small screen (compared with never) reported 20.6 fewer minutes of sleep (95% confidence interval [CI], -29.7 to -11.4) and had a higher prevalence of perceived insufficient rest or sleep (prevalence ratio, 1.39; 95% CI, 1.21 to 1.60). Children who slept in a room with a TV (compared with no TV) reported 18.0 fewer minutes of sleep (95% CI, -27.9 to -8.1). TV or DVD viewing and video or computer game playing were associated with both sleep outcomes (P < .01). Some associations were stronger among Hispanic, non-Hispanic black, and older children (P < .05 for heterogeneity). Sleeping near a small screen, sleeping with a TV in the room, and more screen time were associated with shorter sleep durations. Presence of a small screen, but not a TV, in the sleep environment and screen time were associated with perceived insufficient rest or sleep. These findings caution against unrestricted screen access in children's bedrooms. Copyright © 2015 by the American Academy of Pediatrics.

Addressing social influences reduces antibiotic duration in complicated abdominal infection: a mixed methods study.

PubMed

Broom, Jennifer; Tee, Chin Li; Broom, Alex; Kelly, Mark D; Scott, Tahira; Grieve, David A

2018-03-06

Antimicrobial therapy for intra-abdominal infections is often inappropriately prolonged. An intervention addressing factors influencing the duration of intravenous antibiotic use was undertaken. This study reports the antibiotic prescribing patterns before and after the intervention and a qualitative analysis of the experience of the intervention. Quantitative: A retrospective audit of patients with complicated intra-abdominal infection before and after a multifaceted persuasive intervention was performed. Qualitative: Semi-structured interviews were performed to evaluate which elements of the intervention were perceived to be effective. An intervention including collaborative inter-specialty and inter-professional educational meetings, and education of all professional streams was undertaken. Quantitative: Twenty-three patients before and 22 patients after the intervention were included. The total duration of antibiotics decreased significantly following the intervention (9.2 versus 6.6 days P = 0.02). The duration of intravenous antibiotics did not change significantly (5.4 versus 4.5 days, P = 0.06). Qualitative: Eighteen health-care professionals participated. Thematic analysis indicated that a collaborative approach between senior surgical and infectious disease specialists in the pre-intervention stage led to perceived ownership and leadership of the intervention by the surgical team, which was thought critical to the success of the intervention. Conversely, the ability of nurses and pharmacists to influence antibiotic practice was considered limited and a poster promoting the intervention was perceived as ineffective. Consultant leadership and specialty ownership of the process were perceived to be critical in the success of the intervention. Antibiotic stewardship programs which address social factors may have greater efficacy to optimize antimicrobial prescribing. © 2018 Royal Australasian College of Surgeons.

Sleep Duration, Restfulness, and Screens in the Sleep Environment

PubMed Central

Davison, Kirsten K.; Franckle, Rebecca L.; Ganter, Claudia; Gortmaker, Steven L.; Smith, Lauren; Land, Thomas; Taveras, Elsie M.

2015-01-01

BACKGROUND AND OBJECTIVE: Associations of inadequate sleep with numerous health outcomes among youth necessitate identifying its modifiable determinants. Television (TV) has been associated with sleep curtailment, but little is known about small screens (eg, smartphones), which can be used in bed and emit notifications. Therefore, we examined associations of different screens in sleep environments with sleep duration and perceived insufficient rest or sleep. METHODS: Participants included 2048 fourth- and seventh-graders participating in the Massachusetts Childhood Obesity Research Demonstration Study in 2012 to 2013. Using linear and log binomial regression, we examined cross-sectional associations of small screens and TVs in sleep environments and screen time with weekday sleep duration and perceived insufficient rest or sleep in the past week. RESULTS: Children who slept near a small screen (compared with never) reported 20.6 fewer minutes of sleep (95% confidence interval [CI], −29.7 to −11.4) and had a higher prevalence of perceived insufficient rest or sleep (prevalence ratio, 1.39; 95% CI, 1.21 to 1.60). Children who slept in a room with a TV (compared with no TV) reported 18.0 fewer minutes of sleep (95% CI, −27.9 to −8.1). TV or DVD viewing and video or computer game playing were associated with both sleep outcomes (P < .01). Some associations were stronger among Hispanic, non-Hispanic black, and older children (P < .05 for heterogeneity). CONCLUSIONS: Sleeping near a small screen, sleeping with a TV in the room, and more screen time were associated with shorter sleep durations. Presence of a small screen, but not a TV, in the sleep environment and screen time were associated with perceived insufficient rest or sleep. These findings caution against unrestricted screen access in children’s bedrooms. PMID:25560435

An Exploration of Rhythmic Grouping of Speech Sequences by French- and German-Learning Infants

PubMed Central

Abboub, Nawal; Boll-Avetisyan, Natalie; Bhatara, Anjali; Höhle, Barbara; Nazzi, Thierry

2016-01-01

Rhythm in music and speech can be characterized by a constellation of several acoustic cues. Individually, these cues have different effects on rhythmic perception: sequences of sounds alternating in duration are perceived as short-long pairs (weak-strong/iambic pattern), whereas sequences of sounds alternating in intensity or pitch are perceived as loud-soft, or high-low pairs (strong-weak/trochaic pattern). This perceptual bias—called the Iambic-Trochaic Law (ITL)–has been claimed to be an universal property of the auditory system applying in both the music and the language domains. Recent studies have shown that language experience can modulate the effects of the ITL on rhythmic perception of both speech and non-speech sequences in adults, and of non-speech sequences in 7.5-month-old infants. The goal of the present study was to explore whether language experience also modulates infants’ grouping of speech. To do so, we presented sequences of syllables to monolingual French- and German-learning 7.5-month-olds. Using the Headturn Preference Procedure (HPP), we examined whether they were able to perceive a rhythmic structure in sequences of syllables that alternated in duration, pitch, or intensity. Our findings show that both French- and German-learning infants perceived a rhythmic structure when it was cued by duration or pitch but not intensity. Our findings also show differences in how these infants use duration and pitch cues to group syllable sequences, suggesting that pitch cues were the easier ones to use. Moreover, performance did not differ across languages, failing to reveal early language effects on rhythmic perception. These results contribute to our understanding of the origin of rhythmic perception and perceptual mechanisms shared across music and speech, which may bootstrap language acquisition. PMID:27378887

Research on Mathematics Teachers as Partners in Task Design

ERIC Educational Resources Information Center

Jones, Keith; Pepin, Birgit

2016-01-01

Mathematical tasks and tools, including tasks in the form of digital tools, are key resources in mathematics teaching and in mathematics teacher education. Even so, the "design" of mathematical tasks is perceived in different ways: sometimes seen as something distinct from the teaching and learning process, and sometimes as integral to…

The Relationship between Levels of Expertise, Task Difficulty, Perceived Self-Efficacy, and Mental Effort Investment in Task Performance

ERIC Educational Resources Information Center

Ho, Hsin-Ning

2010-01-01

This study examined the impact of different levels of task difficulty and expertise on self-efficacy judgments. In addition, the study examines how self-efficacy judgments affect the amount of mental effort investment and task performance under different levels of task difficulty and expertise. Results from this study are used to build a…

Heart rate variability during acute psychosocial stress: A randomized cross-over trial of verbal and non-verbal laboratory stressors.

PubMed

Brugnera, Agostino; Zarbo, Cristina; Tarvainen, Mika P; Marchettini, Paolo; Adorni, Roberta; Compare, Angelo

2018-05-01

Acute psychosocial stress is typically investigated in laboratory settings using protocols with distinctive characteristics. For example, some tasks involve the action of speaking, which seems to alter Heart Rate Variability (HRV) through acute changes in respiration patterns. However, it is still unknown which task induces the strongest subjective and autonomic stress response. The present cross-over randomized trial sought to investigate the differences in perceived stress and in linear and non-linear analyses of HRV between three different verbal (Speech and Stroop) and non-verbal (Montreal Imaging Stress Task; MIST) stress tasks, in a sample of 60 healthy adults (51.7% females; mean age = 25.6 ± 3.83 years). Analyses were run controlling for respiration rates. Participants reported similar levels of perceived stress across the three tasks. However, MIST induced a stronger cardiovascular response than Speech and Stroop tasks, even after controlling for respiration rates. Finally, women reported higher levels of perceived stress and lower HRV both at rest and in response to acute psychosocial stressors, compared to men. Taken together, our results suggest the presence of gender-related differences during psychophysiological experiments on stress. They also suggest that verbal activity masked the vagal withdrawal through altered respiration patterns imposed by speaking. Therefore, our findings support the use of highly-standardized math task, such as MIST, as a valid and reliable alternative to verbal protocols during laboratory studies on stress. Copyright © 2018 Elsevier B.V. All rights reserved.

Changes of lumbar posture and tissue loading during static trunk bending.

PubMed

Alessa, Faisal; Ning, Xiaopeng

2018-02-01

Static trunk bending is an occupational risk factor for lower back pain (LBP). When assessing relative short duration trunk bending tasks, existing studies mostly assumed unchanged spine biomechanical responses during task performance. The purpose of the current study was to assess the biomechanical changes of lumbar spine during the performance of relatively short duration, sustained trunk bending tasks. Fifteen participants performed 40-s static trunk bending tasks in two different trunk angles (30° or 60°) with two different hand load levels (0 or 6.8 kg). Results of the current study revealed significantly increased lumbar flexion and lumbar passive moment during the 40 s of trunk bending. Significantly reduced lumbar and abdominal muscle activities were also observed in most conditions. These findings suggest that, during the performance of short duration, static trunk bending tasks, a shift of loading from lumbar active tissues to passive tissues occurs naturally. This mechanism is beneficial in reducing the accumulation of lumbar muscle fatigue; however, lumbar passive tissue creep could be introduced due to prolonged or repetitive exposure. Copyright © 2017 Elsevier B.V. All rights reserved.

Silence is golden: effect of encouragement in motivating the weak link in an online exercise video game.

PubMed

Irwin, Brandon C; Feltz, Deborah L; Kerr, Norbert L

2013-06-04

Despite the physical and mental health benefits, few adults meet US Department of Health and Human Services physical activity guidelines for exercise frequency, intensity, and duration. One strategy that may increase physical activity duration is exercising with an Internet partner (ie, someone who is virtually present, as in video chat). Internet partners help people overcome many barriers associated with face-to-face exercise groups (eg, time, coordinating schedules, social physique anxiety). Past research examining individual performance in groups suggests that an increase in effort occurs when performing a task conjunctively, ie, when a participant is (1) less capable than fellow group members, and (2) participants efforts are particularly indispensable for group success (ie, where the group's potential productivity is equal to the productivity of its least capable member). This boost in effort is more commonly known as the Köhler effect, named after the German psychologist who first observed the effect. While encouragement between group members is common practice in face-to-face group exercise, the effect of encouragement between partners exercising conjunctively across the Internet is unknown. To examine the impact of exercising alone, compared to exercising conjunctively with an Internet partner, both with and without encouragement, on exercise persistence (primary outcomes) and secondary psychosocial outcomes (self-efficacy, enjoyment, exercise intention). Participants were recruited online and face-to-face from the campus of Michigan State University. With the assistance of the experimenter, participants (n=115) played an exercise video game in a laboratory, performing a series of five abdominal plank exercises where they were asked to hold the plank for as long as possible (Time 1). They were then randomized to a condition (Individual, Partner-without-encouragement, or Partner-with-encouragement), where they performed the exercises again (Time 2). The impact of condition on the primary outcome measures and secondary outcome measures were evaluated using a 2 (Gender) x 3 (Condition) ANOVA on change scores (Time 2-Time 1). Those who exercised in online teams (n=80) exercised significantly longer (time=78.8s, P<.001) than those who worked individually (n=35). However, exercise duration was shorter when one's more capable partner gave verbal encouragement (n=55) than when s/he did not (n=25) (a mean difference of 31.14s). These increases in effort were not accompanied by altered task self-efficacy, enjoyment of the task, or intention to exercise in the future. Exercising conjunctively with an Internet partner can boost one's duration of exercise. However, encouragement from the stronger to the weaker member can mitigate these gains, especially if one perceives such comments being directed at someone other than themselves. To boost exercise duration, Internet-based physical activity interventions involving group interaction should make relative abilities of participants known and communication clear.

Relative versus Absolute Stimulus Control in the Temporal Bisection Task

ERIC Educational Resources Information Center

de Carvalho, Marilia Pinhiero; Machado, Armando

2012-01-01

When subjects learn to associate two sample durations with two comparison keys, do they learn to associate the keys with the short and long samples (relational hypothesis), or with the specific sample durations (absolute hypothesis)? We exposed 16 pigeons to an ABA design in which phases A and B corresponded to tasks using samples of 1 s and 4 s,…

Finding the beat: a neural perspective across humans and non-human primates.

PubMed

Merchant, Hugo; Grahn, Jessica; Trainor, Laurel; Rohrmeier, Martin; Fitch, W Tecumseh

2015-03-19

Humans possess an ability to perceive and synchronize movements to the beat in music ('beat perception and synchronization'), and recent neuroscientific data have offered new insights into this beat-finding capacity at multiple neural levels. Here, we review and compare behavioural and neural data on temporal and sequential processing during beat perception and entrainment tasks in macaques (including direct neural recording and local field potential (LFP)) and humans (including fMRI, EEG and MEG). These abilities rest upon a distributed set of circuits that include the motor cortico-basal-ganglia-thalamo-cortical (mCBGT) circuit, where the supplementary motor cortex (SMA) and the putamen are critical cortical and subcortical nodes, respectively. In addition, a cortical loop between motor and auditory areas, connected through delta and beta oscillatory activity, is deeply involved in these behaviours, with motor regions providing the predictive timing needed for the perception of, and entrainment to, musical rhythms. The neural discharge rate and the LFP oscillatory activity in the gamma- and beta-bands in the putamen and SMA of monkeys are tuned to the duration of intervals produced during a beat synchronization-continuation task (SCT). Hence, the tempo during beat synchronization is represented by different interval-tuned cells that are activated depending on the produced interval. In addition, cells in these areas are tuned to the serial-order elements of the SCT. Thus, the underpinnings of beat synchronization are intrinsically linked to the dynamics of cell populations tuned for duration and serial order throughout the mCBGT. We suggest that a cross-species comparison of behaviours and the neural circuits supporting them sets the stage for a new generation of neurally grounded computational models for beat perception and synchronization. © 2015 The Author(s) Published by the Royal Society. All rights reserved.

Finding the beat: a neural perspective across humans and non-human primates

PubMed Central

Merchant, Hugo; Grahn, Jessica; Trainor, Laurel; Rohrmeier, Martin; Fitch, W. Tecumseh

2015-01-01

Humans possess an ability to perceive and synchronize movements to the beat in music (‘beat perception and synchronization’), and recent neuroscientific data have offered new insights into this beat-finding capacity at multiple neural levels. Here, we review and compare behavioural and neural data on temporal and sequential processing during beat perception and entrainment tasks in macaques (including direct neural recording and local field potential (LFP)) and humans (including fMRI, EEG and MEG). These abilities rest upon a distributed set of circuits that include the motor cortico-basal-ganglia–thalamo-cortical (mCBGT) circuit, where the supplementary motor cortex (SMA) and the putamen are critical cortical and subcortical nodes, respectively. In addition, a cortical loop between motor and auditory areas, connected through delta and beta oscillatory activity, is deeply involved in these behaviours, with motor regions providing the predictive timing needed for the perception of, and entrainment to, musical rhythms. The neural discharge rate and the LFP oscillatory activity in the gamma- and beta-bands in the putamen and SMA of monkeys are tuned to the duration of intervals produced during a beat synchronization–continuation task (SCT). Hence, the tempo during beat synchronization is represented by different interval-tuned cells that are activated depending on the produced interval. In addition, cells in these areas are tuned to the serial-order elements of the SCT. Thus, the underpinnings of beat synchronization are intrinsically linked to the dynamics of cell populations tuned for duration and serial order throughout the mCBGT. We suggest that a cross-species comparison of behaviours and the neural circuits supporting them sets the stage for a new generation of neurally grounded computational models for beat perception and synchronization. PMID:25646516

Listening Natively across Perceptual Domains?

ERIC Educational Resources Information Center

Langus, Alan; Seyed-Allaei, Shima; Uysal, Ertugrul; Pirmoradian, Sahar; Marino, Caterina; Asaadi, Sina; Eren, Ömer; Toro, Juan M.; Peña, Marcela; Bion, Ricardo A. H.; Nespor, Marina

2016-01-01

Our native tongue influences the way we perceive other languages. But does it also determine the way we perceive nonlinguistic sounds? The authors investigated how speakers of Italian, Turkish, and Persian group sequences of syllables, tones, or visual shapes alternating in either frequency or duration. We found strong native listening effects…

Perceptual aspects of singing.

PubMed

Sundberg, J

1994-06-01

The relations between acoustic and perceived characteristics of vowel sounds are demonstrated with respect to timbre, loudness, pitch, and expressive time patterns. The conditions for perceiving an ensemble of sine tones as one tone or several tones are reviewed. There are two aspects of timbre of voice sounds: vowel quality and voice quality. Although vowel quality depends mainly on the frequencies of the lowest two formants. In particular, the center frequency of the so-called singer's formant seems perceptually relevant. Vocal loudness, generally assumed to correspond closely to the sound pressure level, depends rather on the amplitude balance between the lower and the higher spectrum partials. The perceived pitch corresponds to the fundamental frequency, or for vibrato tones, the mean of this frequency. In rapid passages, such as coloratura singing, special patterns are used. Pitch and duration differences are categorically perceived in music. This means that small variations in tuning or duration do not affect the musical interval and the note value perceived. Categorical perception is used extensively in music performance for the purpose of musical expression because without violating the score, the singer may sharpen or flatten and lengthen or shorten the tones, thereby creating musical expression.

Car seat safety: Typologies of protective health and safety behaviors for mothers in West Virginia

PubMed Central

Thornton, J. Douglas; Deb, Arijita; Murray, Pamela J.; Kelly, Kimberly M.

2016-01-01

Objective Parenting practices differ for a variety of reasons, and three parenting behaviors may be directly influenced by research, policy, and overall parenting trends: car safety seats, vaccination, and breastfeeding. Mothers were categorized in terms of their rear-facing car safety seat utilization and its relationship to other parental health and safety behaviors. Methods A cross-sectional, online survey of mothers of children under 3 years of age (n=124) was conducted. Items assessed mother’s perceived risk and worry about being in an automobile accident, as well as duration of rear-facing car seat utilization. A cluster analysis based on these variables was performed to differentiate the sample into four distinct groups. Outcomes were knowledge of car safety seats, breastfeeding duration, and adherence to vaccination schedules. Results The sample was predominantly White, had an average age of 32 years, had breastfed, and had at least some college education. Two groups of interest had (Group 1) long duration of rear-facing use with low perceived risk and worry and (Group 2) short use with high perceived risk and worry. Fisher’s Exact test indicated Group 1 had higher knowledge of airbag use with car seats (p=0.035), lower intentions to use the recommended vaccinations schedule (p=0.005), and were more likely to breastfeed (p=0.044) for longer duration (p=0.012). Conclusion Propensity for mothers’ risk aversion may be the crucial element in both an appropriate duration of rear-facing car safety seat use and refusal of recommended vaccination schedule. PMID:27435731

Car Seat Safety: Typologies of Protective Health and Safety Behaviors for Mothers in West Virginia.

PubMed

Thornton, J Douglas; Deb, Arijita; Murray, Pamela J; Kelly, Kimberly M

2017-02-01

Objective Parenting practices differ for a variety of reasons, and three parenting behaviors may be directly influenced by research, policy, and overall parenting trends: car safety seats, vaccination, and breastfeeding. Mothers were categorized in terms of their rear-facing car safety seat utilization and its relationship to other parental health and safety behaviors. Methods A cross-sectional, online survey of mothers of children under 3 years of age (n = 124) was conducted. Items assessed mother's perceived risk and worry about being in an automobile accident, as well as duration of rear-facing car seat utilization. A cluster analysis based on these variables was performed to differentiate the sample into four distinct groups. Outcomes were knowledge of car safety seats, breastfeeding duration, and adherence to vaccination schedules. Results The sample was predominantly White, had an average age of 32 years, had breastfed, and had at least some college education. Two groups of interest had (Group 1) long duration of rear-facing use with low perceived risk and worry and (Group 2) short use with high perceived risk and worry. Fisher's Exact test indicated Group 1 had higher knowledge of airbag use with car seats (p = 0.035), lower intentions to use the recommended vaccinations schedule (p = 0.005), and were more likely to breastfeed (p = 0.044) for longer duration (p = 0.012). Conclusion Propensity for mothers' risk aversion may be the crucial element in both an appropriate duration of rear-facing car safety seat use and refusal of recommended vaccination schedule.

Perceived stigma and associated factors among people with epilepsy at Gondar University Hospital, Northwest Ethiopia: a cross-sectional institution based study.

PubMed

Bifftu, Berhanu Boru; Dachew, Berihun Assefa; Tiruneh, Bewket Tadesse

2015-12-01

Epilepsy is the world's most common neurological disorder, affecting approximately 69 million people worldwide. Perceived stigma affects many domains of the lives of people with epilepsy. However, in Ethiopia there is dearth of study on perceived stigma specifically among people with epilepsy. To assess the prevalence of perceived stigma and associated factors among people with epilepsy (PWE) attending the outpatient department of the University of Gondar hospital, Northwest Ethiopia, 2014. Institution based quantitative cross - sectional study was employed among 408 individuals people with epilepsy. Single population proportion formula was used utilized to calculate sample size. The participants were selected using systematic random sampling technique. Perceived stigma was measured using by the modified Family Interview Schedule (FIS) tool. Binary logistic regression analysis and adjusted odds ratio with 95% confidence interval were used to identify the associated factors with perceived stigma.. Overall, the prevalence of perceived stigma was found to be 71.6%. Marital status [single (AOR = 0.23, CI: 0.25, 0.90), widowed ( AOR = 0.37, CI: 0.15, 0.90) duration of illness [2-5 years (AOR = 4.38, CI:1.98,9.62, 6-10 years (AOR =4.29, CI:1.90,9.64, ≥11 years (AOR = 4.31,CI:1.84,10.00) and seizure frequency of [1-11per year (AOR=2.34, CI:2.21,3.56), ≥1per month (AOR = 5.63, CI:3.42,10.32)] were factors associated with perceived stigma. Overall, the prevalence of perceived stigma was found to be high. Marital status, long duration of illness and seizure frequency were factors associated with perceived stigma.

Loneliness in late-life depression: structural and functional connectivity during affective processing.

PubMed

Wong, N M L; Liu, H-L; Lin, C; Huang, C-M; Wai, Y-Y; Lee, S-H; Lee, T M C

2016-09-01

Late-life depression (LLD) in the elderly was reported to present with emotion dysregulation accompanied by high perceived loneliness. Previous research has suggested that LLD is a disorder of connectivity and is associated with aberrant network properties. On the other hand, perceived loneliness is found to adversely affect the brain, but little is known about its neurobiological basis in LLD. The current study investigated the relationships between the structural connectivity, functional connectivity during affective processing, and perceived loneliness in LLD. The current study included 54 participants aged >60 years of whom 31 were diagnosed with LLD. Diffusion tensor imaging (DTI) data and task-based functional magnetic resonance imaging (fMRI) data of an affective processing task were collected. Network-based statistics and graph theory techniques were applied, and the participants' perceived loneliness and depression level were measured. The affective processing task included viewing affective stimuli. Structurally, a loneliness-related sub-network was identified across all subjects. Functionally, perceived loneliness was related to connectivity differently in LLD than that in controls when they were processing negative stimuli, with aberrant networking in subcortical area. Perceived loneliness was identified to have a unique role in relation to the negative affective processing in LLD at the functional brain connectional and network levels. The findings increas our understanding of LLD and provide initial evidence of the neurobiological mechanisms of loneliness in LLD. Loneliness might be a potential intervention target in depressive patients.

Investigating the Association of Eye Gaze Pattern and Diagnostic Error in Mammography

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

Voisin, Sophie; Pinto, Frank M; Xu, Songhua

2013-01-01

The objective of this study was to investigate the association between eye-gaze patterns and the diagnostic accuracy of radiologists for the task of assessing the likelihood of malignancy of mammographic masses. Six radiologists (2 expert breast imagers and 4 Radiology residents of variable training) assessed the likelihood of malignancy of 40 biopsy-proven mammographic masses (20 malignant and 20 benign) on a computer monitor. Eye-gaze data were collected using a commercial remote eye-tracker. Upon reviewing each mass, the radiologists were also asked to provide their assessment regarding the probability of malignancy of the depicted mass as well as a rating regardingmore » the perceived difficulty of the diagnostic task. The collected data were analyzed using established algorithms and various quantitative metrics were extracted to characterize the recorded gaze patterns. The extracted metrics were correlated with the radiologists diagnostic decisions and perceived complexity scores. Results showed that the visual gaze pattern of radiologists varies substantially, not only depending on their experience level but also among individuals. However, some eye gaze metrics appear to correlate with diagnostic error and perceived complexity more consistently. These results suggest that although gaze patterns are generally associated with diagnostic error and the human perceived difficulty of the diagnostic task, there are substantially individual differences that are not explained simply by the experience level of the individual performing the diagnostic task.« less

The perceived effects and comfort of various body armour systems on police officers while performing occupational tasks.

PubMed

Schram, B; Hinton, B; Orr, R; Pope, R; Norris, G

2018-01-01

The nature of police work often necessitates use of Individual Light Armour Vests (ILAVs) for officer protection. Previous research has demonstrated various biomechanical and physical performance impacts of ILAVs, however, little knowledge exists on the individual officer's perceptions of ILAV. The aim of this study was to investigate officers' perceptions of the impacts of three different ILAVs and normal station wear whilst performing police occupational tasks. A prospective, within subjects, repeated measures design was employed in which 11 serving police officers wore each of three different types of body armour (ILAV A, ILAV B or ILAV C) and normal station wear for a full day while performing tasks including a simulated victim drag, a patrol vehicle exit and a marksmanship shoot. Ratings of Perceived Exertion (RPE) and a Visual Analogue Scale (VAS; - 10 to + 10) were used to examine officer perceptions of each ILAV. Finally, officers were asked to indicate areas of both discomfort and comfort of each ILAV on a mannequin chart. Officers perceived less effort was required for the victim drag whilst wearing ILAV B (RPE = 3.6/10) when compared to ILAV A, ILAV C and even station wear (RPE = 4.7/10, 4.0/10, 3.8/10, respectively). A positive impact on performance was perceived for ILAV B (VAS = + 0.26) when performing a patrol vehicle exit and sprint task but not for the other two ILAVs (VAS = - 3.58, - 0.55, - 0.85, respectively). Officers perceived a positive impact of ILAV B (VAS = + 2.7) and station wear (VAS = + 1.4) and a negative impact of ILAVs A and C (VAS = - 2.1, - 1.7 respectively) on marksmanship. Despite all armour types being criticized for discomfort, ILAV B received lower ratings of discomfort overall, and some positive comments regarding both comfort and performance. Officers perceived ILAV B to have positive effects on task performance. It was also rated more comfortable than the other two, possibly due to a longer torso design which shifted load from the shoulders to the hips and pelvis. Officer perceptions of comfort and effects on occupational performance should be considered when designing and procuring armour systems. Although ILAVs may be similar, perceived impacts may vary between officers.

Investigating the Effects of Prompts on Argumentation Style, Consensus and Perceived Efficacy in Collaborative Learning

ERIC Educational Resources Information Center

Harney, Owen M.; Hogan, Michael J.; Broome, Benjamin; Hall, Tony; Ryan, Cormac

2015-01-01

This paper investigates the effects of task-level versus process-level prompts on levels of perceived and objective consensus, perceived efficacy, and argumentation style in the context of a computer-supported collaborative learning session using Interactive Management (IM), a computer facilitated thought and action mapping methodology. Four…

Measuring information processing in a client with extreme agitation following traumatic brain injury using the Perceive, Recall, Plan and Perform System of Task Analysis.

PubMed

Nott, Melissa T; Chapparo, Christine

2008-09-01

Agitation following traumatic brain injury is characterised by a heightened state of activity with disorganised information processing that interferes with learning and achieving functional goals. This study aimed to identify information processing problems during task performance of a severely agitated adult using the Perceive, Recall, Plan and Perform (PRPP) System of Task Analysis. Second, this study aimed to examine the sensitivity of the PRPP System to changes in task performance over a short period of rehabilitation, and third, to evaluate the guidance provided by the PRPP in directing intervention. A case study research design was employed. The PRPP System of Task Analysis was used to assess changes in task embedded information processing capacity during occupational therapy intervention with a severely agitated adult in a rehabilitation context. Performance is assessed on three selected tasks over a one-month period. Information processing difficulties during task performance can be clearly identified when observing a severely agitated adult following a traumatic brain injury. Processing skills involving attention, sensory processing and planning were most affected at this stage of rehabilitation. These processing difficulties are linked to established descriptions of agitated behaviour. Fluctuations in performance across three tasks of differing processing complexity were evident, leading to hypothesised relationships between task complexity, environment and novelty with information processing errors. Changes in specific information processing capacity over time were evident based on repeated measures using the PRPP System of Task Analysis. This lends preliminary support for its utility as an outcome measure, and raises hypotheses about the type of therapy required to enhance information processing in people with severe agitation. The PRPP System is sensitive to information processing changes in severely agitated adults when used to reassess performance over short intervals and can provide direct guidance to occupational therapy intervention to improve task embedded information processing by categorising errors under four stages of an information processing model: Perceive, Recall, Plan and Perform.

Why do temporal generalization gradients change when people make decisions as quickly as possible?

PubMed

Klapproth, Florian; Wearden, John H

2011-08-01

Three experiments investigated temporal generalization performance under conditions in which participants were instructed to make their decisions as quickly as possible (speed), or were allowed to take their time (accuracy). A previous study (Klapproth & Müller, 2008) had shown that under speeded conditions people were more likely to confuse durations shorter than the standard with the standard than in the accuracy conditions, and a possible explanation of this result is that longer stimulus durations are "truncated" (i.e., people make a judgement about them before they have terminated, thereby shortening their effective duration) and that these truncated durations affect the standard used for the task. Experiment 1 investigated performance under speed and accuracy conditions when comparison durations were close to the standard or further away. No performance difference was found as a function of stimulus spacing, even though responses occurred on average before the longest durations had terminated, but this lack of effect was attributed to "task difficulty" effects changing decision thresholds. In Experiment 2, the standard duration was either the longest or the shortest duration in the comparison set, and differences between speed and accuracy groups occurred only when the comparisons were longer than the standard, supporting the "truncation" hypothesis. A third experiment showed that differences between speed and accuracy groups only occurred if some memory of the standard that was valid for more than one trial was used. In general, the results suggest that the generalization gradient shifts in speeded conditions occur because of truncation of longer comparison durations, which influences the effective standard used for the task.

Monkeys time their pauses of movement and not their movement-kinematics during a synchronization-continuation rhythmic task.

PubMed

Donnet, Sophie; Bartolo, Ramon; Fernandes, José Maria; Cunha, João Paulo Silva; Prado, Luis; Merchant, Hugo

2014-05-01

A critical question in tapping behavior is to understand whether the temporal control is exerted on the duration and trajectory of the downward-upward hand movement or on the pause between hand movements. In the present study, we determined the duration of both the movement execution and pauses of monkeys performing a synchronization-continuation task (SCT), using the speed profile of their tapping behavior. We found a linear increase in the variance of pause-duration as a function of interval, while the variance of the motor implementation was relatively constant across intervals. In fact, 96% of the variability of the duration of a complete tapping cycle (pause + movement) was due to the variability of the pause duration. In addition, we performed a Bayesian model selection to determine the effect of interval duration (450-1,000 ms), serial-order (1-6 produced intervals), task phase (sensory cued or internally driven), and marker modality (auditory or visual) on the duration of the movement-pause and tapping movement. The results showed that the most important parameter used to successfully perform the SCT was the control of the pause duration. We also found that the kinematics of the tapping movements was concordant with a stereotyped ballistic control of the hand pressing the push-button. The present findings support the idea that monkeys used an explicit timing strategy to perform the SCT, where a dedicated timing mechanism controlled the duration of the pauses of movement, while also triggered the execution of fixed movements across each interval of the rhythmic sequence. Copyright © 2014 the American Physiological Society.

Sleep duration and RSA suppression as predictors of internalizing and externalizing behaviors.

PubMed

Cho, Sunghye; Philbrook, Lauren E; Davis, Elizabeth L; Buss, Kristin A

2017-01-01

Although the conceptual interplay among the biological and clinical features of sleep, arousal, and emotion regulation has been noted, little is understood about how indices of sleep duration and parasympathetic reactivity operate jointly to predict adjustment in early childhood. Using a sample of 123 toddlers, the present study examined sleep duration and RSA reactivity as predictors of internalizing and externalizing behaviors. Parents reported on children's sleep duration and adjustment. RSA reactivity was assessed via children's responses to fear-eliciting stimuli and an inhibitory control challenge. Findings demonstrated that greater RSA suppression to both types of tasks in combination with longer sleep duration was concurrently associated with less internalizing. In contrast, greater RSA augmentation to an inhibitory control task in the context of shorter sleep duration predicted more externalizing 1 year later. The significance of duration of toddlers' sleep as well as the context in which physiological regulatory difficulties occurs is discussed. © 2016 Wiley Periodicals, Inc.

Acute Effects of MPH on the Parent-Teen Interactions of Adolescents With ADHD.

PubMed

Pelham, William E; Meichenbaum, David L; Smith, Bradley H; Sibley, Margaret H; Gnagy, Elizabeth M; Bukstein, Oscar

2017-01-01

This study explored the nature of interactions between adolescent males with ADHD and their mothers, and the effects of methylphenidate (MPH) on an analogue parent-teen interaction task. Twenty-five adolescent males with ADHD ( M = 13.6 years) and their mothers and 14 non-ADHD adolescent males ( M = 13.4 years) and their mothers completed ratings of perceived dyadic conflict. Behavioral observations of dyads during 10-min conflict-resolution tasks were also collected. The ADHD dyads completed these tasks twice, with adolescents receiving either 0.3 mg/kg MPH or placebo. Videotaped sessions were coded using the Parent-Adolescent Interaction Rating Scale. Following the conflict-resolution task, participants rated their perceived conflict and affect during the interaction. Findings indicated higher conflict in the ADHD dyads, and minimal MPH effects on parent-teen interactions during the analogue task. Results suggest that stimulant medication does not produce meaningful acute effects on parent-teen interactions.

Competence, achievement goals, motivational climate, and pleasant psychobiosocial states in youth sport.

PubMed

Bortoli, Laura; Bertollo, Maurizio; Comani, Silvia; Robazza, Claudio

2011-01-01

We examined the three-way interactions among competence (actual and perceived), individuals' dispositional goal orientation (task/ego), and perceived sport motivational climate (mastery/performance) in the prediction of pleasant psychobiosocial states (i.e. emotion, cognition, motivation, bodily reaction, movement, performance, and communication) as conceptualized by the Individual Zones of Optimal Functioning model. The sample consisted of 320 Italian youths (160 girls and 160 boys) aged 13-14 years who were involved in individual or team sports. The assessment included a perceived competence scale, a goal orientation questionnaire, a motivational climate inventory, and pleasant psychobiosocial descriptors. An actual competence scale was also administered to coaches asking them to assess their youngsters. Moderated hierarchical regression analysis showed that perceived competence, actual competence, and task orientation were the strongest predictors of pleasant psychobiosocial states. Moreover, actual competence and perceived competence interacted in different ways with dispositional goal orientations and motivational climate perceptions in the prediction of psychobiosocial states. It is therefore recommended that both constructs be included in motivational research.

Attention-dependent sound offset-related brain potentials.

PubMed

Horváth, János

2016-05-01

When performing sensory tasks, knowing the potentially occurring goal-relevant and irrelevant stimulus events allows the establishment of selective attention sets, which result in enhanced sensory processing of goal-relevant events. In the auditory modality, such enhancements are reflected in the increased amplitude of the N1 ERP elicited by the onsets of task-relevant sounds. It has been recently suggested that ERPs to task-relevant sound offsets are similarly enhanced in a tone-focused state in comparison to a distracted one. The goal of the present study was to explore the influence of attention on ERPs elicited by sound offsets. ERPs elicited by tones in a duration-discrimination task were compared to ERPs elicited by the same tones in not-tone-focused attentional setting. Tone offsets elicited a consistent, attention-dependent biphasic (positive-negative--P1-N1) ERP waveform for tone durations ranging from 150 to 450 ms. The evidence, however, did not support the notion that the offset-related ERPs reflected an offset-specific attention set: The offset-related ERPs elicited in a duration-discrimination condition (in which offsets were task relevant) did not significantly differ from those elicited in a pitch-discrimination condition (in which the offsets were task irrelevant). Although an N2 reflecting the processing of offsets in task-related terms contributed to the observed waveform, this contribution was separable from the offset-related P1 and N1. The results demonstrate that when tones are attended, offset-related ERPs may substantially overlap endogenous ERP activity in the postoffset interval irrespective of tone duration, and attention differences may cause ERP differences in such postoffset intervals. © 2016 Society for Psychophysiological Research.

The Effect of Global and Local Damping on the Perception of Hardness.

PubMed

van Beek, Femke Elise; Heck, Dennis J F; Nijmeijer, Henk; Bergmann Tiest, Wouter M; Kappers, Astrid M L

2016-01-01

In tele-operation systems, damping is often injected to guarantee system stability during contact with hard objects. In this study, we used psychophysical experiments to assess the effect of adding damping on the user's perception of object hardness. In Experiments 1 and 2, combinations of stiffness and damping were tested to assess their effect on perceived hardness. In both experiments, two tasks were used: an in-contact task, starting at the object's surface, and a contact-transition task, including a free-air movement. In Experiment 3, the difference between inserting damping globally (equally throughout the workspace) and locally (inside the object only) was tested. In all experiments, the correlation between the participant's perceptual decision and force and position data was also investigated. Experiments 1 and 2 show that when injecting damping globally, perceived hardness slightly increased for an in-contact task, while it decreased considerably for a contact-transition task. Experiment 3 shows that this effect was mainly due to inserting damping globally, since there was a large perceptual difference between inserting damping globally and locally. The force and position parameters suggest that participants used the same force profile during the two movements of one trial and assessed the system's reaction to this force to perceive hardness.

Noise disturbance in open-plan study environments: a field study on noise sources, student tasks and room acoustic parameters.

PubMed

Braat-Eggen, P Ella; van Heijst, Anne; Hornikx, Maarten; Kohlrausch, Armin

2017-09-01

The aim of this study is to gain more insight in the assessment of noise in open-plan study environments and to reveal correlations between noise disturbance experienced by students and the noise sources they perceive, the tasks they perform and the acoustic parameters of the open-plan study environment they work in. Data were collected in five open-plan study environments at universities in the Netherlands. A questionnaire was used to investigate student tasks, perceived sound sources and their perceived disturbance, and sound measurements were performed to determine the room acoustic parameters. This study shows that 38% of the surveyed students are disturbed by background noise in an open-plan study environment. Students are mostly disturbed by speech when performing complex cognitive tasks like studying for an exam, reading and writing. Significant but weak correlations were found between the room acoustic parameters and noise disturbance of students. Practitioner Summary: A field study was conducted to gain more insight in the assessment of noise in open-plan study environments at universities in the Netherlands. More than one third of the students was disturbed by noise. An interaction effect was found for task type, source type and room acoustic parameters.

Social ranking effects on tooth-brushing behaviour.

PubMed

Maltby, John; Paterson, Kevin; Day, Liz; Jones, Ceri; Kinnear, Hayley; Buchanan, Heather

2016-05-01

A tooth-brushing social rank hypothesis is tested suggesting tooth-brushing duration is influenced when individuals position their behaviour in a rank when comparing their behaviour with other individuals. Study 1 used a correlation design, Study 2 used a semi-experimental design, and Study 3 used a randomized intervention design to examine the tooth-brushing social rank hypothesis in terms of self-reported attitudes, cognitions, and behaviour towards tooth-brushing duration. Study 1 surveyed participants to examine whether the perceived health benefits of tooth-brushing duration could be predicted from the ranking of each person's tooth-brushing duration. Study 2 tested whether manipulating the rank position of the tooth-brushing duration influenced participant-perceived health benefits of tooth-brushing duration. Study 3 used a longitudinal intervention method to examine whether messages relating to the rank positions of tooth-brushing durations causally influenced the self-report tooth-brushing duration. Study 1 demonstrates that perceptions of the health benefits from tooth-brushing duration are predicted by the perceptions of how that behaviour ranks in comparison to other people's behaviour. Study 2 demonstrates that the perceptions of the health benefits of tooth-brushing duration can be manipulated experimentally by changing the ranked position of a person's tooth-brushing duration. Study 3 experimentally demonstrates the possibility of increasing the length of time for which individuals clean their teeth by focusing on how they rank among their peers in terms of tooth-brushing duration. The effectiveness of interventions using social-ranking methods relative to those that emphasize comparisons made against group averages or normative guidelines are discussed. What is already known on this subject? Individual make judgements based on social rank information. Social rank information has been shown to influence positive health behaviours such as exercise. What does this study add? The health benefits of tooth-brushing are predicted by how tooth-brushing duration ranks within a distribution. Focussing on how teeth-cleaning duration ranks among others produces longer teeth-cleaning durations. © 2015 The British Psychological Society.

Stressed and Losing Sleep: Sleep Duration and Perceived Stress among Affluent Adolescent Females

ERIC Educational Resources Information Center

DeSilva Mousseau, Angela M.; Lund, Terese J.; Liang, Belle; Spencer, Renée; Walsh, Jill

2016-01-01

This study examined the relationship between stress and sleep duration for adolescent females from affluent backgrounds. Participants were 218 students attending two independent single-sex secondary schools. Ordinary Least Squares (OLS) regression models (cross-sectional and longitudinal) were run to examine the association between stress and…

Driving Task: How Older Drivers' On-Road Driving Performance Relates to Abilities, Perceptions, and Restrictions.

PubMed

Koppel, Sjaan; Charlton, Judith L; Langford, Jim; Di Stefano, Marilyn; MacDonald, Wendy; Vlahodimitrakou, Zafiroula; Mazer, Barbara L; Gelinas, Isabelle; Vrkljan, Brenda; Eliasz, Kinga; Myers, Anita; Tuokko, Holly A; Marshall, Shawn C

2016-06-01

This study examined a cohort of 227 older drivers and investigated the relationship between performance on the electronic Driver Observation Schedule (eDOS) driving task and: (1) driver characteristics; (2) functional abilities; (3) perceptions of driving comfort and abilities; and (4) self-reported driving restrictions. Participants (male: 70%; age: M = 81.53 years, SD = 3.37 years) completed a series of functional ability measures and scales on perceived driving comfort, abilities, and driving restrictions from the Year 2 Candrive/Ozcandrive assessment protocol, along with an eDOS driving task. Observations of participants' driving behaviours during the driving task were recorded for intersection negotiation, lane-changing, merging, low-speed maneuvers, and maneuver-free driving. eDOS driving task scores were high (M = 94.74; SD = 5.70) and significantly related to participants' perceived driving abilities, reported frequency of driving in challenging situations, and number of driving restrictions. Future analyses will explore potential changes in driving task scores over time.

Imperfect pitch: Gabor's uncertainty principle and the pitch of extremely brief sounds.

PubMed

Hsieh, I-Hui; Saberi, Kourosh

2016-02-01

How brief must a sound be before its pitch is no longer perceived? The uncertainty tradeoff between temporal and spectral resolution (Gabor's principle) limits the minimum duration required for accurate pitch identification or discrimination. Prior studies have reported that pitch can be extracted from sinusoidal pulses as brief as half a cycle. This finding has been used in a number of classic papers to develop models of pitch encoding. We have found that phase randomization, which eliminates timbre confounds, degrades this ability to chance, raising serious concerns over the foundation on which classic pitch models have been built. The current study investigated whether subthreshold pitch cues may still exist in partial-cycle pulses revealed through statistical integration in a time series containing multiple pulses. To this end, we measured frequency-discrimination thresholds in a two-interval forced-choice task for trains of partial-cycle random-phase tone pulses. We found that residual pitch cues exist in these pulses but discriminating them requires an order of magnitude (ten times) larger frequency difference than that reported previously, necessitating a re-evaluation of pitch models built on earlier findings. We also found that as pulse duration is decreased to less than two cycles its pitch becomes biased toward higher frequencies, consistent with predictions of an auto-correlation model of pitch extraction.

Time utilization and perceived psychosocial work environment among staff in Swedish primary care settings.

PubMed

Anskär, Eva; Lindberg, Malou; Falk, Magnus; Andersson, Agneta

2018-03-07

Over the past decades, reorganizations and structural changes in Swedish primary care have affected time utilization among health care professionals. Consequently, increases in administrative tasks have substantially reduced the time available for face-to-face consultations. This study examined how work-time was utilized and the association between work time utilization and the perceived psychosocial work environment in Swedish primary care settings. This descriptive, multicentre, cross-sectional study was performed in 2014-2015. Data collection began with questionnaire. In the first section, respondents were asked to estimate how their workload was distributed between patients (direct and indirect patient work) and other work tasks. The questionnaire also comprised the Copenhagen Psychosocial Questionnaire, which assessed the psychosocial work environment. Next a time study was conducted where the participants reported their work-time based on three main categories: direct patient-related work, indirect patient-related work, and other work tasks. Each main category had a number of subcategories. The participants recorded the time spent (minutes) on each work task per hour, every day, for two separate weeks. Eleven primary care centres located in southeast Sweden participated. All professionals were asked to participate (n = 441), including registered nurses, primary care physicians, care administrators, nurse assistants, and allied professionals. Response rates were 75% and 79% for the questionnaires and the time study, respectively. All health professionals allocated between 30.9% - 37.2% of their work-time to each main category: direct patient work, indirect patient work, and other work. All professionals estimated a higher proportion of time spent in direct patient work than they reported in the time study. Physicians scored highest on the psychosocial scales of quantitative demands, stress, and role conflicts. Among allied professionals, the proportion of work-time spent on administrative tasks was associated with more role conflicts. Younger staff perceived more adverse working conditions than older staff. This study indicated that Swedish primary care staff spent a limited proportion of their work time directly with patients. PCPs seemed to perceive their work environment in negative terms to a greater extent than other staff members. This study showed that work task allocations influenced the perceived psychosocial work environment.

Moving time: the influence of action on duration perception.

PubMed

Press, Clare; Berlot, Eva; Bird, Geoffrey; Ivry, Richard; Cook, Richard

2014-10-01

Perceiving the sensory consequences of action accurately is essential for appropriate interaction with our physical and social environments. Prediction mechanisms are considered necessary for fine-tuned sensory control of action, yet paradoxically may distort perception. Here, we examine this paradox by addressing how movement influences the perceived duration of sensory outcomes congruent with action. Experiment 1 required participants to make judgments about the duration of vibrations applied to a moving or stationary finger. In Experiments 2 and 3, participants judged observed finger movements that were congruent or incongruent with their own actions. In all experiments, target events were perceived to be longer when congruent with movement. Interestingly, this temporal dilation did not differ as a function of stimulus perspective (1st or 3rd person) or spatial location. We propose that this bias may reflect the operation of an adaptive mechanism for sensorimotor selection and control that preactivates anticipated outcomes of action. The bias itself may have surprising implications for both action control and perception of others: we may be in contact with grasped objects for less time than we realize, and others' reactions to us may be briefer than we believe.

Psychopathological profile and quality of life of patients with oral lichen planus.

PubMed

Radwan-Oczko, Małgorzata; Zwyrtek, Edyta; Owczarek, Joanna Elżbieta; Szcześniak, Dorota

2018-01-18

Oral lichen planus (OLP) is a chronic, multifocal, sometimes painful, inflammatory disease of the oral mucosa. OLP can predispose development of psycho-emotional disorders. Until now, the relationship between the severity of lichen planus and the psychological profile of patients (psychological well-being, perceived stress and pain coping strategies) has never been studied. Study was conducted on 42 OLP patients. Number of sites involved, severity and activity score of OLP were evaluated. Psychological tests were used to evaluate patients' psycho-emotional condition. The mean duration time of symptomatic OLP was 43 months. We detected that the longer the duration of subjective symptoms, the poorer the quality of life and the higher the level of perceived stress (PSS). Also, the higher the PSS results, the greater the anxiety and depression on Hospital Anxiety and Depression Scale (HADS). Likewise, higher level of depression in HADS was strongly correlated with worse quality of life. (p≤0.05). In this study, we detected a relationship between duration of the disease, level of perceived stress and quality of life. The longer the disease lasts, the higher it tends to catastrophize. This may influence development or increase of the anxiety and depression and may decrease patients' quality of life.

Practice and Experience of Task Management of University Students: Case of University of Tsukuba, Japan

ERIC Educational Resources Information Center

Fukuzawa, Ryoko; Joho, Hideo; Maeshiro, Tetsuya

2015-01-01

This paper reports the results of a survey that investigated the practice and experience of task management of university students. A total of 202 tasks identified by 24 university students were analyzed. The results suggest that participants had a reasonable sense of priority of tasks, that they tend to perceive a task as a big chunk, not a…

The Impact of Communication Mode and Task Complexity on Small Group Performance and Member Satisfaction.

ERIC Educational Resources Information Center

Carey, Jane M.; Kacmar, Charles, J.

1997-01-01

It is often presumed that software technology will increase group productivity, but this may not be the case. Examines the impact of technology on time-to-complete-task, member satisfaction, perceived information load, number of contributing transactions, and task complexity. Three appendices provide examples of complex and simple tasks and the…

A Demands-Resources Model of Work Pressure in IT Student Task Groups

ERIC Educational Resources Information Center

Wilson, E. Vance; Sheetz, Steven D.

2010-01-01

This paper presents an initial test of the group task demands-resources (GTD-R) model of group task performance among IT students. We theorize that demands and resources in group work influence formation of perceived group work pressure (GWP) and that heightened levels of GWP inhibit group task performance. A prior study identified 11 factors…

The Effects of Long-Duration Spaceflight on Training Retention and Transfer

NASA Technical Reports Server (NTRS)

Barshi, Immanuel; Healy, Alice; Dempsey, Donna L.; McGuire, Kerry M.; Landon, Lauren B.

2018-01-01

Training our crew members for long duration, exploration-class missions will have to maximize long-term retention and transfer of the trained skills. The expected duration of the missions, our inability to predict all the possible tasks the crew will be called upon to perform, and the low training-to-mission time ratio require that the training be maximally effective such that the skills acquired during training will be retained and will be transferrable across a wide range of specific tasks that are different from the particular tasks used during training. However, to be able to design training that can achieve these ambitious goals, we must first understand the ways in which long-duration spaceflight affects training retention and transfer. Current theories of training retention and transfer are largely based on experimental studies conducted at university laboratories using undergraduate students as participants. Furthermore, all such studies have been conducted on Earth. We do not know how well the results of these studies predict the performance of crew members. More specifically, we do not know how well the results of these studies predict the performance of crew members in space and especially during long-duration missions. To address this gap in our knowledge, the current on-going study seeks to test the null hypothesis that performance of university undergraduate students on Earth on training retention and transfer tests do in fact predict accurately the performance of crew members during long-duration spaceflights. To test this hypothesis, the study employs a single 16-month long experimental protocol with 3 different participant groups: undergraduate university students, crew members on the ground, and crew members in space. Results from this study will be presented upon its completion. This poster presents results of study trials of the two tasks used in this study: a data entry task and a mapping task. By researching established training principles, by examining future needs, and by using current practices in spaceflight training as test beds, this research project is mitigating program risks and generating templates and requirements to meet future training needs.

The Effects of Long-Duration Spaceflight on Training Retention and Transfer

NASA Technical Reports Server (NTRS)

Barshi, Immanuel; Healy, Alice; Dempsey, Donna L.; Mcguire, Kerry; Landon, Lauren

2017-01-01

Training our crew members for long duration, exploration-class missions will have to maximize long-term retention and transfer of the trained skills. The expected duration of the missions, our inability to predict all the possible tasks the crew will be called upon to perform, and the low training-to-mission time ratio require that the training be maximally effective such that the skills acquired during training will be retained and will be transferrable across a wide range of specific tasks that are different from the particular tasks used during training. However, to be able to design training that can achieve these ambitious goals, we must first understand the ways in which long-duration spaceflight affects training retention and transfer. Current theories of training retention and transfer are largely based on experimental studies conducted at university laboratories using undergraduate students as participants. Furthermore, all such studies have been conducted on Earth. We do not know how well the results of these studies predict the performance of crew members. More specifically, we do not know how well the results of these studies predict the performance of crew members in space and especially during long-duration missions. To address this gap in our knowledge, the current on-going study seeks to test the null hypothesis that performance of university undergraduate students on Earth on training retention and transfer tests do in fact predict accurately the performance of crew members during long-duration spaceflights. To test this hypothesis, the study employs a single 16-month long experimental protocol with 3 different participant groups: undergraduate university students, crew members on the ground, and crew members in space. Results from this study will be presented upon its completion. This poster presents results of study trials of the two tasks used in this study: a data entry task and a mapping task. By researching established training principles, by examining future needs, and by using current practices in spaceflight training as test beds, this research project is mitigating program risks and generating templates and requirements to meet future training needs.

Attentionally splitting the mass distribution of hand-held rods.

PubMed

Burton, G; Turvey, M T

1991-08-01

Two experiments on the length-perception capabilities of effortful or dynamic touch differed only in terms of what the subject intended to perceive, while experimental conditions and apparatus were held constant. In each trial, a visually occluded rod was held as still as possible by the subject at an intermediate position. For two thirds of the trials, a weight was attached to the rod above or below the hand. In Experiment 1, in which the subject's task was to perceive the distance reachable with the portion of the rod forward of the hand, perceived extent was a function of the first moment of the mass distribution associated with the forward portion of the rod, and indifferent to the first moment of the entire rod. In Experiment 2, in which the task was to perceive the distance reachable with the entire rod if it was held at an end, the pattern of results was reversed. These results indicate the capability of selective sensitivity to different aspects of a hand-held object's mass distribution, without the possibility of differential exploration specific to these two tasks. Results are discussed in relation to possible roles of differential information, intention, and self-organization in the explanations of selective perceptual abilities.

The Impact of Feedback Frequency on Performance in a Novel Speech Motor Learning Task.

PubMed

Lowe, Mara Steinberg; Buchwald, Adam

2017-06-22

This study investigated whether whole nonword accuracy, phoneme accuracy, and acoustic duration measures were influenced by the amount of feedback speakers without impairment received during a novel speech motor learning task. Thirty-two native English speakers completed a nonword production task across 3 time points: practice, short-term retention, and long-term retention. During practice, participants received knowledge of results feedback according to a randomly assigned schedule (100%, 50%, 20%, or 0%). Changes in nonword accuracy, phoneme accuracy, nonword duration, and initial-cluster duration were compared among feedback groups, sessions, and stimulus properties. All participants improved phoneme and whole nonword accuracy at short-term and long-term retention time points. Participants also refined productions of nonwords, as indicated by a decrease in nonword duration across sessions. The 50% group exhibited the largest reduction in duration between practice and long-term retention for nonwords with native and nonnative clusters. All speakers, regardless of feedback schedule, learned new speech motor behaviors quickly with a high degree of accuracy and refined their speech motor skills for perceptually accurate productions. Acoustic measurements may capture more subtle, subperceptual changes that may occur during speech motor learning. https://doi.org/10.23641/asha.5116324.

Assessing the influence of a passive, upper extremity exoskeletal vest for tasks requiring arm elevation: Part I - "Expected" effects on discomfort, shoulder muscle activity, and work task performance.

PubMed

Kim, Sunwook; Nussbaum, Maury A; Mokhlespour Esfahani, Mohammad Iman; Alemi, Mohammad Mehdi; Alabdulkarim, Saad; Rashedi, Ehsan

2018-03-07

Use of exoskeletal vests (designed to support overhead work) can be an effective intervention approach for tasks involving arm elevation, yet little is known on the potential beneficial impacts of their use on physical demands and task performance. This laboratory study (n = 12) evaluated the effects of a prototype exoskeletal vest during simulated repetitive overhead drilling and light assembly tasks. Anticipated or expected benefits were assessed, in terms of perceived discomfort, shoulder muscle activity, and task performance. Using the exoskeletal vest did not substantially influence perceived discomfort, but did decrease normalized shoulder muscle activity levels (e.g., ≤ 45% reduction in peak activity). Drilling task completion time decreased by nearly 20% with the vest, but the number of errors increased. Overall, exoskeletal vest use has the potential to be a new intervention for work requiring arm elevation; however, additional investigations are needed regarding potential unexpected or adverse influences (see Part II). Copyright © 2018 Elsevier Ltd. All rights reserved.

Virtual reality applications for motor rehabilitation after stroke.

PubMed

Sisto, Sue Ann; Forrest, Gail F; Glendinning, Diana

2002-01-01

Hemiparesis is the primary physical impairment underlying functional disability after stroke. A goal of rehabilitation is to enhance motor skill acquisition, which is a direct result of practice. However, frequency and duration of practice are limited in rehabilitation. Virtual reality (VR) is a computer technology that simulates real-life learning while providing augmented feedback and increased frequency, duration, and intensity of practiced tasks. The rate and extent of relearning of motor tasks could affect the duration, effectiveness, and cost of patient care. The purpose of this article is to review the use of VR training for motor rehabilitation after stroke.

Perceived Parenting Mediates Serotonin Transporter Gene (5-HTTLPR) and Neural System Function during Facial Recognition: A Pilot Study.

PubMed

Nishikawa, Saori; Toshima, Tamotsu; Kobayashi, Masao

2015-01-01

This study examined changes in prefrontal oxy-Hb levels measured by NIRS (Near-Infrared Spectroscopy) during a facial-emotion recognition task in healthy adults, testing a mediational/moderational model of these variables. Fifty-three healthy adults (male = 35, female = 18) aged between 22 to 37 years old (mean age = 24.05 years old) provided saliva samples, completed a EMBU questionnaire (Swedish acronym for Egna Minnen Beträffande Uppfostran [My memories of upbringing]), and participated in a facial-emotion recognition task during NIRS recording. There was a main effect of maternal rejection on RoxH (right frontal activation during an ambiguous task), and a gene × environment (G × E) interaction on RoxH, suggesting that individuals who carry the SL or LL genotype and who endorse greater perceived maternal rejection show less right frontal activation than SL/LL carriers with lower perceived maternal rejection. Finally, perceived parenting style played a mediating role in right frontal activation via the 5-HTTLPR genotype. Early-perceived parenting might influence neural activity in an uncertain situation i.e. rating ambiguous faces among individuals with certain genotypes. This preliminary study makes a small contribution to the mapping of an influence of gene and behaviour on the neural system. More such attempts should be made in order to clarify the links.

Perceived Parenting Mediates Serotonin Transporter Gene (5-HTTLPR) and Neural System Function during Facial Recognition: A Pilot Study

PubMed Central

Nishikawa, Saori

2015-01-01

This study examined changes in prefrontal oxy-Hb levels measured by NIRS (Near-Infrared Spectroscopy) during a facial-emotion recognition task in healthy adults, testing a mediational/moderational model of these variables. Fifty-three healthy adults (male = 35, female = 18) aged between 22 to 37 years old (mean age = 24.05 years old) provided saliva samples, completed a EMBU questionnaire (Swedish acronym for Egna Minnen Beträffande Uppfostran [My memories of upbringing]), and participated in a facial-emotion recognition task during NIRS recording. There was a main effect of maternal rejection on RoxH (right frontal activation during an ambiguous task), and a gene × environment (G×E) interaction on RoxH, suggesting that individuals who carry the SL or LL genotype and who endorse greater perceived maternal rejection show less right frontal activation than SL/LL carriers with lower perceived maternal rejection. Finally, perceived parenting style played a mediating role in right frontal activation via the 5-HTTLPR genotype. Early-perceived parenting might influence neural activity in an uncertain situation i.e. rating ambiguous faces among individuals with certain genotypes. This preliminary study makes a small contribution to the mapping of an influence of gene and behaviour on the neural system. More such attempts should be made in order to clarify the links. PMID:26418317

Goal orientation profile differences on perceived motivational climate, perceived peer relationships, and motivation-related responses of youth athletes.

PubMed

Smith, Alan L; Balaguer, Isabel; Duda, Joan L

2006-12-01

The aims of this study were twofold: (a) to determine if dispositional achievement goal orientation profiles that are reported in the literature would be observed in a sample of youth athletes, and (b) to examine potential achievement goal orientation profile differences on perceptions of the motivational climate, perceptions of peer relationships, and motivation-related responses. Male soccer players (n=223) aged 9-12 years (mean=10.9, s=0.6) completed a multi-section questionnaire containing assessments of dispositional goal (task, ego) orientations, the perceived task- and ego-involving features of the motivational climate, perceived peer acceptance and friendship quality (positive friendship quality, conflict), perceived ability, soccer enjoyment, and satisfaction with one's performance and the team. Four profiles were observed that closely matched those observed by Hodge and Petlichkoff (2000), though in the present study a lower proportion of participants exhibited achievement goal profiles consisting of relatively high ego orientation. Achievement goal profile differences were found for all variables except positive friendship quality, with a general trend for those reporting relatively lower task goal orientation to exhibit less adaptive responses. Overall, the findings support achievement goal frameworks (e.g. Nicholls, 1989) and suggest that further examination of dispositional achievement goals may afford a deeper understanding of social relationships and motivational processes in youth sport.

Ethnicity moderates the benefits of perceived support and emotional expressivity on stress reactivity for Asian Americans and Euro Americans.

PubMed

Wang, Shu-Wen; Lau, Anna S

2018-05-21

This study examined whether ethnicity moderated the benefits of perceived support and emotion expressivity on stress responses (cortisol, negative mood, task performance) during a lab stress task for Asian Americans and Euro Americans. We hypothesized that perceived support and emotion expressivity would be less beneficial for Asian Americans (relative to Euro Americans), for whom support seeking and emotional expressivity are less aligned with cultural values. A majority female sample (72%) of 83 Asian American (first generation, n = 30; second generation, n = 53) and 50 Euro American college students completed the Trier Social Stress Test. Participants provided baseline and poststressor measures of salivary cortisol and negative mood, and their task performance was coded by researchers. Results showed evidence of ethnic group moderation such that perceived support and emotional expressivity did not buffer biological, psychological, or behavioral stress outcomes for Asian Americans, but did offer some benefits to Euro Americans. The two groups differed on interdependence and acculturation, yet there was limited evidence that cultural variables moderated those same associations. Results counter the notion that perceived support and emotion expressivity are universal psychosocial resources for managing stress. This study highlights the importance of considering ethnic group differences in these socioemotional processes that are relevant for better understanding adaptive coping and well-being. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Is political behavior a viable coping strategy to perceived organizational politics? Unveiling the underlying resource dynamics.

PubMed

Sun, Shuhua; Chen, Huaizhong

2017-10-01

[Correction Notice: An Erratum for this article was reported in Vol 102(10) of Journal of Applied Psychology (see record 2017-34254-001). In the article, Table 1 contained a formatting error. Correlation coefficient values in the last four cells of column 6 were misplaced with correlation coefficient values in the last four cells of column 7. All versions of this article have been corrected.] We conduct a theory-driven empirical investigation on whether political behavior, as a coping strategy to perceived organizational politics, creates resource trade-offs in moderating the relationship between perceived organizational politics and task performance. Drawing on conservation of resources theory, we hypothesize that political behavior mitigates the adverse effect of perceived organizational politics on task performance via psychological empowerment, yet exacerbates its adverse effect on task performance via emotional exhaustion. Three-wave multisource data from a sample of 222 employees and their 75 supervisors were collected for hypothesis testing. Findings supported our hypotheses. Our study enhances understandings of the complex resource dynamics of using political behavior to cope with perceived organizational politics and highlights the need to move stress-coping research from a focus on the stress-buffering effect of coping on outcomes to a focus on the underlying competing resource dynamics. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Task Values, Cost, and Choice Decisions in College Physical Education

ERIC Educational Resources Information Center

Chen, Ang; Liu, Xinlan

2009-01-01

The expectancy-value motivation theory postulates that motivation can be achieved when perceived values in an activity override perceived cost of the activity derived from the effort of achieving. This study was designed to examine types of perceived cost in physical education and the extent to which the cost might affect motivation. Data about…

Visual context processing deficits in schizophrenia: effects of deafness and disorganization.

PubMed

Horton, Heather K; Silverstein, Steven M

2011-07-01

Visual illusions allow for strong tests of perceptual functioning. Perceptual impairments can produce superior task performance on certain tasks (i.e., more veridical perception), thereby avoiding generalized deficit confounds while tapping mechanisms that are largely outside of conscious control. Using a task based on the Ebbinghaus illusion, a perceptual phenomenon where the perceived size of a central target object is affected by the size of surrounding inducers, we tested hypotheses related to visual integration in deaf (n = 31) and hearing (n = 34) patients with schizophrenia. In past studies, psychiatrically healthy samples displayed increased visual integration relative to schizophrenia samples and thus were less able to correctly judge target sizes. Deafness, and especially the use of sign language, leads to heightened sensitivity to peripheral visual cues and increased sensitivity to visual context. Therefore, relative to hearing subjects, deaf subjects were expected to display increased context sensitivity (ie, a more normal illusion effect as evidenced by a decreased ability to correctly judge central target sizes). Confirming the hypothesis, deaf signers were significantly more sensitive to the illusion than nonsigning hearing patients. Moreover, an earlier age of sign language acquisition, higher levels of linguistic ability, and shorter illness duration were significantly related to increased context sensitivity. As predicted, disorganization was associated with reduced context sensitivity for all subjects. The primary implications of these data are that perceptual organization impairment in schizophrenia is plastic and that it is related to a broader failure in coordinating cognitive activity.

Perception of social interaction compresses subjective duration in an oxytocin-dependent manner

PubMed Central

2018-01-01

Communication through body gestures permeates our daily life. Efficient perception of the message therein reflects one’s social cognitive competency. Here we report that such competency is manifested temporally as shortened subjective duration of social interactions: motion sequences showing agents acting communicatively are perceived to be significantly shorter in duration as compared with those acting noncommunicatively. The strength of this effect is negatively correlated with one’s autistic-like tendency. Critically, intranasal oxytocin administration restores the temporal compression effect in socially less proficient individuals, whereas the administration of atosiban, a competitive antagonist of oxytocin, diminishes the effect in socially proficient individuals. These findings indicate that perceived time, rather than being a faithful representation of physical time, is highly idiosyncratic and ingrained with one’s personality trait. Moreover, they suggest that oxytocin is involved in mediating time perception of social interaction, further supporting the role of oxytocin in human social cognition. PMID:29784084

SEL and EPNL noise duration coefficients for the 747 and T-38 aircraft

NASA Technical Reports Server (NTRS)

Willshire, W. L., Jr.

1981-01-01

Duration coefficient were calculated for Boeing 747 and T-38 airplanes for sound exposure level (SEL) and effective perceived noise level (EPNL) scales. The measured SEL suration coefficients were 8.4 for the Boeing 747 and 5.5 for the T-38 result was in good agreement with a previous result for a similar F-5 airplane. In EPNL, the duration coefficients were 7.2 for the Boeing 747 and 5.7 for the T-38. The difference in the results between the two airplanes is believed to be due to their different engine noise source spectra. The difference in the Boeing 747 results in the two different metric was due to the different frequency weighting of A-weighted sound pressure level, used in SEL, and tone-corrected perceived noise level, used in EPNL, when applied to the 747 spectra.

Perception of social interaction compresses subjective duration in an oxytocin-dependent manner.

PubMed

Liu, Rui; Yuan, Xiangyong; Chen, Kepu; Jiang, Yi; Zhou, Wen

2018-05-22

Communication through body gestures permeates our daily life. Efficient perception of the message therein reflects one's social cognitive competency. Here we report that such competency is manifested temporally as shortened subjective duration of social interactions: motion sequences showing agents acting communicatively are perceived to be significantly shorter in duration as compared with those acting noncommunicatively. The strength of this effect is negatively correlated with one's autistic-like tendency. Critically, intranasal oxytocin administration restores the temporal compression effect in socially less proficient individuals, whereas the administration of atosiban, a competitive antagonist of oxytocin, diminishes the effect in socially proficient individuals. These findings indicate that perceived time, rather than being a faithful representation of physical time, is highly idiosyncratic and ingrained with one's personality trait. Moreover, they suggest that oxytocin is involved in mediating time perception of social interaction, further supporting the role of oxytocin in human social cognition. © 2018, Liu et al.

Perceived Neighborhood Safety Is Associated with Poor Sleep Health among Gay, Bisexual, and Other Men Who Have Sex with Men in Paris, France.

PubMed

Duncan, Dustin T; Park, Su Hyun; Goedel, William C; Kreski, Noah T; Morganstein, Jace G; Hambrick, H Rhodes; Jean-Louis, Girardin; Chaix, Basile

2017-06-01

Recent studies have examined sleep health among men who have sex with men (MSM), but no studies have examined associations of neighborhood characteristics and sleep health among this population. The purpose of this study was to examine associations between perceived neighborhood safety and sleep health among a sample of MSM in Paris, France. We placed broadcast advertisements on a popular smartphone application for MSM in October 2016 to recruit users in the Paris (France) metropolitan area (n = 580). Users were directed to complete a web-based survey, including previously used items measuring perceptions of neighborhood safety, validated measures of sleep health, and socio-demographics. Modified Poisson models were used to estimate risk ratios (RRs) and 95% confidence intervals (CI) for the associations between perceived neighborhood safety and the following outcomes: (1) poor sleep quality, (2) short sleep duration, and (3) self-reported sleep problems. Poor sleep health was common in our sample; e.g., 30.1% reported poor sleep quality and 44.7% reported problems falling asleep. In multivariate regression models, perceived neighborhood safety was associated with poor sleep quality, short sleep duration, and having sleep problems. For example, reporting living in a neighborhood perceived as unsafe during the daytime (vs. safe) was associated with poor sleep quality (aRR, 1.60; 95% CI, 1.01, 2.52), short sleep duration (aRR, 1.92; 95% CI, 1.26, 2.94), problems falling asleep (aRR, 1.57; 95% CI, 1.17, 2.11), and problems staying awake in the daytime (aRR, 2.16; 95% CI, 1.05, 4.43). Interventions to increase neighborhood safety may improve sleep health among MSM.

High School Athletes' Perceptions of the Motivational Climate in Their Off-Season Training Programs.

PubMed

Chamberlin, Jacob M; Fry, Mary D; Iwasaki, Susumu

2017-03-01

Chamberlin, JM, Fry, MD, and Iwasaki, S. High school athletes' perceptions of the motivational climate in their off-season training programs. J Strength Cond Res 31(3): 736-742, 2017-Athletes benefit tremendously from working hard in off-season training (OST) because it sets them up to avoid injuries and perform their best during the season. Ironically, many athletes struggle to stay motivated to participate regularly in this training. Research has highlighted the benefits for athletes perceiving a caring and task-involving climate, where they gauge their success based on their personal effort and improvement, and perceive each member of the team is treated with mutual kindness and respect. Athletes who perceive a caring and task-involving climate on their teams are more likely to report greater adaptive motivational responses. Research has not currently examined athletes' perceptions of the climate in OST programs. The purpose of this study was to examine the relationship between athletes' perceptions of the climate in an OST program and their motivational responses. High school athletes (N = 128; 90 males 35 females; mean age = 15.3 years) participating in summer OST programs completed a survey that included measures of intrinsic motivation, commitment, their valuing OST, feeling like it is their decision to participate in OST, their perceptions that their teammates take OST seriously, and attendance. A canonical correlation revealed that athletes, who perceived a highly caring and task-involving climate reported higher intrinsic motivation, value of and commitment to OST; attendance; and perceived teammates take OST seriously. Results suggest that creating a caring and task-involving climate in OST programs may help athletes optimize their motivation to participate in important strength and conditioning programs.

The idiosyncratic nature of confidence

PubMed Central

Navajas, Joaquin; Hindocha, Chandni; Foda, Hebah; Keramati, Mehdi; Latham, Peter E; Bahrami, Bahador

2017-01-01

Confidence is the ‘feeling of knowing’ that accompanies decision making. Bayesian theory proposes that confidence is a function solely of the perceived probability of being correct. Empirical research has suggested, however, that different individuals may perform different computations to estimate confidence from uncertain evidence. To test this hypothesis, we collected confidence reports in a task where subjects made categorical decisions about the mean of a sequence. We found that for most individuals, confidence did indeed reflect the perceived probability of being correct. However, in approximately half of them, confidence also reflected a different probabilistic quantity: the perceived uncertainty in the estimated variable. We found that the contribution of both quantities was stable over weeks. We also observed that the influence of the perceived probability of being correct was stable across two tasks, one perceptual and one cognitive. Overall, our findings provide a computational interpretation of individual differences in human confidence. PMID:29152591

Differences in phonetic discrimination stem from differences in psychoacoustic abilities in learning the sounds of a second language: Evidence from ERP research.

PubMed

Lin, Yi; Fan, Ruolin; Mo, Lei

2017-01-01

The scientific community has been divided as to the origin of individual differences in perceiving the sounds of a second language (L2). There are two alternative explanations: a general psychoacoustic origin vs. a speech-specific one. A previous study showed that such individual variability is linked to the perceivers' speech-specific capabilities, rather than the perceivers' psychoacoustic abilities. However, we assume that the selection of participants and parameters of sound stimuli might not appropriate. Therefore, we adjusted the sound stimuli and recorded event-related potentials (ERPs) from two groups of early, proficient Cantonese (L1)-Mandarin (L2) bilinguals who differed in their mastery of the Mandarin (L2) phonetic contrast /in-ing/, to explore whether the individual differences in perceiving L2 stem from participants' ability to discriminate various pure tones (frequency, duration and pattern). To precisely measure the participants' acoustic discrimination, mismatch negativity (MMN) elicited by the oddball paradigm was recorded in the experiment. The results showed that significant differences between good perceivers (GPs) and poor perceivers (PPs) were found in the three general acoustic conditions (frequency, duration and pattern), and the MMN amplitude for GP was significantly larger than for PP. Therefore, our results support a general psychoacoustic origin of individual variability in L2 phonetic mastery.

Transfer of motor and perceptual skills from basketball to darts

PubMed Central

Rienhoff, Rebecca; Hopwood, Melissa J.; Fischer, Lennart; Strauss, Bernd; Baker, Joseph; Schorer, Jörg

2013-01-01

The quiet eye is a perceptual skill associated with expertise and superior performance; however, little is known about the transfer of quiet eye across domains. We attempted to replicate previous skill-based differences in quiet eye and investigated whether transfer of motor and perceptual skills occurs between similar tasks. Throwing accuracy and quiet eye duration for skilled and less-skilled basketball players were examined in basketball free throw shooting and the transfer task of dart throwing. Skilled basketball players showed significantly higher throwing accuracy and longer quiet eye duration in the basketball free throw task compared to their less-skilled counterparts. Further, skilled basketball players showed positive transfer from basketball to dart throwing in accuracy but not in quiet eye duration. Our results raise interesting questions regarding the measurement of transfer between skills. PMID:24062703

Household responsibilities, income, and ambulatory blood pressure among working men and women

PubMed Central

Thurston, Rebecca C.; Sherwood, Andrew; Matthews, Karen A.; Blumenthal, James A.

2011-01-01

Objective To test the hypothesis that a greater perceived responsibility for household tasks and a greater number of hours spent doing these tasks would be associated with elevated ambulatory systolic (SBP) and diastolic blood pressure (DBP). The connection between job characteristics and cardiovascular outcomes has been widely studied. However, less is known about links between household work characteristics and cardiovascular health. Methods 113 employed unmedicated hypertensive men and women underwent one day of ambulatory blood pressure (ABP) monitoring. Participants provided information on 1) the number of hours spent doing and 2) their degree of responsibility for seven household tasks (child care, pet care, caring for ill/elderly, household chores, house/car repair, yardwork, finances). Associations between task hours and responsibility ratings in relation to SBP and DBP were estimated using generalized estimating equations, with covariates age, race, gender, body mass index, location, posture. Interactions with gender and socioeconomic position were assessed. Results A greater perceived responsibility for household tasks, but not the hours spent doing these tasks, was associated with higher ambulatory SBP (b(95% confidence interval (CI))=0.93(0.29–1.56), p=0.004) and DBP (b(95%CI)=0.30(0.10–0.51), p=0.003)). Significant interactions with income indicated that associations between household responsibilities and ABP were most pronounced among low income participants (SBP: b(95%CI)=1.40(0.58–2.21), p<0.001; DBP: b(95%CI)=0.48(0.18–0.78), p<0.01). The task most strongly associated with BP was household chores. No interactions with gender were observed. Conclusions Greater perceived responsibility for household tasks was associated with elevated ABP, particularly for lower income participants. Household obligations may have important implications for cardiovascular health, meriting further empirical attention. PMID:21217097

Pleasantness of Creative Tasks and Creative Performance

ERIC Educational Resources Information Center

Zenasni, Franck; Lubart, Todd

2011-01-01

To examine the impact of emotion on creative potential, experimental studies have typically focused on the impact of induced or spontaneous mood states on creative performance. In this report the relationship between the perceived pleasantness of tasks (using divergent thinking and story writing tasks) and creative performance was examined.…

"Is political behavior a viable coping strategy to perceived organizational politics? Unveiling the underlying resource dynamics": Correction to Sun and Chen (2017).

PubMed

2017-10-01

Reports an error in "Is Political Behavior a Viable Coping Strategy to Perceived Organizational Politics? Unveiling the Underlying Resource Dynamics" by Shuhua Sun and Huaizhong Chen ( Journal of Applied Psychology , Advanced Online Publication, May 22, 2017, np). In the article, Table 1 contained a formatting error. Correlation coefficient values in the last four cells of column 6 were misplaced with correlation coefficient values in the last four cells of column 7. All versions of this article have been corrected. (The following abstract of the original article appeared in record 2017-22542-001.) We conduct a theory-driven empirical investigation on whether political behavior, as a coping strategy to perceived organizational politics, creates resource trade-offs in moderating the relationship between perceived organizational politics and task performance. Drawing on conservation of resources theory, we hypothesize that political behavior mitigates the adverse effect of perceived organizational politics on task performance via psychological empowerment, yet exacerbates its adverse effect on task performance via emotional exhaustion. Three-wave multisource data from a sample of 222 employees and their 75 supervisors were collected for hypothesis testing. Findings supported our hypotheses. Our study enhances understandings of the complex resource dynamics of using political behavior to cope with perceived organizational politics and highlights the need to move stress-coping research from a focus on the stress-buffering effect of coping on outcomes to a focus on the underlying competing resource dynamics. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

The Effects of Numerical Magnitude, Size, and Color Saturation on Perceived Interval Duration

ERIC Educational Resources Information Center

Alards-Tomalin, Doug; Leboe-McGowan, Jason P.; Shaw, Joshua D. M.; Leboe-McGowan, Launa C.

2014-01-01

The relative magnitude (or intensity) of an event can have direct implications on timing estimation. Previous studies have found that greater magnitude stimuli are often reported as longer in duration than lesser magnitudes, including Arabic digits (Xuan, Zhang, He, & Chen, 2007). One explanation for these findings is that different…

Sleep duration and ischemic heart disease and all-cause mortality: prospective cohort study on effects of tranquilizers/hypnotics and perceived stress.

PubMed

Garde, Anne Helene; Hansen, Åse Marie; Holtermann, Andreas; Gyntelberg, Finn; Suadicani, Poul

2013-11-01

This prospective study aimed to examine if sleep duration is a risk indicator for ischemic heart disease (IHD) and all-cause mortality, and how perceived stress during work and leisure time and use of tranquilizers/hypnotics modifies the association. A 30-year follow-up study was carried out in the Copenhagen Male Study comprising 5249 men (40-59 years old). Confounders included lifestyle factors (smoking, alcohol, and leisure-time physical activity), clinical and health-related factors (body mass index, blood pressure, diabetes, hypertension, and physical fitness) and social class. Men with a history of cardiovascular disease at baseline were excluded. During follow-up, 587 men (11.9%) died from IHD and 2663 (53.9%) due to all-cause mortality. There were 276 short (<6 hours), 3837 medium (6-7 hours), and 828 long (≥8 hours) sleepers. Men who slept <6 hours had an increased risk of IHD mortality but not all-cause mortality, when referencing medium sleepers. Perceived psychological pressure during work and leisure was not a significant effect modifier for the association between sleep duration and IHD mortality. In contrast, among men using tranquilizers/hypnotics (rarely or regularly), short sleepers had a two-to-three fold increased risk of IHD mortality compared to medium sleepers. Among those never using tranquilizers/hypnotics, no association was observed between sleep duration and IHD mortality. Short sleep duration is a risk factor for IHD mortality among middle-aged and elderly men, particularly those using tranquilizers/hypnotics on a regular or even a rare basis, but not among men not using tranquilizers/hypnotics.

Bringing Reading-to-Write and Writing-Only Assessment Tasks Together: A Generalizability Analysis

ERIC Educational Resources Information Center

Gebril, Atta

2010-01-01

Integrated tasks are currently employed in a number of L2 exams since they are perceived as an addition to the writing-only task type. Given this trend, the current study investigates composite score generalizability of both reading-to-write and writing-only tasks. For this purpose, a multivariate generalizability analysis is used to investigate…

Eye movements during information processing tasks: individual differences and cultural effects.

PubMed

Rayner, Keith; Li, Xingshan; Williams, Carrick C; Cave, Kyle R; Well, Arnold D

2007-09-01

The eye movements of native English speakers, native Chinese speakers, and bilingual Chinese/English speakers who were either born in China (and moved to the US at an early age) or in the US were recorded during six tasks: (1) reading, (2) face processing, (3) scene perception, (4) visual search, (5) counting Chinese characters in a passage of text, and (6) visual search for Chinese characters. Across the different groups, there was a strong tendency for consistency in eye movement behavior; if fixation durations of a given viewer were long on one task, they tended to be long on other tasks (and the same tended to be true for saccade size). Some tasks, notably reading, did not conform to this pattern. Furthermore, experience with a given writing system had a large impact on fixation durations and saccade lengths. With respect to cultural differences, there was little evidence that Chinese participants spent more time looking at the background information (and, conversely less time looking at the foreground information) than the American participants. Also, Chinese participants' fixations were more numerous and of shorter duration than those of their American counterparts while viewing faces and scenes, and counting Chinese characters in text.

Sustained attention in language production: an individual differences investigation.

PubMed

Jongman, Suzanne R; Roelofs, Ardi; Meyer, Antje S

2015-01-01

Whereas it has long been assumed that most linguistic processes underlying language production happen automatically, accumulating evidence suggests that these processes do require some form of attention. Here we investigated the contribution of sustained attention: the ability to maintain alertness over time. In Experiment 1, participants' sustained attention ability was measured using auditory and visual continuous performance tasks. Subsequently, employing a dual-task procedure, participants described pictures using simple noun phrases and performed an arrow-discrimination task while their vocal and manual response times (RTs) and the durations of their gazes to the pictures were measured. Earlier research has demonstrated that gaze duration reflects language planning processes up to and including phonological encoding. The speakers' sustained attention ability correlated with the magnitude of the tail of the vocal RT distribution, reflecting the proportion of very slow responses, but not with individual differences in gaze duration. This suggests that sustained attention was most important after phonological encoding. Experiment 2 showed that the involvement of sustained attention was significantly stronger in a dual-task situation (picture naming and arrow discrimination) than in simple naming. Thus, individual differences in maintaining attention on the production processes become especially apparent when a simultaneous second task also requires attentional resources.

Subjective cognitive complaints and neuropsychological performance in former smokers with and without chronic obstructive pulmonary disease.

PubMed

Brunette, Amanda M; Holm, Kristen E; Wamboldt, Frederick S; Kozora, Elizabeth; Moser, David J; Make, Barry J; Crapo, James D; Meschede, Kimberly; Weinberger, Howard D; Moreau, Kerrie L; Bowler, Russell P; Hoth, Karin F

2018-05-01

This study examined the association of perceived cognitive difficulties with objective cognitive performance in former smokers. We hypothesized that greater perceived cognitive difficulties would be associated with poorer performance on objective executive and memory tasks. Participants were 95 former smokers recruited from the COPDGene study. They completed questionnaires (including the Cognitive Difficulties Scale [CDS] and the Hospital Anxiety and Depression Scale [HADS]), neuropsychological assessment, and pulmonary function testing. Pearson correlations and t-tests were conducted to examine the bivariate association of the CDS (total score and subscales for attention/concentration, praxis, delayed recall, orientation for persons, temporal orientation, and prospective memory) with each domain of objective cognitive functioning (memory recall, executive functioning/processing speed, visuospatial processing, and language). Simultaneous multiple linear regression was used to further examine all statistically significant bivariate associations. The following covariates were included in all regression models: age, sex, pack-years, premorbid functioning (WRAT-IV Reading), HADS total score, and chronic obstructive pulmonary disease (COPD) status (yes/no based on GOLD criteria). In regression models, greater perceived cognitive difficulties overall (using CDS total score) were associated with poorer performance on executive functioning/processing speed tasks (b = -0.07, SE = 0.03, p = .037). Greater perceived cognitive difficulties on the CDS praxis subscale were associated with poorer performance on executive functioning/processing speed tasks (b = -3.65, SE = 1.25, p = .005), memory recall tasks (b = -4.60, SE = 1.75, p = .010), and language tasks (b = -3.89, SE = 1.39, p = .006). Clinicians should be aware that cognitive complaints may be indicative of problems with the executive functioning/processing speed and memory of former smokers with and without COPD.

Quantifying the impact of cross coverage on physician's workload and performance in radiation oncology.

PubMed

Mosaly, Prithima R; Mazur, Lukasz M; Jones, Ellen L; Hoyle, Lesley; Zagar, Timothy; Chera, Bhishamjit S; Marks, Lawrence B

2013-01-01

To quantitatively assess the difference in workload and performance of radiation oncology physicians during radiation therapy treatment planning tasks under the conditions of "cross coverage" versus planning a patient with whom they were familiar. Eight physicians (3 experienced faculty physicians and 5 physician residents) performed 2 cases. The first case represented a "cross-coverage" scenario where the physicians had no prior information about the case to be planned. The second exposure represented a "regular-coverage" scenario where the physicians were familiar with the patient case to be planned. Each case involved 3 tasks to be completed systematically. Workload was assessed both subjectively (perceived) using National Aeronautics and Space Administration-Task Load Index (NASA-TLX), and objectively (physiological) throughout the task using eye data (via monitoring pupil size and blink rate). Performance of each task and the case was measured using completion time. Subjective willingness to approve or disapprove the generated plan was obtained after completion of the case only. Forty-eight perceived and 48 physiological workload assessments were obtained. Overall, results revealed a significant increase in perceived workload (high NASA-TLX score) and decrease in performance (longer completion time and reduced approval rate) during cross coverage. There were nonsignificant increases in pupil diameter and decreases in the blink rate during cross-coverage versus regular-coverage scenario. In both cross-coverage and regular-coverage scenarios the level of experience did not affect workload and performance. The cross-coverage scenario significantly increases perceived workload and degrades performance versus regular coverage. Hence, to improve patient safety, efforts must be made to develop policies, standard operating procedures, and usability improvements to electronic medical record and treatment planning systems for "easier" information processing to deal with cross coverage, while recognizing strengths and limitations of human performance. Published by Elsevier Inc.

Cognitive abilities required in time judgment depending on the temporal tasks used: A comparison of children and adults.

PubMed

Droit-Volet, S; Wearden, J H; Zélanti, P S

2015-01-01

The aim of this study was to examine age-related differences in time judgments during childhood as a function of the temporal task used. Children aged 5 and 8 years, as well as adults, were submitted to 3 temporal tasks (bisection, generalization and reproduction) with short (0.4/0.8 s) and long durations (8/16 s). Furthermore, their cognitive capacities in terms of working memory, attentional control, and processing speed were assessed by a wide battery of neuropsychological tests. The results showed that the age-related differences in time judgment were greater in the reproduction task than in the temporal discrimination tasks. This task was indeed more demanding in terms of working memory and information processing speed. In addition, the bisection task appeared to be easier for children than the generalization task, whereas these 2 tasks were similar for the adults, although the generalization task required more attention to be paid to the processing of durations. Our study thus demonstrates that it is important to understand the different cognitive processes involved in time judgment as a function of the temporal tasks used before venturing to draw conclusions about the development of time perception capabilities.

The Timing and Effort of Lexical Access in Natural and Degraded Speech

PubMed Central

Wagner, Anita E.; Toffanin, Paolo; Başkent, Deniz

2016-01-01

Understanding speech is effortless in ideal situations, and although adverse conditions, such as caused by hearing impairment, often render it an effortful task, they do not necessarily suspend speech comprehension. A prime example of this is speech perception by cochlear implant users, whose hearing prostheses transmit speech as a significantly degraded signal. It is yet unknown how mechanisms of speech processing deal with such degraded signals, and whether they are affected by effortful processing of speech. This paper compares the automatic process of lexical competition between natural and degraded speech, and combines gaze fixations, which capture the course of lexical disambiguation, with pupillometry, which quantifies the mental effort involved in processing speech. Listeners’ ocular responses were recorded during disambiguation of lexical embeddings with matching and mismatching durational cues. Durational cues were selected due to their substantial role in listeners’ quick limitation of the number of lexical candidates for lexical access in natural speech. Results showed that lexical competition increased mental effort in processing natural stimuli in particular in presence of mismatching cues. Signal degradation reduced listeners’ ability to quickly integrate durational cues in lexical selection, and delayed and prolonged lexical competition. The effort of processing degraded speech was increased overall, and because it had its sources at the pre-lexical level this effect can be attributed to listening to degraded speech rather than to lexical disambiguation. In sum, the course of lexical competition was largely comparable for natural and degraded speech, but showed crucial shifts in timing, and different sources of increased mental effort. We argue that well-timed progress of information from sensory to pre-lexical and lexical stages of processing, which is the result of perceptual adaptation during speech development, is the reason why in ideal situations speech is perceived as an undemanding task. Degradation of the signal or the receiver channel can quickly bring this well-adjusted timing out of balance and lead to increase in mental effort. Incomplete and effortful processing at the early pre-lexical stages has its consequences on lexical processing as it adds uncertainty to the forming and revising of lexical hypotheses. PMID:27065901

Compensation for pitch-shifted auditory feedback during the production of Mandarin tone sequences

NASA Astrophysics Data System (ADS)

Xu, Yi; Larson, Charles R.; Bauer, Jay J.; Hain, Timothy C.

2004-08-01

Recent research has found that while speaking, subjects react to perturbations in pitch of voice auditory feedback by changing their voice fundamental frequency (F0) to compensate for the perceived pitch-shift. The long response latencies (150-200 ms) suggest they may be too slow to assist in on-line control of the local pitch contour patterns associated with lexical tones on a syllable-to-syllable basis. In the present study, we introduced pitch-shifted auditory feedback to native speakers of Mandarin Chinese while they produced disyllabic sequences /ma ma/ with different tonal combinations at a natural speaking rate. Voice F0 response latencies (100-150 ms) to the pitch perturbations were shorter than syllable durations reported elsewhere. Response magnitudes increased from 50 cents during static tone to 85 cents during dynamic tone productions. Response latencies and peak times decreased in phrases involving a dynamic change in F0. The larger response magnitudes and shorter latency and peak times in tasks requiring accurate, dynamic control of F0, indicate this automatic system for regulation of voice F0 may be task-dependent. These findings suggest that auditory feedback may be used to help regulate voice F0 during production of bi-tonal Mandarin phrases.

Predictors of Depressive Symptoms in Caregivers of Patients with Heart Failure

PubMed Central

Chung, Misook L.; Pressler, Susan J.; Dunbar, Sandra B.; Lennie, Terry A.; Moser, Debra K.; Endowed, Gill

2010-01-01

Background Millions of family members deliver informal care and support to patients with heart failure (HF). Caregivers of patients with HF suffer from depressive symptoms, but factors associated with depressive symptoms are unknown. The purposes of this study were (1) to examine differences between caregivers with and without depressive symptoms in patients’ characteristics and caregivers’ functional status, caregiving burden (time devoted to caregiving, difficulty of caregiving tasks, and overall perceived caregiving distress), and perceived control; and (2) to determine predictors of depressive symptoms of caregivers. Method A total of 109 caregivers (mean age of 57 years; spousal caregiver 79%) and patients with HF participated in this study. Depressive symptoms, perceived control, and functional status of both patients and caregivers were assessed using the Beck Depression Inventory-II (BDI-II), the Control Attitudes Scale-Revised, and the Duke Activity Status Index, respectively. Caregivers’ burden (time and difficulty of caregiving tasks and burden) were assessed using the Oberst Caregiving Burden Scale, and the Zarit Burden Interview. Results The 27.5% of HF caregivers with depressive symptoms (BDI-II ≥ 14) had poorer functional status, lower perceived control, higher perceived caregiving distress, experienced more caregiving difficulty and spent more time in caregiving tasks than caregivers without depressive symptoms. Controlling for age and gender in a multiple regression, caregivers’ own functional disability (sβ = -.307, P < .001), perceived control (sβ = -.304, P < .001), and caregiver burden (sβ =.316, P = .002) explained 45% of the variance in caregivers’ depressive symptoms. Patients’ NYHA class and functional status did not predict caregivers’ depressive symptoms. Conclusion Caregivers’ poor functional status, overall perception of caregiving distress, and perceived control were associated with depressive symptoms. Depressed caregivers of patients with HF may benefit from interventions that improve caregivers’ perceived control, address the caregiving burden and improve or assist with caregivers’ functional status. PMID:20714239

The influence of social support and perceived stress on response time inconsistency.

PubMed

Phibbs, Sandi; Stawski, Robert S; MacDonald, Stuart W S; Munoz, Elizabeth; Smyth, Joshua M; Sliwinski, Martin J

2017-11-24

Lack of social support and high levels of stress represent potentially modifiable risk factors for cognitive aging. In this study we examined the relationships between these two risk factors and response time inconsistency (RTI), or trial-to-trial variability in choice response time tasks. RTI is an early indicator of declining cognitive health, and examining the influence of modifiable psychosocial risk factors on RTI is important for understanding and promoting cognitive health during adulthood and old age. Using data from a community sample study (n = 317; M age = 49, range = 19-83), we examined the effects of social support, including size of network and satisfaction with support, global perceived stress, and their interactions on RTI. Neither size of network nor satisfaction with support was associated with RTI independent of perceived stress. Stress was positively associated with increased RTI on all tasks, independent of social support. Perceived stress did not interact with either dimension of social support to predict RTI, and perceived stress effects were invariant across age and sex. Perceived stress, but not social support, may be a unique and modifiable risk factor for normal and pathological cognitive aging. Discussion focuses on the importance of perceived stress and its impact on RTI in supporting cognitive health in adulthood and old age.

Perceived social acceptance, theory of mind and social adjustment in children with intellectual disabilities.

PubMed

Fiasse, Catherine; Nader-Grosbois, Nathalie

2012-01-01

Perceived social acceptance, theory of mind (ToM) and social adjustment were investigated in 45 children with intellectual disabilities (ID) compared with 45 typically developing (TD) preschoolers, matched for developmental age assessed by means of the Differential Scales of Intellectual Efficiency-Revised edition (EDEI-R, Perron-Borelli, 1996). Children's understanding of beliefs and emotions was assessed by means of ToM belief tasks (Nader-Grosbois & Thirion-Marissiaux, 2011) and ToM emotion tasks (Nader-Grosbois & Thirion-Marissiaux, 2011). Seven items from the Pictorial Scale of Perceived Competence and Social Acceptance for children (PSPCSA, Harter & Pike, 1980) assessed children's perceived social acceptance. Their teachers completed the Social Adjustment for Children Scale (EASE, Hughes, Soares-Boucaud, Hochmann, & Frith, 1997). For both groups together, the results showed that perceived social acceptance mediates the relation between ToM skills and social adjustment. The presence or absence of intellectual disabilities does not moderate the relations either between ToM skills and perceived social acceptance, or between perceived social acceptance and social adjustment. The study did not confirm the difference hypothesis of structural and relational patterns between these three processes in children with ID, but instead supported the hypothesis of a similar structure that develops in a delayed manner. Copyright © 2012 Elsevier Ltd. All rights reserved.

Development of task network models of human performance in microgravity

NASA Technical Reports Server (NTRS)

Diaz, Manuel F.; Adam, Susan

1992-01-01

This paper discusses the utility of task-network modeling for quantifying human performance variability in microgravity. The data are gathered for: (1) improving current methodologies for assessing human performance and workload in the operational space environment; (2) developing tools for assessing alternative system designs; and (3) developing an integrated set of methodologies for the evaluation of performance degradation during extended duration spaceflight. The evaluation entailed an analysis of the Remote Manipulator System payload-grapple task performed on many shuttle missions. Task-network modeling can be used as a tool for assessing and enhancing human performance in man-machine systems, particularly for modeling long-duration manned spaceflight. Task-network modeling can be directed toward improving system efficiency by increasing the understanding of basic capabilities of the human component in the system and the factors that influence these capabilities.

Dynamics of Perceived Exertion in Constant-Power Cycling: Time- and Workload-Dependent Thresholds

ERIC Educational Resources Information Center

Balagué, Natàlia; Hristovski, Robert; García, Sergi; Aguirre, Cecilia; Vázquez, Pablo; Razon, Selen; Tenenbaum, Gershon

2015-01-01

Purpose: The purpose of this study was to test the dynamics of perceived exertion shifts (PES) as a function of time and workload during constant-power cycling. Method: Fifty-two participants assigned to 4 groups performed a cycling task at 4 different constant workloads corresponding to their individual rates of perceived exertion (RPEs = 13, 15,…

Workplace ostracism And workplace behaviors: A moderated mediation model of perceived stress and psychological empowerment.

PubMed

Chung, Yang Woon

2018-05-01

Workplace ostracism research has examined numerous underlying mechanisms to understand the link between workplace ostracism and behavioral outcomes. Ostracism has been suggested to be an interpersonal stressor; however, research has not investigated workplace ostracism from a stress perspective. Therefore, the study investigated the mediating effect of perceived stress for the relationships between workplace ostracism and helping behavior, voicing behavior, and task performance. The study also investigated the moderating effect of psychological empowerment for the relationships between perceived stress and behavioral outcomes. The study design was a three-wave self-reported questionnaire. The study sampled 225 full-time employees in South Korea and regression analyses with bootstrapping were conducted to test the moderated mediation models. The bootstrapped 95% CI around the indirect effects did not contain zero; therefore, perceived stress mediated the relationship between workplace ostracism and helping behavior (-.06), voicing behavior (-.07), and task performance (-.07). Further, the moderated mediation analyses found perceived stress mediated the relationships between workplace ostracism and behavioral outcomes only when individuals perceived low levels of psychological empowerment. The findings suggest that workplace ostracism is a stressor and psychological empowerment can mitigate the negative effects of ostracism on behavioral outcomes.

Physical working conditions in young cattle production in Sweden.

PubMed

Bostad, E; Swensson, C; Pinzke, S

2013-01-01

This study investigated physical work environment conditions and sought to identify risk factors in terms of main potential hazards, exposure to physical strain, and the 12-month prevalence of musculoskeletal disorders (MSD) through two postal surveys of Swedish farmers rearing red veal calves (8 to 11 months slaughter age) during April-June 2008 and young bulls (12 to 24 months slaughter age) during March-May 2009. Among 155 red veal producers, the response rate was 45% (n = 59), while among 241 young bull producers finishing 100 or more bulls per year the response rate was 42% (n = 101). A questionnaire was used to obtain general facts about the farm, work time, and frequency of predefined daily and non-daily work tasks. Perceived physical exertion in relation to each work task was assessed by the farmers using the Borg CR-10 scale and further analyzed according to duration and repetitiveness in a physical work strain (PWS) index. The average physical work strain during the predefined work tasks in red veal and young bull finishing was estimated at 3 (moderate strain) on the CR-10 scale. Up to 42% of the surveyed farmers experienced stress and worry about beef production and high levels of potential hazards. High daily work pace and an uncomfortable work climate were other problematic factors. Highly repetitive tasks and physically demanding animal handling were risk factors that increased PWS significantly The 12-month prevalence of MSD was 51% among red veal producers and 65% among young bull producers. Work-related injuries were reported by 20% and 39% of respondents on red veal and young bull farms, respectively, of which 96% and 89% of the cases were related to working with animals.

Does water temperature influence the performance of key survival skills?

PubMed

Schnitzler, C; Button, C; Seifert, L; Armbrust, G; Croft, J L

2018-03-01

Aquatic survival skills may be compromised in cold water thereby increasing the likelihood of drowning. This study compared physiological, psychological, and behavioral responses of humans treading water and swimming in cold and temperate water. Thirty-eight participants were classified as inexperienced (n = 9), recreational (n = 15), or skilled (n = 10) swimmers. They performed 3 tasks: treading water (120 seconds), swim at "comfortable" pace, and swim at "fast" pace in 2 water conditions (28°C vs 10°C). Heart rate, oxygen uptake, psychometric variables, spatio-temporal (swim speed, stroke rate, and stroke length), and coordination type were examined as a function of expertise. Tasks performed in cold water-generated higher cardiorespiratory responses (HR = 145 ± 16 vs 127 ± 21 bpm) and were perceived about 2 points more strenuous on the Borg scale on average (RPE = 14.9 ± 2.8 vs 13.0 ± 2.0). The voluntary durations of both treading water (60 ± 32 vs 91 ± 33 seconds) and swimming at a comfortable pace (66 ± 22 vs 103 ± 34 seconds) were significantly reduced in cold water. However, no systematic changes in movement pattern type could be determined in either the treading water task or the swimming tasks. Water temperature influences the physical demands of these aquatic skills but not necessarily the behavior. Training treading water and swimming skills in temperate water seems to transfer to cold water, but we recommend training these skills in a range of water conditions to help adapt to the initial "cold-shock" response. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

The Effects of Professional Development Activities on Principals' Perceived Instructional Leadership Practices: Multi-Country Data Analysis Using TALIS 2013

ERIC Educational Resources Information Center

Gumus, Emine; Bellibas, Mehmet Sukru

2016-01-01

The purpose of this study was to investigate the extent to which professional development predicts principals' instructional leadership in order to identify whether a relationship exists between the duration of principals' participation in distinct professional development activities and their perceived practice of instructional leadership while…

Automatic generation of efficient orderings of events for scheduling applications

NASA Technical Reports Server (NTRS)

Morris, Robert A.

1994-01-01

In scheduling a set of tasks, it is often not known with certainty how long a given event will take. We call this duration uncertainty. Duration uncertainty is a primary obstacle to the successful completion of a schedule. If a duration of one task is longer than expected, the remaining tasks are delayed. The delay may result in the abandonment of the schedule itself, a phenomenon known as schedule breakage. One response to schedule breakage is on-line, dynamic rescheduling. A more recent alternative is called proactive rescheduling. This method uses statistical data about the durations of events in order to anticipate the locations in the schedule where breakage is likely prior to the execution of the schedule. It generates alternative schedules at such sensitive points, which can be then applied by the scheduler at execution time, without the delay incurred by dynamic rescheduling. This paper proposes a technique for making proactive error management more effective. The technique is based on applying a similarity-based method of clustering to the problem of identifying similar events in a set of events.

Beat-to-beat control of human optokinetic nystagmus slow phase durations

PubMed Central

Furman, Joseph M.

2016-01-01

This study provides the first clear evidence that the generation of optokinetic nystagmus fast phases (FPs) is a decision process that is influenced by performance of a concurrent disjunctive reaction time task (DRT). Ten subjects performed an auditory DRT during constant velocity optokinetic stimulation. Eye movements were measured in three dimensions with a magnetic search coil. Slow phase (SP) durations were defined as the interval between FPs. There were three main findings. Firstly, human optokinetic nystagmus SP durations are consistent with a model of a Gaussian basic interval generator (a type of biological clock), such that FPs can be triggered randomly at the end of a clock cycle (mean duration: 200–250 ms). Kolmogorov-Smirnov tests could not reject the modeled cumulative distribution for any data trials. Secondly, the FP need not be triggered at the end of a clock cycle, so that individual SP durations represent single or multiple clock cycles. Thirdly, the probability of generating a FP at the end of each interval generator cycle decreases significantly during performance of a DRT. These findings indicate that the alternation between SPs and FPs of optokinetic nystagmus is not purely reflexive. Rather, the triggering of the next FP is postponed more frequently if a recently presented DRT trial is pending action when the timing cycle expires. Hence, optokinetic nystagmus FPs show dual-task interference in a manner usually attributed to voluntary movements, including saccades. NEW & NOTEWORTHY This study provides the first clear evidence that the generation of optokinetic nystagmus (OKN) fast phases is a decision process that is influenced by performance of a concurrent disjunctive reaction time task (DRT). The slow phase (SP) durations are consistent with a Gaussian basic interval generator and multiple interval SP durations occur more frequently in the presence of the DRT. Hence, OKN shows dual-task interference in a manner observed in voluntary movements, such as saccades. PMID:27760815

Beat-to-beat control of human optokinetic nystagmus slow phase durations.

PubMed

Balaban, Carey D; Furman, Joseph M

2017-01-01

This study provides the first clear evidence that the generation of optokinetic nystagmus fast phases (FPs) is a decision process that is influenced by performance of a concurrent disjunctive reaction time task (DRT). Ten subjects performed an auditory DRT during constant velocity optokinetic stimulation. Eye movements were measured in three dimensions with a magnetic search coil. Slow phase (SP) durations were defined as the interval between FPs. There were three main findings. Firstly, human optokinetic nystagmus SP durations are consistent with a model of a Gaussian basic interval generator (a type of biological clock), such that FPs can be triggered randomly at the end of a clock cycle (mean duration: 200-250 ms). Kolmogorov-Smirnov tests could not reject the modeled cumulative distribution for any data trials. Secondly, the FP need not be triggered at the end of a clock cycle, so that individual SP durations represent single or multiple clock cycles. Thirdly, the probability of generating a FP at the end of each interval generator cycle decreases significantly during performance of a DRT. These findings indicate that the alternation between SPs and FPs of optokinetic nystagmus is not purely reflexive. Rather, the triggering of the next FP is postponed more frequently if a recently presented DRT trial is pending action when the timing cycle expires. Hence, optokinetic nystagmus FPs show dual-task interference in a manner usually attributed to voluntary movements, including saccades. This study provides the first clear evidence that the generation of optokinetic nystagmus (OKN) fast phases is a decision process that is influenced by performance of a concurrent disjunctive reaction time task (DRT). The slow phase (SP) durations are consistent with a Gaussian basic interval generator and multiple interval SP durations occur more frequently in the presence of the DRT. Hence, OKN shows dual-task interference in a manner observed in voluntary movements, such as saccades. Copyright © 2017 the American Physiological Society.

Icon Duration and Development.

ERIC Educational Resources Information Center

Gummerman, Kent; And Others

In this study, developmental changes in duration of the icon (visual sensory store) were investigated with three converging tachistoscopic tasks. (1) Stimulus interuption detection (SID), a variation of the two-flash threshold method, was performed by 29 first- and 32 fifth-graders, and 32 undergraduates. Icon duration was estimated by stimulus…

The Cumulative Lifting Index (CULI) for the Revised NIOSH Lifting Equation: Quantifying Risk for Workers With Job Rotation.

PubMed

Garg, Arun; Kapellusch, Jay M

2016-08-01

The objectives were to: (a) develop a continuous frequency multiplier (FM) for the Revised NIOSH Lifting Equation (RNLE) as a function of lifting frequency and duration of a lifting task, and (b) describe the Cumulative Lifting Index (CULI), a methodology for estimating physical exposure to workers with job rotation. The existing FM for the RNLE (FME) does not differentiate between task duration >2 hr and <8 hr, which makes quantifying physical exposure to workers with job rotation difficult and presents challenges to job designers. Using the existing FMs for 1, 2, and 8 hr of task durations, we developed a continuous FM (FMP) that extends to 12 hr per day. We simulated 157,500 jobs consisting of two tasks each and, using different combinations of Frequency Independent Lifting Index, lifting frequency and duration of lifting. Biomechanical stresses were estimated using the CULI, time-weighted average (TWA), and peak exposure. The median difference between FME and FMP was ±1% (range: 0%-15%). Compared to CULI, TWA underestimated risk of low-back pain (LBP) for 18% to 30% of jobs, and peak exposure for an assumed 8-hr work shift overestimated risk of LBP for 20% to 25% of jobs. Peak task exposure showed 90% agreement with CULI but ignored one of two tasks. The CULI partially addressed the underestimation of physical exposure using the TWA approach and overestimation of exposure using the peak-exposure approach. The proposed FM and CULI may provide more accurate physical exposure estimates, and therefore estimated risk of LBP, for workers with job rotation. © 2016, Human Factors and Ergonomics Society.

Mental Workload during Brain-Computer Interface Training

PubMed Central

Felton, Elizabeth A.; Williams, Justin C.; Vanderheiden, Gregg C.; Radwin, Robert G.

2012-01-01

It is not well understood how people perceive the difficulty of performing brain-computer interface (BCI) tasks, which specific aspects of mental workload contribute the most, and whether there is a difference in perceived workload between participants who are able-bodied and disabled. This study evaluated mental workload using the NASA Task Load Index (TLX), a multi-dimensional rating procedure with six subscales: Mental Demands, Physical Demands, Temporal Demands, Performance, Effort, and Frustration. Able-bodied and motor disabled participants completed the survey after performing EEG-based BCI Fitts’ law target acquisition and phrase spelling tasks. The NASA-TLX scores were similar for able-bodied and disabled participants. For example, overall workload scores (range 0 – 100) for 1D horizontal tasks were 48.5 (SD = 17.7) and 46.6 (SD 10.3), respectively. The TLX can be used to inform the design of BCIs that will have greater usability by evaluating subjective workload between BCI tasks, participant groups, and control modalities. PMID:22506483

Youth doing dangerous tasks: Supervision matters.

PubMed

Zierold, Kristina M

2017-09-01

Supervisors are partially responsible for ensuring that teens are safe at work. The purpose of this study was to explore whether supervision is related to teens' willingness to do a dangerous task at work. A mixed-methods study consisting of focus groups and a cross-sectional survey was conducted with teens from two public high schools. If asked by a supervisor, 21% of working teens would do a dangerous task. After controlling for gender and age, teens whose supervisor did not establish weekly goals (AOR = 3.54, 95%CI = 1.55-8.08), teens who perceived their supervisors as not approachable (AOR = 2.35, 95%CI = 1.34-4.13), and teens who were not comfortable talking about safety issues (AOR = 1.97, 95%CI = 1.08-3.61) were more likely to do a dangerous task if asked by their supervisors. This study indicates that how teens perceive their supervisor may be associated with whether teens do a dangerous task when asked by their supervisor. © 2017 Wiley Periodicals, Inc.

The effects of motivational climate interventions on psychobiosocial States in high school physical education.

PubMed

Bortoli, Laura; Bertollo, Maurizio; Vitali, Francesca; Filho, Edson; Robazza, Claudio

2015-06-01

The purpose of this study was to examine the effects of task- and ego-involving climate manipulations on students' climate perception and psychobiosocial (PBS) states in a physical education setting. Two subsamples of female students (N = 108, 14-15 years of age) participated in 12 lessons on either a task- or an ego-involving climate intervention as grounded in the TARGET (tasks, authority, recognition, grouping, evaluation, and time) model. At the end of the treatment, the participants of the ego-involved group reported lower scores in the perceived task-involving climate and higher scores in the perceived ego-involving climate compared with their peers in the task-involved group. Lower scores in pleasant/functional PBS states and higher scores in unpleasant/dysfunctional PBS states were also observed in the ego-involved group as a consequence of the intervention. Findings suggested that teachers' induced achievement motivational climates can influence students' perceptions and prompt PBS states consistent with the motivational atmosphere.

Assessing Attention Deficit by Binocular Rivalry.

PubMed

Amador-Campos, Juan Antonio; Aznar-Casanova, J Antonio; Ortiz-Guerra, Juan Jairo; Moreno-Sánchez, Manuel; Medina-Peña, Antonio

2015-12-01

To determine whether the frequency and duration of the periods of suppression of a percept in a binocular rivalry (BR) task can be used to distinguish between participants with ADHD and controls. A total of 122 participants (6-15 years) were assigned to three groups: ADHD-Combined (ADHD-C), ADHD-Predominantly Inattentive (ADHD-I), and controls. They each performed a BR task and two measures were recorded: alternation rate and duration of exclusive dominance periods. ADHD-C group presented fewer alternations and showed greater variability than did the control group; results for the ADHD-I group being intermediate between the two. The duration of dominance periods showed a differential profile: In control group, it remained stable over time, whereas in the clinical groups, it decreased logarithmically as the task progressed. The differences between groups in relation to the BR indicators can be attributed to the activity of involuntary inhibition. © The Author(s) 2013.

Perceived parental beliefs about the causes of success in sport: relationship to athletes' achievement goals and personal beliefs.

PubMed

White, Sally A; Kavussanu, Maria; Tank, Kari M; Wingate, Jason M

2004-02-01

This study examined the relationship between perceived parental beliefs and young athletes' achievement goal orientations and personal beliefs about the causes of success in sport. Participants were 183 male and female athletes, 11-18 years old, involved in team sports. Athletes completed the Task and Ego Orientation in Sport Questionnaire, the Beliefs about the Causes of Sport Success Questionnaire, and two modified versions of the latter inventory to assess their perceptions of their parents' beliefs. Canonical correlation analysis revealed that perceived parental beliefs were related to goal orientations and personal beliefs in a conceptually coherent fashion. Thus, the perceived parental belief that effort leads to success in sport was related to athletes' task orientation and personal belief that effort causes sport success. In contrast, the perceived parental beliefs that superior ability, external factors, and using deceptive tactics are precursors to success in sport corresponded to athletes' ego orientation and the same personal beliefs. The findings are discussed in terms of their implications for understanding the socialization experiences of young athletes.

Inter-Association Task Force Report on Image.

ERIC Educational Resources Information Center

Special Libraries Association, Washington, DC.

In 1988, the Board of Directors of the Special Libraries Association provided funding to a task force to gather data which would determine how certain segments of society perceive librarians, how librarians view themselves and their colleagues, and to provide recommendations for addressing the issue of image. The task force project consisted of…

Self-Efficacy and Interest: Experimental Studies of Optimal Incompetence.

ERIC Educational Resources Information Center

Silvia, Paul J.

2003-01-01

To test the optimal incompetence hypothesis (high self-efficacy lowers task interest), 30 subjects rated interest, perceived difficulty, and confidence of success in different tasks. In study 2, 33 subjects completed a dart-game task in easy, moderate, and difficult conditions. In both, interest was a quadratic function of self-efficacy,…

Text Characteristics of Task Input and Difficulty in Second Language Listening Comprehension

ERIC Educational Resources Information Center

Revesz, Andrea; Brunfaut, Tineke

2013-01-01

This study investigated the effects of a group of task factors on advanced English as a second language learners' actual and perceived listening performance. We examined whether the speed, linguistic complexity, and explicitness of the listening text along with characteristics of the text necessary for task completion influenced comprehension. We…

Logistic Regression Modeling for Predicting Task-Related ICT Use in Teaching

ERIC Educational Resources Information Center

Askar, Petek; Usluel, Yasemin Kocak; Mumcu, Filiz Kuskaya

2006-01-01

The main goal of this study is to estimate the extent to which perceived innovation characteristics are associated with the probability of task related ICT use among secondary school teachers. The tasks were categorized as teaching preparation, teaching delivery, and management. Four hundred and sixteen teachers from secondary schools in Turkey,…

Information-Processing and Perceptions of Control: How Attribution Style Affects Task-Relevant Processing

ERIC Educational Resources Information Center

Yeigh, Tony

2007-01-01

This study investigated the effects of perceived controllability on information processing within Weiner's (1985, 1986) attributional model of learning. Attributional style was used to identify trait patterns of controllability for 37 university students. Task-relevant feedback on an information-processing task was then manipulated to test for…

Effects of signal salience and noise on performance and stress in an abbreviated vigil

NASA Astrophysics Data System (ADS)

Helton, William Stokely

Vigilance or sustained attention tasks traditionally require observers to detect predetermined signals that occur unpredictably over periods of 30 min to several hours (Warm, 1984). These tasks are taxing and have been useful in revealing the effects of stress agents, such as infectious disease and drugs, on human performance (Alluisi, 1969; Damos & Parker, 1994; Warm, 1993). However, their long duration has been an inconvenience. Recently, Temple and his associates (Temple et al., 2000) developed an abbreviated 12-min vigilance task that duplicates many of the findings with longer duration vigils. The present study was designed to explore further the similarity of the abbreviated task to long-duration vigils by investigating the effects of signal salience and jet-aircraft engine noise on performance, operator stress, and coping strategies. Forty-eight observers (24 males and 24 females) were assigned at random to each of four conditions resulting from the factorial combination of signal salience (high and low contrast signals) and background noise (quiet and jet-aircraft noise). As is the case with long-duration vigils (Warm, 1993), signal detection in the abbreviated task was poorer for low salience than for high salience signals. In addition, stress scores, as indexed by the Dundee Stress State Questionnaire (Matthews, Joiner, Gilliland, Campbell, & Falconer, 1999), were elevated in the low as compared to the high salience condition. Unlike longer vigils, however, (Becker, Warm, Dember, & Hancock, 1996), signal detection in the abbreviated task was superior in the presence of aircraft noise than in quiet. Noise also attenuated the stress of the vigil, a result that is counter to previous findings regarding the effects of noise in a variety of other scenarios (Clark, 1984). Examination of observers' coping responses, as assessed by the Coping Inventory for Task Situations (Matthews & Campbell, 1998), indicated that problem-focused coping was the overwhelming coping strategy adopted by observers in the study and that the level of this coping strategy increased in noise. The beneficial effects of jet-aircraft noise for the abbreviated task differentiates it from longer vigilance tasks and suggests that noise may have short-term positive value in vigilance.

The Relationships among Students' Future-Oriented Goals and Subgoals, Perceived Task Instrumentality, and Task-Oriented Self-Regulation Strategies in an Academic Environment

ERIC Educational Resources Information Center

Tabachnick, Sharon E.; Miller, Raymond B.; Relyea, George E.

2008-01-01

The authors performed path analysis, followed by a bootstrap procedure, to test the predictions of a model explaining the relationships among students' distal future goals (both extrinsic and intrinsic), their adoption of a middle-range subgoal, their perceptions of task instrumentality, and their proximal task-oriented self-regulation strategies.…

Does fast or slow evaluation foster greater certainty?

PubMed

Tormala, Zakary L; Clarkson, Joshua J; Henderson, Marlone D

2011-03-01

This research investigates the effect of perceived evaluation duration--that is, the perceived time or speed with which one generates an evaluation--on attitude certainty. Integrating diverse findings from past research, the authors propose that perceiving either fast or slow evaluation can augment attitude certainty depending on specifiable factors. Across three studies, it is shown that when people express opinions, evaluate familiar objects, or typically trust their gut reactions, perceiving fast rather than slow evaluation generally promotes greater certainty. In contrast, when people form opinions, evaluate unfamiliar objects, or typically trust more thoughtful responses, perceiving slow rather than fast evaluation generally promotes greater certainty. Mediation analyses reveal that these effects stem from trade-offs between perceived rational thought and the perceived ease of retrieving an attitude. Implications for research on deliberative versus intuitive decision making are discussed.

Determinants of physical activity in middle-aged woman in Isfahan using the health belief model.

PubMed

Hosseini, Habibollah; Moradi, Razieh; Kazemi, Ashraf; Shahshahani, Maryam Sadat

2017-01-01

Nowadays with respect to the automation of the lifestyle, immobility statistics in middle-aged women has increased and they are at risk for complications of immobility. One of the models used to identify factors associated with physical activity is Health Belief Model utilized in different age and different cultural backgrounds and different results have been obtained from those studies. The purpose of this study was to investigate the factors affecting on physical activity in middle-aged women using Health Belief Model. This descriptive-correlation study was conducted on 224 middle-aged women referring to health centers in Isfahan. Health Belief Model structures including perceived susceptibility and severity, perceived barriers and benefits, and self-efficacy were measured by questionnaire and physical activity was assessed using the international physical activity questionnaire. Collected data were analyzed using descriptive statistics and Pearson correlation coefficient test and regression analysis. There wasn't significant correlation between perceived susceptibility ( P = 0.263, r = 0.075) and perceived severity with physical activity duration ( P = 0.127, r = 0.058) but there was positive and weak correlation between physical activity duration with perceived benefits ( P = 0.001 and r = 0.26) and perceived self-efficacy ( P = 0.001, r = 0.54) and had weak and inverse correlation with perceived barriers ( P = 0.001, r = -0.25). Regression analysis also showed that from among all the Health Belief Model structures just self-efficacy structure has influenced on behavior independently and other structures are affected by it. The obtained results implied on a correlation between benefits, barriers and perceived self-efficacy with and moderate physical activity. Therefore it is necessary to develop appropriate educational programs with emphasis on structures of Health Belief Model that has the maximum impact on physical activity in middle-aged women.

Binocular combination of phase and contrast explained by a gain-control and gain-enhancement model

PubMed Central

Ding, Jian; Klein, Stanley A.; Levi, Dennis M.

2013-01-01

We investigated suprathreshold binocular combination, measuring both the perceived phase and perceived contrast of a cyclopean sine wave. We used a paradigm adapted from Ding and Sperling (2006, 2007) to measure the perceived phase by indicating the apparent location (phase) of the dark trough in the horizontal cyclopean sine wave relative to a black horizontal reference line, and we used the same stimuli to measure perceived contrast by matching the binocular combined contrast to a standard contrast presented to one eye. We found that under normal viewing conditions (high contrast and long stimulus duration), perceived contrast is constant, independent of the interocular contrast ratio and the interocular phase difference, while the perceived phase shifts smoothly from one eye to the other eye depending on the contrast ratios. However, at low contrasts and short stimulus durations, binocular combination is more linear and contrast summation is phase-dependent. To account for phase-dependent contrast summation, we incorporated a fusion remapping mechanism into our model, using disparity energy to shift the monocular phases towards the cyclopean phase in order to align the two eyes' images through motor/sensory fusion. The Ding-Sperling model with motor/sensory fusion mechanism gives a reasonable account of the phase dependence of binocular contrast combination and can account for either the perceived phase or the perceived contrast of a cyclopean sine wave separately; however it requires different model parameters for the two. However, when fit to both phase and contrast data simultaneously, the Ding-Sperling model fails. Incorporating interocular gain enhancement into the model results in a significant improvement in fitting both phase and contrast data simultaneously, successfully accounting for both linear summation at low contrast energy and strong nonlinearity at high contrast energy. PMID:23397038

Prediction of enjoyment in school physical education.

PubMed

Gråstén, Arto; Jaakkola, Timo; Liukkonen, Jarmo; Watt, Anthony; Yli-Piipari, Sami

2012-01-01

The specific aim of this study was to examine whether motivational climate, perceived physical competence, and exercise motivation predict enjoyment in school physical education within the same sample of adolescents across three years of secondary school. A sample of 639 students (girls = 296, boys = 343) aged between 13- to 15-years at the commencement of the study completed the Intrinsic Motivation Climate in Physical Education Questionnaire, Physical Self-Perception Profile, Physical Education Motivation Scale, and Physical Education Enjoyment Scale. Results derived from path analyses indicated that task-involving motivational climate predicted enjoyment in physical education via perceived physical competence and intrinsic motivation in both girls and boys. In particular, these results supported previous findings of Vallerand et. al (1997) with the self-determination theory and the achievement goal theory. Ego-involving climate was not a significant predictor either in girls or boys. The current results provide continuing support for the investigation of Vallerand's model in the physical education setting, and highlight that motivational climate is an area that requires further evaluation as a contributing factor in the improvement of physical education teaching. A better understanding of the role of motivational climate may assist efforts to promote children's and adolescents' perceived physical competence, intrinsic motivation, and enjoyment in the school physical education setting. Key pointsThe findings of the current study support existing suggestions of Vallerand's (1997) model in which social factors mediated by a psychological mediator, and exercise motivation are related to positive consequences in the PE context.Task-involving motivational climate predicted PE enjoyment via perceived physical competence and intrinsic motivation with both girls and boys. Task-involving motivational climate in PE lessons at Grade 7 had a strong association with PE enjoyment via perceived physical competence and intrinsic motivation at Grade 9 for both girls and boys.Ego-involving climate did not fit either the data for the girls or boys, as PE lessons based on ego-involving motivational climate did not significantly influence on the level of PE enjoyment.The results of the current study and previous practical findings support task-involving teaching methods to promote adolescent's PE enjoyment through secondary school years. School PE could be most effective if based on task-involving motivational climate, in which the main objective is increasing students' perceived physical competence, intrinsic motivation, and enjoyment.

Contribution of reactive and proactive control to children's working memory performance: Insight from item recall durations in response sequence planning.

PubMed

Chevalier, Nicolas; James, Tiffany D; Wiebe, Sandra A; Nelson, Jennifer Mize; Espy, Kimberly Andrews

2014-07-01

The present study addressed whether developmental improvement in working memory span task performance relies upon a growing ability to proactively plan response sequences during childhood. Two hundred thirteen children completed a working memory span task in which they used a touchscreen to reproduce orally presented sequences of animal names. Children were assessed longitudinally at 7 time points between 3 and 10 years of age. Twenty-one young adults also completed the same task. Proactive response sequence planning was assessed by comparing recall durations for the 1st item (preparatory interval) and subsequent items. At preschool age, the preparatory interval was generally shorter than subsequent item recall durations, whereas it was systematically longer during elementary school and in adults. Although children mostly approached the task reactively at preschool, they proactively planned response sequences with increasing efficiency from age 7 on, like adults. These findings clarify the nature of the changes in executive control that support working memory performance with age. (PsycINFO Database Record (c) 2014 APA, all rights reserved).

Characterizing visual asymmetries in contrast perception using shaded stimuli.

PubMed

Chacón, José; Castellanos, Miguel Ángel; Serrano-Pedraza, Ignacio

2015-01-01

Previous research has shown a visual asymmetry in shaded stimuli where the perceived contrast depended on the polarity of their dark and light areas (Chacón, 2004). In particular, circles filled out with a top-dark luminance ramp were perceived with higher contrast than top-light ones although both types of stimuli had the same physical contrast. Here, using shaded stimuli, we conducted four experiments in order to find out if the perceived contrast depends on: (a) the contrast level, (b) the type of shading (continuous vs. discrete) and its degree of perceived three-dimensionality, (c) the orientation of the shading, and (d) the sign of the perceived contrast alterations. In all experiments the observers' tasks were to equate the perceived contrast of two sets of elements (usually shaded with opposite luminance polarity), in order to determine the subjective equality point. Results showed that (a) there is a strong difference in perceived contrast between circles filled out with luminance ramp top-dark and top-light that is similar for different contrast levels; (b) we also found asymmetries in contrast perception with different shaded stimuli, and this asymmetry was not related with the perceived three-dimensionality but with the type of shading, being greater for continuous-shading stimuli; (c) differences in perceived contrast varied with stimulus orientation, showing the maximum difference on vertical axis with a left bias consistent with the bias found in previous studies that used visual-search tasks; and (d) asymmetries are consistent with an attenuation in perceived contrast that is selective for top-light vertically-shaded stimuli.

Psychopathological profile and quality of life of patients with oral lichen planus

PubMed Central

Radwan-Oczko, Małgorzata; Zwyrtek, Edyta; Owczarek, Joanna Elżbieta; Szcześniak, Dorota

2018-01-01

Abstract Objectives Oral lichen planus (OLP) is a chronic, multifocal, sometimes painful, inflammatory disease of the oral mucosa. OLP can predispose development of psycho-emotional disorders. Until now, the relationship between the severity of lichen planus and the psychological profile of patients (psychological well-being, perceived stress and pain coping strategies) has never been studied. Material and Methods Study was conducted on 42 OLP patients. Number of sites involved, severity and activity score of OLP were evaluated. Psychological tests were used to evaluate patients’ psycho-emotional condition. The mean duration time of symptomatic OLP was 43 months. Results We detected that the longer the duration of subjective symptoms, the poorer the quality of life and the higher the level of perceived stress (PSS). Also, the higher the PSS results, the greater the anxiety and depression on Hospital Anxiety and Depression Scale (HADS). Likewise, higher level of depression in HADS was strongly correlated with worse quality of life. (p≤0.05). Conclusions In this study, we detected a relationship between duration of the disease, level of perceived stress and quality of life. The longer the disease lasts, the higher it tends to catastrophize. This may influence development or increase of the anxiety and depression and may decrease patients’ quality of life. PMID:29364344

Couples and cancer: feasibility of brief instruction in massage and touch therapy to build caregiver efficacy.

PubMed

Collinge, William; Kahn, Janet; Yarnold, Paul; Bauer-Wu, Susan; McCorkle, Ruth

2007-01-01

This study examined the feasibility of brief instruction in massage and touch therapy for caregivers ("partners") to provide comfort to cancer patients. Fifty partners and 49 patients participated. A longitudinal, within-subjects, repeated measures, control and intervention phases design used self-report instruments to assess feasibility via change in frequency, duration, partner-perceived self-efficacy, and patient-perceived helpfulness over a 90-day follow-up. Exploratory data were collected on psychosocial and quality of life variables. Focus groups provided qualitative data. A structured 6-hour workshop taught basic manual techniques for comfort and relaxation, followed by home practice. Significant increases in frequency (1.2 vs 2.7 times per week) and duration (4.7 vs 12.2 minutes) of massage, both p < .001, were sustained through the 3-month follow-up. Partners' perceived self-efficacy in massage and patients' ratings of its helpfulness more than doubled. Classification tree analysis found caregiver burden, relationship quality, and frequency and duration of practice to predict individual responses. Inhibitions about touch in cancer caregiving may lead to unnecessary physical and emotional distancing at a time when patients need touch the most. Brief instruction may be a feasible intervention to increase caregiver efficacy, patient satisfaction, quality of life, and quality of the relationship.

Optimizing the temporal dynamics of light to human perception.

PubMed

Rieiro, Hector; Martinez-Conde, Susana; Danielson, Andrew P; Pardo-Vazquez, Jose L; Srivastava, Nishit; Macknik, Stephen L

2012-11-27

No previous research has tuned the temporal characteristics of light-emitting devices to enhance brightness perception in human vision, despite the potential for significant power savings. The role of stimulus duration on perceived contrast is unclear, due to contradiction between the models proposed by Bloch and by Broca and Sulzer over 100 years ago. We propose that the discrepancy is accounted for by the observer's "inherent expertise bias," a type of experimental bias in which the observer's life-long experience with interpreting the sensory world overcomes perceptual ambiguities and biases experimental outcomes. By controlling for this and all other known biases, we show that perceived contrast peaks at durations of 50-100 ms, and we conclude that the Broca-Sulzer effect best describes human temporal vision. We also show that the plateau in perceived brightness with stimulus duration, described by Bloch's law, is a previously uncharacterized type of temporal brightness constancy that, like classical constancy effects, serves to enhance object recognition across varied lighting conditions in natural vision-although this is a constancy effect that normalizes perception across temporal modulation conditions. A practical outcome of this study is that tuning light-emitting devices to match the temporal dynamics of the human visual system's temporal response function will result in significant power savings.

Modulation of the composite face effect by unintended emotion cues.

PubMed

Gray, Katie L H; Murphy, Jennifer; Marsh, Jade E; Cook, Richard

2017-04-01

When upper and lower regions from different emotionless faces are aligned to form a facial composite, observers 'fuse' the two halves together, perceptually. The illusory distortion induced by task-irrelevant ('distractor') halves hinders participants' judgements about task-relevant ('target') halves. This composite-face effect reveals a tendency to integrate feature information from disparate regions of intact upright faces, consistent with theories of holistic face processing. However, observers frequently perceive emotion in ostensibly neutral faces, contrary to the intentions of experimenters. This study sought to determine whether this 'perceived emotion' influences the composite-face effect. In our first experiment, we confirmed that the composite effect grows stronger as the strength of distractor emotion increased. Critically, effects of distractor emotion were induced by weak emotion intensities, and were incidental insofar as emotion cues hindered image matching, not emotion labelling per se . In Experiment 2, we found a correlation between the presence of perceived emotion in a set of ostensibly neutral distractor regions sourced from commonly used face databases, and the strength of illusory distortion they induced. In Experiment 3, participants completed a sequential matching composite task in which half of the distractor regions were rated high and low for perceived emotion, respectively. Significantly stronger composite effects were induced by the high-emotion distractor halves. These convergent results suggest that perceived emotion increases the strength of the composite-face effect induced by supposedly emotionless faces. These findings have important implications for the study of holistic face processing in typical and atypical populations.

Cooperative outcome interdependence, task reflexivity, and team effectiveness: a motivated information processing perspective.

PubMed

De Dreu, Carsten K W

2007-05-01

A motivated information processing perspective (C. K. W. De Dreu & P. J. D. Carnevale, 2003; see also V. B. Hinsz, R. S. Tindale, & D. A. Vollrath, 1997) was used to predict that perceived cooperative outcome interdependence interacts with team-level reflexivity to predict information sharing, learning, and team effectiveness. A cross-sectional field study involving management and cross-functional teams (N = 46) performing nonroutine, complex tasks corroborated predictions: The more team members perceived cooperative outcome interdependence, the better they shared information, the more they learned and the more effective they were, especially when task reflexivity was high. When task reflexivity was low, no significant relationship was found between cooperative outcome interdependence and team processes and performance. The author concludes that the motivated information processing perspective is valid outside the confines of the laboratory and can be extended toward teamwork in organizations. 2007 APA, all rights reserved

Driver performance while texting: even a little is too much.

PubMed

McKeever, Joshua D; Schultheis, Maria T; Padmanaban, Vennila; Blasco, Allison

2013-01-01

To examine the impact of text messaging and other in-car behaviors on driving performance under simple and naturalistic road conditions in a driving simulator. Data from 28 healthy individuals (12 female) are presented. Participant age ranged from 18 to 28 (mean = 21.0). Average driving experience was 3.8 years (SD = 2.5). Participants completed a baseline loop condition in which they drove normally through a realistic virtual environment. Next, participants drove an identical loop, and at 3 specified points during this drive, participants were required to (1) complete a radio-tuning task; (2) type and send a text message containing "Drexel University"; and (3) type and send "I am driving to the store." Driving performance and task duration was compared between conditions. Across all tasks, both lane management, F(1,27) = 11.1, P = .002, and velocity, F(1,27) = 10.3, P = .003, varied significantly more while task-engaged. Average lane deviation was significantly greater during a text messaging task than during the baseline drive of the same road segment, t(27) = -2.9, P = .007. Comparison of task durations indicated that both texting tasks took significantly longer to complete than the radio task, with the "Drexel University" text (118 s) taking almost twice as long as the radio-tuning task (60 s). Unexpected and novel findings emerged in the evaluation of duration of texting tasks using the varying text-entry methods, with touch-screen modality taking significantly longer than others. Engaging in secondary tasks while operating a motor vehicle may have deleterious effects on driving performance and increase risk, even under the simplest of driving conditions. Text messaging may constitute a "perfect storm" of risk compared to other in-vehicle tasks such as tuning the car radio. The current investigation demonstrated detrimental effects of text messaging on driving behaviors such as lane maintenance, speed maintenance, and shifts of attention, even under relatively ideal and naturalistic driving conditions (e.g., familiar route, good weather, no traffic).

Predicting workload profiles of brain-robot interface and electromygraphic neurofeedback with cortical resting-state networks: personal trait or task-specific challenge?

NASA Astrophysics Data System (ADS)

Fels, Meike; Bauer, Robert; Gharabaghi, Alireza

2015-08-01

Objective. Novel rehabilitation strategies apply robot-assisted exercises and neurofeedback tasks to facilitate intensive motor training. We aimed to disentangle task-specific and subject-related contributions to the perceived workload of these interventions and the related cortical activation patterns. Approach. We assessed the perceived workload with the NASA Task Load Index in twenty-one subjects who were exposed to two different feedback tasks in a cross-over design: (i) brain-robot interface (BRI) with haptic/proprioceptive feedback of sensorimotor oscillations related to motor imagery, and (ii) control of neuromuscular activity with feedback of the electromyography (EMG) of the same hand. We also used electroencephalography to examine the cortical activation patterns beforehand in resting state and during the training session of each task. Main results. The workload profile of BRI feedback differed from EMG feedback and was particularly characterized by the experience of frustration. The frustration level was highly correlated across tasks, suggesting subject-related relevance of this workload component. Those subjects who were specifically challenged by the respective tasks could be detected by an interhemispheric alpha-band network in resting state before the training and by their sensorimotor theta-band activation pattern during the exercise. Significance. Neurophysiological profiles in resting state and during the exercise may provide task-independent workload markers for monitoring and matching participants’ ability and task difficulty of neurofeedback interventions.

Perceived social justice, long-term unemployment and health. A survey among marginalised groups in Austria.

PubMed

Freidl, Wolfgang; Fazekas, Christian; Raml, Reinhard; Pretis, Manfred; Feistritzer, Gert

2007-07-01

Although socially disadvantaged groups are known to have a high risk of poor health the involved mechanisms and psychosocial dynamics are not fully understood. Long-term unemployment and the perception of social justice may both additionally endanger health. We therefore set out to explore the specific impact of these two context variables on self-reported health, health behaviour, and resources in marginalised groups. A structured interview survey was conducted in three federal provinces in Austria, which targeted a quota sample of 486 subjects in long-term unemployment. Both, duration of long-term unemployment and low perceived social justice, are strongly associated with self-reported poor health and low personal (internal) and social (external) health resources. The best differentiation of dependent variables concerning the univariate analyses was found with respect to social health resources, as all variables on this level significantly correlated with perceived social justice but not with duration of long-term unemployment. While this study does not allow to establish causal relationships, the associations we found suggest that also perceived social justice needs to be taken into account in interventions that are intended to foster equity in health among socially disadvantaged groups.

Prognostic factors for duration of sickness absence due to musculoskeletal disorders.

PubMed

Lötters, Freek; Burdorf, Alex

2006-02-01

The purpose of this prospective cohort study with 1-year follow-up was to determine prognostic factors for duration of sickness absence due to musculoskeletal disorders. Workers were included when on sickness absence of 2 to 6 weeks due to musculoskeletal disorders. A self-administered questionnaire was used to collect personal and work-related factors, pain, functional disability, and general health perceptions. Statistical analysis was done with Cox proportional hazard regression with an interaction variable with time for every risk factor of interest. Univariate and multivariate analyses were performed on musculoskeletal disorders and, separately, for low back pain. The main factors that were associated with longer sickness absence were older age, gender, perceived physical workload, and poorer general health for neck, shoulder and upper extremity disorders, and functional disability, sciatica, worker's own perception of the ability of return to work, and chronic complaints for low back pain. Workers with a high perceived physical work load returned to work increasingly slower over time than expected, whereas workers with a high functional disability returned to work increasingly faster over time. High pain intensity is a major prognostic factor for duration of sickness absence, especially in low back pain. The different disease-specific risk profiles for prolonged sickness absence indicate that low back pain and upper extremity disorders need different approaches when applying intervention strategies with the aim of early return to work. The interaction of perceived physical workload with time suggests that perceived physical workload would increasingly hamper return to work and, hence, supports the need for workplace interventions among workers off work for prolonged periods.

Cognitive Abilities Explaining Age-Related Changes in Time Perception of Short and Long Durations

ERIC Educational Resources Information Center

Zelanti, Pierre S.; Droit-Volet, Sylvie

2011-01-01

The current study investigated how the development of cognitive abilities explains the age-related changes in temporal judgment over short and long duration ranges from 0.5 to 30 s. Children (5- and 9-year-olds) as well as adults were given a temporal bisection task with four different duration ranges: a duration range shorter than 1 s, two…

Cognitive Performance and Heart Rate Variability: The Influence of Fitness Level

PubMed Central

Luque-Casado, Antonio; Zabala, Mikel; Morales, Esther; Mateo-March, Manuel; Sanabria, Daniel

2013-01-01

In the present study, we investigated the relation between cognitive performance and heart rate variability as a function of fitness level. We measured the effect of three cognitive tasks (the psychomotor vigilance task, a temporal orienting task, and a duration discrimination task) on the heart rate variability of two groups of participants: a high-fit group and a low-fit group. Two major novel findings emerged from this study. First, the lowest values of heart rate variability were found during performance of the duration discrimination task, compared to the other two tasks. Second, the results showed a decrement in heart rate variability as a function of the time on task, although only in the low-fit group. Moreover, the high-fit group showed overall faster reaction times than the low-fit group in the psychomotor vigilance task, while there were not significant differences in performance between the two groups of participants in the other two cognitive tasks. In sum, our results highlighted the influence of cognitive processing on heart rate variability. Importantly, both behavioral and physiological results suggested that the main benefit obtained as a result of fitness level appeared to be associated with processes involving sustained attention. PMID:23437276

The effect of music on 10-km cycle time-trial performance.

PubMed

Hagen, Jana; Foster, Carl; Rodríguez-Marroyo, Jose; de Koning, Jos J; Mikat, Richard P; Hendrix, Charles R; Porcari, John P

2013-01-01

Music is widely used as an ergogenic aid in sport, but there is little evidence of its effectiveness during closed-loop athletic events. In order to determine the effectiveness of music as an ergogenic aid, well-trained and task-habituated cyclists performed 10-km cycle time trials either while listening to self-selected motivational music or with auditory input blocked. There were no statistically significant differences in performance time or physiological or psychological markers related to music (time-trial duration17.75 ± 2.10 vs 17.81 ± 2.06 min, mean power output 222 ± 66 vs 220 ± 65 W, peak heart rate184 ± 9 vs 183 ± 8 beats/min, peak blood lactate12.1 ± 2.6 vs 11.9 ± 2.1 mmol/L, and final rating of perceived exertion 8.4 ± 1.5 vs 8.5 ± 1.6). It is concluded that during exercise at competitive intensity, there is no meaningful effect of music on either performance or physiology.

Repeat work bouts increase thermal strain for Australian firefighters working in the heat.

PubMed

Walker, Anthony; Argus, Christos; Driller, Matthew; Rattray, Ben

2015-01-01

Firefighters regularly re-enter fire scenes during long duration emergency events with limited rest between work bouts. It is unclear whether this practice is impacting on the safety of firefighters. To evaluate the effects of multiple work bouts on firefighter physiology, strength, and cognitive performance when working in the heat. Seventy-seven urban firefighters completed two 20-minute simulated search and rescue tasks in a heat chamber (105 ± 5°C), separated by a 10-minute passive recovery. Core and skin temperature, rate of perceived exertion (RPE), thermal sensation (TS), grip strength, and cognitive changes between simulations were evaluated. Significant increases in core temperature and perceptual responses along with declines in strength were observed following the second simulation. No differences for other measures were observed. A significant increase in thermal strain was observed when firefighters re-entered a hot working environment. We recommend that longer recovery periods or active cooling methods be employed prior to re-entry.

Visual preference for isochronic movement does not necessarily emerge from movement kinematics: a challenge for the motor simulation theory.

PubMed

Bidet-Ildei, Christel; Méary, David; Orliaguet, Jean-Pierre

2008-01-17

The aim of this experiment was to show that the visual preference for isochronic movements does not necessarily imply a motor simulation and therefore, does not depend on the kinematics of the perceived movement. To demonstrate this point, the participants' task was to adjust the velocity (the period) of a dot that depicted an elliptic motion with different perimeters (from 3 to 60 cm). The velocity profile of the movement conformed ("natural motions") or not ("unnatural motions") to the law of co-variation velocity-curvature (two-thirds power law), which is usually observed in the production of elliptic movements. For each condition, we evaluated the isochrony principle, i.e., the tendency to prefer constant durations of movement irrespective to changes in the trajectory perimeter. Our findings indicate that isochrony principle was observed whatever the kinematics of the movement (natural or unnatural). Therefore, they suggest that the perceptive preference for isochronic movements does not systematically imply a motor simulation.

Repeat work bouts increase thermal strain for Australian firefighters working in the heat

PubMed Central

Walker, Anthony; Argus, Christos; Driller, Matthew; Rattray, Ben

2015-01-01

Background: Firefighters regularly re-enter fire scenes during long duration emergency events with limited rest between work bouts. It is unclear whether this practice is impacting on the safety of firefighters. Objectives:To evaluate the effects of multiple work bouts on firefighter physiology, strength, and cognitive performance when working in the heat. Methods: Seventy-seven urban firefighters completed two 20-minute simulated search and rescue tasks in a heat chamber (105 ± 5°C), separated by a 10-minute passive recovery. Core and skin temperature, rate of perceived exertion (RPE), thermal sensation (TS), grip strength, and cognitive changes between simulations were evaluated. Results: Significant increases in core temperature and perceptual responses along with declines in strength were observed following the second simulation. No differences for other measures were observed. Conclusions: A significant increase in thermal strain was observed when firefighters re-entered a hot working environment. We recommend that longer recovery periods or active cooling methods be employed prior to re-entry. PMID:25849044

Exercise tolerance during VO2max testing is a multifactorial psychobiological phenomenon.

PubMed

Midgley, Adrian W; Earle, Keith; McNaughton, Lars R; Siegler, Jason C; Clough, Peter; Earle, Fiona

2017-01-01

Fifty-nine men completed a VO 2max test and a questionnaire to establish reasons for test termination, perceived exercise reserve (difference between actual test duration and the duration the individual perceived could have been achieved if continued until physical limitation), and perception of verbal encouragement. Participants gave between 1 and 11 factors as reasons for test termination, including leg fatigue, various perceptions of physical discomfort, safety concerns, and achievement of spontaneously set goals. The two most common main reasons were leg fatigue and breathing discomfort, which were predicted by pre-to-post test changes in pulmonary function (p = 0.038) and explosive leg strength (p = 0.042; R 2  = 0.40). Median (interquartile range) perceived exercise reserve, was 45 (50) s. Two-thirds of participants viewed verbal encouragement positively, whereas one-third had a neutral or negative perception. This study highlights the complexity of exercise tolerance during VO 2max testing and more research should explore these novel findings.

Aging road user studies of intersection safety.

DOT National Transportation Integrated Search

2014-10-01

Task 1.1 assessed younger (21-35 years), middle-aged (50-64 years), and older (65+) drivers ability to : quickly perceive the presence of marked/unmarked crosswalks and pedestrians within them in computer-based : laboratory tasks that recorded res...

Face recognition in age related macular degeneration: perceived disability, measured disability, and performance with a bioptic device.

PubMed

Tejeria, L; Harper, R A; Artes, P H; Dickinson, C M

2002-09-01

(1) To explore the relation between performance on tasks of familiar face recognition (FFR) and face expression difference discrimination (FED) with both perceived disability in face recognition and clinical measures of visual function in subjects with age related macular degeneration (AMD). (2) To quantify the gain in performance for face recognition tasks when subjects use a bioptic telescopic low vision device. 30 subjects with AMD (age range 66-90 years; visual acuity 0.4-1.4 logMAR) were recruited for the study. Perceived (self rated) disability in face recognition was assessed by an eight item questionnaire covering a range of issues relating to face recognition. Visual functions measured were distance visual acuity (ETDRS logMAR charts), continuous text reading acuity (MNRead charts), contrast sensitivity (Pelli-Robson chart), and colour vision (large panel D-15). In the FFR task, images of famous people had to be identified. FED was assessed by a forced choice test where subjects had to decide which one of four images showed a different facial expression. These tasks were repeated with subjects using a bioptic device. Overall perceived disability in face recognition did not correlate with performance on either task, although a specific item on difficulty recognising familiar faces did correlate with FFR (r = 0.49, p<0.05). FFR performance was most closely related to distance acuity (r = -0.69, p<0.001), while FED performance was most closely related to continuous text reading acuity (r = -0.79, p<0.001). In multiple regression, neither contrast sensitivity nor colour vision significantly increased the explained variance. When using a bioptic telescope, FFR performance improved in 86% of subjects (median gain = 49%; p<0.001), while FED performance increased in 79% of subjects (median gain = 50%; p<0.01). Distance and reading visual acuity are closely associated with measured task performance in FFR and FED. A bioptic low vision device can offer a significant improvement in performance for face recognition tasks, and may be useful in reducing the handicap associated with this disability. There is, however, little evidence for a correlation between self rated difficulty in face recognition and measured performance for either task. Further work is needed to explore the complex relation between the perception of disability and measured performance.

Face recognition in age related macular degeneration: perceived disability, measured disability, and performance with a bioptic device

PubMed Central

Tejeria, L; Harper, R A; Artes, P H; Dickinson, C M

2002-01-01

Aims: (1) To explore the relation between performance on tasks of familiar face recognition (FFR) and face expression difference discrimination (FED) with both perceived disability in face recognition and clinical measures of visual function in subjects with age related macular degeneration (AMD). (2) To quantify the gain in performance for face recognition tasks when subjects use a bioptic telescopic low vision device. Methods: 30 subjects with AMD (age range 66–90 years; visual acuity 0.4–1.4 logMAR) were recruited for the study. Perceived (self rated) disability in face recognition was assessed by an eight item questionnaire covering a range of issues relating to face recognition. Visual functions measured were distance visual acuity (ETDRS logMAR charts), continuous text reading acuity (MNRead charts), contrast sensitivity (Pelli-Robson chart), and colour vision (large panel D-15). In the FFR task, images of famous people had to be identified. FED was assessed by a forced choice test where subjects had to decide which one of four images showed a different facial expression. These tasks were repeated with subjects using a bioptic device. Results: Overall perceived disability in face recognition did not correlate with performance on either task, although a specific item on difficulty recognising familiar faces did correlate with FFR (r = 0.49, p<0.05). FFR performance was most closely related to distance acuity (r = −0.69, p<0.001), while FED performance was most closely related to continuous text reading acuity (r = −0.79, p<0.001). In multiple regression, neither contrast sensitivity nor colour vision significantly increased the explained variance. When using a bioptic telescope, FFR performance improved in 86% of subjects (median gain = 49%; p<0.001), while FED performance increased in 79% of subjects (median gain = 50%; p<0.01). Conclusion: Distance and reading visual acuity are closely associated with measured task performance in FFR and FED. A bioptic low vision device can offer a significant improvement in performance for face recognition tasks, and may be useful in reducing the handicap associated with this disability. There is, however, little evidence for a correlation between self rated difficulty in face recognition and measured performance for either task. Further work is needed to explore the complex relation between the perception of disability and measured performance. PMID:12185131

Professional or administrative value patterns? Clinical pathways in medical problem-solving processes.

PubMed

Holmberg, Leif

2007-11-01

A health-care organization simultaneously belongs to two different institutional value patterns: a professional and an administrative value pattern. At the administrative level, medical problem-solving processes are generally perceived as the efficient application of familiar chains of activities to well-defined problems; and a low task uncertainty is therefore assumed at the work-floor level. This assumption is further reinforced through clinical pathways and other administrative guidelines. However, studies have shown that in clinical practice such administrative guidelines are often considered inadequate and difficult to implement mainly because physicians generally perceive task uncertainty to be high and that the guidelines do not cover the scope of encountered deviations. The current administrative level guidelines impose uniform structural features that meet the requirement for low task uncertainty. Within these structural constraints, physicians must organize medical problem-solving processes to meet any task uncertainty that may be encountered. Medical problem-solving processes with low task uncertainty need to be organized independently of processes with high task uncertainty. Each process must be evaluated according to different performance standards and needs to have autonomous administrative guideline models. Although clinical pathways seem appropriate when there is low task uncertainty, other kinds of guidelines are required when the task uncertainty is high.

Validation of inertial measurement units with an optoelectronic system for whole-body motion analysis.

PubMed

Robert-Lachaine, Xavier; Mecheri, Hakim; Larue, Christian; Plamondon, André

2017-04-01

The potential of inertial measurement units (IMUs) for ergonomics applications appears promising. However, previous IMUs validation studies have been incomplete regarding aspects of joints analysed, complexity of movements and duration of trials. The objective was to determine the technological error and biomechanical model differences between IMUs and an optoelectronic system and evaluate the effect of task complexity and duration. Whole-body kinematics from 12 participants was recorded simultaneously with a full-body Xsens system where an Optotrak cluster was fixed on every IMU. Short functional movements and long manual material handling tasks were performed and joint angles were compared between the two systems. The differences attributed to the biomechanical model showed significantly greater (P ≤ .001) RMSE than the technological error. RMSE was systematically higher (P ≤ .001) for the long complex task with a mean on all joints of 2.8° compared to 1.2° during short functional movements. Definition of local coordinate systems based on anatomical landmarks or single posture was the most influent difference between the two systems. Additionally, IMUs accuracy was affected by the complexity and duration of the tasks. Nevertheless, technological error remained under 5° RMSE during handling tasks, which shows potential to track workers during their daily labour.

Acceptance and perceived usefulness of robots to assist with activities of daily living and healthcare tasks.

PubMed

Hall, Amanda K; Backonja, Uba; Painter, Ian; Cakmak, Maya; Sung, Minjung; Lau, Timothy; Thompson, Hilaire J; Demiris, George

2017-11-29

As the number of older adults living with chronic conditions continues to rise, they will require assistance with activities of daily living (ADL) and healthcare tasks to continue living independently in their homes. One proposed solution to assist with the care needs of an aging population and a shrinking healthcare workforce is robotic technology. Using a cross-sectional survey design, we purposively sampled adults (≥18 years old) to assess generational acceptance and perceived usefulness of robots to assist with ADLs, healthcare tasks, and evaluate acceptance of robotic healthcare assistance across different settings. A total of 499 adults (age range [years] 18-98, Mean = 38.7, SD = 22.7) responded to the survey. Significant differences were found among young, middle-aged, and older adults on perceived usefulness of robots for cleaning, escorting them around town, acting as companionship, delivering meals, assessing sadness and calling for help, providing medical advice, taking vital sign assessments, and assisting with personal care (p < 0.05). The majority of younger adults reported that they would like a robot to provide healthcare assistance in the hospital, compared to middle-aged and older adults (p < 0.001). Results of this study can guide the design of robots to assist adults of all ages with useful tasks.

Vocal Ergonomics in the Workplace: Heating, Ventilation, and Air-Conditioning Method Influences on Vocal Comfort and Function.

PubMed

Sandage, Mary J; Rahn, Keith A; Smith, Audrey G

2017-02-01

The purpose of this study was to examine the influence of the heating, ventilation, and air-conditioning method on voice function following a voicing task using ecologically valid offices, one with radiant HVAC and one with forced air. A total of 12 consented participants (6 women, 6 men) narrated a video in each of 4 environmental conditions in a within-between repeated-measures design. Acoustic data were collected with an ambulatory phonation monitor and perceived phonatory effort was determined following the voicing task. Data were analyzed using a within-between repeated-measures analysis of variance with significance set at α < .05. Perceived phonatory effort did not differ between environments; however, a significant difference in vocal amplitude between 2 trials was identified for the male participants and physiologically significant differences in vocal amplitude were identified for male and female participants. The findings suggest that perceived phonatory effort may not be a sensitive measure of vocal function differences following a voicing task in ecologically valid office spaces despite significant acoustic findings. Future research should address longer exposure to environmental differences combined with a longer voicing task within ecologically valid work spaces as well as the recruitment of participants who have particular vulnerability to environmental perturbations.

Time perception deficit in children with ADHD.

PubMed

Yang, Binrang; Chan, Raymond C K; Zou, Xiaobing; Jing, Jin; Mai, Jianning; Li, Jing

2007-09-19

Time perception deficit has been demonstrated in children with attention deficit hyperactivity disorder (ADHD) by using time production and time reproduction tasks. The impact of motor demand, however, has not yet been fully examined. The current study, which is reported herein, aimed to investigate the pure time perception of Chinese children with ADHD by using a duration discrimination task. A battery of tests that were specifically designed to measure time perception and other related abilities, such as inhibition, attention, and working memory, was administered to 40 children with ADHD and to 40 demographically matched healthy children. A repeated measure MANOVA indicated that children with ADHD showed significantly higher discrimination thresholds than did healthy controls, and there was an interaction effect between group and duration. Pairwise comparison indicated that children with ADHD were less accurate in discriminating duration at either target duration. Working memory (Corsi blocks task) was related to the discrimination threshold at a duration of 800 ms after controlling for full-scale IQ (FIQ) in the ADHD group, but this did not survive the Bonferroni correction. The results indicated that children with ADHD may have perceptual deficits in time discrimination. They needed a greater difference between the comparison and target intervals to discriminate the short, median, and long durations reliably. This study provides further support for the existence of a generic time perception deficit, which is probably due to the involvement of a dysfunctional fronto-striato-cerebellar network in this capacity, especially the presence of deficits in basic internal timing mechanisms.

Interaction between Task Values and Self-Efficacy on Maladaptive Achievement Strategy Use

ERIC Educational Resources Information Center

Lee, Jeesoo; Bong, Mimi; Kim, Sung-il

2014-01-01

We tested the interaction between task value and self-efficacy on defensive pessimism, academic cheating, procrastination and self-handicapping among 574 Korean 11th graders in the context of English as a foreign language. We hypothesised that perceiving high value in tasks or domains for which self-efficacy was low would pose a threat to…

Biomechanical evaluation of nursing tasks in a hospital setting.

PubMed

Jang, R; Karwowski, W; Quesada, P M; Rodrick, D; Sherehiy, B; Cronin, S N; Layer, J K

2007-11-01

A field study was conducted to investigate spinal kinematics and loading in the nursing profession using objective and subjective measurements of selected nursing tasks observed in a hospital setting. Spinal loading was estimated using trunk motion dynamics measured by the lumbar motion monitor (LMM) and lower back compressive and shear forces were estimated using the three-dimensional (3D) Static Strength Prediction Program. Subjective measures included the rate of perceived physical effort and the perceived risk of low back pain. A multiple logistic regression model, reported in the literature for predicting low back injury based on defined risk groups, was tested. The study results concluded that the major risk factors for low back injury in nurses were the weight of patients handled, trunk moment, and trunk axial rotation. The activities that required long time exposure to awkward postures were perceived by nurses as a high physical effort. This study also concluded that self-reported perceived exertion could be used as a tool to identify nursing activities with a high risk of low-back injury.

[Differential aspects of subjective burden of tinnitus aurium].

PubMed

Perrig-Chiello, P; Gusset, S

1996-01-01

This study focuses on psychological variables, which could influence the subjectively perceived strain of tinnitus. They concern personality traits such as self-attentiveness, control beliefs and different dimensions of psychological health. Two groups of tinnitus patients were compared, one with low subjectively perceived strain (n = 20), the other with high subjectively perceived strain (n = 30). Results reveal that people with high subjectively perceived strain do not only perceive their tinnitus more often, but they are more self-centered and report significantly more general somatic complaints than people with low subjectively perceived strain. They obviously pay more attention to themselves and as a consequence also to their tinnitus. However, we didn't find any relationship between control beliefs and subjectively perceived tinnitus strain. Furthermore, duration of the noises, their loudness, their localisation and the knowledge of the cause of tinnitus also seem to affect the perception of the noises.

Respiratory poliomyelitis: a follow-up study.

PubMed Central

Alcock, A J; Hildes, J A; Kaufert, P A; Kaufert, J M; Bickford, J

1984-01-01

Data from the medical records of 113 patients living in Manitoba who had contracted respiratory poliomyelitis between 1952 and 1959 were compared with information obtained from interviews with these patients in 1980. The study was designed to determine whether the patients' respiratory function, mobility, ability to perform daily tasks, and employment, residential and marital status had changed between 1 year after the onset of polio and 1980. The patients' dependence on mechanical aids and other people was also studied. More than half (56%) of the patients perceived their respiratory impairment to be the same as it was 1 year after the onset of polio, 27% perceived the impairment to be increased, and 17% perceived it to be decreased. There was an association between level of respiratory function, mobility and ability to perform daily tasks. The 69 patients who lived at home had better respiratory function, mobility and ability to perform daily tasks than the 24 patients who were assisted by a home care program and the 20 who lived in hospital. The latter group had the lowest levels of respiratory and functional ability. PMID:6586273

Influence of warm-up duration on physical performance and psychological perceptions in handball players.

PubMed

Romaratezabala, Estibaliz; Nakamura, Fábio Yuzo; Castillo, Daniel; Gorostegi-Anduaga, Ilargi; Yanci, Javier

2018-01-01

The purpose of the study was to analyse the effect of two warm-up protocols of different duration on physical performance, perceived load and perception of being ready for a match in handball players. Eighteen handball players were randomly divided into two groups (Wup 34min , warm-up protocol of 34 min, Wup 17min , warm-up protocol of 17 min). Before and after the warm-up protocols, they performed a battery of physical tests and recorded their perception of feeling ready for a match. At the end of the warm-up protocols, all the players evaluated their differentiated perceived effort (dRPE). The results showed that neither of the protocols significantly modified (p > 0.05) the players' physical performance. However, the Wup 34min group showed higher values in the differentiated warm-up perceived load (dRPE-WL) (p < 0.01, TE = 0.97-1.27, high) than the Wup 17min group. The players with a greater perceived muscular load (RPE MUSC ) experienced a greater decrease in their acceleration capacity (r = 0.48-0.49, p < 0.05). In spite of the fact that neither of the warm-up protocols significantly modified the players' physical performance, a greater perceived muscular load may cause a greater decrease in acceleration capacity.

Resilience and well-being amongst seafarers: cross-sectional study of crew across 51 ships.

PubMed

Doyle, Niamh; MacLachlan, Malcolm; Fraser, Alistair; Stilz, Ralf; Lismont, Karlien; Cox, Henriette; McVeigh, Joanne

2016-02-01

Duration at sea was investigated as a potential chronic stressor amongst seafarers in addition to the mediating roles of previous seafaring experience and hardiness between duration and stress. In a cross-sectional design, questionnaires were emailed to 53 tanker vessels in an international shipping company with questions relating to duration at sea, perceived stress, personality hardiness and work characteristics. The sample comprised 387 seafarers (98% male) including ratings, crew, officers, engineers, and catering staff that had been on board their ship between 0 and 24 weeks. Duration at sea was unrelated to self-reported perceived stress, even after controlling for previous seafaring experience and hardiness. Additional regression analyses demonstrated that self-reported higher levels of resilience, longer seafaring experience and greater instrumental work support were significantly associated with lower levels of self-reported stress at sea. These results imply that at least for the first 24 weeks at sea, exposure to the seafaring environment did not act as a chronic stressor. The confined environment of a ship presents particular opportunities to introduce resilience and work support programmes to help seafarers manage and reduce stress, and to enhance their well-being at sea.

The time to remember: Temporal compression and duration judgements in memory for real-life events.

PubMed

Jeunehomme, Olivier; D'Argembeau, Arnaud

2018-05-01

Recent studies suggest that the continuous flow of information that constitutes daily life events is temporally compressed in episodic memory, yet the characteristics and determinants of this compression mechanism remain unclear. This study examined this question using an experimental paradigm incorporating wearable camera technology. Participants experienced a series of real-life events and were later asked to mentally replay various event sequences that were cued by pictures taken during the original events. Estimates of temporal compression (the ratio of the time needed to mentally re-experience an event to the actual event duration) showed that events were replayed, on average, about eight times faster than the original experiences. This compression mechanism seemed to operate by representing events as a succession of moments or slices of prior experience separated by temporal discontinuities. Importantly, however, rates of temporal compression were not constant and were lower for events involving goal-directed actions. The results also showed that the perceived duration of events increased with the density of recalled moments of prior experience. Taken together, these data extend our understanding of the mechanisms underlying the temporal compression and perceived duration of real-life events in episodic memory.

Oral and Hand Movement Speeds are Associated with Expressive Language Ability in Children with Speech Sound Disorder

PubMed Central

Peter, Beate

2013-01-01

This study tested the hypothesis that children with speech sound disorder have generalized slowed motor speeds. It evaluated associations among oral and hand motor speeds and measures of speech (articulation and phonology) and language (receptive vocabulary, sentence comprehension, sentence imitation), in 11 children with moderate to severe SSD and 11 controls. Syllable durations from a syllable repetition task served as an estimate of maximal oral movement speed. In two imitation tasks, nonwords and clapped rhythms, unstressed vowel durations and quarter-note clap intervals served as estimates of oral and hand movement speed, respectively. Syllable durations were significantly correlated with vowel durations and hand clap intervals. Sentence imitation was correlated with all three timed movement measures. Clustering on syllable repetition durations produced three clusters that also differed in sentence imitation scores. Results are consistent with limited movement speeds across motor systems and SSD subtypes defined by motor speeds as a corollary of expressive language abilities. PMID:22411590

Oral and hand movement speeds are associated with expressive language ability in children with speech sound disorder.

PubMed

Peter, Beate

2012-12-01

This study tested the hypothesis that children with speech sound disorder have generalized slowed motor speeds. It evaluated associations among oral and hand motor speeds and measures of speech (articulation and phonology) and language (receptive vocabulary, sentence comprehension, sentence imitation), in 11 children with moderate to severe SSD and 11 controls. Syllable durations from a syllable repetition task served as an estimate of maximal oral movement speed. In two imitation tasks, nonwords and clapped rhythms, unstressed vowel durations and quarter-note clap intervals served as estimates of oral and hand movement speed, respectively. Syllable durations were significantly correlated with vowel durations and hand clap intervals. Sentence imitation was correlated with all three timed movement measures. Clustering on syllable repetition durations produced three clusters that also differed in sentence imitation scores. Results are consistent with limited movement speeds across motor systems and SSD subtypes defined by motor speeds as a corollary of expressive language abilities.

Adding sleep restriction to the equation: impact on wildland firefighters' work performance and physiology in hot conditions.

PubMed

Vincent, Grace E; Ferguson, Sally; Larsen, Brianna; Ridgers, Nicola D; Snow, Rod; Aisbett, Brad

2018-04-06

To examine the effects of sleep restriction on firefighters' physical task performance, physical activity, and physiological and perceived exertion during simulated hot wildfire conditions. 31 firefighters were randomly allocated to either the hot (n = 18, HOT; 33 °C, 8-h sleep opportunity) or hot and sleep restricted (n = 13, HOT + SR; 33 °C, 4-h sleep opportunity) condition. Intermittent, self-paced work circuits of six firefighting tasks were performed for 3 days. Firefighters self-reported ratings of perceived exertion. Heart rate, core temperature, and physical activity were measured continuously. Fluids were consumed ad libitum, and all food and fluids consumed were recorded. Urine volume and urine specific gravity (USG) were analysed and sleep was assessed using polysomnography (PSG). There were no differences between the HOT and HOT + SR groups in firefighters' physical task performance, heart rate, core temperature, USG, or fluid intake. Ratings of perceived exertion were higher (p < 0.05) in the HOT + SR group for two of the six firefighting tasks. The HOT group spent approximately 7 min more undertaking moderate physical activity throughout the 2-h work circuits compared to the HOT + SR group. Two nights of sleep restriction did not influence firefighters' physical task performance or physiological responses during 3 days of simulated wildfire suppression. Further research is needed to explore firefighters' pacing strategies during real wildfire suppression.

Motivational climate, staff and members' behaviors, and members' psychological well-being at a national fitness franchise.

PubMed

Brown, Theresa C; Fry, Mary D

2014-06-01

The purpose of this study was to examine the association between members' perceptions of staffs behaviors, motivational climate, their own behaviors, commitment to future exercise, and life satisfaction in a group-fitness setting. The theory-driven hypothesized mediating role of perceptions of the climate was also tested. Members (N = 5,541) of a national group-fitness studio franchise completed a survey regarding their class experiences. The survey included questions that measured participants' perceptions of the motivational climate (caring, task-involving, ego-involving), perceptions of staff's behaviors, their own behaviors, commitment to exercise, and life satisfaction. Structural equation modeling was used to assess both the association between variables and the theoretically driven predictive relationships. The participants perceived the environment as highly caring and task-involving and low ego-involving. They reported high exercise commitment and moderately high life satisfaction and perceived that the staffs and their own behaviors reflected caring, task-involving characteristics. Structural equation modeling demonstrated that those who perceived a higher caring, task-involving climate and lower ego-involving climate were more likely to report more task-involving, caring behaviors among the staff and themselves as well as greater commitment to exercise. In addition, a theory-driven mediational model suggested that staff behaviors may be an antecedent to members' exercise experiences by impacting their perceptions of the climate. The results of this study give direction to specific behaviors in which staff of group-fitness programs might engage to positively influence members' exercise experiences.

Detecting deviations from metronomic timing in music: effects of perceptual structure on the mental timekeeper.

PubMed

Repp, B H

1999-04-01

The detectability of a deviation from metronomic timing--of a small local increment in interonset interval (IOI) duration--in a musical excerpt is subject to positional biases, or "timing expectations," that are closely related to the expressive timing (sequence of IOI durations) typically produced by musicians in performance (Repp, 1992b, 1998c, 1998d). Experiment 1 replicated this finding with some changes in procedure and showed that the perception-performance correlation is not the result of formal musical training or availability of a musical score. Experiments 2 and 3 used a synchronization task to examine the hypothesis that participants' perceptual timing expectations are due to systematic modulations in the period of a mental timekeeper that also controls perceptual-motor coordination. Indeed, there was systematic variation in the asynchronies between taps and metronomically timed musical event onsets, and this variation was correlated both with the variations in IOI increment detectability (Experiment 1) and with the typical expressive timing pattern in performance. When the music contained local IOI increments (Experiment 2), they were almost perfectly compensated for on the next tap, regardless of their detectability in Experiment 1, which suggests a perceptual-motor feedback mechanism that is sensitive to subthreshold timing deviations. Overall, the results suggest that aspects of perceived musical structure influence the predictions of mental timekeeping mechanisms, thereby creating a subliminal warping of experienced time.

An exploratory study of long-haul truck drivers' secondary tasks and reasons for performing them.

PubMed

Iseland, Tobias; Johansson, Emma; Skoog, Siri; Dåderman, Anna M

2018-08-01

Research on drivers has shown how certain visual-manual secondary tasks, unrelated to driving, increase the risk of being involved in crashes. The purpose of the study was to investigate (1) if long-haul truck drivers in Sweden engage in secondary tasks while driving, what tasks are performed and how frequently, (2) the drivers' self-perceived reason/s for performing them, and (3) if psychological factors might reveal reasons for their engaging in secondary tasks. The study comprised 13 long-haul truck drivers and was conducted through observations, interviews, and questionnaires. The drivers performed secondary tasks, such as work environment related "necessities" (e.g., getting food and/or beverages from the refrigerator/bag, eating, drinking, removing a jacket, face rubbing, and adjusting the seat), interacting with a mobile phone/in-truck technology, and doing administrative tasks. The long-haul truck drivers feel bored and use secondary tasks as a coping strategy to alleviate boredom/drowsiness, and for social interaction. The higher number of performed secondary tasks could be explained by lower age, shorter driver experience, less openness to experience, lower honesty-humility, lower perceived stress, lower workload, and by higher health-related quality of life. These explanatory results may serve as a starting point for further studies on large samples to develop a safer and healthier environment for long-haul truck drivers. Copyright © 2018. Published by Elsevier Ltd.

Characterizing “fibrofog”: Subjective appraisal, objective performance, and task-related brain activity during a working memory task

PubMed Central

Walitt, Brian; Čeko, Marta; Khatiwada, Manish; Gracely, John L.; Rayhan, Rakib; VanMeter, John W.; Gracely, Richard H.

2016-01-01

The subjective experience of cognitive dysfunction (“fibrofog”) is common in fibromyalgia. This study investigated the relation between subjective appraisal of cognitive function, objective cognitive task performance, and brain activity during a cognitive task using functional magnetic resonance imaging (fMRI). Sixteen fibromyalgia patients and 13 healthy pain-free controls completed a battery of questionnaires, including the Multiple Ability Self-Report Questionnaire (MASQ), a measure of self-perceived cognitive difficulties. Participants were evaluated for working memory performance using a modified N-back working memory task while undergoing Blood Oxygen Level Dependent (BOLD) fMRI measurements. Fibromyalgia patients and controls did not differ in working memory performance. Subjective appraisal of cognitive function was associated with better performance (accuracy) on the working memory task in healthy controls but not in fibromyalgia patients. In fibromyalgia patients, increased perceived cognitive difficulty was positively correlated with the severity of their symptoms. BOLD response during the working memory task did not differ between the groups. BOLD response correlated with task accuracy in control subjects but not in fibromyalgia patients. Increased subjective cognitive impairment correlated with decreased BOLD response in both groups but in different anatomic regions. In conclusion, “fibrofog” appears to be better characterized by subjective rather than objective impairment. Neurologic correlates of this subjective experience of impairment might be separate from those involved in the performance of cognitive tasks. PMID:26955513

Characterizing "fibrofog": Subjective appraisal, objective performance, and task-related brain activity during a working memory task.

PubMed

Walitt, Brian; Čeko, Marta; Khatiwada, Manish; Gracely, John L; Rayhan, Rakib; VanMeter, John W; Gracely, Richard H

2016-01-01

The subjective experience of cognitive dysfunction ("fibrofog") is common in fibromyalgia. This study investigated the relation between subjective appraisal of cognitive function, objective cognitive task performance, and brain activity during a cognitive task using functional magnetic resonance imaging (fMRI). Sixteen fibromyalgia patients and 13 healthy pain-free controls completed a battery of questionnaires, including the Multiple Ability Self-Report Questionnaire (MASQ), a measure of self-perceived cognitive difficulties. Participants were evaluated for working memory performance using a modified N-back working memory task while undergoing Blood Oxygen Level Dependent (BOLD) fMRI measurements. Fibromyalgia patients and controls did not differ in working memory performance. Subjective appraisal of cognitive function was associated with better performance (accuracy) on the working memory task in healthy controls but not in fibromyalgia patients. In fibromyalgia patients, increased perceived cognitive difficulty was positively correlated with the severity of their symptoms. BOLD response during the working memory task did not differ between the groups. BOLD response correlated with task accuracy in control subjects but not in fibromyalgia patients. Increased subjective cognitive impairment correlated with decreased BOLD response in both groups but in different anatomic regions. In conclusion, "fibrofog" appears to be better characterized by subjective rather than objective impairment. Neurologic correlates of this subjective experience of impairment might be separate from those involved in the performance of cognitive tasks.

Psychological Empowerment on Organizational Commitment as Perceived by Saudi Academics

ERIC Educational Resources Information Center

Bin Jomah, Nouf

2017-01-01

Various scholars have identified commitment as one of the major contributors of workplace productivity. Commitment provides the interest and morale for handling tasks which results in organisation progress and growth. Commitment is perceived as either continuance, normative, or continuance commitment. The three commitment categories are…

Agency Culture and Climate in Child Welfare: Do Perceptions Vary by Exposure to the Child Welfare System?

PubMed Central

Spielfogel, Jill E.; Leathers, Sonya J.; Christian, Errick

2016-01-01

Organizational culture and climate play a critical role in worker retention and outcomes, yet little is known about whether perceptions of culture and climate vary depending on the demands of particular roles. In this study, 113 staff from a child welfare agency completed Organizational Social Context profiles. Staff were divided into three groups according to their proximity to child welfare tasks to assess whether involvement in higher stress child welfare tasks is related to perceptions of the social context. Findings suggest possible differences across groups, with those involved in core child welfare tasks appearing to perceive higher resistance to new ways of providing services and those with the least involvement in traditional child welfare perceiving a more positive social context overall. PMID:28261634

Agency Culture and Climate in Child Welfare: Do Perceptions Vary by Exposure to the Child Welfare System?

PubMed

Spielfogel, Jill E; Leathers, Sonya J; Christian, Errick

2016-01-01

Organizational culture and climate play a critical role in worker retention and outcomes, yet little is known about whether perceptions of culture and climate vary depending on the demands of particular roles. In this study, 113 staff from a child welfare agency completed Organizational Social Context profiles. Staff were divided into three groups according to their proximity to child welfare tasks to assess whether involvement in higher stress child welfare tasks is related to perceptions of the social context. Findings suggest possible differences across groups, with those involved in core child welfare tasks appearing to perceive higher resistance to new ways of providing services and those with the least involvement in traditional child welfare perceiving a more positive social context overall.

The mediating role of sleep quality on the relationship between perceived stress and depression among the elderly in urban communities: a cross-sectional study.

PubMed

Liu, Y; Li, T; Guo, L; Zhang, R; Feng, X; Liu, K

2017-08-01

This study aims to investigate the relationship between perceived stress, sleep quality, and depression among the elderly in urban communities, and further to determine whether sleep quality can serve as a mediator among the elderly in urban communities. A cross-sectional survey. Between May and July in 2015, we conducted a cross-sectional survey among 1050 community residents aged ≥60 years from Liaoning province, China. The Perceived Stress Scale, Pittsburgh Sleep Quality Index, and Epidemiological Studies Depression Scale were used to estimate perceived stress, sleep quality, and depression, respectively. The data were analyzed with correlation, multiple linear regression, and structural equation modeling. Of the 1050 participants surveyed, 1032 completed responses were ultimately acquired (98.3% effective response rate) and were included in the data analysis. Results revealed that the scores of perceived stress and sleep quality were positively correlated with Epidemiological Studies Depression Scale score. Sense of uncontrol, sense of nervous, sleep duration, and daytime dysfunction were identified as significant predictors of depression among the elderly. The effect of perceived stress on depression was partly mediated by sleep quality. Our study reveals that not all dimensions of sleep quality are relevant factors affecting depression in the elderly, and there may be partial mediation effects of sleep quality, mainly through sleep duration and daytime dysfunction, within the impact of perceived stress on depression. This signifies that coping with perceived stress can be expected to ameliorate the severity of depression in the elderly by the intermediary role of sleep quality as well as the direct effect. However, longitudinal research is needed to confirm these findings and to investigate other mediators between perceived stress and depression among the elderly. Copyright © 2017 The Royal Society for Public Health. Published by Elsevier Ltd. All rights reserved.

Brain Activations for Vestibular Stimulation and Dual Tasking Change with Spaceflight

NASA Technical Reports Server (NTRS)

Yuan, Peng; Koppelmans, Vincent; Reuter-Lorenz, Patricia; De Dios, Yiri; Gadd, Nichole; Wood, Scott; Riascos, Roy; Kofman, Igor; Bloomberg, Jacob; Mulavara, Ajitkumar;

Power plant maintenance scheduling using ant colony optimization: an improved formulation

NASA Astrophysics Data System (ADS)

Foong, Wai Kuan; Maier, Holger; Simpson, Angus

2008-04-01

It is common practice in the hydropower industry to either shorten the maintenance duration or to postpone maintenance tasks in a hydropower system when there is expected unserved energy based on current water storage levels and forecast storage inflows. It is therefore essential that a maintenance scheduling optimizer can incorporate the options of shortening the maintenance duration and/or deferring maintenance tasks in the search for practical maintenance schedules. In this article, an improved ant colony optimization-power plant maintenance scheduling optimization (ACO-PPMSO) formulation that considers such options in the optimization process is introduced. As a result, both the optimum commencement time and the optimum outage duration are determined for each of the maintenance tasks that need to be scheduled. In addition, a local search strategy is presented in this article to boost the robustness of the algorithm. When tested on a five-station hydropower system problem, the improved formulation is shown to be capable of allowing shortening of maintenance duration in the event of expected demand shortfalls. In addition, the new local search strategy is also shown to have significantly improved the optimization ability of the ACO-PPMSO algorithm.

Heart rate variability and cognitive processing: The autonomic response to task demands.

PubMed

Luque-Casado, Antonio; Perales, José C; Cárdenas, David; Sanabria, Daniel

2016-01-01

This study investigated variations in heart rate variability (HRV) as a function of cognitive demands. Participants completed an execution condition including the psychomotor vigilance task, a working memory task and a duration discrimination task. The control condition consisted of oddball versions (participants had to detect the rare event) of the tasks from the execution condition, designed to control for the effect of the task parameters (stimulus duration and stimulus rate) on HRV. The NASA-TLX questionnaire was used as a subjective measure of cognitive workload across tasks and conditions. Three major findings emerged from this study. First, HRV varied as a function of task demands (with the lowest values in the working memory task). Second, and crucially, we found similar HRV values when comparing each of the tasks with its oddball control equivalent, and a significant decrement in HRV as a function of time-on-task. Finally, the NASA-TLX results showed larger cognitive workload in the execution condition than in the oddball control condition, and scores variations as a function of task. Taken together, our results suggest that HRV is highly sensitive to overall demands of sustained attention over and above the influence of other cognitive processes suggested by previous literature. In addition, our study highlights a potential dissociation between objective and subjective measures of mental workload, with important implications in applied settings. Copyright © 2015 Elsevier B.V. All rights reserved.

Considering student choice when selecting instructional strategies: a comparison of three prompting systems.

PubMed

Taber-Doughty, Teresa

2005-01-01

Three secondary age students with moderate intellectual disabilities learned to use the system of least prompts, a self-operated picture prompting system, and a self-operated auditory prompting system to use a copy machine and a debit machine. Both the effectiveness and efficiency of these prompting systems were compared. Additionally, student preference of instructional method was examined. The results demonstrated that each prompting system was effective and efficient with varying students when skill acquisition and duration of task performance were measured. All students demonstrated increased independence in completing both tasks. This study found that the preferred prompting systems were more effective in terms of both skill acquisition and duration for completing tasks for students.

Division of Household and Childcare Labor and Relationship Conflict Among Low-Income New Parents

PubMed Central

Newkirk, Katie; Perry-Jenkins, Maureen; Sayer, Aline G.

2016-01-01

We examine the relationships among the division of housework and childcare labor, perceptions of its fairness for two types of family labor (housework and childcare), and parents’ relationship conflict across the transition to parenthood. Perceived fairness is examined as a mediator of the relationships between change in the division of housework and childcare and relationship conflict. Working-class, dual-earner couples (n = 108) in the U.S Northeast were interviewed at five time points from the third trimester of pregnancy and across the first year of parenthood. Research questions addressed whether change in the division of housework and childcare across the transition to parenthood predicted mothers’ and fathers’ relationship conflict, with attention to the mediating role of perceived fairness of these chores. Findings for housework indicated that perceived fairness was related to relationship conflict for mothers and fathers, such that when spouses perceived the change in the division of household tasks to be unfair to either partner, they reported more conflict, However, fairness did not significantly mediate relations between changes in division of household tasks and later relationship conflict. For childcare, fairness mediated relations between mothers’ violated expectations concerning the division of childcare and later conflict such that mothers reported less conflict when they perceived the division of childcare as less unfair to themselves; there was no relationship for fathers. Findings highlight the importance of considering both childcare and household tasks independently in our models and suggest that the division of housework and childcare holds different implications for mothers’ and fathers’ assessments of relationship conflict. PMID:28348454

Two forms of persistence in visual information processing.

PubMed

Di Lollo, Vincent; Dixon, Peter

1988-11-01

Iconic memory, which was initially regarded as a unitary phenomenon, has since been subdivided into several components. In the present work we examined the joint effects of two such components (visible persistence and the visual analog representation) on performance in a partial report task. The display consisted of 15 alphabetic characters arranged around the perimeter of an imaginary circle on the face of an oscilloscope. The observer named the character singled out by a bar-probe. Two factors were varied: exposure duration of the array (10, 50, 100, 150, 200, 300, 400 or 500 ms) and duration of blank period (interstimulus interval, ISI) between the termination of the array and the onset of the probe (0, 50, 100, 150, or 200 ms). Performance was progressively impaired as both exposure duration and ISI were increased. The results were explained in terms of a probabilistic combinatorial model in which the timecourses of visible persistence and of the visual analog representation are regarded as time-locked to the onset and to the end of stimulation, respectively. The impairing effect of exposure duration was attributed to the relatively high spatial demands of the task that could be met optimally by information in visible persistence (which declines as a function of exposure duration), but less adequately by information in the visual analog representation. A second experiment, employing a task with lesser spatial demands, confirmed this interpretation.

Using naturalistic driving study data to investigate the impact of driver distraction on driver's brake reaction time in freeway rear-end events in car-following situation.

PubMed

Gao, Jingru; Davis, Gary A

2017-12-01

The rear-end crash is one of the most common freeway crash types, and driver distraction is often cited as a leading cause of rear-end crashes. Previous research indicates that driver distraction could have negative effects on driving performance, but the specific association between driver distraction and crash risk is still not fully revealed. This study sought to understand the mechanism by which driver distraction, defined as secondary task distraction, could influence crash risk, as indicated by a driver's reaction time, in freeway car-following situations. A statistical analysis, exploring the causal model structure regarding drivers' distraction impacts on reaction times, was conducted. Distraction duration, distraction scenario, and secondary task type were chosen as distraction-related factors. Besides, exogenous factors including weather, visual obstruction, lighting condition, traffic density, and intersection presence and endogenous factors including driver age and gender were considered. There was an association between driver distraction and reaction time in the sample freeway rear-end events from SHRP 2 NDS database. Distraction duration, the distracted status when a leader braked, and secondary task type were related to reaction time, while all other factors showed no significant effect on reaction time. The analysis showed that driver distraction duration is the primary direct cause of the increase in reaction time, with other factors having indirect effects mediated by distraction duration. Longer distraction duration, the distracted status when a leader braked, and engaging in auditory-visual-manual secondary task tended to result in longer reaction times. Given drivers will be distracted occasionally, countermeasures which shorten distraction duration or avoid distraction presence while a leader vehicle brakes are worth considering. This study helps better understand the mechanism of freeway rear-end events in car-following situations, and provides a methodology that can be adopted to study the association between driver behavior and driving features. Copyright © 2017 National Safety Council and Elsevier Ltd. All rights reserved.

Out of mind, out of heart: attention affects duration of emotional experience.

PubMed

Freund, Alexandra M; Keil, Andreas

2013-01-01

It has been suggested that the extent to which a person maintains attention to pleasant versus unpleasant aspects of a given stimulus has an effect on the self-reported affective state. This assumption was empirically tested in two experiments. In Study 1, participants received the instruction either to focus on a positive emotion-eliciting event (winning a tournament chess game) or to focus their attention on an affectively neutral distraction task (describing drawings). Study 2 used negative performance feedback in a cognitive task to induce unpleasant affect and included three experimental groups (waiting condition, continuing with the same cognitive task, distraction by a different cognitive task). Results converged to show that distracting attention away from the emotion-eliciting event leads to a shorter duration of the emotional experience. These findings support the attention-focus hypothesis.

Observational Learning without a Model Is Influenced by the Observer's Possibility to Act: Evidence from the Simon Task

ERIC Educational Resources Information Center

Iani, Cristina; Rubichi, Sandro; Ferraro, Luca; Nicoletti, Roberto; Gallese, Vittorio

2013-01-01

We assessed whether observational learning in perceptual-motor tasks is affected by the visibility of an action producing perceived environmental effects and by the observer's possibility to act during observation. To this end, we conducted three experiments in which participants were required to observe a spatial compatibility task in which only…

The Impact of Reading Self-Efficacy and Task Value on Reading Comprehension Scores in Different Item Formats

ERIC Educational Resources Information Center

Solheim, Oddny Judith

2011-01-01

It has been hypothesized that students with low self-efficacy will struggle with complex reading tasks in assessment situations. In this study we examined whether perceived reading self-efficacy and reading task value uniquely predicted reading comprehension scores in two different item formats in a sample of fifth-grade students. Results showed…

Why Face a Challenge? The Reason behind Intrinsically Motivated Students' Spontaneous Choice of Challenging Tasks

ERIC Educational Resources Information Center

Inoue, Noriyuki

2007-01-01

In a task choice situation, why do some students spontaneously choose challenging tasks while others do not? In the study, 114 undergraduate students were first asked of their perceived competence and interest in solving number puzzles at both individual and situational levels, and then asked to choose one puzzle from four difficulty levels. They…

Influence of working memory and executive function on stair ascent and descent in young and older adults.

PubMed

Gaillardin, Florence; Baudry, Stéphane

2018-06-01

This study assessed the influence of attention division, working memory and executive function on stair ascent and descent in young and older adults. Twenty young (25.5 ± 2.1 yrs) and 20 older adults (68.4 ± 5.4 yrs) ascended and descended a 3-step staircase with no simultaneous cognitive task (single-motor task) or while performing a cognitive task (dual-task condition). The cognitive task involved either 1) recalling a word list of the subject's word-span minus 2 words (SPAN-2) to assess the attention division effect, 2) a word list of subject's word-span (SPAN-O) to assess the working memory effect, or 3) recalling in alphabetical order, a word list of the subject's word-span (SPAN-A) to assess the executive function effect. Word-span corresponds to the longest string of words that can be recalled correctly. The duration of ascent and descent of stairs was used to assess the cognitive-motor interaction. Stair ascent and descent duration did not differ between age groups for the single-motor task, and was similar between single-motor task and SPAN-2 in both groups (p > 0.05). In contrast, stair ascent and descent duration increased with SPAN-O compared with SPAN-2 for both groups (p < 0.01). Stair ascent (p = 0.017) and descent (p = 0.008) were longer in SPAN-A than SPAN-O only in older adults. Healthy aging was not associated with a decrease in the capacity to perform motor-cognitive dual tasks that involved ascending and descending of stairs when the cognitive task only required working memory. However, the decrease in dual-task performance involving executive functioning may reflect a subclinical cognitive decline in healthy older adults. Copyright © 2018 Elsevier Inc. All rights reserved.

Muscle activity, time to fatigue, and maximum task duration at different levels of production standard time

PubMed Central

Nur, Nurhayati Mohd; Dawal, Siti Zawiah Md; Dahari, Mahidzal; Sanusi, Junedah

2015-01-01

[Purpose] This study investigated the variations in muscle fatigue, time to fatigue, and maximum task duration at different levels of production standard time. [Methods] Twenty subjects performed repetitive tasks at three different levels of production standard time corresponding to “normal”, “hard” and “very hard”. Surface electromyography was used to measure the muscle activity. [Results] The results showed that muscle activity was significantly affected by the production standard time level. Muscle activity increased twice in percentage as the production standard time shifted from hard to very hard (6.9% vs. 12.9%). The muscle activity increased over time, indicating muscle fatigue. The muscle fatigue rate increased for the harder production standard time (Hard: 0.105; Very hard: 0.115), which indicated the associated higher risk of work-related musculoskeletal disorders. Muscle fatigue was also found to occur earlier for hard and very hard production standard times. [Conclusion] It is recommended that the maximum task duration should not exceed 5.6, 2.9, and 2.2 hours for normal, hard, and very hard production standard times, respectively, in order to maintain work performance and minimize the risk of work-related musculoskeletal disorders. PMID:26311974

Context effects in a temporal discrimination task" further tests of the Scalar Expectancy Theory and Learning-to-Time models.

PubMed

Arantes, Joana; Machado, Armando

2008-07-01

Pigeons were trained on two temporal bisection tasks, which alternated every two sessions. In the first task, they learned to choose a red key after a 1-s signal and a green key after a 4-s signal; in the second task, they learned to choose a blue key after a 4-s signal and a yellow key after a 16-s signal. Then the pigeons were exposed to a series of test trials in order to contrast two timing models, Learning-to-Time (LeT) and Scalar Expectancy Theory (SET). The models made substantially different predictions particularly for the test trials in which the sample duration ranged from 1 s to 16 s and the choice keys were Green and Blue, the keys associated with the same 4-s samples: LeT predicted that preference for Green should increase with sample duration, a context effect, but SET predicted that preference for Green should not vary with sample duration. The results were consistent with LeT. The present study adds to the literature the finding that the context effect occurs even when the two basic discriminations are never combined in the same session.

The Relationship between Perceived Training Opportunities, Work Motivation and Employee Outcomes

ERIC Educational Resources Information Center

Dysvik, Anders; Kuvaas, Bard

2008-01-01

The purpose of this study was to explore alternative relationships between training opportunities and employee outcomes. A cross-sectional survey of 343 trainees from a broad range of Norwegian service organizations showed that the relationship between perceived training opportunities, and both task performance and citizenship behaviors were fully…

Undergraduates' Perceived Knowledge, Self-Efficacy, and Interest in Social Science Research

ERIC Educational Resources Information Center

Boswell, Stefanie S.

2013-01-01

This study investigated the relationship between perceived knowledge of research methods, research self-efficacy, interest in learning about research, and interest in performing research-related tasks in one's career. The study also investigated the effect of a research methods course with both didactic and experiential components on these…

Perceived Reachability in Hemispace

ERIC Educational Resources Information Center

Gabbard, C.; Ammar, D.; Rodrigues, L.

2005-01-01

A common observation in studies of perceived (imagined) compared to actual movement in a reaching paradigm is the tendency to overestimate. Of the studies noted, reaching tasks have been presented in the general midline range. In the present study, strong right-handers were asked to judge the reachability of visual targets projected onto a table…

Can Cognitive Activities during Breaks in Repetitive Manual Work Accelerate Recovery from Fatigue? A Controlled Experiment

PubMed Central

Mathiassen, Svend Erik; Hallman, David M.; Lyskov, Eugene; Hygge, Staffan

2014-01-01

Neurophysiologic theory and some empirical evidence suggest that fatigue caused by physical work may be more effectively recovered during “diverting” periods of cognitive activity than during passive rest; a phenomenon of great interest in working life. We investigated the extent to which development and recovery of fatigue during repeated bouts of an occupationally relevant reaching task was influenced by the difficulty of a cognitive activity between these bouts. Eighteen male volunteers performed three experimental sessions, consisting of six 7-min bouts of reaching alternating with 3 minutes of a memory test differing in difficulty between sessions. Throughout each session, recordings were made of upper trapezius muscle activity using electromyography (EMG), heart rate and heart rate variability (HRV) using electrocardiography, arterial blood pressure, and perceived fatigue (Borg CR10 scale and SOFI). A test battery before, immediately after and 1 hour after the work period included measurements of maximal shoulder elevation strength (MVC), pressure pain threshold (PPT) over the trapezius muscles, and a submaximal isometric contraction. As expected, perceived fatigue and EMG amplitude increased during the physical work bouts. Recovery did occur between the bouts, but fatigue accumulated throughout the work period. Neither EMG changes nor recovery of perceived fatigue during breaks were influenced by cognitive task difficulty, while heart rate and HRV recovered the most during breaks with the most difficult task. Recovery of perceived fatigue after the 1 hour work period was also most pronounced for the most difficult cognitive condition, while MVC and PPT showed ambiguous patterns, and EMG recovered similarly after all three cognitive protocols. Thus, we could confirm that cognitive tasks between bouts of fatiguing physical work can, indeed, accelerate recovery of some factors associated with fatigue, even if benefits may be moderate and some responses may be equivocal. Our results encourage further research into combinations of physical and mental tasks in an occupational context. PMID:25375644

The effect of a standardised source of divided attention in airway management: A randomised, crossover, interventional manikin study.

PubMed

Prottengeier, Johannes; Petzoldt, Marlen; Jess, Nikola; Moritz, Andreas; Gall, Christine; Schmidt, Joachim; Breuer, Georg

2016-03-01

Dual-tasking, the need to divide attention between concurrent tasks, causes a severe increase in workload in emergency situations and yet there is no standardised training simulation scenario for this key difficulty. We introduced and validated a quantifiable source of divided attention and investigated its effects on performance and workload in airway management. A randomised, crossover, interventional simulation study. Center for Training and Simulation, Department of Anaesthesiology, Erlangen University Hospital, Germany. One hundred and fifty volunteer medical students, paramedics and anaesthesiologists of all levels of training. Participants secured the airway of a manikin using a supraglottic airway, conventional endotracheal intubation and video-assisted endotracheal intubation with and without the Paced Auditory Serial Addition Test (PASAT), which served as a quantifiable source of divided attention. Primary endpoint was the time for the completion of each airway task. Secondary endpoints were the number of procedural mistakes made and the perceived workload as measured by the National Aeronautics and Space Administration's task load index (NASA-TLX). This is a six-dimensional questionnaire, which assesses the perception of demands, performance and frustration with respect to a task on a scale of 0 to 100. All 150 participants completed the tests. Volunteers perceived our test to be challenging (99%) and the experience of stress and distraction true to an emergency situation (80%), but still fair (98%) and entertaining (95%). The negative effects of divided attention were reproducible in participants of all levels of expertise. Time consumption and perceived workload increased and almost half the participants make procedural mistakes under divided attention. The supraglottic airway technique was least affected by divided attention. The scenario was effective for simulation training involving divided attention in acute care medicine. The significant effects on performance and perceived workload demonstrate the validity of the model, which was also characterised by high acceptability, technical simplicity and a novel degree of standardisation.

Perception of time in microgravity and hypergravity during parabolic flight.

PubMed

Clément, Gilles

2018-03-07

We explored the effect of gravity on the accuracy for estimating durations of 3.5, 7, and 14 s. Experiments were performed on board an Airbus A310 during parabolic flights eliciting repeated exposures to short periods of 0, 1, and 1.8 g. Two methods for obtaining duration estimates were used, reproduction and production of duration, in two conditions: a control counting condition and a concurrent reading condition. Simple reaction times were also measured to assess attention. The results showed that the temporal accuracies during the reproduction task in the concurrent reading condition were significantly underestimated in 0 g compared with 1 g. Reaction times were also longer in 0 g. However, there was no difference in duration estimates in the production tasks. These results suggest that the temporal underestimation in 0 g is caused by decreased selective attention and impaired retrieval of information in episodic memory.

Individual differences in first- and second-order temporal judgment.

PubMed

Corcoran, Andrew W; Groot, Christopher; Bruno, Aurelio; Johnston, Alan; Cropper, Simon J

2018-01-01

The ability of subjects to identify and reproduce brief temporal intervals is influenced by many factors whether they be stimulus-based, task-based or subject-based. The current study examines the role individual differences play in subsecond and suprasecond timing judgments, using the schizoptypy personality scale as a test-case approach for quantifying a broad range of individual differences. In two experiments, 129 (Experiment 1) and 141 (Experiment 2) subjects completed the O-LIFE personality questionnaire prior to performing a modified temporal-bisection task. In the bisection task, subjects responded to two identical instantiations of a luminance grating presented in a 4deg window, 4deg above fixation for 1.5 s (Experiment 1) or 3 s (Experiment 2). Subjects initiated presentation with a button-press, and released the button when they considered the stimulus to be half-way through (750/1500 ms). Subjects were then asked to indicate their 'most accurate estimate' of the two intervals. In this way we measure both performance on the task (a first-order measure) and the subjects' knowledge of their performance (a second-order measure). In Experiment 1 the effect of grating-drift and feedback on performance was also examined. Experiment 2 focused on the static/no-feedback condition. For the group data, Experiment 1 showed a significant effect of presentation order in the baseline condition (no feedback), which disappeared when feedback was provided. Moving the stimulus had no effect on perceived duration. Experiment 2 showed no effect of stimulus presentation order. This elimination of the subsecond order-effect was at the expense of accuracy, as the mid-point of the suprasecond interval was generally underestimated. Response precision increased as a proportion of total duration, reducing the variance below that predicted by Weber's law. This result is consistent with a breakdown of the scalar properties of time perception in the early suprasecond range. All subjects showed good insight into their own performance, though that insight did not necessarily correlate with the veridical bisection point. In terms of personality, we found evidence of significant differences in performance along the Unusual Experiences subscale, of most theoretical interest here, in the subsecond condition only. There was also significant correlation with Impulsive Nonconformity and Cognitive Disorganisation in the sub- and suprasecond conditions, respectively. Overall, these data support a partial dissociation of timing mechanisms at very short and slightly longer intervals. Further, these results suggest that perception is not the only critical mitigator of confidence in temporal experience, since individuals can effectively compensate for differences in perception at the level of metacognition in early suprasecond time. Though there are individual differences in performance, these are perhaps less than expected from previous reports and indicate an effective timing mechanism dealing with brief durations independent of the influence of significant personality trait differences.

Effect of different types of music on exercise performance in normal individuals.

PubMed

Thakur, Anuprita M; Yardi, Sujata S

2013-01-01

While exercising, people seem to enjoy listening to music believing that it relaxes them or helps give the necessary rhythm for exercise. But is music really beneficial? In view of different people listening to different types of music, this study was intended to assess effect of different types of music on exercise performance. 30 healthy female college students in the age group of 18 to 25 years were made to walk on the treadmill 3 times at one week interval: without music (A), with slow music (B), with fast music (C). Duration of exercise and rate of perceived exertion were recorded at the end of each session. The results showed an increase in the duration of exercise in Group B and Group C as compared to Group A and the increase was more in Group C as compared to Group B. It was observed that level of RPE was the same at the end of every exercise session. The reason for increase in exercise duration with music could be because of various factors like dissociation, arousal, motivation, etc. It can be thus suggested that exercises can be performed for longer duration with music than without music and the effect is more with fast music than with slow music. Also with music, the same level of exertion is perceived though the walking duration is considerably increased.

Mental workload during brain-computer interface training.

PubMed

Felton, Elizabeth A; Williams, Justin C; Vanderheiden, Gregg C; Radwin, Robert G

2012-01-01

It is not well understood how people perceive the difficulty of performing brain-computer interface (BCI) tasks, which specific aspects of mental workload contribute the most, and whether there is a difference in perceived workload between participants who are able-bodied and disabled. This study evaluated mental workload using the NASA Task Load Index (TLX), a multi-dimensional rating procedure with six subscales: Mental Demands, Physical Demands, Temporal Demands, Performance, Effort, and Frustration. Able-bodied and motor disabled participants completed the survey after performing EEG-based BCI Fitts' law target acquisition and phrase spelling tasks. The NASA-TLX scores were similar for able-bodied and disabled participants. For example, overall workload scores (range 0-100) for 1D horizontal tasks were 48.5 (SD = 17.7) and 46.6 (SD 10.3), respectively. The TLX can be used to inform the design of BCIs that will have greater usability by evaluating subjective workload between BCI tasks, participant groups, and control modalities. Mental workload of brain-computer interfaces (BCI) can be evaluated with the NASA Task Load Index (TLX). The TLX is an effective tool for comparing subjective workload between BCI tasks, participant groups (able-bodied and disabled), and control modalities. The data can inform the design of BCIs that will have greater usability.

Impact of simulated three-dimensional perception on precision of depth judgements, technical performance and perceived workload in laparoscopy.

PubMed

Sakata, S; Grove, P M; Hill, A; Watson, M O; Stevenson, A R L

2017-07-01

This study compared precision of depth judgements, technical performance and workload using two-dimensional (2D) and three-dimensional (3D) laparoscopic displays across different viewing distances. It also compared the accuracy of 3D displays with natural viewing, along with the relationship between stereoacuity and 3D laparoscopic performance. A counterbalanced within-subjects design with random assignment to testing sequences was used. The system could display 2D or 3D images with the same set-up. A Howard-Dolman apparatus assessed precision of depth judgements, and three laparoscopic tasks (peg transfer, navigation in space and suturing) assessed performance (time to completion). Participants completed tasks in all combinations of two viewing modes (2D, 3D) and two viewing distances (1 m, 3 m). Other measures administered included the National Aeronautics and Space Administration Task Load Index (perceived workload) and the Randot ® Stereotest (stereoacuity). Depth judgements were 6·2 times as precise at 1 m and 3·0 times as precise at 3 m using 3D versus 2D displays (P < 0·001). Participants performed all laparoscopic tasks faster in 3D at both 1 and 3 m (P < 0.001), with mean completion times up to 64 per cent shorter for 3D versus 2D displays. Workload was lower for 3D displays (up to 34 per cent) than for 2D displays at both viewing distances (P < 0·001). Greater viewing distance inhibited performance for two laparoscopic tasks, and increased perceived workload for all three (P < 0·001). Higher stereoacuity was associated with shorter completion times for the navigating in space task performed in 3D at 1 m (r = - 0·40, P = 0·001). 3D displays offer large improvements over 2D displays in precision of depth judgements, technical performance and perceived workload. © 2017 The Authors. BJS published by John Wiley & Sons Ltd on behalf of BJS Society Ltd.

Perceived Conventionality in Co-speech Gestures Involves the Fronto-Temporal Language Network.

PubMed

Wolf, Dhana; Rekittke, Linn-Marlen; Mittelberg, Irene; Klasen, Martin; Mathiak, Klaus

2017-01-01

Face-to-face communication is multimodal; it encompasses spoken words, facial expressions, gaze, and co-speech gestures. In contrast to linguistic symbols (e.g., spoken words or signs in sign language) relying on mostly explicit conventions, gestures vary in their degree of conventionality. Bodily signs may have a general accepted or conventionalized meaning (e.g., a head shake) or less so (e.g., self-grooming). We hypothesized that subjective perception of conventionality in co-speech gestures relies on the classical language network, i.e., the left hemispheric inferior frontal gyrus (IFG, Broca's area) and the posterior superior temporal gyrus (pSTG, Wernicke's area) and studied 36 subjects watching video-recorded story retellings during a behavioral and an functional magnetic resonance imaging (fMRI) experiment. It is well documented that neural correlates of such naturalistic videos emerge as intersubject covariance (ISC) in fMRI even without involving a stimulus (model-free analysis). The subjects attended either to perceived conventionality or to a control condition (any hand movements or gesture-speech relations). Such tasks modulate ISC in contributing neural structures and thus we studied ISC changes to task demands in language networks. Indeed, the conventionality task significantly increased covariance of the button press time series and neuronal synchronization in the left IFG over the comparison with other tasks. In the left IFG, synchronous activity was observed during the conventionality task only. In contrast, the left pSTG exhibited correlated activation patterns during all conditions with an increase in the conventionality task at the trend level only. Conceivably, the left IFG can be considered a core region for the processing of perceived conventionality in co-speech gestures similar to spoken language. In general, the interpretation of conventionalized signs may rely on neural mechanisms that engage during language comprehension.

Perceived Conventionality in Co-speech Gestures Involves the Fronto-Temporal Language Network

PubMed Central

Wolf, Dhana; Rekittke, Linn-Marlen; Mittelberg, Irene; Klasen, Martin; Mathiak, Klaus

2017-01-01

Face-to-face communication is multimodal; it encompasses spoken words, facial expressions, gaze, and co-speech gestures. In contrast to linguistic symbols (e.g., spoken words or signs in sign language) relying on mostly explicit conventions, gestures vary in their degree of conventionality. Bodily signs may have a general accepted or conventionalized meaning (e.g., a head shake) or less so (e.g., self-grooming). We hypothesized that subjective perception of conventionality in co-speech gestures relies on the classical language network, i.e., the left hemispheric inferior frontal gyrus (IFG, Broca's area) and the posterior superior temporal gyrus (pSTG, Wernicke's area) and studied 36 subjects watching video-recorded story retellings during a behavioral and an functional magnetic resonance imaging (fMRI) experiment. It is well documented that neural correlates of such naturalistic videos emerge as intersubject covariance (ISC) in fMRI even without involving a stimulus (model-free analysis). The subjects attended either to perceived conventionality or to a control condition (any hand movements or gesture-speech relations). Such tasks modulate ISC in contributing neural structures and thus we studied ISC changes to task demands in language networks. Indeed, the conventionality task significantly increased covariance of the button press time series and neuronal synchronization in the left IFG over the comparison with other tasks. In the left IFG, synchronous activity was observed during the conventionality task only. In contrast, the left pSTG exhibited correlated activation patterns during all conditions with an increase in the conventionality task at the trend level only. Conceivably, the left IFG can be considered a core region for the processing of perceived conventionality in co-speech gestures similar to spoken language. In general, the interpretation of conventionalized signs may rely on neural mechanisms that engage during language comprehension. PMID:29249945

Restoration of Hindlimb Movements after Complete Spinal Cord Injury Using Brain-Controlled Functional Electrical Stimulation.

PubMed

Knudsen, Eric B; Moxon, Karen A

2017-01-01

Single neuron and local field potential signals recorded in the primary motor cortex have been repeatedly demonstrated as viable control signals for multi-degree-of-freedom actuators. Although the primary source of these signals has been fore/upper limb motor regions, recent evidence suggests that neural adaptation underlying neuroprosthetic control is generalizable across cortex, including hindlimb sensorimotor cortex. Here, adult rats underwent a longitudinal study that included a hindlimb pedal press task in response to cues for specific durations, followed by brain machine interface (BMI) tasks in healthy rats, after rats received a complete spinal transection and after the BMI signal controls epidural stimulation (BMI-FES). Over the course of the transition from learned behavior to BMI task, fewer neurons were responsive after the cue, the proportion of neurons selective for press duration increased and these neurons carried more information. After a complete, mid-thoracic spinal lesion that completely severed both ascending and descending connections to the lower limbs, there was a reduction in task-responsive neurons followed by a reacquisition of task selectivity in recorded populations. This occurred due to a change in pattern of neuronal responses not simple changes in firing rate. Finally, during BMI-FES, additional information about the intended press duration was produced. This information was not dependent on the stimulation, which was the same for short and long duration presses during the early phase of stimulation, but instead was likely due to sensory feedback to sensorimotor cortex in response to movement along the trunk during the restored pedal press. This post-cue signal could be used as an error signal in a continuous decoder providing information about the position of the limb to optimally control a neuroprosthetic device.

Prospective Fathers: Psychosocial Adaptation and Involvement in the Last Trimester of Pregnancy.

PubMed

Kuljanić, Karin; Dorčić, Tamara Martinac; Bistrović, Ivana Ljubičić; Brnčić-Fischer, Alemka

2016-12-01

Paternal involvement in pregnancy has been recognized to have an impact on new-born's outcomes and only recently got under the spot light of mental health perspective. The aim of this study was to test differences in paternal involvement in pregnancy, perceived stress and relationship quality regarding complications in pregnancy and pregnancy duration (gestational weeks) in the last trimester of pregnancy. The role of personality traits (neuroticism and extroversion), relationship quality satisfaction and perceived stress in prospective father's perception of pregnancy involvement were examined. One-hundred forty-three primiparus couples in the last trimester of their pregnancy participated in the study. Prospective fathers completed a booklet with questionnaires including The Quality of Marriage Index, The Perceived Stress Scale, Eysenck Personality Questionnaire and Partner's Involvement in Pregnancy Scale. Prospective mothers completed only Eysenck Personality Questionnaire and questions on pregnancy complications and demographics. The prospective fathers showed high involvement in their partner's pregnancies, elevated levels of perceived stress and high relationship quality. There were found no differences in the above named variables regarding complications in pregnancy and pregnancy duration. Higher involvement of prospective fathers was related with older age, lower male neuroticism and higher female extroversion, better relationship quality and lower perceived stress. The findings demonstrate that prospective father's involvement in pregnancy is supported with psychological factors, namely personality traits, quality of relationship and perceived stress. These results should lead to target interventions that can modify and improve fathers' involvement perspective and promoting a couples mental health during pregnancy: thus clinically important for promotion of healthy prenatal behaviour and decrease in mothers' emotional distress.

The return of bedside rounds: an educational intervention.

PubMed

Gonzalo, Jed D; Chuang, Cynthia H; Huang, Grace; Smith, Christopher

2010-08-01

Bedside rounds have decreased in frequency on teaching services. Perceived barriers toward bedside rounds are inefficiency and patient and house staff lack of preference for this mode of rounding. To evaluate the impact of a bedside rounding intervention on the frequency of bedside rounding, duration of patient encounters and rounding sessions, and patient and resident attitudes toward bedside rounds. A pre- and postintervention design, with a bedside rounding workshop midway through two consecutive internal medicine rotations, with daily resident interviews, patient surveys, and an end-of-the-year survey given to all Medicine house staff. Medicine house staff and medicine patients. Frequency of bedside rounds, duration of new patient encounters and rounding sessions, and patient and house staff attitudes regarding bedside rounds. Forty-four residents completed the bedside rounding workshop. Comparing the preintervention and postintervention phases, bedside rounds increased from <1% to 41% (p < 0.001). The average duration of walk rounding encounters was 16 min, and average duration of bedside rounding encounters was 15 min (p = 0.42). Duration of rounds was 95 and 98 min, respectively (p = 0.52). Patients receiving bedside rounds preferred bedside rounds (99% vs. 83%, p = 0.03) and perceived more time spent at the bedside by their team (p < 0.001). One hundred twelve house staff (71%) responded, with 73% reporting that bedside rounds are better for patient care. House staff performing bedside rounds were less likely to believe that bedside rounds were more educational (53% vs. 78%, p = 0.01). Bedside rounding increased after an educational intervention, and the time to complete bedside rounding encounters was similar to alternative forms of rounding. Patients preferred bedside rounds and perceived more time spent at the bedside when receiving bedside rounds. Medicine residents performing bedside rounds were less likely to believe bedside rounds were more educational, but all house staff valued the importance of bedside rounding for the delivery of patient care.

The Return of Bedside Rounds: An Educational Intervention

PubMed Central

Gonzalo, Jed D.; Chuang, Cynthia H.; Huang, Grace

2010-01-01

Background Bedside rounds have decreased in frequency on teaching services. Perceived barriers toward bedside rounds are inefficiency and patient and house staff lack of preference for this mode of rounding. Objectives To evaluate the impact of a bedside rounding intervention on the frequency of bedside rounding, duration of patient encounters and rounding sessions, and patient and resident attitudes toward bedside rounds. Design A pre- and postintervention design, with a bedside rounding workshop midway through two consecutive internal medicine rotations, with daily resident interviews, patient surveys, and an end-of-the-year survey given to all Medicine house staff. Participants Medicine house staff and medicine patients. Measures Frequency of bedside rounds, duration of new patient encounters and rounding sessions, and patient and house staff attitudes regarding bedside rounds. Results Forty-four residents completed the bedside rounding workshop. Comparing the preintervention and postintervention phases, bedside rounds increased from <1% to 41% (p < 0.001). The average duration of walk rounding encounters was 16 min, and average duration of bedside rounding encounters was 15 min (p = 0.42). Duration of rounds was 95 and 98 min, respectively (p = 0.52). Patients receiving bedside rounds preferred bedside rounds (99% vs. 83%, p = 0.03) and perceived more time spent at the bedside by their team (p < 0.001). One hundred twelve house staff (71%) responded, with 73% reporting that bedside rounds are better for patient care. House staff performing bedside rounds were less likely to believe that bedside rounds were more educational (53% vs. 78%, p = 0.01). Conclusions Bedside rounding increased after an educational intervention, and the time to complete bedside rounding encounters was similar to alternative forms of rounding. Patients preferred bedside rounds and perceived more time spent at the bedside when receiving bedside rounds. Medicine residents performing bedside rounds were less likely to believe bedside rounds were more educational, but all house staff valued the importance of bedside rounding for the delivery of patient care. PMID:20386997

Are stimulus-response rules represented phonologically for task-set preparation and maintenance?

PubMed

van 't Wout, Félice; Lavric, Aureliu; Monsell, Stephen

2013-09-01

Accounts of task-set control generally assume that the current task's stimulus-response (S-R) rules must be elevated to a privileged state of activation. How are they represented in this state? In 3 task-cuing experiments, we tested the hypothesis that phonological working memory is used to represent S-R rules for task-set control by getting participants to switch between 2 sets of arbitrary S-R rules and manipulating the articulatory duration (Experiment 1) or phonological similarity (Experiments 2 and 3) of the names of the stimulus terms. The task cue specified which of 2 objects (Experiment 1) or consonants (Experiment 2) in a display to identify with a key press. In Experiment 3, participants switched between identifying an object/consonant and its color/visual texture. After practice, neither the duration nor the similarity of the stimulus terms had detectable effects on overall performance, task-switch cost, or its reduction with preparation. Only in the initial single-task training blocks was phonological similarity a significant handicap. Hence, beyond a very transient role, there is no evidence that (declarative) phonological working memory makes a functional contribution to representing S-R rules for task-set control, arguably because once learned, they are represented in nonlinguistic procedural working memory. PsycINFO Database Record (c) 2013 APA, all rights reserved.

Is task-shifting a solution to the health workers' shortage in Northern Ghana?

PubMed

Okyere, Eunice; Mwanri, Lillian; Ward, Paul

2017-01-01

To explore the experiences and perceptions of health workers and implementers of task-shifting in rural health facilities in Upper East Region, Ghana. Data was collected through field interviews. A total of sixty eight (68) in-depth interviews were conducted with health workers' in primary health care facilities (health centres); Four in-depth interviews with key persons involved in staff management was conducted to understand how task-shifting is organised including its strengths and challenges. The health workers interview guide was designed with the aim of getting data on official tasks of health workers, additional tasks assigned to them, how they perceive these tasks, and the challenges associated with the practice of task-shifting. Task-shifting is a practice being used across the health facilities in the study area to help reduce the impact of insufficient health workers. Generally, health workers had a comprehensive training that supported the organisation of task-shifting. However, staff members' are sometimes engaged in tasks above their level of training and beyond their actual job descriptions. Adequate training is usually not provided before additional tasks are assigned to staff members. Whilst some health workers perceived the additional tasks they performed as an opportunity to learn new skills, others described these as stressful and overburdening. Task-shifting has the potential to contribute to addressing the insufficient health workforce, and thereby improving health delivery system where the procedures are well defined and staff members work in a coordinated and organised manner. The provision of adequate training and supervision for health workers is important in order to improve their expertise before additional tasks are assigned to them so that the quality of care would not be compromised.

Is task-shifting a solution to the health workers’ shortage in Northern Ghana?

PubMed Central

Okyere, Eunice; Mwanri, Lillian; Ward, Paul

2017-01-01

Objective To explore the experiences and perceptions of health workers and implementers of task-shifting in rural health facilities in Upper East Region, Ghana. Methods Data was collected through field interviews. A total of sixty eight (68) in-depth interviews were conducted with health workers’ in primary health care facilities (health centres); Four in-depth interviews with key persons involved in staff management was conducted to understand how task-shifting is organised including its strengths and challenges. The health workers interview guide was designed with the aim of getting data on official tasks of health workers, additional tasks assigned to them, how they perceive these tasks, and the challenges associated with the practice of task-shifting. Findings Task-shifting is a practice being used across the health facilities in the study area to help reduce the impact of insufficient health workers. Generally, health workers had a comprehensive training that supported the organisation of task-shifting. However, staff members’ are sometimes engaged in tasks above their level of training and beyond their actual job descriptions. Adequate training is usually not provided before additional tasks are assigned to staff members. Whilst some health workers perceived the additional tasks they performed as an opportunity to learn new skills, others described these as stressful and overburdening. Conclusion Task-shifting has the potential to contribute to addressing the insufficient health workforce, and thereby improving health delivery system where the procedures are well defined and staff members work in a coordinated and organised manner. The provision of adequate training and supervision for health workers is important in order to improve their expertise before additional tasks are assigned to them so that the quality of care would not be compromised. PMID:28358841

The extended Theory of Planned Behavior in explaining exclusive breastfeeding intention and behavior among women in Kelantan, Malaysia.

PubMed

Tengku Ismail, Tengku Alina; Wan Muda, Wan Abdul Manan; Bakar, Mohd Isa

2016-02-01

The purpose of this study is to utilize an extended Theory of Planned Behavior in identifying predictors of exclusive breastfeeding intention and behavior among women in Kelantan, Malaysia. A prospective cohort study was conducted, recruiting pregnant womenthrough two-stage cluster sampling. Their exclusive breastfeeding intention, attitude, perceived norm, perceived behavioral control and past behavior were obtained at baseline through interviewer-guided questionnaire. At one month after delivery, another interview was conducted to determine the two additional variables in the extended theory, which were their postpartum support and breastfeeding difficulty. The behavior, which was the actual duration of exclusive breastfeeding, was obtained from the second follow-up at six months. Pearson correlation and two hierarchical regression analyses were conducted. A total of 200 women completed the study follow-up. Their median intended exclusive breastfeeding duration was 4.0 (IQR 5) months, and the median actual duration was 1.0 (IQR 4) month. The Theory of Planned Behavior explained 51.0% of the variance in intention, with perceived behavioral control and attitude were the significant predictors. It also explained 10.0% of the variance in behavior, but the addition of postpartum support and breastfeeding difficulty increased the amount of explained variance in behavior by 6.0%. The significant predictors of exclusive breastfeeding behavior were intention, postpartum support and breastfeeding difficulty. The extended Theory of Planned Behaviorhad a good predictive ability in explaining exclusive breastfeedingintention and behavior. The women's intention to practice exclusive breastfeeding may be improved by improving their perceived behavioral control and attitude. Providing correct postpartum support and skills to handle breastfeeding difficulties after delivery will improve their exclusive breastfeeding behavior.

The extended Theory of Planned Behavior in explaining exclusive breastfeeding intention and behavior among women in Kelantan, Malaysia

PubMed Central

Wan Muda, Wan Abdul Manan; Bakar, Mohd Isa

2016-01-01

BACKGROUND/OBJECTIVES The purpose of this study is to utilize an extended Theory of Planned Behavior in identifying predictors of exclusive breastfeeding intention and behavior among women in Kelantan, Malaysia. SUBJECTS/METHODS A prospective cohort study was conducted, recruiting pregnant womenthrough two-stage cluster sampling. Their exclusive breastfeeding intention, attitude, perceived norm, perceived behavioral control and past behavior were obtained at baseline through interviewer-guided questionnaire. At one month after delivery, another interview was conducted to determine the two additional variables in the extended theory, which were their postpartum support and breastfeeding difficulty. The behavior, which was the actual duration of exclusive breastfeeding, was obtained from the second follow-up at six months. Pearson correlation and two hierarchical regression analyses were conducted. RESULTS A total of 200 women completed the study follow-up. Their median intended exclusive breastfeeding duration was 4.0 (IQR 5) months, and the median actual duration was 1.0 (IQR 4) month. The Theory of Planned Behavior explained 51.0% of the variance in intention, with perceived behavioral control and attitude were the significant predictors. It also explained 10.0% of the variance in behavior, but the addition of postpartum support and breastfeeding difficulty increased the amount of explained variance in behavior by 6.0%. The significant predictors of exclusive breastfeeding behavior were intention, postpartum support and breastfeeding difficulty. CONCLUSION The extended Theory of Planned Behaviorhad a good predictive ability in explaining exclusive breastfeedingintention and behavior. The women's intention to practice exclusive breastfeeding may be improved by improving their perceived behavioral control and attitude. Providing correct postpartum support and skills to handle breastfeeding difficulties after delivery will improve their exclusive breastfeeding behavior. PMID:26865916

Impact of virtual reality simulation on learning barriers of phacoemulsification perceived by residents.

PubMed

Ng, Danny Siu-Chun; Sun, Zihan; Young, Alvin Lerrmann; Ko, Simon Tak-Chuen; Lok, Jerry Ka-Hing; Lai, Timothy Yuk-Yau; Sikder, Shameema; Tham, Clement C

2018-01-01

To identify residents' perceived barriers to learning phacoemulsification surgical procedures and to evaluate whether virtual reality simulation training changed these perceptions. The ophthalmology residents undertook a simulation phacoemulsification course and proficiency assessment on the Eyesi system using the previously validated training modules of intracapsular navigation, anti-tremor, capsulorrhexis, and cracking/chopping. A cross-sectional, multicenter survey on the perceived difficulties in performing phacoemulsification tasks on patients, based on the validated International Council of Ophthalmology's Ophthalmology Surgical Competency Assessment Rubric (ICO-OSCAR), using a 5-point Likert scale (1 = least and 5 = most difficulty), was conducted among residents with or without prior simulation training. Mann-Whitney U tests were carried out to compare the mean scores, and multivariate regression analyses were performed to evaluate the association of lower scores with the following potential predictors: 1) higher level trainee, 2) can complete phacoemulsification most of the time (>90%) without supervisor's intervention, and 3) prior simulation training. The study was conducted in ophthalmology residency training programs in five regional hospitals in Hong Kong. Of the 22 residents, 19 responded (86.3%), of which 13 (68.4%) had completed simulation training. Nucleus cracking/chopping was ranked highest in difficulty by all respondents followed by capsulorrhexis completion and nucleus rotation/manipulation. Respondents with prior simulation training had significantly lower difficulty scores on these three tasks (nucleus cracking/chopping 3.85 vs 4.75, P = 0.03; capsulorrhexis completion 3.31 vs 4.40, P = 0.02; and nucleus rotation/manipulation 3.00 vs 4.75, P = 0.01). In multivariate analyses, simulation training was significantly associated with lower difficulty scores on these three tasks. Residents who had completed Eyesi simulation training had higher confidence in performing the most difficult tasks perceived during phacoemulsification.

Impact of virtual reality simulation on learning barriers of phacoemulsification perceived by residents

PubMed Central

Ng, Danny Siu-Chun; Sun, Zihan; Young, Alvin Lerrmann; Ko, Simon Tak-Chuen; Lok, Jerry Ka-Hing; Lai, Timothy Yuk-Yau; Sikder, Shameema; Tham, Clement C

2018-01-01

Objective To identify residents’ perceived barriers to learning phacoemulsification surgical procedures and to evaluate whether virtual reality simulation training changed these perceptions. Design The ophthalmology residents undertook a simulation phacoemulsification course and proficiency assessment on the Eyesi system using the previously validated training modules of intracapsular navigation, anti-tremor, capsulorrhexis, and cracking/chopping. A cross-sectional, multicenter survey on the perceived difficulties in performing phacoemulsification tasks on patients, based on the validated International Council of Ophthalmology’s Ophthalmology Surgical Competency Assessment Rubric (ICO-OSCAR), using a 5-point Likert scale (1 = least and 5 = most difficulty), was conducted among residents with or without prior simulation training. Mann–Whitney U tests were carried out to compare the mean scores, and multivariate regression analyses were performed to evaluate the association of lower scores with the following potential predictors: 1) higher level trainee, 2) can complete phacoemulsification most of the time (>90%) without supervisor’s intervention, and 3) prior simulation training. Setting The study was conducted in ophthalmology residency training programs in five regional hospitals in Hong Kong. Results Of the 22 residents, 19 responded (86.3%), of which 13 (68.4%) had completed simulation training. Nucleus cracking/chopping was ranked highest in difficulty by all respondents followed by capsulorrhexis completion and nucleus rotation/manipulation. Respondents with prior simulation training had significantly lower difficulty scores on these three tasks (nucleus cracking/chopping 3.85 vs 4.75, P = 0.03; capsulorrhexis completion 3.31 vs 4.40, P = 0.02; and nucleus rotation/manipulation 3.00 vs 4.75, P = 0.01). In multivariate analyses, simulation training was significantly associated with lower difficulty scores on these three tasks. Conclusion Residents who had completed Eyesi simulation training had higher confidence in performing the most difficult tasks perceived during phacoemulsification. PMID:29785084

Family enmeshment, adolescent emotional dysregulation, and the moderating role of gender.

PubMed

Kivisto, Katherine Little; Welsh, Deborah P; Darling, Nancy; Culpepper, Christi L

2015-08-01

Enmeshment plays a key role in many families' dysfunctional interactions and may be especially detrimental for adolescents. Sixty-four adolescents completed ratings of family enmeshment, perceived distress tolerance, an interpersonal challenge task, and mood ratings before and immediately after the task. Before and during the challenge task, adolescents' respiratory sinus arrhythmia (an indicator of cardiac vagal tone) was recorded. Associations were tested between adolescents' perceptions of family enmeshment and 3 aspects of adolescent emotional dysregulation. Adolescents who perceived higher family enmeshment also demonstrated greater emotional dysregulation in several domains: negative global appraisals of distress tolerance, stronger increase in subjective negative mood from baseline to postchallenge, lower baseline vagal tone, and vagal augmentation during the challenge task. Gender differences also emerged, such that girls reported more negative distress appraisals overall and enmeshed boys showed greater emotional dysregulation across analyses. Findings are discussed in terms of how clinicians may dynamically assess and treat enmeshment and emotional dysregulation in families with male and female adolescents. (c) 2015 APA, all rights reserved).

"When the going gets tough, the tough get going": Motivation towards closure and effort investment in the performance of cognitive tasks.

PubMed

Sankaran, Sindhuja; Szumowska, Ewa; Kossowska, Małgorzata

2017-01-01

Previous studies have demonstrated that the need for closure (NFC), which refers to an individual's aversion toward uncertainty and the desire to quickly reduce it, leads to reluctance to invest effort in judgments and decision making. However, we argue that NFC may lead to either an increase or a decrease in effort depending on the availability of easy vs. difficult means to achieve closure and perceived importance of the task goal. We found that when closure could be achieved via both less and more demanding means, NFC was associated with decreased effort unless the task was perceived as important (Study 1). However, when attaining closure was possible via demanding means only, NFC was associated with increased effort, regardless of the task importance (Study 2). Moreover, NFC was related to choosing a more instrumental strategy for the goal of closure, even if this strategy required effort (Study 3). The results are discussed in the light of cognitive energetics theory.

Attendance dynamics at work: the antecedents and correlates of presenteeism, absenteeism, and productivity loss.

PubMed

Johns, Gary

2011-10-01

Presenteeism is attending work when ill. This study examined the antecedents and correlates of presenteeism, absenteeism, and productivity loss attributed to presenteeism. Predictors included work context, personal characteristics, and work experiences. Business school graduates employed in a variety of work positions (N = 444) completed a Web-based survey. Presenteeism was positively associated with task significance, task interdependence, ease of replacement, and work to family conflict and negatively associated with neuroticism, equity, job security, internal health locus of control, and the perceived legitimacy of absence. Absenteeism was positively related to task significance, perceived absence legitimacy, and family to work conflict and negatively related to task interdependence and work to family conflict. Those high on neuroticism, the unconscientious, the job-insecure, those who viewed absence as more legitimate, and those experiencing work-family conflict reported more productivity loss. Overall, the results reveal the value of a behavioral approach to presenteeism over and above a strict medical model. (PsycINFO Database Record (c) 2011 APA, all rights reserved).

Development of a valid simulation assessment for a military dismounted assault task.

PubMed

Silk, Aaron J; Billing, Daniel C

2013-03-01

The Australian Defence Force is currently developing physical standards commensurate with job demands. Vital to this development process has been the accurate profiling of common military tasks. One such task required of all dismounted combat soldiers, an offensive assault on an enemy force, was the subject of in-depth profiling. In addition to overall assault performance, potential differences among patrol roles (scout, gunner, and flank) were investigated. Three different mock assaults of 100 to 150 m were performed by three patrols comprising qualified experienced infantry soldiers. Each soldier was fitted with a heart rate monitor and wore a global positioning device. Average assault duration was 6.5 minutes and required nineteen 7-m bounds performed on a 22-seconds duty cycle at 75% heart rate reserve and a work to rest ratio 1:4. Assaults conducted in more densely vegetated terrain resulted in significantly reduced (p < 0.05) bound distance, bound duration, and movement velocity. Results indicated significant performance differences (p < 0.05) among patrol roles for external load carried, heart rate response, bound duration, and distance covered while movement velocity was not different (p > 0.05). As a result of profiling the assault task, a valid simulation capable of assessing soldiers' physical capacity to perform this task was developed. Reprint & Copyright © 2013 Association of Military Surgeons of the U.S.

Early Life Manipulations Alter Learning and Memory in Rats

PubMed Central

Kosten, Therese A; Kim, Jeansok J; Lee, Hongjoo J.

2012-01-01

Much research shows early life manipulations have enduring behavioral, neural, and hormonal effects. However, findings of learning and memory performance vary widely across studies. We reviewed studies in which pre-weaning rat pups were exposed to stressors and tested on learning and memory tasks in adulthood. Tasks were classified as aversive conditioning, inhibitory learning, or spatial/relational memory. Variables of duration, type, and timing of neonatal manipulation and sex and strain of animals were examined to determine if any predict enhanced or impaired performance. Brief separations enhanced and prolonged separations impaired performance on spatial/relational tasks. Performance was impaired in aversive conditioning and enhanced in inhibitory learning tasks regardless of manipulation duration. Opposing effects on performance for spatial/relational memory also depended upon timing of manipulation. Enhanced performance was likely if the manipulation occurred during postnatal week 3 but performance was impaired if it was confined to the first two postnatal weeks. Thus, the relationship between early life experiences and adulthood learning and memory performance is multifaceted and decidedly task-dependent. PMID:22819985

Effects of stimulus order on discrimination processes in comparative and equality judgements: data and models.

PubMed

Dyjas, Oliver; Ulrich, Rolf

2014-01-01

In typical discrimination experiments, participants are presented with a constant standard and a variable comparison stimulus and their task is to judge which of these two stimuli is larger (comparative judgement). In these experiments, discrimination sensitivity depends on the temporal order of these stimuli (Type B effect) and is usually higher when the standard precedes rather than follows the comparison. Here, we outline how two models of stimulus discrimination can account for the Type B effect, namely the weighted difference model (or basic Sensation Weighting model) and the Internal Reference Model. For both models, the predicted psychometric functions for comparative judgements as well as for equality judgements, in which participants indicate whether they perceived the two stimuli to be equal or not equal, are derived and it is shown that the models also predict a Type B effect for equality judgements. In the empirical part, the models' predictions are evaluated. To this end, participants performed a duration discrimination task with comparative judgements and with equality judgements. In line with the models' predictions, a Type B effect was observed for both judgement types. In addition, a time-order error, as indicated by shifts of the psychometric functions, and differences in response times were observed only for the equality judgement. Since both models entail distinct additional predictions, it seems worthwhile for future research to unite the two models into one conceptual framework.

Time discrimination deficits in schizophrenia patients with first-rank (passivity) symptoms.

PubMed

Waters, Flavie; Jablensky, Assen

2009-05-15

Schizophrenia patients with first-rank (passivity) symptoms (FRS) report a loss of clear boundaries between the self and others and that their thoughts and actions are controlled by external forces. One of the more widely accepted explanatory models of FRS suggests a dysfunction in the 'forward model' system, whose role consists in predicting the sensory consequences of actions [Frith, C., 2006. The neural basis of hallucinations and delusions. Comptes Rendus Biologies 328, 169-175.]. There has been recent interest in the importance of timing precision underlying both the functioning of the forward model, and in processes contributing to the mechanisms of self-recognition [Haggard, P., Martin, F., Taylor-Clarke, M., Jeannerod, M., Franck, N., 2003. Awareness of action in schizophrenia. Neuroreport 14, 1081-1085.]. In the current study, we examined whether schizophrenia patients with FRS have a time perception impairment, using an auditory discrimination task requiring judgments of temporal intervals. Thirty-five schizophrenia patients (15 with, and 20 without, FRS), and 16 non-clinical controls completed the task. The results showed that patients with FRS experienced time differently by underestimating the duration of time intervals. Given the role of timing in shaping sensory awareness and in the formation of causal mental associations, a breakdown in timing mechanisms may affect the processes relating to the perceived control of actions and mental events, leading to disturbances of self-recognition in FRS.

Impact of cognitive function and dysarthria on spoken language and perceived speech severity in multiple sclerosis

NASA Astrophysics Data System (ADS)

Feenaughty, Lynda

Purpose: The current study sought to investigate the separate effects of dysarthria and cognitive status on global speech timing, speech hesitation, and linguistic complexity characteristics and how these speech behaviors impose on listener impressions for three connected speech tasks presumed to differ in cognitive-linguistic demand for four carefully defined speaker groups; 1) MS with cognitive deficits (MSCI), 2) MS with clinically diagnosed dysarthria and intact cognition (MSDYS), 3) MS without dysarthria or cognitive deficits (MS), and 4) healthy talkers (CON). The relationship between neuropsychological test scores and speech-language production and perceptual variables for speakers with cognitive deficits was also explored. Methods: 48 speakers, including 36 individuals reporting a neurological diagnosis of MS and 12 healthy talkers participated. The three MS groups and control group each contained 12 speakers (8 women and 4 men). Cognitive function was quantified using standard clinical tests of memory, information processing speed, and executive function. A standard z-score of ≤ -1.50 indicated deficits in a given cognitive domain. Three certified speech-language pathologists determined the clinical diagnosis of dysarthria for speakers with MS. Experimental speech tasks of interest included audio-recordings of an oral reading of the Grandfather passage and two spontaneous speech samples in the form of Familiar and Unfamiliar descriptive discourse. Various measures of spoken language were of interest. Suprasegmental acoustic measures included speech and articulatory rate. Linguistic speech hesitation measures included pause frequency (i.e., silent and filled pauses), mean silent pause duration, grammatical appropriateness of pauses, and interjection frequency. For the two discourse samples, three standard measures of language complexity were obtained including subordination index, inter-sentence cohesion adequacy, and lexical diversity. Ten listeners judged each speech sample using the perceptual construct of Speech Severity using a visual analog scale. Additional measures obtained to describe participants included the Sentence Intelligibility Test (SIT), the 10-item Communication Participation Item Bank (CPIB), and standard biopsychosocial measures of depression (Beck Depression Inventory-Fast Screen; BDI-FS), fatigue (Fatigue Severity Scale; FSS), and overall disease severity (Expanded Disability Status Scale; EDSS). Healthy controls completed all measures, with the exception of the CPIB and EDSS. All data were analyzed using standard, descriptive and parametric statistics. For the MSCI group, the relationship between neuropsychological test scores and speech-language variables were explored for each speech task using Pearson correlations. The relationship between neuropsychological test scores and Speech Severity also was explored. Results and Discussion: Topic familiarity for descriptive discourse did not strongly influence speech production or perceptual variables; however, results indicated predicted task-related differences for some spoken language measures. With the exception of the MSCI group, all speaker groups produced the same or slower global speech timing (i.e., speech and articulatory rates), more silent and filled pauses, more grammatical and longer silent pause durations in spontaneous discourse compared to reading aloud. Results revealed no appreciable task differences for linguistic complexity measures. Results indicated group differences for speech rate. The MSCI group produced significantly faster speech rates compared to the MSDYS group. Both the MSDYS and the MSCI groups were judged to have significantly poorer perceived Speech Severity compared to typically aging adults. The Task x Group interaction was only significant for the number of silent pauses. The MSDYS group produced fewer silent pauses in spontaneous speech and more silent pauses in the reading task compared to other groups. Finally, correlation analysis revealed moderate relationships between neuropsychological test scores and speech hesitation measures, within the MSCI group. Slower information processing and poorer memory were significantly correlated with more silent pauses and poorer executive function was associated with fewer filled pauses in the Unfamiliar discourse task. Results have both clinical and theoretical implications. Overall, clinicians should demonstrate caution when interpreting global measures of speech timing and perceptual measures in the absence of information about cognitive ability. Results also have implications for a comprehensive model of spoken language incorporating cognitive, linguistic, and motor variables.

Effects of mental tasks on the cardiorespiratory synchronization.

PubMed

Zhang, Jianbao; Yu, Xiaolin; Xie, Dongdong

2010-01-31

The cardiovascular and respiratory systems are functionally related to each other, but it is unclear if the cerebral cortex can affect their interaction. The effect of a mental task on the synchronization between cardiovascular and respiratory systems was investigated in the article. Electroencephalogram (EEG), electrocardiogram (ECG) and respiratory signal (RES) were collected from 29 healthy male subjects during the mental arithmetic (MA) task and the synchrogram was used to estimate the strength of cardiorespiratory synchronization. Our results showed that MA task significantly increased the breath rate, the heart rate and the EEG power spectral energy in theta band at FC3, FC4 and C4 electrodes (p<0.01), decreased the duration of cardiorespiratory synchronization epochs (p<0.05). Moreover the duration of cardiorespiratory synchronization epochs during MA task was negatively correlated with the EEG power spectral energy in theta band at FC3, FC4 and C4 electrodes and the sympathetic activity (p<0.05). The results demonstrated that ANS and cerebral cortex are implicated in the changes of cardiorespiratory synchronization during MA task. Copyright 2009 Elsevier B.V. All rights reserved.

Peer relationships in adolescent competitive soccer: associations to perceived motivational climate, achievement goals and perfectionism.

PubMed

Ommundsen, Yngvar; Roberts, Glyn C; Lemyre, Pierre-Nicolas; Miller, Blake W

2005-09-01

The aim of this study was to examine the relationship between the perceived motivational climate, achievement goals, perfectionism and indices of peer relationships in a sample of young male and female Norwegian soccer players. The sample consisted of 1719 experienced soccer players (1231 males, 488 females) aged 12-19 years (mean = 14.9 years) participating in the Norway Cup international youth soccer competition. The players responded to a questionnaire measuring perceived peer acceptance and quality of friendship in soccer, perceived motivational climate, achievement goals and perfectionism in soccer. Canonical correlation analyses revealed that young female players who perceived the motivational climate as predominantly mastery oriented, and who were moderately task oriented and scored negatively on maladaptive perfectionism, reported better relations with their peers in soccer. Constructive peer relations were evident in that they scored positively on companionship with their best friend in soccer; they perceived this friend as being loyal and allowing of free discussion, and they reported being socially accepted by their peers in soccer. Mirroring these findings, young male players who perceived the motivational climate as predominantly performance oriented, who had a moderately negative score on task orientation but a quite strong positive score on maladaptive perfectionism, reported negative relationships with peers in terms of these aspects. They also reported being in conflict with their best soccer friend. The findings suggest that the qualities of motivation have a systematic relationship with peer acceptance and the quality of friendship in male and female youth soccer.

The relationship between regular sports participation and vigilance in male and female adolescents.

PubMed

Ballester, Rafael; Huertas, Florentino; Yuste, Francisco Javier; Llorens, Francesc; Sanabria, Daniel

2015-01-01

The present study investigated the relationship between regular sport participation (soccer) and vigilance performance. Two groups of male and female adolescents differentiated in terms of their sport participation (athletes, n = 39, and non-athletes, n = 36) took part in the study. In one session, participants performed the Leger Multi-stage fitness test to estimate their aerobic fitness level. In the other session, participants completed the Psychomotor Vigilance Task (PVT) to evaluate their vigilance performance. Perceived arousal prior to the task and motivation toward the task were also measured in the PVT session. The results revealed that athletes had better cardiovascular fitness and showed better performance in the PVT. However, correlation analyses did not show any significant relationship between cardiovascular fitness and performance in the PVT. Athletes showed larger scores in motivation and perceived arousal measures with respect to non-athletes, although, once again, these variables were not correlated with PVT performance. Gender differences were observed only in the Leger test, with males showing greater fitness level than females. The major outcome of this research points to a positive relationship between regular sport participation and vigilance during adolescence. This relationship did not seem to be influenced by gender, perceived arousal, motivation toward the task or cardiovascular fitness. We discuss our results in terms of the different hypotheses put forward in the literature to explain the relationship between physical activity and cognitive functioning.

Future goal setting, task motivation and learning of minority and non-minority students in Dutch schools.

PubMed

Andriessen, Iris; Phalet, Karen; Lens, Willy

2006-12-01

Cross-cultural research on minority school achievement yields mixed findings on the motivational impact of future goal setting for students from disadvantaged minority groups. Relevant and recent motivational research, integrating Future Time Perspective Theory with Self-Determination Theory, has not yet been validated among minority students. To replicate across cultures the known motivational benefits of perceived instrumentality and internal regulation by distant future goals; to clarify when and how the future motivates minority students' educational performance. Participants in this study were 279 minority students (100 of Turkish and 179 of Moroccan origin) and 229 native Dutch students in Dutch secondary schools. Participants rated the importance of future goals, their perceptions of instrumentality, their task motivation and learning strategies. Dependent measures and their functional relations with future goal setting were simultaneously validated across minority and non-minority students, using structural equation modelling in multiple groups. As expected, Positive Perceived Instrumentality for the future increases task motivation and (indirectly) adaptive learning of both minority and non-minority students. But especially internally regulating future goals are strongly related to more task motivation and indirectly to more adaptive learning strategies. Our findings throw new light on the role of future goal setting in minority school careers: distant future goals enhance minority and non-minority students' motivation and learning, if students perceive positive instrumentality and if their schoolwork is internally regulated by future goals.

Paranoid thinking, cognitive bias and dangerous neighbourhoods: Implications for perception of threat and expectations of victimisation.

PubMed

Jack, Alexander; Egan, Vincent

2016-03-01

Paranoid thinking is prevalent in the non-clinical population and cognitive mechanisms of heuristic reasoning and jumping to conclusions bias contributes to its formation and maintenance. This study investigated the degree to which paranoia, perceived environmental risk, heuristic reasoning and jumping to conclusions bias (measured with the beads task) contribute to misinterpretation of neutral stimuli, and whether this informed judgements regarding vulnerability to threat and crime. It is also investigated whether impulsiveness is a confounding factor on the beads task. Two hundred participants were recruited using a snowball-sampling method for a quantitative cross-sectional study. Participants reported demographic information, three psychometric questionnaires and two experimental tasks via an online paradigm hosted by the Bristol Online Survey tool. Participants with high paranoia scores perceived their environment to be more dangerous than those with low scores. Participants with high paranoia scores also overestimated threat in neutral stimuli and had high expectations of future victimisation. Jumping to conclusions on the beads task did not predict fear of crime outcomes, but was predicted by impulsivity. Participants who demonstrated paranoid thinking were more likely to reside in perceived dangerous neighbourhoods and overestimate threat. While this could indicate a paranoid heuristic, it is a potentially rational response to prior experiences of crime and victimisation. Implications and suggestions for future research are discussed. © The Author(s) 2015.

Word Durations in Non-Native English

PubMed Central

Baker, Rachel E.; Baese-Berk, Melissa; Bonnasse-Gahot, Laurent; Kim, Midam; Van Engen, Kristin J.; Bradlow, Ann R.

2010-01-01

In this study, we compare the effects of English lexical features on word duration for native and non-native English speakers and for non-native speakers with different L1s and a range of L2 experience. We also examine whether non-native word durations lead to judgments of a stronger foreign accent. We measured word durations in English paragraphs read by 12 American English (AE), 20 Korean, and 20 Chinese speakers. We also had AE listeners rate the `accentedness' of these non-native speakers. AE speech had shorter durations, greater within-speaker word duration variance, greater reduction of function words, and less between-speaker variance than non-native speech. However, both AE and non-native speakers showed sensitivity to lexical predictability by reducing second mentions and high frequency words. Non-native speakers with more native-like word durations, greater within-speaker word duration variance, and greater function word reduction were perceived as less accented. Overall, these findings identify word duration as an important and complex feature of foreign-accented English. PMID:21516172

Sporadic frame dropping impact on quality perception

NASA Astrophysics Data System (ADS)

Pastrana-Vidal, Ricardo R.; Gicquel, Jean Charles; Colomes, Catherine; Cherifi, Hocine

2004-06-01

Over the past few years there has been an increasing interest in real time video services over packet networks. When considering quality, it is essential to quantify user perception of the received sequence. Severe motion discontinuities are one of the most common degradations in video streaming. The end-user perceives a jerky motion when the discontinuities are uniformly distributed over time and an instantaneous fluidity break is perceived when the motion loss is isolated or irregularly distributed. Bit rate adaptation techniques, transmission errors in the packet networks or restitution strategy could be the origin of this perceived jerkiness. In this paper we present a psychovisual experiment performed to quantify the effect of sporadically dropped pictures on the overall perceived quality. First, the perceptual detection thresholds of generated temporal discontinuities were measured. Then, the quality function was estimated in relation to a single frame dropping for different durations. Finally, a set of tests was performed to quantify the effect of several impairments distributed over time. We have found that the detection thresholds are content, duration and motion dependent. The assessment results show how quality is impaired by a single burst of dropped frames in a 10 sec sequence. The effect of several bursts of discarded frames, irregularly distributed over the time is also discussed.

Perceived Task-Difficulty Recognition from Log-File Information for the Use in Adaptive Intelligent Tutoring Systems

ERIC Educational Resources Information Center

Janning, Ruth; Schatten, Carlotta; Schmidt-Thieme, Lars

2016-01-01

Recognising students' emotion, affect or cognition is a relatively young field and still a challenging task in the area of intelligent tutoring systems. There are several ways to use the output of these recognition tasks within the system. The approach most often mentioned in the literature is using it for giving feedback to the students. The…

Human sensitivity to differences in the rate of auditory cue change.

PubMed

Maloff, Erin S; Grantham, D Wesley; Ashmead, Daniel H

2013-05-01

Measurement of sensitivity to differences in the rate of change of auditory signal parameters is complicated by confounds among duration, extent, and velocity of the changing signal. Dooley and Moore [(1988) J. Acoust. Soc. Am. 84(4), 1332-1337] proposed a method for measuring sensitivity to rate of change using a duration discrimination task. They reported improved duration discrimination when an additional intensity or frequency change cue was present. The current experiments were an attempt to use this method to measure sensitivity to the rate of change in intensity and spatial position. Experiment 1 investigated whether duration discrimination was enhanced when additional cues of rate of intensity change, rate of spatial position change, or both were provided. Experiment 2 determined whether participant listening experience or the testing environment influenced duration discrimination task performance. Experiment 3 assessed whether duration discrimination could be used to measure sensitivity to rates of changes in intensity and spatial position for stimuli with lower rates of change, as well as emphasizing the constancy of the velocity cue. Results of these experiments showed that duration discrimination was impaired rather than enhanced by the additional velocity cues. The findings are discussed in terms of the demands of listening to concurrent changes along multiple auditory dimensions.

Independent coding of absolute duration and distance magnitudes in the prefrontal cortex

PubMed Central

Marcos, Encarni; Tsujimoto, Satoshi

2016-01-01

The estimation of space and time can interfere with each other, and neuroimaging studies have shown overlapping activation in the parietal and prefrontal cortical areas. We used duration and distance discrimination tasks to determine whether space and time share resources in prefrontal cortex (PF) neurons. Monkeys were required to report which of two stimuli, a red circle or blue square, presented sequentially, were longer and farther, respectively, in the duration and distance tasks. In a previous study, we showed that relative duration and distance are coded by different populations of neurons and that the only common representation is related to goal coding. Here, we examined the coding of absolute duration and distance. Our results support a model of independent coding of absolute duration and distance metrics by demonstrating that not only relative magnitude but also absolute magnitude are independently coded in the PF. NEW & NOTEWORTHY Human behavioral studies have shown that spatial and duration judgments can interfere with each other. We investigated the neural representation of such magnitudes in the prefrontal cortex. We found that the two magnitudes are independently coded by prefrontal neurons. We suggest that the interference among magnitude judgments might depend on the goal rather than the perceptual resource sharing. PMID:27760814