Assured Human-Autonomy Interaction through Machine Self-Confidence

NASA Astrophysics Data System (ADS)

Aitken, Matthew

Autonomous systems employ many layers of approximations in order to operate in increasingly uncertain and unstructured environments. The complexity of these systems makes it hard for a user to understand the systems capabilities, especially if the user is not an expert. However, if autonomous systems are to be used efficiently, their users must trust them appropriately. This purpose of this work is to implement and assess an 'assurance' that an autonomous system can provide to the user to elicit appropriate trust. Specifically, the autonomous system's perception of its own capabilities is reported to the user as the self-confidence assurance. The self-confidence assurance should allow the user to more quickly and accurately assess the autonomous system's capabilities, generating appropriate trust in the autonomous system. First, this research defines self-confidence and discusses what the self-confidence assurance is attempting to communicate to the user. Then it provides a framework for computing the autonomous system's self-confidence as a function of self-confidence factors which correspond to individual elements in the autonomous system's process. In order to explore this idea, self-confidence is implemented on an autonomous system that uses a mixed observability Markov decision process model to solve a pursuit-evasion problem on a road network. The implementation of a factor assessing the goodness of the autonomy's expected performance is focused on in particular. This work highlights some of the issues and considerations in the design of appropriate metrics for the self-confidence factors, and provides the basis for future research for computing self-confidence in autonomous systems.

Diagnostic accuracy of heart-rate recovery after exercise in the assessment of diabetic cardiac autonomic neuropathy.

PubMed

Sacre, J W; Jellis, C L; Coombes, J S; Marwick, T H

2012-09-01

Poor prognosis associated with blunted post-exercise heart-rate recovery may reflect autonomic dysfunction. This study sought the accuracy of post-exercise heart-rate recovery in the diagnosis of cardiac autonomic neuropathy, which represents a serious, but often unrecognized complication of Type 2 diabetes. Clinical assessment of cardiac autonomic neuropathy and maximal treadmill exercise testing for heart-rate recovery were performed in 135 patients with Type 2 diabetes and negative exercise echocardiograms. Cardiac autonomic neuropathy was defined by abnormalities in ≥ 2 of 7 autonomic function markers, including four cardiac reflex tests and three indices of short-term (5-min) heart-rate variability. Heart-rate recovery was defined at 1-, 2- and 3-min post-exercise. Patients with cardiac autonomic neuropathy (n = 27; 20%) had lower heart-rate recovery at 1-, 2- and 3-min post-exercise (P < 0.01). Heart-rate recovery demonstrated univariate associations with autonomic function markers (r-values 0.20-0.46, P < 0.05). Area under the receiver-operating characteristic curve revealed good diagnostic performance of all heart-rate recovery parameters (range 0.80-0.83, P < 0.001). Optimal cut-offs for heart-rate recovery at 1-, 2- and 3-min post-exercise were ≤ 28 beats/min (sensitivity 93%, specificity 69%), ≤ 50 beats/min (sensitivity 96%, specificity 63%) and ≤ 52 beats/min (sensitivity 70%, specificity 84%), respectively. These criteria predicted cardiac autonomic neuropathy independently of relevant clinical and exercise test information (adjusted odds ratios 7-28, P < 0.05). Post-exercise heart-rate recovery provides an accurate diagnostic test for cardiac autonomic neuropathy in Type 2 diabetes. The high sensitivity and modest specificity suggests heart-rate recovery may be useful to screen for patients requiring clinical autonomic evaluation. © 2012 The Authors. Diabetic Medicine © 2012 Diabetes UK.

Validation of the Bulgarian version of Scales for Outcomes in Parkinson's Disease - Autonomic (SCOPA-AUT-BG).

PubMed

Mantarova, Stefka G; Velcheva, Irena V; Georgieva, Spaska O; Stambolieva, Katerina I

2013-01-01

The last twenty years have witnessed a surge of interest in the autonomic symptoms in Parkinson's disease (PD) and the possibilities to diagnose and treat them. The specialized questionnaire assessing the autonomic symptoms in Parkinson's disease (SCOPA-AUT) has been validated and available in English, Dutch and Spanish. In this study we aim at evaluating the validity, reliability and applicability of the Bulgarian version of SCOPA-AUT (SCOPA-AUT-BG). The study included 55 patients with idiopathic PD (mean age 64.4 +/- 8.9 yrs), and 40 healthy controls (mean age 58.5 +/- 9.4 yrs). Clinical severity and disease stage were assessed by United Parkinson's disease rating scale (UPRDS) and Hoen and Yahr (H&Y). Thirty-two of the PD patients completed SCOPA-AUT-BG again after a 7-day interval. Questionnaire reliability was analyzed by determining the internal consistency, homogeneity, discriminatory and construct validity and test-retest reliability. Analyses showed good internal consistency of the summary evaluation of SCOPA-AUT-BG (coefficient alpha of Cronbach = 0.79), which indicates the high reliability of the questionnaire. The lowest Cronbach's alpha coefficient (0.53) was found for the subscale "cardiovascular functions". A dominant role belongs to the subscales for gastrointestinal and urinary functions (Cronbach's Alpha > 0.7), where a significantly high correlation of PD with the UPDRS scale was observed. We found high test-retest reliability based on the responses associated with dysfunction of the gastrointestinal, urinary, thermoregulatory and pupillary autonomic systems. The correlation of the results of SCOPA-AUT-BG with UPDRS is higher than that with H&Y, and the construct validity is high except for the cardiovascular and pupillomotor functions subscales. The results of this study show that SCOPA-AUT-BG is a valid and reliable specialized questionnaire to evaluate autonomic function in patients with Parkinson's disease. Using it allows for more detailed clinical evaluation of these patients and justifies the need to refer them to specialized examination of autonomic functions.

Left atrial phasic function and heart rate variability in asymptomatic diabetic patients.

PubMed

Tadic, Marijana; Vukomanovic, Vladan; Cuspidi, Cesare; Suzic-Lazic, Jelena; Stanisavljevic, Dejana; Celic, Vera

2017-03-01

We evaluated left atrial (LA) phasic function and heart rate variability (HRV) in asymptomatic diabetic patients, and the relationship between HRV indices and LA phasic function assessed by volumes and speckle tracking imaging. This cross-sectional study included 55 asymptomatic patients with type 2 diabetes and 50 healthy controls without cardiovascular risk factors. All study subjects underwent laboratory analyses, complete two-dimensional echocardiography examination (2DE) and 24-h Holter monitoring. Maximum, minimum LA and pre-A LA volumes and volume indexes are significantly higher in diabetic patients. Total and passive LA emptying fractions (EF), representing the LA reservoir and conduit function, are significantly lower in diabetic subjects. Active LA EF, the parameter of the LA booster pump function, is compensatory increased in diabetic patients. Similar results were obtained by 2DE strain analysis. Cardiac autonomic function, assessed by HRV, is significantly deteriorated in diabetic patients. Time and frequency-domain HRV measures are significantly lower in diabetic subjects than in controls. HbA1c, LV mass index and HRV are associated with total LA EF and longitudinal LA strain independently of age, body mass index and LV diastolic function in the whole study population. LA phasic function and cardiac autonomic nervous system assessed by HRV are impacted by diabetes. HbA1c and HRV are independently associated with LA reservoir function evaluated by volumetric and strain methods in the whole study population. This study emphasizes the importance of determination of LA function and HRV as important markers of preclinical cardiac damage and autonomic function impairment in diabetic patients.

[Treatment of functional somatic syndrome with abdominal pain].

PubMed

Abe, Tetsuya; Kanbara, Kenji; Mizuno, Yasuyuki; Fukunaga, Mikihiko

2009-09-01

Functional somatic syndrome (FSS) with abdominal pain include functional gastrointestinal disorder, chronic pancreatitis, chronic pelvic pain syndrome, which generally contain autonomic dysfunction. Regarding the treatment of FSS, it is important to know about FSS for a therapist at first. Secondly, the therapist should find out physical dysfunction of patients positively, and confirm objectively the hypotheses about both peripheral and central pathophysiological mechanisms as much as possible. Heart rate variability is an easy method, and useful to assess autonomic function. After grasping the patient's explanatory model about the illness, the therapist showes the most acceptable treatment for the patient at last.

Preliminary Results of NASA's First Autonomous Formation Flying Experiment: Earth Observing-1 (EO-1)

NASA Technical Reports Server (NTRS)

Folta, David; Hawkins, Albin

2001-01-01

NASA's first autonomous formation flying mission is completing a primary goal of demonstrating an advanced technology called enhanced formation flying. To enable this technology, the Guidance, Navigation, and Control center at the Goddard Space Flight Center has implemented an autonomous universal three-axis formation flying algorithm in executive flight code onboard the New Millennium Program's (NMP) Earth Observing-1 (EO-1) spacecraft. This paper describes the mathematical background of the autonomous formation flying algorithm and the onboard design and presents the preliminary validation results of this unique system. Results from functionality assessment and autonomous maneuver control are presented as comparisons between the onboard EO-1 operational autonomous control system called AutoCon(tm), its ground-based predecessor, and a stand-alone algorithm.

Negative Social Evaluation Impairs Executive Functions in Adolescents With Excess Weight: Associations With Autonomic Responses.

PubMed

Padilla, María Moreno; Fernández-Serrano, María J; Verdejo García, Antonio; Reyes Del Paso, Gustavo A

2018-06-22

Adolescents with excess weight suffer social stress more frequently than their peers with normal weight. To examine the impact of social stress, specifically negative social evaluation, on executive functions in adolescents with excess weight. We also examined associations between subjective stress, autonomic reactivity, and executive functioning. Sixty adolescents (aged 13-18 years) classified into excess weight or normal weight groups participated. We assessed executive functioning (working memory, inhibition, and shifting) and subjective stress levels before and after the Trier Social Stress Task (TSST). The TSST was divided into two phases according to the feedback of the audience: positive and negative social evaluation. Heart rate and skin conductance were recorded. Adolescents with excess weight showed poorer executive functioning after exposure to TSST compared with adolescents with normal weight. Subjective stress and autonomic reactivity were also greater in adolescents with excess weight than adolescents with normal weight. Negative social evaluation was associated with worse executive functioning and increased autonomic reactivity in adolescents with excess weight. The findings suggest that adolescents with excess weight are more sensitive to social stress triggered by negative evaluations. Social stress elicited deterioration of executive functioning in adolescents with excess weight. Evoked increases in subjective stress and autonomic responses predicted decreased executive function. Deficits in executive skills could reduce cognitive control abilities and lead to overeating in adolescents with excess weight. Strategies to cope with social stress to prevent executive deficits could be useful to prevent future obesity in this population.

Evaluative procedures to detect, characterize, and assess the severity of diabetic neuropathy.

PubMed

Dyck, P J

1991-01-01

Minimal criteria for diabetic neuropathy need to be defined and universally applied. Standardized evaluative procedures need to be agreed and normal ranges determined from healthy volunteers. Types and stages of neuropathy should be established and assessments performed on representative populations of both Type 1 and Type 2 diabetic patients. Potential minimal criteria include absent ankle reflexes and vibratory sensation, and abnormalities of nerve conduction. However, the preferred criterion is the identification of more than two statistically defined abnormalities among symptoms and deficits, nerve conduction, quantitative sensory examination or quantitative autonomic examination. Various evaluative procedures are available. Symptoms should be assessed and scores can be assigned to neurological deficits. However, assessments of nerve conduction provide the most specific, objective, sensitive, and repeatable procedures, although these may be the least meaningful. Many techniques are available for quantitative sensory examination, but are poorly standardized and normal values are not available. For quantitative autonomic examination, tests are available for the adequacy of cardiovascular and peripheral vascular reflexes and increasingly for other autonomic functions. In any assessment of nerve function the conditions should be optimized and standardized, and stimuli defined. Specific instructions should be given and normal ranges established in healthy volunteers.

Autonomy and Relatedness in Inner-City Families of Substance Abusing Adolescents.

PubMed

Samuolis, Jessica; Hogue, Aaron; Dauber, Sarah; Liddle, Howard A

2006-01-01

This study examined parent-adolescent autonomous-relatedness functioning in inner-city, ethnic minority families of adolescents exhibiting drug abuse and related problem behaviors. Seventy-four parent-adolescent dyads completed a structured interaction task prior to the start of treatment that was coded using an established autonomous-relatedness measure. Adolescent drug use, externalizing, and internalizing behaviors were assessed. Parents and adolescents completed assessment instruments measuring parenting style and family conflict. Confirmatory factor analysis found significant differences in the underlying dimensions of parent and adolescent autonomous-relatedness in this sample versus previous samples. It was also found that autonomous-relatedness was associated with worse adolescent symptomatology and family impairment. Results based on both self-report and observational measures contribute to the understanding of key family constructs in this population and provide insight for both researchers and the treatment community.

Autonomy and Relatedness in Inner-City Families of Substance Abusing Adolescents

PubMed Central

Samuolis, Jessica; Hogue, Aaron; Dauber, Sarah; Liddle, Howard A.

2010-01-01

This study examined parent-adolescent autonomous-relatedness functioning in inner-city, ethnic minority families of adolescents exhibiting drug abuse and related problem behaviors. Seventy-four parent-adolescent dyads completed a structured interaction task prior to the start of treatment that was coded using an established autonomous-relatedness measure. Adolescent drug use, externalizing, and internalizing behaviors were assessed. Parents and adolescents completed assessment instruments measuring parenting style and family conflict. Confirmatory factor analysis found significant differences in the underlying dimensions of parent and adolescent autonomous-relatedness in this sample versus previous samples. It was also found that autonomous-relatedness was associated with worse adolescent symptomatology and family impairment. Results based on both self-report and observational measures contribute to the understanding of key family constructs in this population and provide insight for both researchers and the treatment community. PMID:20376203

Effects of work stress and home stress on autonomic nervous function in Japanese male workers

PubMed Central

MAEDA, Eri; IWATA, Toyoto; MURATA, Katsuyuki

2014-01-01

Autonomic imbalance is one of the important pathways through which psychological stress contributes to cardiovascular diseases/sudden death. Although previous studies have focused mainly on stress at work (work stress), the association between autonomic function and stress at home (home stress) is still poorly understood. The purpose was to clarify the effect of work/home stress on autonomic function in 1,809 Japanese male workers. We measured corrected QT (QTc) interval and QT index on the electrocardiogram along with blood pressure and heart rate. Participants provided self-reported information about the presence/absence of work/home stress and the possible confounders affecting QT indicators. Home stress was related positively to QT index (p=0.040) after adjusting for the possible confounders, though work stress did not show a significant relation to QTc interval or QT index. The odds ratio of home stress to elevated QT index (≥105) was 2.677 (95% CI, 1.050 to 6.822). Work/home stress showed no significant relation to blood pressure or heart rate. These findings suggest that autonomic imbalance, readily assessed by QT indicators, can be induced by home stress in Japanese workers. Additional research is needed to identify different types of home stress that are strongly associated with autonomic imbalance. PMID:25382383

Effects of work stress and home stress on autonomic nervous function in Japanese male workers.

PubMed

Maeda, Eri; Iwata, Toyoto; Murata, Katsuyuki

2015-01-01

Autonomic imbalance is one of the important pathways through which psychological stress contributes to cardiovascular diseases/sudden death. Although previous studies have focused mainly on stress at work (work stress), the association between autonomic function and stress at home (home stress) is still poorly understood. The purpose was to clarify the effect of work/home stress on autonomic function in 1,809 Japanese male workers. We measured corrected QT (QTc) interval and QT index on the electrocardiogram along with blood pressure and heart rate. Participants provided self-reported information about the presence/absence of work/home stress and the possible confounders affecting QT indicators. Home stress was related positively to QT index (p=0.040) after adjusting for the possible confounders, though work stress did not show a significant relation to QTc interval or QT index. The odds ratio of home stress to elevated QT index (≥105) was 2.677 (95% CI, 1.050 to 6.822). Work/home stress showed no significant relation to blood pressure or heart rate. These findings suggest that autonomic imbalance, readily assessed by QT indicators, can be induced by home stress in Japanese workers. Additional research is needed to identify different types of home stress that are strongly associated with autonomic imbalance.

eNOS gene haplotype is indirectly associated with the recovery of cardiovascular autonomic modulation from exercise.

PubMed

Silva, Bruno M; Barbosa, Thales C; Neves, Fabricia J; Sales, Allan K; Rocha, Natalia G; Medeiros, Renata F; Pereira, Felipe S; Garcia, Vinicius P; Cardoso, Fabiane T; Nobrega, Antonio C L

2014-12-01

Polymorphisms in the endothelial nitric oxide synthase (eNOS) gene decrease expression and activation of eNOS in vitro, which is associated with lower post-exercise increase in vasodilator reactivity in vivo. However, it is unknown whether such polymorphisms are associated with other eNOS-related phenotypes during recovery from exercise. Therefore, we investigated the impact of an eNOS haplotype containing polymorphic alleles at loci -786 and 894 on the recovery of cardiovascular autonomic function from exercise. Sedentary, non-obese, healthy subjects were enrolled [n = 107, age 32 ± 1 years (mean ± SEM)]. Resting autonomic modulation (heart rate variability, systolic blood pressure variability, and spontaneous baroreflex sensitivity) and vascular reactivity (forearm hyperemic response post-ischemia) were assessed at baseline, 10, 60, and 120 min after a maximal cardiopulmonary exercise test. Besides, autonomic function was assessed by heart rate recovery (HRR) immediately after peak exercise. Haplotype analysis showed that vagal modulation (i.e., HF n.u.) was significantly higher, combined sympathetic and vagal modulation (i.e., LF/HF) was significantly lower and total blood pressure variability was significantly lower post-exercise in a haplotype containing polymorphic alleles (H2) compared to a haplotype with wild type alleles (H1). HRR was similar between groups. Corroborating previous evidence, H2 had significantly lower post-exercise increase in vasodilator reactivity than H1. In conclusion, a haplotype containing polymorphic alleles at loci -786 and 894 had enhanced recovery of autonomic modulation from exercise, along with unchanged HRR, and attenuated vasodilator reactivity. Then, these results suggest an autonomic compensatory response of a direct deleterious effect of eNOS polymorphisms on the vascular function. Copyright © 2014 Elsevier B.V. All rights reserved.

Viewing nature scenes positively affects recovery of autonomic function following acute-mental stress.

PubMed

Brown, Daniel K; Barton, Jo L; Gladwell, Valerie F

2013-06-04

A randomized crossover study explored whether viewing different scenes prior to a stressor altered autonomic function during the recovery from the stressor. The two scenes were (a) nature (composed of trees, grass, fields) or (b) built (composed of man-made, urban scenes lacking natural characteristics) environments. Autonomic function was assessed using noninvasive techniques of heart rate variability; in particular, time domain analyses evaluated parasympathetic activity, using root-mean-square of successive differences (RMSSD). During stress, secondary cardiovascular markers (heart rate, systolic and diastolic blood pressure) showed significant increases from baseline which did not differ between the two viewing conditions. Parasympathetic activity, however, was significantly higher in recovery following the stressor in the viewing scenes of nature condition compared to viewing scenes depicting built environments (RMSSD; 50.0 ± 31.3 vs 34.8 ± 14.8 ms). Thus, viewing nature scenes prior to a stressor alters autonomic activity in the recovery period. The secondary aim was to examine autonomic function during viewing of the two scenes. Standard deviation of R-R intervals (SDRR), as change from baseline, during the first 5 min of viewing nature scenes was greater than during built scenes. Overall, this suggests that nature can elicit improvements in the recovery process following a stressor.

Viewing Nature Scenes Positively Affects Recovery of Autonomic Function Following Acute-Mental Stress

PubMed Central

2013-01-01

A randomized crossover study explored whether viewing different scenes prior to a stressor altered autonomic function during the recovery from the stressor. The two scenes were (a) nature (composed of trees, grass, fields) or (b) built (composed of man-made, urban scenes lacking natural characteristics) environments. Autonomic function was assessed using noninvasive techniques of heart rate variability; in particular, time domain analyses evaluated parasympathetic activity, using root-mean-square of successive differences (RMSSD). During stress, secondary cardiovascular markers (heart rate, systolic and diastolic blood pressure) showed significant increases from baseline which did not differ between the two viewing conditions. Parasympathetic activity, however, was significantly higher in recovery following the stressor in the viewing scenes of nature condition compared to viewing scenes depicting built environments (RMSSD; 50.0 ± 31.3 vs 34.8 ± 14.8 ms). Thus, viewing nature scenes prior to a stressor alters autonomic activity in the recovery period. The secondary aim was to examine autonomic function during viewing of the two scenes. Standard deviation of R-R intervals (SDRR), as change from baseline, during the first 5 min of viewing nature scenes was greater than during built scenes. Overall, this suggests that nature can elicit improvements in the recovery process following a stressor. PMID:23590163

PHM Enabled Autonomous Propellant Loading Operations

NASA Technical Reports Server (NTRS)

Walker, Mark; Figueroa, Fernando

2017-01-01

The utility of Prognostics and Health Management (PHM) software capability applied to Autonomous Operations (AO) remains an active research area within aerospace applications. The ability to gain insight into which assets and subsystems are functioning properly, along with the derivation of confident predictions concerning future ability, reliability, and availability, are important enablers for making sound mission planning decisions. When coupled with software that fully supports mission planning and execution, an integrated solution can be developed that leverages state assessment and estimation for the purposes of delivering autonomous operations. The authors have been applying this integrated, model-based approach to the autonomous loading of cryogenic spacecraft propellants at Kennedy Space Center.

Impact of cancer and chemotherapy on autonomic nervous system function and cardiovascular reactivity in young adults with cancer: a case-controlled feasibility study.

PubMed

Adams, Scott C; Schondorf, Ronald; Benoit, Julie; Kilgour, Robert D

2015-05-18

Preliminary evidence suggests cancer- and chemotherapy-related autonomic nervous system (ANS) dysfunction may contribute to the increased cardiovascular (CV) morbidity- and mortality-risks in cancer survivors. However, the reliability of these findings may have been jeopardized by inconsistent participant screening and assessment methods. Therefore, good laboratory practices must be established before the presence and nature of cancer-related autonomic dysfunction can be characterized. The purpose of this study was to assess the feasibility of conducting concurrent ANS and cardiovascular evaluations in young adult cancer patients, according to the following criteria: i) identifying methodological pitfalls and proposing good laboratory practice criteria for ANS testing in cancer, and ii) providing initial physiologic evidence of autonomic perturbations in cancer patients using the composite autonomic scoring scale (CASS). Thirteen patients (mixed diagnoses) were assessed immediately before and after 4 cycles of chemotherapy. Their results were compared to 12 sex- and age-matched controls. ANS function was assessed using standardized tests of resting CV (tilt-table, respiratory sinus arrhythmia and Valsalva maneuver) and sudomotor (quantitative sudomotor axon reflex test) reactivity. Cardiovascular reactivity during exercise was assessed using a modified Astrand-Ryhming cycle ergometer protocol. Our feasibility criteria addressed: i) recruitment potential, ii) retention rates, iii) pre-chemotherapy assessment potential, iv) test performance/tolerability, and v) identification and minimizing the influence of potentially confounding medication. T-tests and repeated measures ANOVAs were used to assess between- and within-group differences at baseline and follow-up. The overall success rate in achieving our feasibility criteria was 98.4 %. According to the CASS, there was evidence of ANS impairment at baseline in 30.8 % of patients, which persisted in 18.2 % of patients at follow-up, compared to 0 % of controls at baseline or follow-up. Results from our feasibility assessment suggest that the investigation of ANS function in young adult cancer patients undergoing chemotherapy is possible. To the best of our knowledge, this is the first study to report CASS-based evidence of ANS impairment and sudomotor dysfunction in any cancer population. Moreover, we provide evidence of cancer- and chemotherapy-related parasympathetic dysfunction - as a possible contributor to the pathogenesis of CV disease in cancer survivors.

Cardiac autonomic function in children with type 1 diabetes.

PubMed

Metwalley, Kotb Abbass; Hamed, Sherifa Ahmed; Farghaly, Hekma Saad

2018-06-01

Cardiovascular autonomic neuropathy (CAN) is a major complication of type 1 diabetes (T1D). This study aimed to evaluate cardiac autonomic nervous system (ANS) function in children with T1D and its relation to different demographic, clinical and laboratory variable. This cross-sectional study included 60 children with T1D (mean age = 15.1 ± 3.3 years; duration of diabetes = 7.95 ± 3.83 years). The following 8 non-invasive autonomic testing were used for evaluation: heart rate at rest and in response to active standing (30:15 ratio), deep breathing and Valsalva maneuver (indicating parasympathetic function); blood pressure response to standing (orthostatic hypotension or OH), sustained handgrip and cold; and heart rate response to standing or positional orthostatic tachycardia syndrome or POTs (indicating sympathetic function). None had clinically manifest CAN. Compared to healthy children (5%), 36.67% of children with T1D had ≥ 2 abnormal tests (i.e., CAN) (P = 0.0001) which included significantly abnormal heart rate response to standing (POTs) (P = 0.052), active standing (30:15 ratio) (P = 0.0001) and Valsalva maneuver (P = 0.0001), indicating parasympathetic autonomic dysfunction, and blood pressure response to cold (P = 0.01), indicating sympathetic autonomic dysfunction. 54.55, 27.27 and 18.18% had early, definite and severe dysfunction of ANS. All patients had sensorimotor peripheral neuropathy. The longer duration of diabetes (> 5 years), presence of diabetic complications and worse glycemic control were significantly associated with CAN. The study concluded that both parasympathetic and sympathetic autonomic dysfunctions are common in children with T1D particularly with longer duration of diabetes and presence of microvascular complications. What is Known: • Cardiovascular autonomic neuropathy (CAN) is a major complication of type 1 diabetes (T1D). • Limited studies evaluated CAN in children with T1D. What is New: • CAN is common in children with T1D. • Cardiac autonomic functions should be assessed in children with T1D particularly in presence of microvascular complications.

Feeling good: autonomic nervous system responding in five positive emotions.

PubMed

Shiota, Michelle N; Neufeld, Samantha L; Yeung, Wan H; Moser, Stephanie E; Perea, Elaine F

2011-12-01

Although dozens of studies have examined the autonomic nervous system (ANS) aspects of negative emotions, less is known about ANS responding in positive emotion. An evolutionary framework was used to define five positive emotions in terms of fitness-enhancing function, and to guide hypotheses regarding autonomic responding. In a repeated measures design, participants viewed sets of visual images eliciting these positive emotions (anticipatory enthusiasm, attachment love, nurturant love, amusement, and awe) plus an emotionally neutral state. Peripheral measures of sympathetic and vagal parasympathetic activation were assessed. Results indicated that the emotion conditions were characterized by qualitatively distinct profiles of autonomic activation, suggesting the existence of multiple, physiologically distinct positive emotions. (c) 2011 APA, all rights reserved.

Relationship between sensorimotor peripheral nerve function and indicators of cardiovascular autonomic function in older adults from the Health, Aging and Body Composition Study.

PubMed

Lange-Maia, Brittney S; Newman, Anne B; Jakicic, John M; Cauley, Jane A; Boudreau, Robert M; Schwartz, Ann V; Simonsick, Eleanor M; Satterfield, Suzanne; Vinik, Aaron I; Zivkovic, Sasa; Harris, Tamara B; Strotmeyer, Elsa S

2017-10-01

Age-related peripheral nervous system (PNS) impairments are highly prevalent in older adults. Although sensorimotor and cardiovascular autonomic function have been shown to be related in persons with diabetes, the nature of the relationship in general community-dwelling older adult populations is unknown. Health, Aging and Body Composition participants (n=2399, age=76.5±2.9years, 52% women, 38% black) underwent peripheral nerve testing at the 2000/01 clinic visit. Nerve conduction amplitude and velocity were measured at the peroneal motor nerve. Sensory nerve function was assessed with vibration detection threshold and monofilament (1.4-g/10-g) testing at the big toe. Symptoms of lower-extremity peripheral neuropathy were collected by self-report. Cardiovascular autonomic function indicators included postural hypotension, resting heart rate (HR), as well as HR response to and recovery from submaximal exercise testing (400m walk). Multivariable modeling adjusted for demographic/lifestyle factors, medication use and comorbid conditions. In fully adjusted models, poor motor nerve conduction velocity (<40m/s) was associated with greater odds of postural hypotension, (OR=1.6, 95% CI: 1.0-2.5), while poor motor amplitude (<1mV) was associated with 2.3beats/min (p=0.003) higher resting HR. No associations were observed between sensory nerve function or symptoms of peripheral neuropathy and indicators of cardiovascular autonomic function. Motor nerve function and indicators of cardiovascular autonomic function remained significantly related even after considering many potentially shared risk factors. Future studies should investigate common underlying processes for developing multiple PNS impairments in older adults. Copyright © 2017 Elsevier Inc. All rights reserved.

Effect of Sustained Human Centrifugation on Autonomic Cardiovascular and Vestibular Function

NASA Technical Reports Server (NTRS)

Schlegel, Todd T.; Wood, Scott J.; Brown, Troy E.; Benavides, Edgar W.; Harm, Deborah L.; Rupert, A. H.

2002-01-01

Repeated exposure to +Gz enhances human baroreflex responsiveness and improves tolerance to cardiovascular stress. However, both sustained exposure to +Gx and changes in otolith function resulting from the gravitational changes of space flight and parabolic flight may adversely affect autonomic cardiovascular function and orthostatic tolerance. HYPOTHESES: Baroreflex function and orthostatic tolerance are acutely improved by a single sustained (30 min) exposure to +3Gz but not +3Gx. Moreover, after 30 min of +3Gx, any changes that occur in autonomic cardiovascular function will relate commensurately to changes in otolith function. METHODS: Twenty-two healthy human subjects were first exposed to 5 min of +3 Gz centrifugation and then subsequently up to a total of30 min of either +3Gz (n = 15) or +3Gx (n = 7) centrifugation. Tests of autonomic cardiovascular function both before and after both types of centrifugation included: (a) power spectral determinations of beat-to-beat R-R intervals and arterial pressures; (b) carotid-cardiac baroreflex tests; ( c) Valsalva tests; and (d) 30-min head-up tilt (HUT) tests. Otolith function was assessed during centrifugation by the linear vestibulo-ocular reflex and both before and after centrifugation by measurements of ocular counter-rolling and dynamic posturography. RESULTS: All four +3Gz subjects who were intolerant to HUT before centrifugation became tolerant to HUT after centrifugation. The operational point of the carotid-cardiac baroreflex and the Valsalva-related baroreflex were also enhanced in the +3Gz group but not in the +3Gx group. No significant vestibular-autonomic relationships were detected, other than a significant vestibular-cerebrovascular interaction reported previously. CONCLUSIONS: A single, sustained exposure to +3 Gz centrifugation acutely improves baroreflex function and orthostatic tolerance whereas a similar exposure to +3 Gx centrifugation appears to have less effect.

Pelvic autonomic neuromonitoring: present reality, future prospects.

PubMed

Skinner, Stanley A

2014-08-01

Currently, the means to assess the autonomic nervous system primarily depend on end organ functional measurement: intravesical pressure, skin resistance, and penile strain gauge tension, for example. None of these measures has been generally accepted in the operating room. Nevertheless, the segmental and peripheral pelvic autonomic nerve supply is placed at risk during both pelvic and lower spine surgery. In this difficult era of suboptimal post-prostatectomy outcomes, the urological literature does reveal the salutary development of safer dissection techniques about the peri-prostatic and cavernous plexus. Means of reliably specific nerve identification remain elusive. The need for actual nerve monitoring (not just identification) has only recently been proposed. Data from the animal lab reinforce an appreciation of the intimate and elegant interconnectedness of autonomic and somatic structures, particularly at the segmental level. Also, the biochemistry of erectile tissue engorgement (in both sexes) is very well understood (the electrophysiology increasingly so). Understanding these principles should permit parallel investigation and implementation of neurophysiological techniques which both identify and monitor pelvic autonomic function. The predicates for these proposed new approaches in the operating room are discussed in this review.

Methods for Determining the Level of Autonomy to Design into a Human Spaceflight Vehicle: A Function Specific Approach

NASA Technical Reports Server (NTRS)

Proud, Ryan W.; Hart, Jeremy J.; Mrozinski, Richard B.

2003-01-01

The next-generation human spaceflight vehicle is in a unique position to realize the benefits of more than thirty years of technological advancements since the Space Shuttle was designed. Computer enhancements, the emergence of highly reliable decision-making algorithms, and an emphasis on efficiency make an increased use of autonomous systems highly likely. NASA is in a position to take advantage of these advances and apply them to the human spaceflight environment. One of the key paradigm shifts will be the shift, where appropriate, of monitoring, option development, decision-making, and execution responsibility from humans to an Autonomous Flight Management (AFM) system. As an effort to reduce risk for development of an AFM system, NASA engineers are developing a prototype to prove the utility of previously untested autonomy concepts. This prototype, called SMART (Spacecraft Mission Assessment and Replanning Tool), is a functionally decomposed flight management system with an appropriate level of autonomy for each of its functions. As the development of SMART began, the most important and most often asked question was, How autonomous should an AFM system be? A thorough study of the literature through 2002 surrounding autonomous systems has not yielded a standard method for designing a level of autonomy into either a crewed vehicle or an uncrewed vehicle. The current focus in the literature on defining autonomy is centered on developing IQ tests for built systems. The literature that was analyzed assumes that the goal of all systems is to strive for complete autonomy from human intervention, rather than identifying how autonomous each function within the system should have been. In contrast, the SMART team developed a method for determining the appropriate level of autonomy to be designed into each function within a system. This paper summarizes the development of the Level of Autonomy Assessment Tool and its application to the SMART project.

Cardiac autonomic function and hot flashes among perimenopausal and postmenopausal women.

PubMed

Gibson, Carolyn J; Mendes, Wendy Berry; Schembri, Michael; Grady, Deborah; Huang, Alison J

2017-07-01

Abnormalities in autonomic function are posited to play a pathophysiologic role in menopausal hot flashes. We examined relationships between resting cardiac autonomic activity and hot flashes in perimenopausal and postmenopausal women. Autonomic function was assessed at baseline and 12 weeks among perimenopausal and postmenopausal women (n = 121, mean age 53 years) in a randomized trial of slow-paced respiration for hot flashes. Pre-ejection period (PEP), a marker of sympathetic activation, was measured with impedance cardiography. Respiratory sinus arrhythmia (RSA), a marker of parasympathetic activation, was measured with electrocardiography. Participants self-reported hot flash frequency and severity in 7-day symptom diaries. Analysis of covariance models were used to relate autonomic function and hot flash frequency and severity at baseline, and to relate changes in autonomic function to changes in hot flash frequency and severity over 12 weeks, adjusting for age, body mass index, and intervention assignment. PEP was not associated with hot flash frequency or severity at baseline or over 12 weeks (P > 0.05 for all). In contrast, there was a trend toward greater frequency of moderate-to-severe hot flashes with higher RSA at baseline (β = 0.43, P = 0.06), and a positive association between change in RSA and change in frequency of moderate-to-severe hot flashes over 12 weeks (β = 0.63, P = 0.04). Among perimenopausal and postmenopausal women with hot flashes, variations in hot flash frequency and severity were not explained by variations in resting sympathetic activation. Greater parasympathetic activation was associated with more frequent moderate-to-severe hot flashes, which may reflect increased sensitivity to perceiving hot flashes.

Functional programming of the autonomic nervous system by early life immune exposure: implications for anxiety.

PubMed

Sominsky, Luba; Fuller, Erin A; Bondarenko, Evgeny; Ong, Lin Kooi; Averell, Lee; Nalivaiko, Eugene; Dunkley, Peter R; Dickson, Phillip W; Hodgson, Deborah M

2013-01-01

Neonatal exposure of rodents to an immune challenge alters a variety of behavioural and physiological parameters in adulthood. In particular, neonatal lipopolysaccharide (LPS; 0.05 mg/kg, i.p.) exposure produces robust increases in anxiety-like behaviour, accompanied by persistent changes in hypothalamic-pituitary-adrenal (HPA) axis functioning. Altered autonomic nervous system (ANS) activity is an important physiological contributor to the generation of anxiety. Here we examined the long term effects of neonatal LPS exposure on ANS function and the associated changes in neuroendocrine and behavioural indices. ANS function in Wistar rats, neonatally treated with LPS, was assessed via analysis of tyrosine hydroxylase (TH) in the adrenal glands on postnatal days (PNDs) 50 and 85, and via plethysmographic assessment of adult respiratory rate in response to mild stress (acoustic and light stimuli). Expression of genes implicated in regulation of autonomic and endocrine activity in the relevant brain areas was also examined. Neonatal LPS exposure produced an increase in TH phosphorylation and activity at both PNDs 50 and 85. In adulthood, LPS-treated rats responded with increased respiratory rates to the lower intensities of stimuli, indicative of increased autonomic arousal. These changes were associated with increases in anxiety-like behaviours and HPA axis activity, alongside altered expression of the GABA-A receptor α2 subunit, CRH receptor type 1, CRH binding protein, and glucocorticoid receptor mRNA levels in the prefrontal cortex, hippocampus and hypothalamus. The current findings suggest that in addition to the commonly reported alterations in HPA axis functioning, neonatal LPS challenge is associated with a persistent change in ANS activity, associated with, and potentially contributing to, the anxiety-like phenotype. The findings of this study reflect the importance of changes in the perinatal microbial environment on the ontogeny of physiological processes.

Functional Programming of the Autonomic Nervous System by Early Life Immune Exposure: Implications for Anxiety

PubMed Central

Sominsky, Luba; Fuller, Erin A.; Bondarenko, Evgeny; Ong, Lin Kooi; Averell, Lee; Nalivaiko, Eugene; Dunkley, Peter R.; Dickson, Phillip W.; Hodgson, Deborah M.

2013-01-01

Neonatal exposure of rodents to an immune challenge alters a variety of behavioural and physiological parameters in adulthood. In particular, neonatal lipopolysaccharide (LPS; 0.05 mg/kg, i.p.) exposure produces robust increases in anxiety-like behaviour, accompanied by persistent changes in hypothalamic-pituitary-adrenal (HPA) axis functioning. Altered autonomic nervous system (ANS) activity is an important physiological contributor to the generation of anxiety. Here we examined the long term effects of neonatal LPS exposure on ANS function and the associated changes in neuroendocrine and behavioural indices. ANS function in Wistar rats, neonatally treated with LPS, was assessed via analysis of tyrosine hydroxylase (TH) in the adrenal glands on postnatal days (PNDs) 50 and 85, and via plethysmographic assessment of adult respiratory rate in response to mild stress (acoustic and light stimuli). Expression of genes implicated in regulation of autonomic and endocrine activity in the relevant brain areas was also examined. Neonatal LPS exposure produced an increase in TH phosphorylation and activity at both PNDs 50 and 85. In adulthood, LPS-treated rats responded with increased respiratory rates to the lower intensities of stimuli, indicative of increased autonomic arousal. These changes were associated with increases in anxiety-like behaviours and HPA axis activity, alongside altered expression of the GABA-A receptor α2 subunit, CRH receptor type 1, CRH binding protein, and glucocorticoid receptor mRNA levels in the prefrontal cortex, hippocampus and hypothalamus. The current findings suggest that in addition to the commonly reported alterations in HPA axis functioning, neonatal LPS challenge is associated with a persistent change in ANS activity, associated with, and potentially contributing to, the anxiety-like phenotype. The findings of this study reflect the importance of changes in the perinatal microbial environment on the ontogeny of physiological processes. PMID:23483921

The Mediating Role of Emotional Intelligence on the Autonomic Functioning - Psychopathy Relationship.

PubMed

Ling, Shichun; Raine, Adrian; Gao, Yu; Schug, Robert

2018-06-04

Reduced autonomic activity is a risk factor for psychopathy, but the mechanisms underlying this association are under-researched. We hypothesize that emotional intelligence mediates this relationship. Emotional intelligence, cognitive intelligence, scores on the Psychopathy Checklist- Revised (PCL-R), skin conductance, and heart rate were assessed in 156 men from communities in Los Angeles. Emotional intelligence fully mediated the relationship between autonomic functioning and total psychopathy after controlling for cognitive intelligence for both autonomic measures. Full mediation was also found when using PCL-R factors and facets as outcome variables, with the exception of a partial mediation of the heart rate -Antisocial facet relationship. These findings are the first to document emotional intelligence as a mediator of the blunted physiological stress activity - psychopathy relationship, and are interpreted within the framework of the somatic marker and somatic aphasia theories of psychopathy. Possible implications for treatment interventions are also discussed. Copyright © 2018 Elsevier B.V. All rights reserved.

Future Roles for Autonomous Vertical Lift in Disaster Relief and Emergency Response

NASA Technical Reports Server (NTRS)

Young, Larry A.

2006-01-01

System analysis concepts are applied to the assessment of potential collaborative contributions of autonomous system and vertical lift (a.k.a. rotorcraft, VTOL, powered-lift, etc.) technologies to the important, and perhaps underemphasized, application domain of disaster relief and emergency response. In particular, an analytic framework is outlined whereby system design functional requirements for an application domain can be derived from defined societal good goals and objectives.

Autonomic dysfunction assessed by EZSCAN and subclinical atherosclerosis.

PubMed

Sun, Jichao; Zhang, Yinfei; Xu, Baihui; Lv, Xiaofei; Ding, Lin; Chen, Ying; Sun, Wanwan; Lu, Jieli; Xu, Min; Bi, Yufang; Ning, Guang

2014-09-01

The present study aimed to explore the association between autonomic dysfunction and measurements of atherosclerosis in a middle-aged and elderly Chinese population. A population-based cross-sectional study was performed in Shanghai, China, from March to August 2010, with 5076 participants included in the analysis. Autonomic function was assessed by a novel EZSCAN test based on sudomotor function analysis. Carotid intima-media thickness (CIMT) was measured using B-mode ultrasonography and brachial-ankle pulse wave velocity (ba-PWV) was measured using an autonomic device. Participants were divided into three groups based on EZSCAN values: Group 1: EZSCAN 0-24; Group 2, EZSCAN 25-49; and Group 3, EZSCAN 50-100. These groups denoted autonomic dysfunction risk groups as follows: no risk, moderate risk and high risk, respectively. The prevalence of elevated CIMT and ba-PWV increased markedly with increasing EZSCAN values (elevated CIMT 7.4%, 17.5%, and 29.7%, elevated ba-PWV 3.2%, 19.7%, and 36.5%, in Groups 1, 2, and 3, respectively; both Ptrend < 0.0001). Logistic regressions revealed that EZSCAN values ≥50 were associated with a non-significantly higher risk of elevated CIMT (odds ratio [OR] = 1.43; 95% confidence interval [CI] 0.98-2.07) and a significantly higher risk of elevated ba-PWV (OR = 2.16; 95% CI 1.25-3.71) compared with EZSCAN values <25, after controlling for conventional risk factors. A higher EZSCAN value (≥50), an index of high autonomic dysfunction risk, was associated with an increased risk of elevated ba-PWV and CIMT. Such associations were partially explained by traditional atherosclerotic risk factors. © 2014 Ruijin Hospital, Shanghai Jiaotong University School of Medicine and Wiley Publishing Asia Pty Ltd.

Autonomic functions in acrocyanosis assessed by heart rate variability

PubMed Central

Yılmaz, Sedat; Yokuşoğlu, Mehmet; Çınar, Muhammet; Şimşek, İsmail; Baysan, Oben; Öz, Bilgehan Savaş; Erdem, Hakan; Pay, Salih; Dinç, Ayhan

2014-01-01

Objective To evaluate the autonomic activity of patients with acrocyanosis by using heart rate variability indices. Material and Methods The study group consisted of 24 patients with acrocyanosis and the control group contained 22 sex- and age-matched healthy subjects. All subjects underwent 24-hour Holter monitoring. Among the heart rate variability (HRV) parameters, time-domain and frequency-domain indices were analysed. Results The time-domain indices of HRV indicating global autonomic functions were found to be increased, and indices indicating parasympathetic activity showed a significant decrease in the patient group. Power-spectral analysis of HRV revealed that the low frequency and high frequency power were higher in the patient group than in controls. However, the ratio of Low Frequency/High Frequency was found to be lower in the patient group than in controls. Conclusion In acrocyanosis, both sympathetic and parasympathetic systems seem to be disrupted. Therefore, we may conclude that acrocyanosis may be resulted of systemic autonomic imbalance rather than pure sympathetic over-activation. Also, these results suggest that acrocyanosis is not a localised disorder; on the contrary, it is associated with various abnormalities of the systemic autonomic nervous system. PMID:27708866

Maternal-infant interaction and autonomic function in healthy infants and infants with transposition of the great arteries.

PubMed

Harrison, Tondi M; Ferree, Allison

2014-12-01

The quality of maternal-infant interaction is a critical factor in the development of infants' autonomic function and social engagement skills. In this secondary data analysis, relationships among infant and maternal affect and behavior and quality of dyadic interaction, as measured by the Parent-Child Early Relational Assessment, and infant autonomic function, as measured by heart rate variability, were examined during feeding at 2 weeks and 2 months of age in 16 healthy infants and in 15 infants with transposition of the great arteries (TGA). Contrary to previous research, at 2 weeks infant age, mothers of infants with TGA had significantly higher scores in affect and behavior than did mothers of healthy infants. The affect and behavior and quality of dyadic interaction of infants with TGA also did not differ from that of healthy infants. Although infants' social engagement skills did not differ by health condition (TGA or healthy), these skills did differ by parasympathetic nervous system function: infants better able to suppress vagal activity with challenge had more positive and less dysregulated affect and behavior, regardless of health status. These findings suggest that maternal-infant interactions for some cardiac disease subgroups may not differ from healthy dyads. Additional research is required to identify both healthy and ill infants with delayed autonomic maturation and to develop and test interventions to enhance critical interactive functions. © 2014 Wiley Periodicals, Inc.

Cardiac autonomic neuropathy risk estimated by sudomotor function and arterial stiffness in Chinese subjects.

PubMed

Zeng, Q; Dong, S-Y; Wang, M-L; Wang, F; Li, J-M; Zhao, X-L

2016-11-01

The SUDOSCAN test was recently developed to detect diabetic autonomic neuropathy early and screen for cardiac autonomic neuropathy (CAN) through assessment of sudomotor function. The aim of this study was to investigate the relationship of cardiac autonomic dysfunction estimated by the SUDOSCAN test with arterial stiffness. A total of 4019 subjects without diabetes or established cardiovascular disease were tested with SUDOSCAN, central systolic blood pressure (cSBP) and brachial-ankle pulse wave velocity (baPWV). Hands mean electrochemical skin conductance (ESC) measured by SUDOSCAN was 70±17 μS, feet mean ESC was 71±16 μS and the CAN risk score was 21±10%. The levels of cSBP and baPWV increased across quartiles of CAN risk score (P for trend <0.001 for all). In spearman correlation analyses, the CAN risk score was positively correlated with cSBP (r=0.391, P<0.001) and baPWV (r=0.305, P<0.001). In multivariable analyses, the values of cSBP and baPWV increased 0.17 mm Hg (P=0.002) and 2.01 cm per second (P=0.010), respectively, when CAN risk score increased 1%. The results were unchanged when stratified by glucose tolerance status. In conclusion, cardiac autonomic dysfunction estimated by sudomotor function was correlated with arterial stiffness independent of conventional factors and glucose tolerance status.

Autonomic correlates at rest and during evoked attention in children with attention-deficit/hyperactivity disorder and effects of methylphenidate.

PubMed

Negrao, Bianca Lee; Bipath, Priyesh; van der Westhuizen, Deborah; Viljoen, Margaretha

2011-01-01

The aim of this study was to assess autonomic nervous system functioning in children with attention-deficit/hyperactivity disorder (ADHD) and to examine the effects of methylphenidate and focussed attention. Children with ADHD (n = 19) were tested while they were stimulant free and during a period in which they were on stimulants. On both occasions, autonomic nervous system functioning was tested at baseline and during focussed attention. Autonomic nervous system functioning of control subjects was also tested at baseline and during focussed attention. Autonomic nervous system activity was determined by means of heart rate variability (HRV) and skin conductivity analyses. Attention was evoked by means of the BioGraph Infiniti biofeedback apparatus. HRV was determined by time domain, frequency domain and Poincaré analysis of RR interval data. Skin conductivity was determined by the BioGraph Infiniti biofeedback apparatus. The main findings of this study were (a) that stimulant-free children with ADHD showed a sympathetic underarousal and parasympathetic overarousal of the sympathovagal balance relative to control subjects; (b) methylphenidate shifted the autonomic balance of children with ADHD towards normal levels; however, a normal autonomic balance was not reached, and (c) stimulant-free children with ADHD exhibited a shift in the sympathovagal balance towards the sympathetic nervous system from baseline to focussed attention; however, methylphenidate appeared to abolish this shift. Stimulant-free children with ADHD have a parasympathetic dominance of the autonomic balance, relative to control subjects. Methylphenidate attempts to restore the normal autonomic balance in children with ADHD, but inhibits the normal autonomic nervous system response to a cognitive challenge. These results indicate that methylphenidate may have a suppressive effect on the normal stress response. Although this may be of benefit to those who interact with children who suffer from ADHD, the implications for the physiological and psychological well-being of the children themselves are debatable. Further research is needed. Only 19 children with ADHD and 18 control subjects were tested. Further studies should include prior testing in order to exclude children with possible co-existing learning disabilities. Cognitive function and emotional responses of children with ADHD were not tested. © 2010 S. Karger AG, Basel.

The effect of relaxation therapy on autonomic functioning, symptoms and daily functioning, in patients with chronic fatigue syndrome or fibromyalgia: a systematic review.

PubMed

Meeus, Mira; Nijs, Jo; Vanderheiden, Tanja; Baert, Isabel; Descheemaeker, Filip; Struyf, Filip

2015-03-01

To establish the effects of relaxation therapy on autonomic function, pain, fatigue and daily functioning in patients with chronic fatigue syndrome or fibromyalgia. A systematic literature study was performed. Using specific keywords related to fibromyalgia or chronic fatigue syndrome and relaxation therapy, the electronic databases PubMed and Web of Science were searched. Included articles were assessed for their risk of bias and relevant information regarding relaxation was extracted. The review was conducted and reported according to the PRISMA-statement. Thirteen randomized clinical trials of sufficient quality were included, resulting in a total of 650 fibromyalgia patients (11 studies) and 88 chronic fatigue syndrome patients (3 studies). None of the studies reported effects on autonomic function. Six studies reported the effect of guided imagery on pain and daily functioning in fibromyalgia. The acute effect of a single session of guided imagery was studied in two studies and seems beneficial for pain relief. For other relaxation techniques (eg. muscle relaxation, autogenic training) no conclusive evidence was found for the effect on pain and functioning in fibromyalgia patients comparison to multimodal treatment programs. For fatigue a multimodal approach seemed better than relaxation, as shown in the sole three studies on chronic fatigue syndrome patients. There is moderate evidence for the acute effect of guided imagery on pain, although the content of the visualization is a matter of debate. Other relaxation formats and the effects on functionality and autonomic function require further study. © The Author(s) 2014.

Heart rate variability and heart rate turbulence in patients with polycystic ovary syndrome.

PubMed

Özkeçeci, Gülay; Ünlü, Bekir Serdar; Dursun, Hüseyin; Akçi, Önder; Köken, Gülengül; Onrat, Ersel; Avşar, Alaettin

2016-05-01

Cardiac autonomic dysfunction may develop in patients with polycystic ovary syndrome (PCOS). Heart rate variability (HRV) and heart rate turbulence (HRT) are used in assessing cardiac autonomic functions. The goal of this study was to compare the cardiac autonomic functions in patients with PCOS and healthy controls. To our knowledge, this is the first study evaluating cardiac autonomic functions in patients with PCOS with respect to both HRV and HRT. Twenty-three patients with PCOS (mean age 22.8±3.9 years) and 25 healthy female volunteers who were matched for age and body mass index (BMI) (mean age 23.5±6.2 years) were enrolled in this as case-control study. Twenty-four hour ambulatory electrocardiogram recordings of all participants were taken using Pathfinder software. The time domain parameters of HRV and HRT, including turbulence onset (TO) and turbulence slope, were calculated. Diagnosis of PCOS was made with physical and laboratory findings of hirsutism or biochemical hyperandrogenism and chronic anovulation. Diabetes mellitus, other hormon disorders or hormon therapy, pregnancy, atrial fibrilation, obesite, chronic diseases, disorders of the autonomic nervous system, a history of drug use affecting the autonomic nervous system were excluded. There were no significant differences in HRV and HRT parameters between the two groups. Cardiovascular risk factors, such as BMI, blood pressure, fasting blood glucose, and lipid parameters, were also similar. Triangular index measure of HRV was negatively correlated with high density lipoprotein cholesterol levels (r=-0.47, p<0.05), while age and BMI were significantly correlated with TO (r=0.31 and 0.47, respectively; p<0.05 for all). Cardiac autonomic functions were not found to be altered in patients with PCOS in comparison with healthy controls. These results may be explained with the absence of concomitant cardiovascular risk factors with the patients being in the early stage of the disease.

Individual Differences in Adolescents' Sympathetic and Parasympathetic Functioning Moderate Associations between Family Environment and Psychosocial Adjustment

ERIC Educational Resources Information Center

Diamond, Lisa M.; Fagundes, Christopher P.; Cribbet, Matthew R.

2012-01-01

The present study tested whether individual differences in autonomic nervous system functioning interact with environmental risk factors to predict adolescents' psychosocial functioning. The authors assessed skin conductance and respiratory sinus arrhythmia at rest and during laboratory stressors in 110 14-year-olds. Subsequently, adolescents and…

Autonomic and metabolic effects of OSA in childhood obesity.

PubMed

Oliveira, F M; Tran, W H; Lesser, D; Bhatia, R; Ortega, R; Mittelman, S D; Keens, T G; Davidson Ward, S L; Khoo, M C

2010-01-01

This study investigates the effects of exposure to intermittent hypoxia on cardiovascular autonomic control and metabolic function in obese children with obstructive sleep apnea (OSA). Each subject underwent: (1) a polysomnography; (2) morning fasting blood samples and a subsequent FSIVGTT; (3) noninvasive measurement of respiration, arterial blood pressure, and heart rate during supine and standing postures. Assessment of adiposity was performed using a DEXA scan. From these measurements, we deduced the pertinent sleep parameters, Bergman minimal model parameters and the parameters characterizing a minimal model of cardiovascular variability. Results suggest that intermittent hypoxia in OSA contributes independently to insulin resistance and autonomic dysfunction in overweight children.

The preserved autonomic functions may provide the asymptomatic clinical status in heart failure despite advanced left ventricular systolic dysfunction.

PubMed

Kocaman, Sinan Altan; Taçoy, Gülten; Ozdemir, Murat; Açıkgöz, Sadık Kadri; Cengel, Atiye

2010-12-01

Autonomic dysfunction is an important marker of prognosis in congestive heart failure (CHF) and may determine the symptoms and progression of CHF. The aim of our study was to investigate whether preserved autonomic function assessed by heart rate variability (HRV) analyses is related to absence of CHF symptoms despite prominently reduced systolic function. The study had a cross-sectional observational design. Fifty patients with left ventricular ejection fraction (EF) below 40% were enrolled. The patients were divided into two groups according to their CHF symptomatic status as Group 1 (NYHA functional class I, asymptomatic group) and Group 2 (NYHA functional class ≥ II, symptomatic group). Plasma C-reactive protein (CRP), N-terminal proB-type natriuretic peptide (NT-proBNP) levels, echocardiographic parameters and HRV indices were measured while the patients were clinically stable in each group. Possible factors associated with the development of CHF symptoms were assessed by using multiple regression analysis. Baseline clinical characteristics and left ventricular EF were similar in the two groups. Serum CRP (15 ± 21 vs 7 ± 18 mg/L, p=0.011) and NT-proBNP levels (1935 ± 1088 vs 1249 ± 1083 pg/mL, p=0.020) were significantly higher in symptomatic group. The HRV parameters (SDNN: 78 ± 57 vs 122 ± 42 ms, p=0.001; SDANN: 65 ± 55 vs 84 ± 38 ms, p=0.024; SDNNi: 36 ± 41 vs 70 ± 46 ms, p<0.001; triangular index [Ti]: 17 ± 12 vs 32 ± 14, p<0.001) were also significantly depressed in symptomatic group. When multiple regression analysis was performed, only HRV indices of autonomic function were significantly associated with the asymptomatic status (SDNN, OR: 1.016, 95%CI: 1.002-1.031, p=0.028; SDNNi, OR: 1.030, 95%CI: 1.008-1.052, p=0.006; TI, OR: 1.088, 95%CI: 1.019-1.161, p=0.011). Preserved autonomic functions were shown to be associated with absence of CHF symptoms independently of angiotensin converting enzyme inhibitor/angiotensin receptor blocker's treatment and BNP levels and may be protective against the development of CHF symptoms despite advanced left ventricular systolic dysfunction.

The relationship between erythrocyte membrane fatty acid levels and cardiac autonomic function in obese children.

PubMed

Mustafa, Gulgun; Kursat, Fidanci Muzaffer; Ahmet, Tas; Alparslan, Genc Fatih; Omer, Gunes; Sertoglu, Erdem; Erkan, Sarı; Ediz, Yesilkaya; Turker, Turker; Ayhan, Kılıc

Childhood obesity is a worldwide health concern. Studies have shown autonomic dysfunction in obese children. The exact mechanism of this dysfunction is still unknown. The aim of this study was to assess the relationship between erythrocyte membrane fatty acid (EMFA) levels and cardiac autonomic function in obese children using heart rate variability (HRV). A total of 48 obese and 32 healthy children were included in this case-control study. Anthropometric and biochemical data, HRV indices, and EMFA levels in both groups were compared statistically. HRV parameters including standard deviation of normal-to-normal R-R intervals (NN), root mean square of successive differences, the number of pairs of successive NNs that differ by >50 ms (NN50), the proportion of NN50 divided by the total number of NNs, high-frequency power, and low-frequency power were lower in obese children compared to controls, implying parasympathetic impairment. Eicosapentaenoic acid and docosahexaenoic acid levels were lower in the obese group (p<0.001 and p=0.012, respectively). In correlation analysis, in the obese group, body mass index standard deviation and linoleic acid, arachidonic acid, triglycerides, and high-density lipoprotein levels showed a linear correlation with one or more HRV parameter, and age, eicosapentaenoic acid, and systolic and diastolic blood pressure correlated with mean heart rate. In linear regression analysis, age, dihomo-gamma-linolenic acid, linoleic acid, arachidonic acid, body mass index standard deviation, systolic blood pressure, triglycerides, low-density lipoprotein and high-density lipoprotein were related to HRV parameters, implying an effect on cardiac autonomic function. There is impairment of cardiac autonomic function in obese children. It appears that levels of EMFAs such as linoleic acid, arachidonic acid and dihomo-gamma-linolenic acid play a role in the regulation of cardiac autonomic function in obese children. Copyright © 2017 Sociedade Portuguesa de Cardiologia. Publicado por Elsevier España, S.L.U. All rights reserved.

Developmental changes in autonomic emotional response during an executive functional task: A pupillometric study during Wisconsin card sorting test.

PubMed

Ohyama, Tetsuo; Kaga, Yoshimi; Goto, Yusuke; Aoyagi, Kakuro; Ishii, Sayaka; Kanemura, Hideaki; Sugita, Kanji; Aihara, Masao

2017-03-01

The autonomic nervous system has a deep relationship with the cognitive network when performing cognitive tasks. We hypothesize that autonomic emotional responses can affect cognitive function, especially executive function. The aim of this study was to clarify the involvement of the autonomic system during an executive functional task via developmental changes assessed using pupillometry. Subjects were 16 healthy children and 9 healthy adults. Children were divided into 3 groups (Group A, 7-9years; Group B, 10-14years; Group C, 15-17years). Pupil diameter was recorded using an eye mark recorder during cognitive shift (CS) during the Wisconsin card sorting test (WCST). The rate of pupil variations was integrated and compared within each group, focusing on performance during CS. Categories achieved (CA) in the behavioral results of WCST increased with age, with significant differences between Group A and other groups. The change of pupillary diameter was increased with CS and decreased at the correct answers after CS in adults. Changes of pupillary diameter with CS showed a linear increase with age, and the pattern of the pupillary response at the age of 10-14years was comparable to adults. The integrated rate of pupil diameter with CS increased with age, and there was a significant difference between Group A and adults. In addition, the degree of mydriasis correlated with the number of CA. These findings suggest that autonomic emotional response play an important role as a part of the process for executive function. Copyright © 2016 The Japanese Society of Child Neurology. Published by Elsevier B.V. All rights reserved.

Effect of 30-min +3 Gz centrifugation on vestibular and autonomic cardiovascular function

NASA Technical Reports Server (NTRS)

Schlegel, Todd T.; Wood, Scott J.; Brown, Troy E.; Harm, Deborah L.; Rupert, A. H.

2003-01-01

INTRODUCTION: Repeated exposure to increased +Gz enhances human baroreflex responsiveness and improves tolerance to cardiovascular stress. However, it is not known whether such enhancements might also result from a single, more prolonged exposure to increased +Gz. Our study was designed to investigate whether baroreflex function and orthostatic tolerance are acutely improved by a single prolonged exposure to +3 Gz, and moreover, whether changes in autonomic cardiovascular function resulting from exposure to increased +Gz are correlated with changes in otolith function. METHODS: We exposed 15 healthy human subjects to +3 Gz centrifugation for up to 30 min or until symptoms of incipient G-induced loss of consciousness (G-LOC) ensued. Tests of autonomic cardiovascular function both before and after centrifugation included: 1) power spectral determinations of beat-to-beat R-R intervals and arterial pressures; 2) carotid-cardiac baroreflex tests; 3) Valsalva tests; and 4) 30-min head-up tilt tests. Otolith function was assessed during centrifugation by the linear vestibulo-ocular reflex and both before and after centrifugation by measurements of ocular counter-rolling and dynamic posturography. RESULTS: Of the 15 subjects who underwent prolonged +3 Gz, 4 were intolerant to 30 min of head-up tilt before centrifugation but became tolerant to such tilt after centrifugation. The Valsalva-related baroreflex as well as a measure of the carotid-cardiac baroreflex were also enhanced after centrifugation. No significant vestibular-autonomic relationships were detected beyond a vestibular-cerebrovascular interaction reported earlier in a subset of seven participants. CONCLUSIONS: A single prolonged exposure to +3 Gz centrifugation acutely improves baroreflex function and orthostatic tolerance.

The autonomic laboratory

NASA Technical Reports Server (NTRS)

Low, P. A.; Opfer-Gehrking, T. L.

1999-01-01

The autonomic nervous system can now be studied quantitatively, noninvasively, and reproducibly in a clinical autonomic laboratory. The approach at the Mayo Clinic is to study the postganglionic sympathetic nerve fibers of peripheral nerve (using the quantitative sudomotor axon reflex test [QSART]), the parasympathetic nerves to the heart (cardiovagal tests), and the regulation of blood pressure by the baroreflexes (adrenergic tests). Patient preparation is extremely important, since the state of the patient influences the results of autonomic function tests. The autonomic technologist in this evolving field needs to have a solid core of knowledge of autonomic physiology and autonomic function tests, followed by training in the performance of these tests in a standardized fashion. The range and utilization of tests of autonomic function will likely continue to evolve.

Mind-wandering and alterations to default mode network connectivity when listening to naturalistic versus artificial sounds.

PubMed

Gould van Praag, Cassandra D; Garfinkel, Sarah N; Sparasci, Oliver; Mees, Alex; Philippides, Andrew O; Ware, Mark; Ottaviani, Cristina; Critchley, Hugo D

2017-03-27

Naturalistic environments have been demonstrated to promote relaxation and wellbeing. We assess opposing theoretical accounts for these effects through investigation of autonomic arousal and alterations of activation and functional connectivity within the default mode network (DMN) of the brain while participants listened to sounds from artificial and natural environments. We found no evidence for increased DMN activity in the naturalistic compared to artificial or control condition, however, seed based functional connectivity showed a shift from anterior to posterior midline functional coupling in the naturalistic condition. These changes were accompanied by an increase in peak high frequency heart rate variability, indicating an increase in parasympathetic activity in the naturalistic condition in line with the Stress Recovery Theory of nature exposure. Changes in heart rate and the peak high frequency were correlated with baseline functional connectivity within the DMN and baseline parasympathetic tone respectively, highlighting the importance of individual neural and autonomic differences in the response to nature exposure. Our findings may help explain reported health benefits of exposure to natural environments, through identification of alterations to autonomic activity and functional coupling within the DMN when listening to naturalistic sounds.

Mind-wandering and alterations to default mode network connectivity when listening to naturalistic versus artificial sounds

PubMed Central

Gould van Praag, Cassandra D.; Garfinkel, Sarah N.; Sparasci, Oliver; Mees, Alex; Philippides, Andrew O.; Ware, Mark; Ottaviani, Cristina; Critchley, Hugo D.

2017-01-01

Naturalistic environments have been demonstrated to promote relaxation and wellbeing. We assess opposing theoretical accounts for these effects through investigation of autonomic arousal and alterations of activation and functional connectivity within the default mode network (DMN) of the brain while participants listened to sounds from artificial and natural environments. We found no evidence for increased DMN activity in the naturalistic compared to artificial or control condition, however, seed based functional connectivity showed a shift from anterior to posterior midline functional coupling in the naturalistic condition. These changes were accompanied by an increase in peak high frequency heart rate variability, indicating an increase in parasympathetic activity in the naturalistic condition in line with the Stress Recovery Theory of nature exposure. Changes in heart rate and the peak high frequency were correlated with baseline functional connectivity within the DMN and baseline parasympathetic tone respectively, highlighting the importance of individual neural and autonomic differences in the response to nature exposure. Our findings may help explain reported health benefits of exposure to natural environments, through identification of alterations to autonomic activity and functional coupling within the DMN when listening to naturalistic sounds. PMID:28345604

Cardiovascular Autonomic Dysfunction in Patients with Morbid Obesity

PubMed Central

de Sant Anna Junior, Maurício; Carneiro, João Regis Ivar; Carvalhal, Renata Ferreira; Torres, Diego de Faria Magalhães; da Cruz, Gustavo Gavina; Quaresma, José Carlos do Vale; Lugon, Jocemir Ronaldo; Guimarães, Fernando Silva

2015-01-01

Background Morbid obesity is directly related to deterioration in cardiorespiratory capacity, including changes in cardiovascular autonomic modulation. Objective This study aimed to assess the cardiovascular autonomic function in morbidly obese individuals. Methods Cross-sectional study, including two groups of participants: Group I, composed by 50 morbidly obese subjects, and Group II, composed by 30 nonobese subjects. The autonomic function was assessed by heart rate variability in the time domain (standard deviation of all normal RR intervals [SDNN]; standard deviation of the normal R-R intervals [SDNN]; square root of the mean squared differences of successive R-R intervals [RMSSD]; and the percentage of interval differences of successive R-R intervals greater than 50 milliseconds [pNN50] than the adjacent interval), and in the frequency domain (high frequency [HF]; low frequency [LF]: integration of power spectral density function in high frequency and low frequency ranges respectively). Between-group comparisons were performed by the Student’s t-test, with a level of significance of 5%. Results Obese subjects had lower values of SDNN (40.0 ± 18.0 ms vs. 70.0 ± 27.8 ms; p = 0.0004), RMSSD (23.7 ± 13.0 ms vs. 40.3 ± 22.4 ms; p = 0.0030), pNN50 (14.8 ± 10.4 % vs. 25.9 ± 7.2%; p = 0.0061) and HF (30.0 ± 17.5 Hz vs. 51.7 ± 25.5 Hz; p = 0.0023) than controls. Mean LF/HF ratio was higher in Group I (5.0 ± 2.8 vs. 1.0 ± 0.9; p = 0.0189), indicating changes in the sympathovagal balance. No statistical difference in LF was observed between Group I and Group II (50.1 ± 30.2 Hz vs. 40.9 ± 23.9 Hz; p = 0.9013). Conclusion morbidly obese individuals have increased sympathetic activity and reduced parasympathetic activity, featuring cardiovascular autonomic dysfunction. PMID:26536979

Use of an allostatic neurotechnology by adolescents with postural orthostatic tachycardia syndrome (POTS) is associated with improvements in heart rate variability and changes in temporal lobe electrical activity.

PubMed

Fortunato, John E; Tegeler, Catherine L; Gerdes, Lee; Lee, Sung W; Pajewski, Nicholas M; Franco, Meghan E; Cook, Jared F; Shaltout, Hossam A; Tegeler, Charles H

2016-03-01

Autonomic dysregulation and heterogeneous symptoms characterize postural orthostatic tachycardia syndrome (POTS). This study evaluated the effect of high-resolution, relational, resonance-based, electroencephalic mirroring (HIRREM(®)), a noninvasive, allostatic neurotechnology for relaxation and auto-calibration of neural oscillations, on heart rate variability, brain asymmetry, and autonomic symptoms, in adolescents with POTS. Seven subjects with POTS (three males, ages 15-18) underwent a median of 14 (10-16) HIRREM sessions over 13 (8-17) days. Autonomic function was assessed from 10-min continuous heart rate and blood pressure recordings, pre- and post-HIRREM. One-minute epochs of temporal high-frequency (23-36 Hz) brain electrical activity data (T3 and T4, eyes closed) were analyzed from baseline HIRREM assessment and subsequent sessions. Subjects rated autonomic symptoms before and after HIRREM. Four of seven were on fludrocortisone, which was stopped before or during their sessions. Heart rate variability in the time domain (standard deviation of the beat-to-beat interval) increased post-HIRREM (mean increase 51%, range 10-143, p = 0.03), as did baroreflex sensitivity (mean increase in high-frequency alpha 65%, range -6 to 180, p = 0.05). Baseline temporal electrical asymmetry negatively correlated with change in asymmetry from assessment to the final HIRREM session (p = 0.01). Summed high-frequency amplitudes at left and right temporal lobes decreased a median of 3.8 μV (p = 0.02). There was a trend for improvements in self-reported symptoms related to the autonomic nervous system. Use of HIRREM was associated with reduced sympathetic bias in autonomic cardiovascular regulation, greater symmetry and reduced amplitudes in temporal lobe high-frequency electrical activity, and a trend for reduced autonomic symptoms. Data suggest the potential for allostatic neurotechnology to facilitate increased flexibility in autonomic cardiovascular regulation, possibly through more balanced activity at regions of the neocortex responsible for autonomic management. Clinical trial registry "Tilt Table with Suspected postural orthostatic tachycardia syndrome (POTS) Subjects," Protocol Record: WFUBAHA01.

Influence of Smoking Consumption and Nicotine Dependence Degree in Cardiac Autonomic Modulation

PubMed Central

dos Santos, Ana Paula Soares; Ramos, Dionei; de Oliveira, Gabriela Martins; dos Santos, Ana Alice Soares; Freire, Ana Paula Coelho Figueira; It, Juliana Tiyaki; Fernandes, Renato Peretti Prieto; Vanderlei, Luiz Carlos Marques; Ramos, Ercy Mara Cipulo

2016-01-01

Background Smoking consumption alters cardiac autonomic function. Objective Assess the influence of the intensity of smoking and the nicotine dependence degree in cardiac autonomic modulation evaluated through index of heart rate variability (HRV). Methods 83 smokers, of both genders, between 50 and 70 years of age and with normal lung function were divided according to the intensity of smoking consumption (moderate and severe) and the nicotine dependency degree (mild, moderate and severe). The indexes of HRV were analyzed in rest condition, in linear methods in the time domain (TD), the frequency domain (FD) and through the Poincaré plot. For the comparison of smoking consumption, unpaired t test or Mann-Whitney was employed. For the analysis between the nicotine dependency degrees, we used the One-way ANOVA test, followed by Tukey's post test or Kruskal-Wallis followed by Dunn's test. The significance level was p < 0,05. Results Differences were only found when compared to the different intensities of smoking consumption in the indexes in the FD. LFun (62.89 ± 15.24 vs 75.45 ± 10.28), which corresponds to low frequency spectrum component in normalized units; HFun (37.11 ± 15.24 vs 24.55 ± 10.28), which corresponds to high frequency spectrum component in normalized units and in the LF/HF ratio (2.21 ± 1.47 vs 4.07 ± 2.94). However, in the evaluation of nicotine dependency, significant differences were not observed (p > 0.05). Conclusion Only the intensity of smoking consumption had an influence over the cardiac autonomic modulation of the assessed tobacco smokers. Tobacco smokers with severe intensity of smoking consumption presented a lower autonomic modulation than those with moderate intensity. PMID:27142649

Simultaneous assessment of autonomic function and anxiety-related behavior in BALB/c and C57BL/6 mice.

PubMed

Depino, Amaicha Mara; Gross, Cornelius

2007-02-27

In humans, anxiety is accompanied by changes in autonomic nervous system function, including increased heart rate, body temperature, and blood pressure, and decreased heart rate variability. In rodents, anxiety is inferred by examining anxiety-related behavioral responses such as avoidance and freezing, and more infrequently by assessing autonomic responses to anxiogenic stimuli. However, few studies have simultaneously measured behavioral and autonomic responses to aversive stimuli in rodents and it remains unclear whether autonomic measures are reliable correlates of anxiety-related behavior in these animal models. Here we recorded for the first time heart rate and body temperature in freely moving BALB/c and C57BL/6 mice during exposure to an unfamiliar environment. Our data show that upon exposure to a novel open field, BALB/c mice showed increased anxiety-related behavior, reduced heart rate and higher heart rate variability (HRV) when compared with C57BL/6 mice. Regression analysis revealed a significant correlation between both heart rate and long-term HRV measures and locomotor activity and time spent in the center of the open field, but no correlation between body temperature and any behavioral variables. In the free exploration test, in which animals were allowed direct access to a novel environment from a familiar environment without experimenter handling, significant correlations were found only between heart rate and total locomotor activity, but not time spent in the unfamiliar chamber despite increased anxiety-related behavior in BALB/c mice. These findings demonstrate that increased anxiety-related behavior in BALB/c mice is not associated with specific changes in heart rate, HRV, or body temperature.

Enhanced pain and autonomic responses to ambiguous visual stimuli in chronic Complex Regional Pain Syndrome (CRPS) type I.

PubMed

Cohen, H E; Hall, J; Harris, N; McCabe, C S; Blake, D R; Jänig, W

2012-02-01

Cortical reorganisation of sensory, motor and autonomic systems can lead to dysfunctional central integrative control. This may contribute to signs and symptoms of Complex Regional Pain Syndrome (CRPS), including pain. It has been hypothesised that central neuroplastic changes may cause afferent sensory feedback conflicts and produce pain. We investigated autonomic responses produced by ambiguous visual stimuli (AVS) in CRPS, and their relationship to pain. Thirty CRPS patients with upper limb involvement and 30 age and sex matched healthy controls had sympathetic autonomic function assessed using laser Doppler flowmetry of the finger pulp at baseline and while viewing a control figure or AVS. Compared to controls, there were diminished vasoconstrictor responses and a significant difference in the ratio of response between affected and unaffected limbs (symmetry ratio) to a deep breath and viewing AVS. While viewing visual stimuli, 33.5% of patients had asymmetric vasomotor responses and all healthy controls had a homologous symmetric pattern of response. Nineteen (61%) CRPS patients had enhanced pain within seconds of viewing the AVS. All the asymmetric vasomotor responses were in this group, and were not predictable from baseline autonomic function. Ten patients had accompanying dystonic reactions in their affected limb: 50% were in the asymmetric sub-group. In conclusion, there is a group of CRPS patients that demonstrate abnormal pain networks interacting with central somatomotor and autonomic integrational pathways. © 2011 European Federation of International Association for the Study of Pain Chapters.

Utility of Autonomic Function Tests to Differentiate Dementia with Lewy Bodies and Parkinson Disease with Dementia from Alzheimer Disease.

PubMed

Toru, Shuta; Kanouchi, Tadashi; Yokota, Takanori; Yagi, Yosuke; Machida, Akira; Kobayashi, Takayoshi

2018-01-01

We studied autonomic disturbance in patients with dementia with Lewy bodies (DLB), Parkinson disease with dementia (PDD), Alzheimer disease (AD), to determine whether autonomic function tests can be used to distinguish these disorders. Autonomic function was tested in 56 patients with DLB, 37 patients with PDD, and 59 patients with AD by using the sympathetic skin response, coefficient of variation in R-R interval, the head-up tilt test, serum norepinephrine concentration, and 123I-meta-iodobenzylguanidine cardiac scintigraphy. Symptoms of autonomic dysfunction, such as constipation, urinary symptoms, and orthostatic hypotension, were also noted. The groups did not differ on baseline characteristics other than those associated with Parkinsonism and dementia. All patients with DLB and PDD had some dysautonomia, whereas rates were much lower for patients with AD (19%). Significantly more DLB and PDD patients than AD patients showed abnormalities on autonomic function tests. Autonomic function tests might be quite useful to distinguish DLB and PDD from AD. © 2017 S. Karger AG, Basel.

Effect of partition board color on mood and autonomic nervous function.

PubMed

Sakuragi, Sokichi; Sugiyama, Yoshiki

2011-12-01

The purpose of this study was to evaluate the effects of the presence or absence (control) of a partition board and its color (red, yellow, blue) on subjective mood ratings and changes in autonomic nervous system indicators induced by a video game task. The increase in the mean Profile of Mood States (POMS) Fatigue score and mean Oppressive feeling rating after the task was lowest with the blue partition board. Multiple-regression analysis identified oppressive feeling and error scores on the second half of the task as statistically significant contributors to Fatigue. While explanatory variables were limited to the physiological indices, multiple-regression analysis identified a significant contribution of autonomic reactivity (assessed by heart rate variability) to Fatigue. These results suggest that a blue partition board would reduce task-induced subjective fatigue, in part by lowering the oppressive feeling of being enclosed during the task, possibly by increasing autonomic reactivity.

Autonomous Navigation Improvements for High-Earth Orbiters Using GPS

NASA Technical Reports Server (NTRS)

Long, Anne; Kelbel, David; Lee, Taesul; Garrison, James; Carpenter, J. Russell; Bauer, F. (Technical Monitor)

2000-01-01

The Goddard Space Flight Center is currently developing autonomous navigation systems for satellites in high-Earth orbits where acquisition of the GPS signals is severely limited This paper discusses autonomous navigation improvements for high-Earth orbiters and assesses projected navigation performance for these satellites using Global Positioning System (GPS) Standard Positioning Service (SPS) measurements. Navigation performance is evaluated as a function of signal acquisition threshold, measurement errors, and dynamic modeling errors using realistic GPS signal strength and user antenna models. These analyses indicate that an autonomous navigation position accuracy of better than 30 meters root-mean-square (RMS) can be achieved for high-Earth orbiting satellites using a GPS receiver with a very stable oscillator. This accuracy improves to better than 15 meters RMS if the GPS receiver's signal acquisition threshold can be reduced by 5 dB-Hertz to track weaker signals.

Relationship between cardiac autonomic function and cognitive function in Alzheimer's disease.

PubMed

Nonogaki, Zen; Umegaki, Hiroyuki; Makino, Taeko; Suzuki, Yusuke; Kuzuya, Masafumi

2017-01-01

Alzheimer's disease (AD) affects many central nervous structures and neurotransmitter systems. These changes affect not only cognitive function, but also cardiac autonomic function. However, the functional relationship between cardiac autonomic function and cognition in AD has not yet been investigated. The objective of the present study was to evaluate the association between cardiac autonomic function measured by heart rate variability and cognitive function in AD. A total of 78 AD patients were recruited for this study. Cardiac autonomic function was evaluated using heart rate variability analysis. Multiple linear regression analysis was used to model the association between heart rate variability and cognitive function (global cognitive function, memory, executive function and processing speed), after adjustment for covariates. Global cognitive function was negatively associated with sympathetic modulation (low-to-high frequency power ratio). Memory performance was positively associated with parasympathetic modulation (high frequency power) and negatively associated with sympathetic modulation (low-to-high frequency power ratio). These associations were independent of age, sex, educational years, diabetes, hypertension and cholinesterase inhibitor use. Cognitive function, especially in the areas of memory, is associated with cardiac autonomic function in AD. Specifically, lower cognitive performance was found to be associated with significantly higher cardiac sympathetic and lower parasympathetic function in AD. Geriatr Gerontol Int 2017; 17: 92-98. © 2015 Japan Geriatrics Society.

Is vaspin related to cardio-metabolic status and autonomic function in early stages of glucose intolerance and in metabolic syndrome?

PubMed

Dimova, Rumyana; Tankova, Tsvetalina; Kirilov, Georgi; Chakarova, Nevena; Dakovska, Lilia; Grozeva, Greta

2016-01-01

This study aims to assess serum vaspin in early stages of glucose intolerance and in the presence of metabolic syndrome (MetS); and to evaluate vaspin correlation to different cardio-metabolic parameters and autonomic tone in these subjects. 185 subjects (80 males and 105 females) of mean age 45.8 ± 11.6 years and mean BMI 31.2 ± 6.3 kg/m(2), divided into groups according to: glucose tolerance, presence of MetS and cardio-vascular autonomic dysfunction (CAD), were enrolled. Glucose tolerance was studied during OGTT. Anthropometric indices, blood pressure, HbA1c, serum lipids, hsCRP, fasting immunoreactive insulin and serum vaspin were measured. Body composition was estimated by impedance analysis. AGEs were assessed by skin fluorescence. CAD was assessed by ANX-3.0. There was no difference in vaspin levels between the groups according to glucose tolerance, presence of MetS, and CAD. Regression analysis revealed independent association between serum vaspin and total body fat in newly diagnosed type 2 diabetes (NDT2D) group, and between serum vaspin and age and total body fat in MetS group. Vaspin negatively correlated with both sympathetic and parasympathetic activity in normal glucose tolerance (NGT) and just with parasympathetic tone in NGT without MetS. Our results demonstrate no overt fluctuations in vaspin levels in the early stages of glucose intolerance and in MetS. Total body fat seems to be related to vaspin levels in MetS and NDT2D. Our data show negative correlation between vaspin and autonomic function in NGT, as vaspin is associated with parasympathetic activity even in the absence of MetS.

Early determinants of vagal activity at preschool age - With potential dependence on sex.

PubMed

Kühne, Britta; Genser, Bernd; De Bock, Freia

2016-12-01

In children, autonomic nervous function is related to various highly prevalent health problems and might therefore represent an early indicator of ill health. We aimed to investigate the role of early-life exposures and physical activity (PA) as potential determinants of autonomic function at preschool age. We used an existing longitudinal data set of repeated vagal tone measurements (assessed via heart rate recovery (HRR)) and retrospectively assessed early-life exposures in 1052 children (mean age: 59.4months, 47.5% girls) from 52 preschools in Germany recruited from 2008 to 2010. HRR 1min after submaximal exercise served as primary outcome. Through multilevel linear regression analysis adjusted for demographic and socioeconomic factors, we assessed the association between repeatedly measured HRR and pregnancy smoking status, breastfeeding and objectively measured PA. Besides significant regression coefficients for previously described correlates of HRR (sex, age), we could show positive associations of HRR with breastfeeding (six versus zero months: +4.2 beats per minute (BPM), p=0.004) and PA (+1.0BPM for 10min increase of moderate-to-vigorous PA/day, p<0.001). Smoking before and during pregnancy showed no significant association with HRR in the total sample. However, we found interactions between sex and smoking before and during pregnancy as well as between sex and breastfeeding, suggesting significant associations with HRR only in girls. Besides PA, early pre- and postnatal exposures seem to have long-lasting effects on children's autonomic function, still recordable at preschool age. Our data suggest that these effects might be sex-dependent. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Neuroplus biofeedback improves attention, resilience, and injury prevention in elite soccer players.

PubMed

Rusciano, Aiace; Corradini, Giuliano; Stoianov, Ivilin

2017-06-01

Performance and injury prevention in elite soccer players are typically investigated from physical-tactical, biomechanical, and metabolic perspectives. However, executive functions, visuospatial abilities, and psychophysiological adaptability or resilience are also fundamental for efficiency and well-being in sports. Based on previous research associating autonomic flexibility with prefrontal cortical control, we designed a novel integrated autonomic biofeedback training method called Neuroplus to improve resilience, visual attention, and injury prevention. Herein, we introduce the method and provide an evaluation of 20 elite soccer players from the Italian Soccer High Division (Serie-A): 10 players trained with Neuroplus and 10 trained with a control treatment. The assessments included psychophysiological stress profiles, a visual search task, and indexes of injury prevention, which were measured pre- and posttreatment. The analysis showed a significant enhancement of physiological adaptability, recovery following stress, visual selective attention, and injury prevention that were specific to the Neuroplus group. Enhancing the interplay between autonomic and cognitive functions through biofeedback may become a key principle for obtaining excellence and well-being in sports. To our knowledge, this is the first evidence that shows improvement in visual selective attention following intense autonomic biofeedback. © 2017 Society for Psychophysiological Research.

Is applying the same exercise-based inpatient program to normal and reduced left ventricular function patients the best strategy after coronary surgery? A focus on autonomic cardiac response.

PubMed

Mendes, Renata Gonçalves; Simões, Rodrigo Polaquini; Costa, Fernando de Souza Melo; Pantoni, Camila Bianca Falasco; Di Thommazo-Luporini, Luciana; Luzzi, Sérgio; Amaral-Neto, Othon; Arena, Ross; Catai, Aparecida Maria; Borghi-Silva, Audrey

2014-01-01

To assess whether the same exercise-based inpatient program applied to patients with normal and reduced left ventricular function (LVF) evokes a similar cardiac autonomic response after coronary artery bypass graft (CABG). Forty-four patients post-CABG, subgrouped according to normal LVF [LVFN: n = 23; left ventricular ejection fraction (LVEF) ≥ 55%] and reduced LVF (LVFR: n = 21; LVEF 35-54%), were included. All initiated the exercise protocol on post-operative day 1 (PO1), following a whole progressive program until discharge. Cardiac autonomic response was assessed by the indices of heart rate variability (HRV) at rest and during exercise (extremity range of motion and ambulation). During ambulation, lower values of HRV indices were found in the LVFR group compared with the LVFN group [standard deviation of all RR (STDRR; 6.1 ± 2.7 versus 8.9 ± 4.7 ms), baseline width of the RR histogram (TINN; 30.6 ± 14.8 versus 45.8 ± 24.9 ms), SD2 (14.8 ± 8.0 versus 21.3 ± 9.0 ms), Shannon entropy (3.6 ± 0.5 versus 3.9 ± 0.4) and correlation dimension (0.08 ± 0.2 versus 0.2 ± 0.2)]. Also, when comparing the ambulation to rest change, lower values were observed in the LVFR group for linear (STDRR, TINN, RR TRI, rMSSD) and non-linear (SD2 and correlation dimension) HRV indices (p < 0.05). On PO1, we observed only intra-group differences between rest and exercise (extremity range of motion), for mean intervals between heart beats and heart rate. For patients with LVFN, the same inpatient exercise protocol triggered a more attenuated autonomic response compared with patients with LVFR. These findings have implications as to how exercise should be prescribed according to LVF in the early stages following recovery from CABG. Implications for Rehabilitation Exercise-based inpatient program, performed by post-CABG patients who have normal left ventricular function, triggered a more attenuated cardiac autonomic response compared with patients with reduced left ventricular function. Volume of the inpatient exercises should be prescribed according to the left ventricular function in the early stages following recovery from CABG.

Simultaneous fNIRS and thermal infrared imaging during cognitive task reveal autonomic correlates of prefrontal cortex activity

NASA Astrophysics Data System (ADS)

Pinti, Paola; Cardone, Daniela; Merla, Arcangelo

2015-12-01

Functional Near Infrared-Spectroscopy (fNIRS) represents a powerful tool to non-invasively study task-evoked brain activity. fNIRS assessment of cortical activity may suffer for contamination by physiological noises of different origin (e.g. heart beat, respiration, blood pressure, skin blood flow), both task-evoked and spontaneous. Spontaneous changes occur at different time scales and, even if they are not directly elicited by tasks, their amplitude may result task-modulated. In this study, concentration changes of hemoglobin were recorded over the prefrontal cortex while simultaneously recording the facial temperature variations of the participants through functional infrared thermal (fIR) imaging. fIR imaging provides touch-less estimation of the thermal expression of peripheral autonomic. Wavelet analysis revealed task-modulation of the very low frequency (VLF) components of both fNIRS and fIR signals and strong coherence between them. Our results indicate that subjective cognitive and autonomic activities are intimately linked and that the VLF component of the fNIRS signal is affected by the autonomic activity elicited by the cognitive task. Moreover, we showed that task-modulated changes in vascular tone occur both at a superficial and at larger depth in the brain. Combined use of fNIRS and fIR imaging can effectively quantify the impact of VLF autonomic activity on the fNIRS signals.

Improving Human/Autonomous System Teaming Through Linguistic Analysis

NASA Technical Reports Server (NTRS)

Meszaros, Erica L.

2016-01-01

An area of increasing interest for the next generation of aircraft is autonomy and the integration of increasingly autonomous systems into the national airspace. Such integration requires humans to work closely with autonomous systems, forming human and autonomous agent teams. The intention behind such teaming is that a team composed of both humans and autonomous agents will operate better than homogenous teams. Procedures exist for licensing pilots to operate in the national airspace system and current work is being done to define methods for validating the function of autonomous systems, however there is no method in place for assessing the interaction of these two disparate systems. Moreover, currently these systems are operated primarily by subject matter experts, limiting their use and the benefits of such teams. Providing additional information about the ongoing mission to the operator can lead to increased usability and allow for operation by non-experts. Linguistic analysis of the context of verbal communication provides insight into the intended meaning of commonly heard phrases such as "What's it doing now?" Analyzing the semantic sphere surrounding these common phrases enables the prediction of the operator's intent and allows the interface to supply the operator's desired information.

Human heart rate variability relation is unchanged during motion sickness

NASA Technical Reports Server (NTRS)

Mullen, T. J.; Berger, R. D.; Oman, C. M.; Cohen, R. J.

1998-01-01

In a study of 18 human subjects, we applied a new technique, estimation of the transfer function between instantaneous lung volume (ILV) and instantaneous heart rate (HR), to assess autonomic activity during motion sickness. Two control recordings of ILV and electrocardiogram (ECG) were made prior to the development of motion sickness. During the first, subjects were seated motionless, and during the second they were seated rotating sinusoidally about an earth vertical axis. Subjects then wore prism goggles that reverse the left-right visual field and performed manual tasks until they developed moderate motion sickness. Finally, ILV and ECG were recorded while subjects maintained a relatively constant level of sickness by intermittent eye closure during rotation with the goggles. Based on analyses of ILV to HR transfer functions from the three conditions, we were unable to demonstrate a change in autonomic control of heart rate due to rotation alone or due to motion sickness. These findings do not support the notion that moderate motion sickness is manifested as a generalized autonomic response.

Limits of clinical tests to screen autonomic function in diabetes type 1.

PubMed

Ducher, M; Bertram, D; Sagnol, I; Cerutti, C; Thivolet, C; Fauvel, J P

2001-11-01

A precocious detection of cardiac autonomic dysfunction is of major clinical interest that could lead to a more intensive supervision of diabetic patients. However, classical clinical exploration of cardiac autonomic function is not easy to undertake in a reproducible way. Thus, respective interests of autonomic nervous parameters provided by both clinical tests and computerized analysis of resting blood pressure were checked in type 1 diabetic patients without orthostatic hypotension and microalbuminuria. Thirteen diabetic subjects matched for age and gender to thirteen healthy subjects volunteered to participate to the study. From clinical tests (standing up, deep breathing, Valsalva maneuver, handgrip test), autonomic function was scored according to Ewing's methodology. Analysis of resting beat to beat blood pressure provided autonomic indices of the cardiac function (spectral analysis or Z analysis). 5 of the 13 diabetic patients exhibited a pathological score (more than one pathological response) suggesting the presence of cardiovascular autonomic dysfunction. The most discriminative test was the deep breathing test. However, spectral indices of BP recordings and baro-reflex sensitivity (BRS) of these 5 subjects were similar to those of healthy subjects and of remaining diabetic subjects. Alteration in Ewing's score given by clinical tests may not reflect an alteration of cardiac autonomic function in asymptomatic type 1 diabetic patients, because spectral indices of sympathetic and parasympathetic (including BRS) function were within normal range. Our results strongly suggest to confront results provided by both methodologies before concluding to an autonomic cardiac impairment in asymptomatic diabetic patients.

Brain metabolites in autonomic regulatory insular sites in heart failure.

PubMed

Woo, Mary A; Yadav, Santosh K; Macey, Paul M; Fonarow, Gregg C; Harper, Ronald M; Kumar, Rajesh

2014-11-15

Autonomic, pain, and neuropsychologic comorbidities appear in heart failure (HF), likely resulting from brain changes, indicated as loss of structural integrity and functional deficits. Among affected brain sites, the anterior insulae are prominent in serving major regulatory roles in many of the disrupted functions commonly seen in HF. Metabolite levels, including N-acetylaspartate (NAA), creatine (Cr), choline (Cho), and myo-inositol (MI), could indicate the nature of anterior insula tissue injury in HF. The study aim was to assess anterior insular metabolites to determine processes mediating autonomic, pain, and neuropsychologic disruptions in HF. We performed magnetic resonance spectroscopy in bilateral anterior insulae in 11 HF and 53 controls, using a 3.0-Tesla magnetic resonance imaging scanner. Peaks for NAA at 2.02 ppm, Cr at 3.02 ppm, Cho at 3.2 ppm, and MI at 3.56 ppm were assigned, peak areas were calculated, and metabolites were expressed as ratios, including NAA/Cr, Cho/Cr, and MI/Cr. HF patients showed significantly increased Cho/Cr ratios, indicative of glial proliferation or injury, on the left anterior insula, and reduced NAA/Cr levels, suggesting neuronal loss/dysfunction, on the right anterior insula over controls. No differences in MI/Cr ratios appeared between groups. Right anterior insular neuronal loss and left glial alterations may contribute to distorted autonomic, pain, and neuropsychologic functions found in HF. Copyright © 2014 Elsevier B.V. All rights reserved.

Brain Metabolites in Autonomic Regulatory Insular Sites in Heart Failure

PubMed Central

Woo, Mary A.; Yadav, Santosh K.; Macey, Paul M.; Fonarow, Gregg C.; Harper, Ronald M.; Kumar, Rajesh

2014-01-01

Autonomic, pain, and neuropsychologic comorbidities appear in heart failure (HF), likely resulting from brain changes, indicated as loss of structural integrity and functional deficits. Among affected brain sites, the anterior insulae are prominent in serving major regulatory roles in many of the disrupted functions commonly seen in HF. Metabolite levels, including N-acetylaspartate (NAA), creatine (Cr), choline (Cho), and myo-inositol (MI), could indicate the nature of anterior insula tissue injury in HF. The study aim was to assess anterior insular metabolites to determine processes mediating autonomic, pain, and neuropsychologic disruptions in HF. We performed magnetic resonance spectroscopy in bilateral anterior insulae in 11 HF and 53 controls, using a 3.0-Tesla magnetic resonance imaging scanner. Peaks for NAA at 2.02ppm, Cr at 3.02ppm, Cho at 3.2ppm, and MI at 3.56ppm were assigned, peak areas calculated, and metabolites expressed as ratios, including NAA/Cr, Cho/Cr, and MI/Cr. HF patients showed significantly increased Cho/Cr ratios, indicative of glial proliferation or injury, on the left anterior insula, and reduced NAA/Cr levels, suggesting neuronal loss/dysfunction, on the right anterior insula over controls. No differences in MI/Cr ratios appeared between groups. Right anterior insular neuronal loss and left glial alterations may contribute to distorted autonomic, pain, and neuropsychologic functions found in HF. PMID:25248953

Assessment of autonomic response by broad-band respiration

NASA Technical Reports Server (NTRS)

Berger, R. D.; Saul, J. P.; Cohen, R. J.

1989-01-01

We present a technique for introducing broad-band respiratory perturbations so that the response characteristics of the autonomic nervous system can be determined noninvasively over a wide range of physiologically relevant frequencies. A subject's respiratory bandwidth was broadened by breathing on cue to a sequence of audible tones spaced by Poisson intervals. The transfer function between the respiratory input and the resulting instantaneous heart rate was then computed using spectral analysis techniques. Results using this method are comparable to those found using traditional techniques, but are obtained with an economy of data collection.

Evaluating the autonomic nervous system in patients with laryngopharyngeal reflux.

PubMed

Huang, Wan-Ju; Shu, Chih-Hung; Chou, Kun-Ta; Wang, Yi-Fen; Hsu, Yen-Bin; Ho, Ching-Yin; Lan, Ming-Ying

2013-06-01

The pathogenesis of laryngopharyngeal reflux (LPR) remains unclear. It is linked to but distinct from gastroesophageal reflux disease (GERD), which has been shown to be related to disturbed autonomic regulation. The aim of this study is to investigate whether autonomic dysfunction also plays a role in the pathogenesis of LPR. Case-control study. Tertiary care center. Seventeen patients with LPR and 19 healthy controls, aged between 19 and 50 years, were enrolled in the study. The patients were diagnosed with LPR if they had a reflux symptom index (RSI) ≥ 13 and a reflux finding score (RFS) ≥ 7. Spectral analysis of heart rate variability (HRV) analysis was used to assess autonomic function. Anxiety and depression levels measured by the Beck Anxiety Inventory (BAI) and Beck Depression Inventory II (BDI-II) were also conducted. In HRV analysis, high frequency (HF) represents the parasympathetic activity of the autonomic nervous system, whereas low frequency (LF) represents the total autonomic activity. There were no significant differences in the LF power and HF power between the 2 groups. However, significantly lower HF% (P = .003) and a higher LF/HF ratio (P = .012) were found in patients with LPR, who demonstrated poor autonomic modulation and higher sympathetic activity. Anxiety was also frequently observed in the patient group. The study suggests that autonomic dysfunction seems to be involved in the pathogenesis of LPR. The potential beneficial effect of autonomic nervous system modulation as a therapeutic modality for LPR merits further investigation.

Clinical and electrophysiologic attributes as predictors of results of autonomic function tests

NASA Technical Reports Server (NTRS)

Wu, C. L.; Denq, J. C.; Harper, C. M.; O'Brien, P. C.; Low, P. A.

1998-01-01

Autonomic dysfunction is a feature of some neuropathies and not others. It has been suggested that some clinical and electrophysiologic attributes are predictable of autonomic impairment detected using laboratory testing; however, dear guidelines are unavailable. We evaluated 138 relatively unselected patients with peripheral neuropathy who underwent neurologic evaluation, electromyography (EMG), nerve conduction studies, and autonomic function tests to determine which variables were predictive of laboratory findings of autonomic failure. The variables evaluated were 1) clinical somatic neuropathic findings, 2) clinical autonomic symptoms, and 3) electrophysiologic findings. Autonomic symptoms were strongly predictive (Rs = 0.40, p < 0.001) of autonomic failure. Among the non-autonomic indices, absent ankle reflexes were mildly predictive (Rs = 0.19, p = 0.022) of autonomic impairment, but all others were not (duration, clinical pattern, severity, weakness, sensory loss). Electrophysiologic changes of an axonal neuropathy predicted autonomic impairment while demyelinating neuropathy did not. We conclude that autonomic studies will most likely be abnormal in patients who have symptoms of autonomic involvement and those who have an axonal neuropathy.

Terrain Navigation Concepts for Autonomous Vehicles,

DTIC Science & Technology

1984-06-01

AD-fi144 994 TERRAIN NAVIGATION CONCEPTS FOR AUTONOMOUS VEHICLES (U) i/i I ARMY ENGINEER OPOGRAPHIC LABS FORT BELVOIR VA R D LEIGHTY JUN 84 ETL-R@65...FUNCTIONS The pacing problem for developing autonomous vehicles that can efficiently move to designated locations in the real world in the perfor- mance...autonomous functions can serve as general terrain navigation requirements for our discussion of autonomous vehicles . LEIGHTY Can we build a vehicular system

Conditions for Fully Autonomous Anticipation

NASA Astrophysics Data System (ADS)

Collier, John

2006-06-01

Anticipation allows a system to adapt to conditions that have not yet come to be, either externally to the system or internally. Autonomous systems actively control the conditions of their own existence so as to increase their overall viability. This paper will first give minimal necessary and sufficient conditions for autonomous anticipation, followed by a taxonomy of autonomous anticipation. In more complex systems, there can be semi-autonomous subsystems that can anticipate and adapt on their own. Such subsystems can be integrated into a system's overall autonomy, typically with greater efficiency due to modularity and specialization of function. However, it is also possible that semi-autonomous subsystems can act against the viability of the overall system, and have their own functions that conflict with overall system functions.

Overview of the Autonomic Nervous System

MedlinePlus

... be reversible or progressive. Anatomy of the autonomic nervous system The autonomic nervous system is the part of ... organs they connect with. Function of the autonomic nervous system The autonomic nervous system controls internal body processes ...

An ambulatory recording system for the assessment of autonomic changes across multiple days

NASA Astrophysics Data System (ADS)

Sollers, John J., III; Yonezawa, Yoshiharu; Silver, Rebecca A.; Merritt, Marcellus M.; Thayer, Julian F.

2005-05-01

Recent evidence indicates that poor autonomic regulation, indexed by decreased heart period variability (HPV), is associated with decreased working memory. HPV analyses are computed on the interbeat interval time series derived from the electrocardiogram (EKG). Unfortunately, the duration of the data collection and the issue of the size of ambulatory monitors with sufficient storage capacity for multi-day records is somewhat problematic. In the present paper we describe a system that allows for the collection of large amounts of high quality data using a small data collection device. The recording system consists of a miniature, single-module electrocardiogram-recording device. This module consists of an integrated three-electrode device that is attached to the chest of the subject. A low power 8-bit micro-controller detects the R-spike and stores the time between R-spikes in milliseconds on a 512 KB EEPROM. This system can record continuously for over four days. This system will allow the recording of cardio-dynamics in the field and provide highly reliable data across multiple days. The use of this device to assess physiological function in military operations would allow researchers to examine longer data records across several contexts and to understand the role of changes in autonomic function as they relate to performance.

Predicting athletes' functional and dysfunctional emotions: The role of the motivational climate and motivation regulations.

PubMed

Ruiz, Montse C; Haapanen, Saara; Tolvanen, Asko; Robazza, Claudio; Duda, Joan L

2017-08-01

This study examined the relationships between perceptions of the motivational climate, motivation regulations, and the intensity and functionality levels of athletes' pleasant and unpleasant emotional states. Specifically, we examined the hypothesised mediational role of motivation regulations in the climate-emotion relationship. We also tested a sequence in which emotions were assumed to be predicted by the motivational climate dimensions and then served as antecedents to variability in motivation regulations. Participants (N = 494) completed a multi-section questionnaire assessing targeted variables. Structural equation modelling (SEM) revealed that a perceived task-involving climate was a positive predictor of autonomous motivation and of the impact of functional anger, and a negative predictor of the intensity of anxiety and dysfunctional anger. Autonomous motivation was a partial mediator of perceptions of a task-involving climate and the impact of functional anger. An ego-involving climate was a positive predictor of controlled motivation, and of the intensity and impact of functional anger and the intensity of dysfunctional anger. Controlled motivation partially mediated the relationship between an ego-involving climate and the intensity of dysfunctional anger. Good fit to the data also emerged for the motivational climate, emotional states, and motivation regulations sequence. Findings provide support for the consideration of hedonic tone and functionality distinctions in the assessment of athletes' emotional states.

Linear and Nonlinear Analyses of the Cardiac Autonomic Control in Children With Developmental Coordination Disorder: A Case-Control Study.

PubMed

Cavalcante Neto, Jorge L; Zamunér, Antonio R; Moreno, Bianca C; Silva, Ester; Tudella, Eloisa

2018-01-01

Children with Developmental Coordination Disorder (DCD) and children at risk for DCD (r-DCD) present motor impairments interfering in their school, leisure and daily activities. In addition, these children may have abnormalities in their cardiac autonomic control, which together with their motor impairments, restrict their health and functionality. Therefore, this study aimed to assess the cardiac autonomic control, by linear and nonlinear analysis, at supine and during an orthostatic stimulus in DCD, r-DCD and typically developed children. Thirteen DCD children (11 boys and 2 girls, aged 8.08 ± 0.79 years), 19 children at risk for DCD (13 boys and 6 girls, aged 8.10 ± 0.96 years) and 18 typically developed children, who constituted the control group (CG) (10 boys and 8 girls, aged 8.50 ± 0.96 years) underwent a heart rate variability (HRV) examination. R-R intervals were recorded in order to assess the cardiac autonomic control using a validated HR monitor. HRV was analyzed by linear and nonlinear methods and compared between r-DCD, DCD, and CG. The DCD group presented blunted cardiac autonomic adjustment to the orthostatic stimulus, which was not observed in r-DCD and CG. Regarding nonlinear analysis of HRV, the DCD group presented lower parasympathetic modulation in the supine position compared to the r-DCD and CG groups. In the within group analysis, only the DCD group did not increase HR from supine to standing posture. Symbolic analysis revealed a significant decrease in 2LV ( p < 0.0001) and 2UV ( p < 0.0001) indices from supine to orthostatic posture only in the CG. In conclusion, r-DCD and DCD children present cardiac autonomic dysfunction characterized by higher sympathetic, lower parasympathetic and lower complexity of cardiac autonomic control in the supine position, as well as a blunted autonomic adjustment to the orthostatic stimulus. Therefore, cardiovascular health improvement should be part of DCD children's management, even in cases of less severe motor impairment.

Physiological and psychological individual differences influence resting brain function measured by ASL perfusion.

PubMed

Kano, M; Coen, S J; Farmer, A D; Aziz, Q; Williams, S C R; Alsop, D C; Fukudo, S; O'Gorman, R L

2014-09-01

Effects of physiological and/or psychological inter-individual differences on the resting brain state have not been fully established. The present study investigated the effects of individual differences in basal autonomic tone and positive and negative personality dimensions on resting brain activity. Whole-brain resting cerebral perfusion images were acquired from 32 healthy subjects (16 males) using arterial spin labeling perfusion MRI. Neuroticism and extraversion were assessed with the Eysenck Personality Questionnaire-Revised. Resting autonomic activity was assessed using a validated measure of baseline cardiac vagal tone (CVT) in each individual. Potential associations between the perfusion data and individual CVT (27 subjects) and personality score (28 subjects) were tested at the level of voxel clusters by fitting a multiple regression model at each intracerebral voxel. Greater baseline perfusion in the dorsal anterior cingulate cortex (ACC) and cerebellum was associated with lower CVT. At a corrected significance threshold of p < 0.01, strong positive correlations were observed between extraversion and resting brain perfusion in the right caudate, brain stem, and cingulate gyrus. Significant negative correlations between neuroticism and regional cerebral perfusion were identified in the left amygdala, bilateral insula, ACC, and orbitofrontal cortex. These results suggest that individual autonomic tone and psychological variability influence resting brain activity in brain regions, previously shown to be associated with autonomic arousal (dorsal ACC) and personality traits (amygdala, caudate, etc.) during active task processing. The resting brain state may therefore need to be taken into account when interpreting the neurobiology of individual differences in structural and functional brain activity.

Glibenclamide treatment blocks metabolic dysfunctions and improves vagal activity in monosodium glutamate-obese male rats.

PubMed

Franco, Claudinéia C S; Prates, Kelly V; Previate, Carina; Moraes, Ana M P; Matiusso, Camila C I; Miranda, Rosiane A; de Oliveira, Júlio C; Tófolo, Laize P; Martins, Isabela P; Barella, Luiz F; Ribeiro, Tatiane A; Malta, Ananda; Pavanello, Audrei; Francisco, Flávio A; Gomes, Rodrigo M; Alves, Vander S; Moreira, Veridiana M; Rigo, Késia P; Almeida, Douglas L; de Sant Anna, Juliane R; Prado, Marialba A A C; Mathias, Paulo C F

2017-05-01

Autonomic nervous system imbalance is associated with metabolic diseases, including diabetes. Glibenclamide is an antidiabetic drug that acts by stimulating insulin secretion from pancreatic beta cells and is widely used in the treatment of type 2 diabetes. Since there is scarce data concerning autonomic nervous system activity and diabetes, the aim of this work was to test whether glibenclamide can improve autonomic nervous system activity and muscarinic acetylcholine receptor function in pre-diabetic obese male rats. Pre-diabetes was induced by treatment with monosodium L-glutamate in neonatal rats. The monosodium L-glutamate group was treated with glibenclamide (2 mg/kg body weight /day) from weaning to 100 days of age, and the control group was treated with water. Body weight, food intake, Lee index, fasting glucose, insulin levels, homeostasis model assessment of insulin resistance, omeostasis model assessment of β-cell function, and fat tissue accumulation were measured. The vagus and sympathetic nerve electrical activity were recorded. Insulin secretion was measured in isolated islets challenged with glucose, acetylcholine, and the selective muscarinic acetylcholine receptor antagonists by radioimmunoassay technique. Glibenclamide treatment prevented the onset of obesity and diminished the retroperitoneal (18%) and epididymal (25%) fat pad tissues. In addition, the glibenclamide treatment also reduced the parasympathetic activity by 28% and glycemia by 20% in monosodium L-glutamate-treated rats. The insulinotropic effect and unaltered cholinergic actions in islets from monosodium L-glutamate groups were increased. Early glibenclamide treatment prevents monosodium L-glutamate-induced obesity onset by balancing autonomic nervous system activity.

A deletion in the alpha2B-adrenergic receptor gene and autonomic nervous function in central obesity.

PubMed

Sivenius, Katariina; Niskanen, Leo; Laakso, Markku; Uusitupa, Matti

2003-08-01

We investigated the impact of a three-amino acid deletion (12Glu9) polymorphism in the alpha(2B)-adrenergic receptor gene on autonomic nervous function. The short form (Glu(9)/Glu(9)) of the polymorphism has previously been associated with a reduced basal metabolic rate in obese subjects. Because autonomic nervous function participates in the regulation of energy metabolism, there could be a link between this polymorphism and autonomic nervous function. Data of a 10-year follow-up study with 126 nondiabetic control subjects and 84 type 2 diabetic patients were used to determine the effects of the 12Glu9 polymorphism on autonomic nervous function. A deep breathing test and an orthostatic test were used to investigate parasympathetic and sympathetic autonomic nervous function. In addition, cardiovascular autonomic function was studied using power spectral analysis of heart rate variability. No significant differences were found in the frequency of the 12Glu9 deletion polymorphism between nondiabetic and diabetic subjects. The nondiabetic men with the Glu(9)/Glu(9) genotype, especially those with abdominal obesity, had significantly lower total and low-frequency power values in the power spectral analysis when compared with other men. Furthermore, in a longitudinal analysis of 10 years, the decrease in parasympathetic function was greater in nondiabetic men with the Glu(9)/Glu(9) genotype than in the men with the Glu(9)/Glu(12) or Glu(12)/Glu(12) genotypes. The results of the present study suggest that the 12Glu9 polymorphism of the alpha(2B)-adrenergic receptor gene modulates autonomic nervous function in Finnish nondiabetic men. In the nondiabetic men with the Glu(9)/Glu(9) genotype, the general autonomic tone is depressed, and vagal activity especially becomes impaired with time. Furthermore, this association is accentuated by central obesity.

Effect of Methamphetamine Dependence on Heart Rate Variability

PubMed Central

Henry, Brook L.; Minassian, Arpi; Perry, William

2010-01-01

Background Methamphetamine (METH) is an increasing popular and highly addictive stimulant associated with autonomic nervous system (ANS) dysfunction, cardiovascular pathology, and neurotoxicity. Heart rate variability (HRV) has been used to assess autonomic function and predict mortality in cardiac disorders and drug intoxication, but has not been characterized in METH use. We recorded HRV in a sample of currently abstinent individuals with a history of METH dependence compared to age- and gender-matched drug-free comparison subjects. Method HRV was assessed using time domain, frequency domain, and nonlinear entropic analyses in 17 previously METH-dependent and 21 drug-free comparison individuals during a 5 minute rest period. Results The METH-dependent group demonstrated significant reduction in HRV, reduced parasympathetic activity, and diminished heartbeat complexity relative to comparison participants. More recent METH use was associated with increased sympathetic tone. Conclusion Chronic METH exposure may be associated with decreased HRV, impaired vagal function, and reduction in heart rate complexity as assessed by multiple methods of analysis. We discuss and review evidence that impaired HRV may be related to the cardiotoxic or neurotoxic effects of prolonged METH use. PMID:21182570

Systems, methods and apparatus for quiesence of autonomic safety devices with self action

NASA Technical Reports Server (NTRS)

Hinchey, Michael G. (Inventor); Sterritt, Roy (Inventor)

2011-01-01

Systems, methods and apparatus are provided through which in some embodiments an autonomic environmental safety device may be quiesced. In at least one embodiment, a method for managing an autonomic safety device, such as a smoke detector, based on functioning state and operating status of the autonomic safety device includes processing received signals from the autonomic safety device to obtain an analysis of the condition of the autonomic safety device, generating one or more stay-awake signals based on the functioning status and the operating state of the autonomic safety device, transmitting the stay-awake signal, transmitting self health/urgency data, and transmitting environment health/urgency data. A quiesce component of an autonomic safety device can render the autonomic safety device inactive for a specific amount of time or until a challenging situation has passed.

Autonomous multifunctional nanobrushes-autonomous materials

NASA Astrophysics Data System (ADS)

Ghasemi-Nejhad, Mehrdad N.; Tius, Marcus A.

2007-04-01

In this work, taking advantage of carbon nanotubes' small size, and exceptional mechanical, chemical and electrical properties, we report on a series of nano-synthesis procedures that combine conventional chemical vapor deposition and selective substrate area growth followed by chemical functionalizations to fabricate functionalized nano-brushes from aligned carbon nanotube arrays and chemically selective functional groups. The high aspect ratio and small dimension, mechanical stability and flexibility, surface chemical and adhesive characteristics of carbon nanotubes provide opportunities to create nano-brushes with selected chemical functionalities. The nano-brushes are made from aligned multi-walled carbon nanotube bristles grafted onto long SiC fiber handles in various configurations and functionalized with various chemical functional groups. These nano-brushes can easily be manipulated physically, either manually or with the aid of motors. Here, we explain the autonomous characteristics of the functionalized nano-brushes employing functional chemical groups such that the nano-brush can potentially collect various metal particles, ions, and contaminants from liquid solutions and the air environment, autonomously. These functionalized multiwalled carbon nanotube based nano-brushes can work swiftly in both liquid and air environments. With surface modification and functionalization, the nanotube nano-brushes can potentially become a versatile nano-devices in many chemical and biological applications, where they can autonomously pick up the particles they encounter since they can be chemically programmed to function as Autonomous Chemical Nano Robots (ACNR).

Autonomic function responses to training: Correlation with body composition changes.

PubMed

Tian, Ye; Huang, Chuanye; He, Zihong; Hong, Ping; Zhao, Jiexiu

2015-11-01

The causal relation between autonomic function and adiposity is an unresolved issue. Thus, we studied whether resting heart rate variability (HRV) changes could be used to predict changes in body composition after 16 weeks of individualized exercise training. A total of 117 sedentary overweight/obese adults volunteered to join an intervention group (IN, n=82) or a control group (CON, n=35). The intervention group trained for 30-40 min three times a week with an intensity of 85-100% of individual ventilatory threshold (Thvent). At baseline and after a 16-week training period, resting HRV variables, body composition and peak oxygen uptake (VO2peak) were assessed. Compared with CON, exercise training significantly improved HRV and body composition and increased VO2peak (P<0.05). Significant correlations were observed between changes of HRV variables and body composition indices and VO2peak (P<0.05). Greater individual changes in HRV in response to exercise training were observed for those with greater total and central fat loss. Individual aerobic-based exercise training was for improving autonomic function and resting HRV responses to aerobic training is a potential indicator for adaptations to exercise training. Copyright © 2015. Published by Elsevier Inc.

Differential responses of autonomic function in sea level residents, acclimatized lowlanders at >3500 m and Himalayan high altitude natives at >3500 m: A cross-sectional study.

PubMed

Dhar, Priyanka; Sharma, Vijay K; Das, Saroj K; Barhwal, Kalpana; Hota, Sunil K; Singh, Shashi B

2018-04-09

We studied the differential responses of autonomic function in sea level residents (SLR), acclimatized lowlanders (ALH) in high altitude (HA) and HA natives (HAN) at >3500 m. Out of 771 male volunteers included in this cross-sectional study, SLR, ALH and HAN groups were comprised of 351, 307 and 113 volunteers, respectively. Our results showed persistent sympathetic dominance with significantly reduced (p < 0.05) parasympathetic response in ALH as compared to SLR and HAN populations. This may be attributed to significantly increased (p < 0.05) concentration of coronary risk factors and plasma catecholamines in ALH as compared to SLR and HAN. The ALH also showed significantly increased (p < 0.05) level of serum homocysteine as compared to SLR. The HAN exhibited no changes in autonomic function despite significantly elevated (p < 0.05) homocysteine level as compared to SLR. Our findings may have clinical relevance for assessment of susceptibility to cardiovascular risks in HA dwellers, native highlanders and patients with hypoxemia. Copyright © 2018 Elsevier B.V. All rights reserved.

Trial design and rationale for APOLLO, a Phase 3, placebo-controlled study of patisiran in patients with hereditary ATTR amyloidosis with polyneuropathy.

PubMed

Adams, David; Suhr, Ole B; Dyck, Peter J; Litchy, William J; Leahy, Raina G; Chen, Jihong; Gollob, Jared; Coelho, Teresa

2017-09-11

Patisiran is an investigational RNA interference (RNAi) therapeutic in development for the treatment of hereditary ATTR (hATTR) amyloidosis, a progressive disease associated with significant disability, morbidity, and mortality. Here we describe the rationale and design of the Phase 3 APOLLO study, a randomized, double-blind, placebo-controlled, global study to evaluate the efficacy and safety of patisiran in patients with hATTR amyloidosis with polyneuropathy. Eligible patients are 18-85 years old with hATTR amyloidosis, investigator-estimated survival of ≥2 years, Neuropathy Impairment Score (NIS) of 5-130, and polyneuropathy disability score ≤IIIb. Patients are randomized 2:1 to receive either intravenous patisiran 0.3 mg/kg or placebo once every 3 weeks. The primary objective is to determine the efficacy of patisiran at 18 months based on the difference in the change in modified NIS+7 (a composite measure of motor strength, sensation, reflexes, nerve conduction, and autonomic function) between the patisiran and placebo groups. Secondary objectives are to evaluate the effect of patisiran on Norfolk-Diabetic Neuropathy quality of life questionnaire score, nutritional status (as evaluated by modified body mass index), motor function (as measured by NIS-weakness and timed 10-m walk test), and autonomic symptoms (as measured by the Composite Autonomic Symptom Score-31 questionnaire). Exploratory objectives include assessment of cardiac function and pathologic evaluation to assess nerve fiber innervation and amyloid burden. Safety of patisiran will be assessed throughout the study. APOLLO represents the largest randomized, Phase 3 study to date in patients with hATTR amyloidosis, with endpoints that capture the multisystemic nature of this disease. This trial is registered at clinicaltrials.gov ( NCT01960348 ); October 9, 2013.

Context recognition and situation assessment in autonomous mobile robots

NASA Astrophysics Data System (ADS)

Yavnai, Arie

1993-05-01

The capability to recognize the operating context and to assess the situation in real-time is needed, if a high functionality autonomous mobile robot has to react properly and effectively to continuously changing situations and events, either external or internal, while the robot is performing its assigned tasks. A new approach and architecture for context recognition and situation assessment module (CORSA) is presented in this paper. CORSA is a multi-level information processing module which consists of adaptive decision and classification algorithms. It performs dynamic mapping from the data space to the context space, and dynamically decides on the context class. Learning mechanism is employed to update the decision variables so as to minimize the probability of misclassification. CORSA is embedded within the Mission Manager module of the intelligent autonomous hyper-controller (IAHC) of the mobile robot. The information regarding operating context, events and situation is then communicated to other modules of the IAHC where it is used to: (a) select the appropriate action strategy; (b) support the processes to arbitration and conflict resolution between reflexive behaviors and reasoning-driven behaviors; (c) predict future events and situations; and (d) determine criteria and priorities for planning, replanning, and decision making.

Autonomic nervous system involvement in the giant axonal neuropathy (GAN) KO mouse: implications for human disease.

PubMed

Armao, Diane; Bailey, Rachel M; Bouldin, Thomas W; Kim, Yongbaek; Gray, Steven J

2016-08-01

Giant axonal neuropathy (GAN) is an inherited severe sensorimotor neuropathy. The aim of this research was to investigate the neuropathologic features and clinical autonomic nervous system (ANS) phenotype in two GAN knockout (KO) mouse models. Little is known about ANS involvement in GAN in humans, but autonomic signs and symptoms are commonly reported in early childhood. Routine histology and immunohistochemistry was performed on GAN KO mouse specimens taken at various ages. Enteric dysfunction was assessed by quantifying the frequency, weight, and water content of defecation in GAN KO mice. Histological examination of the enteric, parasympathetic and sympathetic ANS of GAN KO mice revealed pronounced and widespread neuronal perikaryal intermediate filament inclusions. These neuronal inclusions served as an easily identifiable, early marker of GAN in young GAN KO mice. Functional studies identified an age-dependent alteration in fecal weight and defecation frequency in GAN KO mice. For the first time in the GAN KO mouse model, we described the early, pronounced and widespread neuropathologic features involving the ANS. In addition, we provided evidence for a clinical autonomic phenotype in GAN KO mice, reflected in abnormal gastrointestinal function. These findings in GAN KO mice suggest that consideration should be given to ANS involvement in human GAN, especially when considering treatments and patient care.

Spaceflight-induced cardiovascular changes and recovery during NASA's Functional Task Test

NASA Astrophysics Data System (ADS)

Arzeno, Natalia M.; Stenger, Michael B.; Bloomberg, Jacob J.; Platts, Steven H.

2013-11-01

Microgravity-induced physiologic changes could impair a crewmember's performance upon return to a gravity environment. The Functional Task Test aims to correlate these physiologic alterations with changes in performance during mission-critical tasks. In this study, we evaluated spaceflight-induced cardiovascular changes during 11 functional tasks in 7 Shuttle astronauts before spaceflight, on landing day, and 1, 6, and 30 days after landing. Mean heart rate was examined during each task and autonomic activity was approximated by heart rate variability during the Recovery from Fall/Stand Test, a 2-min prone rest followed by a 3-min stand. Heart rate was increased on landing day during all of the tasks, and remained elevated 6 days after landing during 6 of the 11 tasks. Parasympathetic modulation was diminished and sympathovagal balance was increased on landing day. Additionally, during the stand test 6 days after landing, parasympathetic modulation remained suppressed and heart rate remained elevated compared to preflight levels. Heart rate and autonomic activity were not different from preflight levels 30 days after landing. We detected changes in heart rate and autonomic activity during a 3-min stand and a variety of functional tasks, where cardiovascular deconditioning was still evident 6 days after returning from short-duration spaceflight. The delayed recovery times for heart rate and parasympathetic modulation indicate the necessity of assessing functional performance after long-duration spaceflight to ensure crew health and safety.

Autonomic Function in Infancy.

ERIC Educational Resources Information Center

Fox, Nathan A.; Fitzgerald, Hiram E.

1990-01-01

Reviews research that uses autonomic responses of human infants as dependent measures. Focuses on the history of research on the autonomic nervous system, measurement issues, and autonomic correlates of infant behavior and systems. (RJC)

Using the autonomic standards to assess orthostatic hypotension in persons with SCI: a case series.

PubMed

Wecht, Jill M; Wilson, James; Previnaire, Jean-Gabriel

2017-01-01

Spinal cord injury (SCI) creates a complex and unique syndrome of medical issues related to disruption of somatic and autonomic pathways. Among these impaired control of blood pressure (BP) can significantly impede patients' activities of daily living. The International Standards for the Assessment of Autonomic Function after SCI (ISAFSCI) is used to document the impact of SCI on resting BP (abnormal if below 90 mmHg) and the presence or absence of orthostatic hypotension (OH), defined as a symptomatic or asymptomatic decrease in BP (>/=20/10 mmHg) upon moving to an upright position. Case 1 documents the adverse influence of prescribed medications (antidepressants for neuropathic pain) on OH; case 2 describes the influence of bladder management on cardiovascular instability (autonomic dysreflexia and subsequent OH); case 3 describes the association between spasticity and OH; case 4 describes OH associated with a Valsalva maneuver. Impaired control of BP can stem from a combination of medical issues and autonomic dysfunction in persons with SCI. Management strategies for OH will vary depending on the stage of the SCI, the root cause of the OH and other confounding medical conditions. Non-pharmacological treatment should be considered as a first line of intervention and consideration should be given to cessation of potentially contributory medications prior to implementing pharmaceutical interventions. The systematic use of ISAFSCI by clinicians is recommended to document BP irregularities and to describe the effects of treatment strategies aimed at improving BP control in the SCI population.

Autonomous Integrated Receive System (AIRS) requirements definition. Volume 2: Design and development

NASA Technical Reports Server (NTRS)

Chie, C. M.; White, M. A.; Lindsey, W. C.; Davarian, F.; Dixon, R. C.

1984-01-01

Functional requirements and specifications are defined for an autonomous integrated receive system (AIRS) to be used as an improvement in the current tracking and data relay satellite system (TDRSS), and as a receiving system in the future tracking and data acquisition system (TDAS). The AIRS provides improved acquisition, tracking, bit error rate (BER), RFI mitigation techniques, and data operations performance compared to the current TDRSS ground segment receive system. A computer model of the AIRS is used to provide simulation results predicting the performance of AIRS. Cost and technology assessments are included.

Exploring the Relationship of Autonomic and Endocrine Activity with Social Functioning in Adults with Autism Spectrum Disorders

ERIC Educational Resources Information Center

Smeekens, I.; Didden, R.; Verhoeven, E. W. M.

2015-01-01

Several studies indicate that autonomic and endocrine activity may be related to social functioning in individuals with autism spectrum disorder (ASD), although the number of studies in adults is limited. The present study explored the relationship of autonomic and endocrine activity with social functioning in young adult males with ASD compared…

Understanding the physiology of mindfulness: aortic hemodynamics and heart rate variability.

PubMed

May, Ross W; Bamber, Mandy; Seibert, Gregory S; Sanchez-Gonzalez, Marcos A; Leonard, Joseph T; Salsbury, Rebecca A; Fincham, Frank D

2016-01-01

Data were collected to examine autonomic and hemodynamic cardiovascular modulation underlying mindfulness from two independent samples. An initial sample (N = 185) underwent laboratory assessments of central aortic blood pressure and myocardial functioning to investigated the association between mindfulness and cardiac functioning. Controlling for religiosity, mindfulness demonstrated a strong negative relationship with myocardial oxygen consumption and left ventricular work but not heart rate or blood pressure. A second sample (N = 124) underwent a brief (15 min) mindfulness inducing intervention to examine the influence of mindfulness on cardiovascular autonomic modulation via blood pressure variability and heart rate variability. The intervention had a strong positive effect on cardiovascular modulation by decreasing cardiac sympathovagal tone, vasomotor tone, vascular resistance and ventricular workload. This research establishes a link between mindfulness and cardiovascular functioning via correlational and experimental methodologies in samples of mostly female undergraduates. Future directions for research are outlined.

Autonomic Recovery Is Delayed in Chinese Compared with Caucasian following Treadmill Exercise.

PubMed

Sun, Peng; Yan, Huimin; Ranadive, Sushant M; Lane, Abbi D; Kappus, Rebecca M; Bunsawat, Kanokwan; Baynard, Tracy; Hu, Min; Li, Shichang; Fernhall, Bo

2016-01-01

Caucasian populations have a higher prevalence of cardiovascular disease (CVD) when compared with their Chinese counterparts and CVD is associated with autonomic function. It is unknown whether autonomic function during exercise recovery differs between Caucasians and Chinese. The present study investigated autonomic recovery following an acute bout of treadmill exercise in healthy Caucasians and Chinese. Sixty-two participants (30 Caucasian and 32 Chinese, 50% male) performed an acute bout of treadmill exercise at 70% of heart rate reserve. Heart rate variability (HRV) and baroreflex sensitivity (BRS) were obtained during 5-min epochs at pre-exercise, 30-min, and 60-min post-exercise. HRV was assessed using frequency [natural logarithm of high (LnHF) and low frequency (LnLF) powers, normalized high (nHF) and low frequency (nLF) powers, and LF/HF ratio] and time domains [Root mean square of successive differences (RMSSD), natural logarithm of RMSSD (LnRMSSD) and R-R interval (RRI)]. Spontaneous BRS included both up-up and down-down sequences. At pre-exercise, no group differences were observed for any HR, HRV and BRS parameters. During exercise recovery, significant race-by-time interactions were observed for LnHF, nHF, nLF, LF/HF, LnRMSSD, RRI, HR, and BRS (up-up). The declines in LnHF, nHF, RMSSD, RRI and BRS (up-up) and the increases in LF/HF, nLF and HR were blunted in Chinese when compared to Caucasians from pre-exercise to 30-min to 60-min post-exercise. Chinese exhibited delayed autonomic recovery following an acute bout of treadmill exercise. This delayed autonomic recovery may result from greater sympathetic dominance and extended vagal withdrawal in Chinese. Chinese Clinical Trial Register ChiCTR-IPR-15006684.

Autonomic Recovery Is Delayed in Chinese Compared with Caucasian following Treadmill Exercise

PubMed Central

Sun, Peng; Yan, Huimin; Ranadive, Sushant M.; Lane, Abbi D.; Kappus, Rebecca M.; Bunsawat, Kanokwan; Baynard, Tracy; Hu, Min; Li, Shichang; Fernhall, Bo

2016-01-01

Caucasian populations have a higher prevalence of cardiovascular disease (CVD) when compared with their Chinese counterparts and CVD is associated with autonomic function. It is unknown whether autonomic function during exercise recovery differs between Caucasians and Chinese. The present study investigated autonomic recovery following an acute bout of treadmill exercise in healthy Caucasians and Chinese. Sixty-two participants (30 Caucasian and 32 Chinese, 50% male) performed an acute bout of treadmill exercise at 70% of heart rate reserve. Heart rate variability (HRV) and baroreflex sensitivity (BRS) were obtained during 5-min epochs at pre-exercise, 30-min, and 60-min post-exercise. HRV was assessed using frequency [natural logarithm of high (LnHF) and low frequency (LnLF) powers, normalized high (nHF) and low frequency (nLF) powers, and LF/HF ratio] and time domains [Root mean square of successive differences (RMSSD), natural logarithm of RMSSD (LnRMSSD) and R–R interval (RRI)]. Spontaneous BRS included both up-up and down-down sequences. At pre-exercise, no group differences were observed for any HR, HRV and BRS parameters. During exercise recovery, significant race-by-time interactions were observed for LnHF, nHF, nLF, LF/HF, LnRMSSD, RRI, HR, and BRS (up-up). The declines in LnHF, nHF, RMSSD, RRI and BRS (up-up) and the increases in LF/HF, nLF and HR were blunted in Chinese when compared to Caucasians from pre-exercise to 30-min to 60-min post-exercise. Chinese exhibited delayed autonomic recovery following an acute bout of treadmill exercise. This delayed autonomic recovery may result from greater sympathetic dominance and extended vagal withdrawal in Chinese. Trial Registration: Chinese Clinical Trial Register ChiCTR-IPR-15006684 PMID:26784109

Heart rate variability measure in breast cancer patients and survivors: A systematic review.

PubMed

Arab, Claudia; Dias, Daniel Penteado Martins; Barbosa, Renata Thaís de Almeida; Carvalho, Tatiana Dias de; Valenti, Vitor Engrácia; Crocetta, Tânia Brusque; Ferreira, Marcelo; Abreu, Luiz Carlos de; Ferreira, Celso

2016-06-01

In the current study, we aimed to review literature findings showing the clinical importance of cardiac autonomic modulation assessed by heart rate variability analysis in breast cancer (BC) patients and survivors. We conducted a systematic review according to The PRISMA Statement in Medline, Scopus and Web of Science (_-2015) databases. The search was limited to articles in English language, published in peer-reviewed journals, and with adult age samples only (e.g., women, patients, or survivors, diagnosed with BC in any stage). We included observational studies and randomized trials. Detailed heart rate variability analysis (instruments, data collection protocol, and analysis methods) was required. Search terms included autonomic nervous system, heart rate variability, sympathetic and parasympathetic nervous system, autonomic dysfunction, vagal nervous and breast neoplasms, breast cancer and breast tumor. Twelve studies were included in this review. The clinical importance of cardiac autonomic modulation assessed by heart rate variability analysis in BC patients and survivors is demonstrated by association with effects of BC surgery, and treatments, and the adverse effects of surgery and treatments on survivors (e.g., cardiotoxicity, fatigue, and stress). The strength of evidence of included studies is low: small samples size and heterogeneity, presence of confounders, and observational studies design. The heart rate variability analysis could be used as a complementary non-invasive tool for the early diagnosis and better prognosis of autonomic dysfunction, and survival in BC patients. There are many potential clinical applications of heart rate variability analysis in BC patients, and the employment of such approaches could lead to lower impairment of autonomic function in this individuals. Copyright © 2016 Elsevier Ltd. All rights reserved.

Autonomic arousal and learning in Web-based simulation: a feasibility study.

PubMed

Gorrindo, Tristan; Chevalier, Lydia; Goldfarb, Elizabeth; Hoeppner, Bettina B; Birnbaum, Robert J

2014-01-01

Autonomic arousal is an important component of understanding learning as it is related to cognitive effort, attention, and emotional arousal. Currently, however, little is known about its relationship to online education. We conducted a study to determine the feasibility of measuring autonomic arousal and engagement in online continuing medical education (CME). Using the Computer Simulation Assessment Tool (CSAT) platform, health care providers were randomly assigned to either high- or low-valence versions of a Web-based simulation on risk assessment for a returning veteran. Data were collected on participants' actions within the simulation, self-reported cognitive engagement, knowledge retention, and autonomic arousal measured using galvanic skin response (GSR). Participants in the high-valence condition (n = 7) chose a lower percentage of critical actions (M = 79.2, SD = 4.2) than participants in the low valence (n = 8) condition (M = 83.9, SD = 3.6, t(1,14) = 2.44, p = .03). While not statistically significant, high-valence participants reported higher cognitive engagement. Participants in the high-valence condition showed a larger increase in physiologic arousal when comparing mean tonic GSR during the orientation simulation to the study simulation (high-valence mean difference = 4.21 μS, SD = 1.23 vs low-valence mean difference = 1.64 μS, SD = 2.32, t(1,13) = -2.62, p = .01). In addition to being consistent with previous engagement research, this experiment functioned as a feasibility study for measuring autonomic arousal in online CME. The current study provides a framework for future studies, which may use neurophysiology to identify the critical autonomic and engagement components associated with effective online learning. © 2014 The Alliance for Continuing Education in the Health Professions, the Society for Academic Continuing Medical Education, and the Council on Continuing Medical Education, Association for Hospital Medical Education.

Autonomic function in manganese alloy workers

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

Barrington, W.W.; Angle, C.R.; Willcockson, N.K.

1998-07-01

The observation of orthostatic hypotension in an index case of manganese toxicity lead to this prospective attempt to evaluate cardiovascular autonomic function and cognitive and emotional neurotoxicity in eight manganese alloy welders and machinists. The subjects consisted of a convenience sample consisting of an index case of manganese dementia, his four co-workers in a frog shop for gouging, welding, and grinding repair of high manganese railway track and a convenience sample of three mild steel welders with lesser manganese exposure also referred because of cognitive or autonomic symptoms. Frog shop air manganese samples 9.6--10 years before and 1.2--3.4 years aftermore » the diagnosis of the index case exceeded 1.0 mg/m{sup 3} in 29% and 0.2 mg/m{sup 3} in 62%. Twenty-four-hour electrocardiographic (Holter) monitoring was used to determine the temporal variability of the heartrate (RR{prime} interval) and the rates of change at low frequency and high frequency. MMPI and MCMI personality assessment and short-term memory, figure copy, controlled oral word association, and symbol digit tests were used.« less

Impact of aging on cardiac function in a female rat model of menopause: role of autonomic control, inflammation, and oxidative stress.

PubMed

Machi, Jacqueline Freire; Dias, Danielle da Silva; Freitas, Sarah Cristina; de Moraes, Oscar Albuquerque; da Silva, Maikon Barbosa; Cruz, Paula Lázara; Mostarda, Cristiano; Salemi, Vera M C; Morris, Mariana; De Angelis, Kátia; Irigoyen, Maria-Cláudia

2016-01-01

The aim of this study was to evaluate the effects of aging on metabolic, cardiovascular, autonomic, inflammatory, and oxidative stress parameters after ovarian hormone deprivation (OVX). Female Wistar rats (3 or 22 months old) were divided into: young controls, young ovariectomized, old controls, and old ovariectomized (bilateral ovaries removal). After a 9-week follow-up, physical capacity, metabolic parameters, and morphometric and cardiac functions were assessed. Subsequently, arterial pressure was recorded and cardiac autonomic control was evaluated. Oxidative stress was measured on the cardiac tissue, while inflammatory profile was assessed in the plasma. Aging or OVX caused an increase in body and fat weight and triglyceride concentration and a decrease in both insulin sensitivity and aerobic exercise capacity. Left ventricular diastolic dysfunction and increased cardiac overload (myocardial performance index) were reported in old groups when compared with young groups. Aging and OVX led to an increased sympathetic tonus, and vagal tonus was lower only for the old groups. Tumor necrosis factor-α and interleukin-6 were increased in old groups when compared with young groups. Glutathione redox balance (GSH/GSSG) was reduced in young ovariectomized, old controls, and old ovariectomized groups when compared with young controls, indicating an increased oxidative stress. A negative correlation was found between GSH/GSSG and tumor necrosis factor-α (r=-0.6, P<0.003). Correlations were found between interleukin-6 with adipose tissue (r=0.5, P<0.009) and vagal tonus (r=-0.7, P<0.0002); and among myocardial performance index with interleukin-6 (r=0.65, P<0.0002), sympathetic tonus (r=0.55, P<0.006), and physical capacity (r=-0.55, P<0.003). The findings in this trial showed that ovariectomy aggravated the impairment of cardiac and functional effects of aging in female rats, probably associated with exacerbated autonomic dysfunction, inflammation, and oxidative stress.

Autonomic status and pain profile in patients of chronic low back pain and following electro acupuncture therapy: a randomized control trial.

PubMed

Shankar, Nilima; Thakur, Manisha; Tandon, Om Prakash; Saxena, Ashok Kumar; Arora, Shobha; Bhattacharya, Neena

2011-01-01

Pain is a syndrome characterized by several neurophysiological changes including that of the autonomic nervous system. Chronic low back pain (LBP) is a major health problem and is a frequent reason for using unconventional therapies especially acupuncture. This study was conducted to evaluate the autonomic status and pain profile in chronic LBP patients and to observe the effect of electro acupuncture therapy. Chronic LBP patients (n=60) were recruited from the Department of Orthopaedics, GTB Hospital, Delhi. Age and sex matched healthy volunteers were selected as controls (n=30). Following a written consent, LBP patients were randomly allocated into two study groups - Group A received 10 sittings of electro acupuncture, on alternate days, at GB and UB points selected for back pain, while the Group B received a conventional drug therapy in the form of oral Valdecoxib together with supervised physiotherapy. Controls were assessed once while the patients were assessed twice, before and after completion of the treatment program (3 weeks). The autonomic status was studied with non-invasive cardiovascular autonomic function tests which included E: I ratio, 30:15 ratio, postural challenge test and sustained handgrip test. Pain intensity was measured with the visual analogue scale (VAS) and the global perceived effect (GPE). Statistical analysis was performed using repeated measure's ANOVA with Tukey's test. Pain patients showed a significantly reduced vagal tone and increased sympathetic activity as compared to the controls (P<0.05 to P<0.001 in different variables). Following treatment, both the study groups showed a reduction in vagal tone together with a decrease in the sympathetic activity. There was also a considerable relief of pain in both groups, however, the acupuncture group showed a better response (P<0.01). We conclude that there is autonomic dysfunction in chronic LBP patients. Acupuncture effectively relieves the pain and improves the autonomic status and hence can be used as an alternative/additive treatment modality in these cases.

Clinical classification and neuro-vestibular evaluation in chronic dizziness.

PubMed

Oh, Sun-Young; Kim, Do-Hyung; Yang, Tae-Ho; Shin, Byoung-Soo; Jeong, Seul-Ki

2015-01-01

This study attempts to clarify the clinical characteristics of chronic dizziness and its relationships with specific vestibular, oculomotor, autonomic and psychiatric dysfunctions. 73 Patients with idiopathic chronic dizziness were recruited and classified based on history taking and clinical examination into the following four clinical subgroups; vestibular migraine (VM), dysautonomia, psychogenic, and unspecified groups. They were also evaluated using oculomotor, otolithic and autonomic function tests, and psychologic investigation. Patients in the VM group showed a high proportion of abnormality on smooth pursuit and otolithic function testing compared to the other groups. The dysautonomia group revealed significant abnormalities in sympathetic and cardiovagal autonomic function, while the psychogenic group had a high frequency of abnormality in sympathetic autonomic testing and in Beck's anxiety inventory scale. The unspecified group showed abnormalities on saccade, smooth pursuit and autonomic function testing. Clinical classification of patients with chronic dizziness was relevant and they showed a correlation with disease-specific abnormal results in oculomotor, otolithic, autonomic function and psychology testing. Appropriate diagnostic investigation based on precise clinical diagnosis of chronic dizziness reduces the need for extensive laboratory testing, neuroimaging, and other low-yield tests. Copyright © 2014 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.

Carotid Body Ablation Abrogates Hypertension and Autonomic Alterations Induced by Intermittent Hypoxia in Rats.

PubMed

Del Rio, Rodrigo; Andrade, David C; Lucero, Claudia; Arias, Paulina; Iturriaga, Rodrigo

2016-08-01

Chronic intermittent hypoxia (CIH), the main feature of obstructive sleep apnea, enhances carotid body (CB) chemosensory responses to hypoxia and produces autonomic dysfunction, cardiac arrhythmias, and hypertension. We tested whether autonomic alterations, arrhythmogenesis, and the progression of hypertension induced by CIH depend on the enhanced CB chemosensory drive, by ablation of the CB chemoreceptors. Male Sprague-Dawley rats were exposed to control (Sham) conditions for 7 days and then to CIH (5% O2, 12/h 8 h/d) for a total of 28 days. At 21 days of CIH exposure, rats underwent bilateral CB ablation and then exposed to CIH for 7 additional days. Arterial blood pressure and ventilatory chemoreflex response to hypoxia were measured in conscious rats. In addition, cardiac autonomic imbalance, cardiac baroreflex gain, and arrhythmia score were assessed during the length of the experiments. In separate experimental series, we measured extracellular matrix remodeling content in cardiac atrial tissue and systemic oxidative stress. CIH induced hypertension, enhanced ventilatory response to hypoxia, induced autonomic imbalance toward sympathetic preponderance, reduced baroreflex gain, and increased arrhythmias and atrial fibrosis. CB ablation normalized blood pressure, reduced ventilatory response to hypoxia, and restored cardiac autonomic and baroreflex function. In addition, CB ablation reduced the number of arrhythmias, but not extracellular matrix remodeling or systemic oxidative stress, suggesting that reductions in arrhythmia incidence during CIH were related to normalization of cardiac autonomic balance. Present results show that autonomic alterations induced by CIH are critically dependent on the CB and support a main role for the CB in the CIH-induced hypertension. © 2016 American Heart Association, Inc.

Potential benefits of mindfulness during pregnancy on maternal autonomic nervous system function and infant development.

PubMed

Braeken, Marijke A K A; Jones, Alexander; Otte, Renée A; Nyklíček, Ivan; Van den Bergh, Bea R H

2017-02-01

Mindfulness is known to decrease psychological distress. Possible benefits in pregnancy have rarely been explored. Our aim was to examine the prospective association of mindfulness with autonomic nervous system function during pregnancy and with later infant social-emotional development. Pregnant women (N = 156) completed self-report mindfulness and emotional distress questionnaires, and had their autonomic function assessed in their first and third trimesters, including heart rate (HR), indices of heart rate variability (HRV), preejection period (PEP), and systolic (SBP) and diastolic blood pressure (DBP). The social-emotional development of 109 infants was assessed at 4 months of age. More mindful pregnant women had less prenatal and postnatal emotional distress (p < .001) and higher cardiac parasympathetic activity: root mean square of successive differences (RMSSD: p = .03) and high-frequency (HF) HRV (p = .02). Between the first and third trimesters, women's overall HR increased (p < .001), and HRV (RMSSD, HF HRV, and low-frequency (LF) HRV: p < .001) and PEP decreased (p < .001). In more mindful mothers, parasympathetic activity decreased less (RMSSD: p = .01; HF HRV: p = .03) and sympathetic activity (inversely related to PEP) increased less (PEP: p = .02) between trimesters. Their offspring displayed less negative social-emotional behavior (p = .03) compared to offspring of less mindful mothers. Mindfulness in pregnancy was associated with ANS changes likely to be adaptive and with better social-emotional offspring development. Interventions to increase mindfulness during pregnancy might improve maternal and offspring health, but randomized trials are needed to demonstrate this. © 2016 Society for Psychophysiological Research.

Heart rate variability biofeedback in patients with alcohol dependence: a randomized controlled study

PubMed Central

Penzlin, Ana Isabel; Siepmann, Timo; Illigens, Ben Min-Woo; Weidner, Kerstin; Siepmann, Martin

2015-01-01

Background and objective In patients with alcohol dependence, ethyl-toxic damage of vasomotor and cardiac autonomic nerve fibers leads to autonomic imbalance with neurovascular and cardiac dysfunction, the latter resulting in reduced heart rate variability (HRV). Autonomic imbalance is linked to increased craving and cardiovascular mortality. In this study, we sought to assess the effects of HRV biofeedback training on HRV, vasomotor function, craving, and anxiety. Methods We conducted a randomized controlled study in 48 patients (14 females, ages 25–59 years) undergoing inpatient rehabilitation treatment. In the treatment group, patients (n=24) attended six sessions of HRV biofeedback over 2 weeks in addition to standard rehabilitative care, whereas, in the control group, subjects received standard care only. Psychometric testing for craving (Obsessive Compulsive Drinking Scale), anxiety (Symptom Checklist-90-Revised), HRV assessment using coefficient of variation of R-R intervals (CVNN) analysis, and vasomotor function assessment using laser Doppler flowmetry were performed at baseline, immediately after completion of treatment or control period, and 3 and 6 weeks afterward (follow-ups 1 and 2). Results Psychometric testing showed decreased craving in the biofeedback group immediately postintervention (OCDS scores: 8.6±7.9 post-biofeedback versus 13.7±11.0 baseline [mean ± standard deviation], P<0.05), whereas craving was unchanged at this time point in the control group. Anxiety was reduced at follow-ups 1 and 2 post-biofeedback, but was unchanged in the control group (P<0.05). Following biofeedback, CVNN tended to be increased (10.3%±2.8% post-biofeedback, 10.1%±3.5% follow-up 1, 10.1%±2.9% follow-up 2 versus 9.7%±3.6% baseline; P=not significant). There was no such trend in the control group. Vasomotor function assessed using the mean duration to 50% vasoconstriction of cutaneous vessels after deep inspiration was improved following biofeedback immediately postintervention and was unchanged in the control group (P<0.05). Conclusion Our data indicate that HRV biofeedback might be useful to decrease anxiety, increase HRV, and improve vasomotor function in patients with alcohol dependence when complementing standard rehabilitative inpatient care. PMID:26557753

Sensitization of the Nociceptive System in Complex Regional Pain Syndrome

PubMed Central

Diedrichs, Carolina; Baron, Ralf; Gierthmühlen, Janne

2016-01-01

Background Complex regional pain syndrome type I (CRPS-I) is characterized by sensory, motor and autonomic abnormalities without electrophysiological evidence of a nerve lesion. Objective Aims were to investigate how sensory, autonomic and motor function change in the course of the disease. Methods 19 CRPS-I patients (17 with acute, 2 with chronic CRPS, mean duration of disease 5.7±8.3, range 1–33 months) were examined with questionnaires (LANSS, NPS, MPI, Quick DASH, multiple choice list of descriptors for sensory, motor, autonomic symptoms), motor and autonomic tests as well as quantitative sensory testing according to the German Research Network on Neuropathic Pain at two visits (baseline and 36±10.6, range 16–53 months later). Results CRPS-I patients had an improvement of sudomotor and vasomotor function, but still a great impairment of sensory and motor function upon follow-up. Although pain and mechanical detection improved upon follow-up, thermal and mechanical pain sensitivity increased, including the contralateral side. Increase in mechanical pain sensitivity and loss of mechanical detection were associated with presence of ongoing pain. Conclusions The results demonstrate that patients with CRPS-I show a sensitization of the nociceptive system in the course of the disease, for which ongoing pain seems to be the most important trigger. They further suggest that measured loss of function in CRPS-I is due to pain-induced hypoesthesia rather than a minimal nerve lesion. In conclusion, this article gives evidence for a pronociceptive pain modulation profile developing in the course of CRPS and thus helps to assess underlying mechanisms of CRPS that contribute to the maintenance of patients’ pain and disability. PMID:27149519

Revisiting the physiological effects of exercise training on autonomic regulation and chemoreflex control in heart failure: does ejection fraction matter?

PubMed

Andrade, David C; Arce-Alvarez, Alexis; Toledo, Camilo; Díaz, Hugo S; Lucero, Claudia; Quintanilla, Rodrigo A; Schultz, Harold D; Marcus, Noah J; Amann, Markus; Del Rio, Rodrigo

2018-03-01

Heart failure (HF) is a global public health problem that, independent of its etiology [reduced (HFrEF) or preserved ejection fraction (HFpEF)], is characterized by functional impairments of cardiac function, chemoreflex hypersensitivity, baroreflex sensitivity (BRS) impairment, and abnormal autonomic regulation, all of which contribute to increased morbidity and mortality. Exercise training (ExT) has been identified as a nonpharmacological therapy capable of restoring normal autonomic function and improving survival in patients with HFrEF. Improvements in autonomic function after ExT are correlated with restoration of normal peripheral chemoreflex sensitivity and BRS in HFrEF. To date, few studies have addressed the effects of ExT on chemoreflex control, BRS, and cardiac autonomic control in HFpEF; however, there are some studies that have suggested that ExT has a beneficial effect on cardiac autonomic control. The beneficial effects of ExT on cardiac function and autonomic control in HF may have important implications for functional capacity in addition to their obvious importance to survival. Recent studies have suggested that the peripheral chemoreflex may also play an important role in attenuating exercise intolerance in HFrEF patients. The role of the central/peripheral chemoreflex, if any, in mediating exercise intolerance in HFpEF has not been investigated. The present review focuses on recent studies that address primary pathophysiological mechanisms of HF (HFrEF and HFpEF) and the potential avenues by which ExT exerts its beneficial effects.

Assessment of cardiac autonomic functions by heart rate recovery, heart rate variability and QT dynamicity parameters in patients with acromegaly.

PubMed

Dural, Muhammet; Kabakcı, Giray; Cınar, Neşe; Erbaş, Tomris; Canpolat, Uğur; Gürses, Kadri Murat; Tokgözoğlu, Lale; Oto, Ali; Kaya, Ergün Barış; Yorgun, Hikmet; Sahiner, Levent; Dağdelen, Selçuk; Aytemir, Kudret

2014-04-01

Cardiovascular complications are the most common causes of morbidity and mortality in acromegaly. However, there is little data regarding cardiac autonomic functions in these patients. Herein, we aimed to investigate several parameters of cardiac autonomic functions in patients with acromegaly compared to healthy subjects. We enrolled 20 newly diagnosed acromegalic patients (55% female, age:45.7 ± 12.6 years) and 32 age- and gender-matched healthy subjects. All participants underwent 24 h Holter recording. Heart rate recovery (HRR) indices were calculated by subtracting 1st, 2nd and 3rd minute heart rates from maximal heart rate. All patients underwent heart rate variability (HRV) and QT dynamicity analysis. Baseline characteristics were similar except diabetes mellitus and hypertension among groups. Mean HRR1 (29.2 ± 12.3 vs 42.6 ± 6.5, p = 0.001), HRR2 (43.5 ± 15.6 vs 61.1 ± 10.8, p = 0.001) and HRR3 (46.4 ± 16.2 vs 65.8 ± 9.8, p = 0.001) values were significantly higher in control group. HRV parameters as, SDNN [standard deviation of all NN intervals] (p = 0.001), SDANN [SD of the 5 min mean RR intervals] (p = 0.001), RMSSD [root square of successive differences in RR interval] (p = 0.001), PNN50 [proportion of differences in successive NN intervals >50 ms] (p = 0.001) and high-frequency [HF] (p = 0.001) were significantly decreased in patients with acromegaly; but low frequency [LF] (p = 0.046) and LF/HF (p = 0.001) were significantly higher in acromegaly patients. QTec (p = 0.009), QTac/RR slope (p = 0.017) and QTec/RR slope (p = 0.01) were significantly higher in patients with acromegaly. Additionally, there were significant negative correlation of disease duration with HRR2, HRR3, SDNN, PNN50, RMSSD, variability index. Our study results suggest that cardiac autonomic functions are impaired in patients with acromegaly. Further large scale studies are needed to exhibit the prognostic significance of impaired autonomic functions in patients with acromegaly.

Autonomic deficit not the cause of death in West Nile virus neurological disease.

PubMed

Wang, Hong; Siddharthan, Venkatraman; Hall, Jeffery O; Morrey, John D

2014-02-01

Some West Nile virus (WNV)-infected patients have been reported to manifest disease signs consistent with autonomic dysfunction. Moreover, WNV infection in hamsters causes reduced electromyography amplitudes of the gastrointestinal tract and diaphragm, and they have reduced heart rate variability (HRV), a read-out for the parasympathetic autonomic function. HRV was measured in both hamsters and mice using radiotelemetry to identify autonomic deficits. To identify areas of WNV infection within the medulla oblongata mapping to the dorsal motor nucleus of vagus (DMNV) and the nucleus ambiguus (NA), fluorogold dye was injected into the cervical trunk of the vagus nerve of hamsters. As a measurement of the loss of parasympathetic function, tachycardia was monitored contiguously over the time course of the disease. Decrease of HRV did not occur in all animals that died, which is not consistent with autonomic function being the mechanism of death. Fluorogold-stained cells in the DMNV were not stained for WNV envelope protein. Fourteen percent of WNV-stained cells were co-localized with fluorogold-stained cells in the NA. These data, however, did not suggest a fatal loss of autonomic functions because tachycardia was not observed in WNV-infected hamsters. Parasympathetic autonomic function deficit was not a likely mechanism of death in WNV-infected rodents and possibly in human patients with fatal WN neurological disease.

Alleviating Autonomic Dysreflexia after Spinal Cord Injury

DTIC Science & Technology

2017-12-01

autonomic disorders greatly influence the functional, psychological , and socioeconomic aspects of patients’ lives. Compared to numer- ous...The disruption of descending autonomic pathways renders abnormalities in multiple organ systems including cardiovascular function, respiration...the rise in blood pressure, the integration center in the brainstem transmits signals to the heart via parasympathetic pathways to reduce the heart

Mathematical assessment of the role of temperature and rainfall on mosquito population dynamics.

PubMed

Abdelrazec, Ahmed; Gumel, Abba B

2017-05-01

A new stage-structured model for the population dynamics of the mosquito (a major vector for numerous vector-borne diseases), which takes the form of a deterministic system of non-autonomous nonlinear differential equations, is designed and used to study the effect of variability in temperature and rainfall on mosquito abundance in a community. Two functional forms of eggs oviposition rate, namely the Verhulst-Pearl logistic and Maynard-Smith-Slatkin functions, are used. Rigorous analysis of the autonomous version of the model shows that, for any of the oviposition functions considered, the trivial equilibrium of the model is locally- and globally-asymptotically stable if a certain vectorial threshold quantity is less than unity. Conditions for the existence and global asymptotic stability of the non-trivial equilibrium solutions of the model are also derived. The model is shown to undergo a Hopf bifurcation under certain conditions (and that increased density-dependent competition in larval mortality reduces the likelihood of such bifurcation). The analyses reveal that the Maynard-Smith-Slatkin oviposition function sustains more oscillations than the Verhulst-Pearl logistic function (hence, it is more suited, from ecological viewpoint, for modeling the egg oviposition process). The non-autonomous model is shown to have a globally-asymptotically stable trivial periodic solution, for each of the oviposition functions, when the associated reproduction threshold is less than unity. Furthermore, this model, in the absence of density-dependent mortality rate for larvae, has a unique and globally-asymptotically stable periodic solution under certain conditions. Numerical simulations of the non-autonomous model, using mosquito surveillance and weather data from the Peel region of Ontario, Canada, show a peak mosquito abundance for temperature and rainfall values in the range [Formula: see text]C and [15-35] mm, respectively. These ranges are recorded in the Peel region between July and August (hence, this study suggests that anti-mosquito control effects should be intensified during this period).

Temperament affects sympathetic nervous function in a normal population.

PubMed

Kim, Bora; Lee, Jae-Hon; Kang, Eun-Ho; Yu, Bum-Hee

2012-09-01

Although specific temperaments have been known to be related to autonomic nervous function in some psychiatric disorders, there are few studies that have examined the relationship between temperaments and autonomic nervous function in a normal population. In this study, we examined the effect of temperament on the sympathetic nervous function in a normal population. Sixty eight healthy subjects participated in the present study. Temperament was assessed using the Korean version of the Cloninger Temperament and Character Inventory (TCI). Autonomic nervous function was determined by measuring skin temperature in a resting state, which was recorded for 5 minutes from the palmar surface of the left 5th digit using a thermistor secured with a Velcro® band. Pearson's correlation analysis and multiple linear regression were used to examine the relationship between temperament and skin temperature. A higher harm avoidance score was correlated with a lower skin temperature (i.e. an increased sympathetic tone; r=-0.343, p=0.004) whereas a higher persistence score was correlated with a higher skin temperature (r=0.433, p=0.001). Hierarchical linear regression analysis revealed that harm avoidance was able to predict the variance of skin temperature independently, with a variance of 7.1% after controlling for sex, blood pressure and state anxiety and persistence was the factor predicting the variance of skin temperature with a variance of 5.0%. These results suggest that high harm avoidance is related to an increased sympathetic nervous function whereas high persistence is related to decreased sympathetic nervous function in a normal population.

Temperament Affects Sympathetic Nervous Function in a Normal Population

PubMed Central

Kim, Bora; Lee, Jae-Hon; Kang, Eun-Ho

2012-01-01

Objective Although specific temperaments have been known to be related to autonomic nervous function in some psychiatric disorders, there are few studies that have examined the relationship between temperaments and autonomic nervous function in a normal population. In this study, we examined the effect of temperament on the sympathetic nervous function in a normal population. Methods Sixty eight healthy subjects participated in the present study. Temperament was assessed using the Korean version of the Cloninger Temperament and Character Inventory (TCI). Autonomic nervous function was determined by measuring skin temperature in a resting state, which was recorded for 5 minutes from the palmar surface of the left 5th digit using a thermistor secured with a Velcro® band. Pearson's correlation analysis and multiple linear regression were used to examine the relationship between temperament and skin temperature. Results A higher harm avoidance score was correlated with a lower skin temperature (i.e. an increased sympathetic tone; r=-0.343, p=0.004) whereas a higher persistence score was correlated with a higher skin temperature (r=0.433, p=0.001). Hierarchical linear regression analysis revealed that harm avoidance was able to predict the variance of skin temperature independently, with a variance of 7.1% after controlling for sex, blood pressure and state anxiety and persistence was the factor predicting the variance of skin temperature with a variance of 5.0%. Conclusion These results suggest that high harm avoidance is related to an increased sympathetic nervous function whereas high persistence is related to decreased sympathetic nervous function in a normal population. PMID:22993530

Central fat influences cardiac autonomic function in obese and overweight girls.

PubMed

Soares-Miranda, Luisa; Alves, Alberto J; Vale, Susana; Aires, Luisa; Santos, Rute; Oliveira, José; Mota, Jorge

2011-10-01

It has been suggested that upper-body fat compared with lower-body fat is more closely associated with cardiovascular abnormalities. Our objective was to analyze the relationship between central fat (CF) and cardiac autonomic (cANS) function in obese and overweight girls. Children were classified in two groups based on CF: those above (CFa(50)) and those below the 50th percentile (CFb(50)) of the entire sample. This study included 16 female children who were diagnosed as being overweight or obese (age: 14.3 ± 2.8 years; weight: 75.0 ± 15.8 kg; height: 157.1 ± 8.9 cm; body mass index: 30.1 ± 5.4; and total body fat: 40.5 ± 5.0%; Tanner stage: 4). cANS function was assessed through heart rate variability (HRV) and CF parameters by dual-energy X-ray absorptiometry. Female children with higher CF exhibited significantly higher sympathetic and lower parasympathetic modulation than those with lower CF, independently of total body fat. The data of the present study indicate that CF is associated with less favorable indexes of HRV. In addition, our findings suggest that CF might be an important measure to assess the effect of obesity on cANS function in female children.

Knowledge-based and integrated monitoring and diagnosis in autonomous power systems

NASA Technical Reports Server (NTRS)

Momoh, J. A.; Zhang, Z. Z.

1990-01-01

A new technique of knowledge-based and integrated monitoring and diagnosis (KBIMD) to deal with abnormalities and incipient or potential failures in autonomous power systems is presented. The KBIMD conception is discussed as a new function of autonomous power system automation. Available diagnostic modelling, system structure, principles and strategies are suggested. In order to verify the feasibility of the KBIMD, a preliminary prototype expert system is designed to simulate the KBIMD function in a main electric network of the autonomous power system.

Abnormal cardiac autonomic regulation in mice lacking ASIC3.

PubMed

Cheng, Ching-Feng; Kuo, Terry B J; Chen, Wei-Nan; Lin, Chao-Chieh; Chen, Chih-Cheng

2014-01-01

Integration of sympathetic and parasympathetic outflow is essential in maintaining normal cardiac autonomic function. Recent studies demonstrate that acid-sensing ion channel 3 (ASIC3) is a sensitive acid sensor for cardiac ischemia and prolonged mild acidification can open ASIC3 and evoke a sustained inward current that fires action potentials in cardiac sensory neurons. However, the physiological role of ASIC3 in cardiac autonomic regulation is not known. In this study, we elucidate the role of ASIC3 in cardiac autonomic function using Asic3(-/-) mice. Asic3(-/-) mice showed normal baseline heart rate and lower blood pressure as compared with their wild-type littermates. Heart rate variability analyses revealed imbalanced autonomic regulation, with decreased sympathetic function. Furthermore, Asic3(-/-) mice demonstrated a blunted response to isoproterenol-induced cardiac tachycardia and prolonged duration to recover to baseline heart rate. Moreover, quantitative RT-PCR analysis of gene expression in sensory ganglia and heart revealed that no gene compensation for muscarinic acetylcholines receptors and beta-adrenalin receptors were found in Asic3(-/-) mice. In summary, we unraveled an important role of ASIC3 in regulating cardiac autonomic function, whereby loss of ASIC3 alters the normal physiological response to ischemic stimuli, which reveals new implications for therapy in autonomic nervous system-related cardiovascular diseases.

Autonomous Navigation Using Celestial Objects

NASA Technical Reports Server (NTRS)

Folta, David; Gramling, Cheryl; Leung, Dominic; Belur, Sheela; Long, Anne

1999-01-01

In the twenty-first century, National Aeronautics and Space Administration (NASA) Enterprises envision frequent low-cost missions to explore the solar system, observe the universe, and study our planet. Satellite autonomy is a key technology required to reduce satellite operating costs. The Guidance, Navigation, and Control Center (GNCC) at the Goddard Space Flight Center (GSFC) currently sponsors several initiatives associated with the development of advanced spacecraft systems to provide autonomous navigation and control. Autonomous navigation has the potential both to increase spacecraft navigation system performance and to reduce total mission cost. By eliminating the need for routine ground-based orbit determination and special tracking services, autonomous navigation can streamline spacecraft ground systems. Autonomous navigation products can be included in the science telemetry and forwarded directly to the scientific investigators. In addition, autonomous navigation products are available onboard to enable other autonomous capabilities, such as attitude control, maneuver planning and orbit control, and communications signal acquisition. Autonomous navigation is required to support advanced mission concepts such as satellite formation flying. GNCC has successfully developed high-accuracy autonomous navigation systems for near-Earth spacecraft using NASA's space and ground communications systems and the Global Positioning System (GPS). Recently, GNCC has expanded its autonomous navigation initiative to include satellite orbits that are beyond the regime in which use of GPS is possible. Currently, GNCC is assessing the feasibility of using standard spacecraft attitude sensors and communication components to provide autonomous navigation for missions including: libration point, gravity assist, high-Earth, and interplanetary orbits. The concept being evaluated uses a combination of star, Sun, and Earth sensor measurements along with forward-link Doppler measurements from the command link carrier to autonomously estimate the spacecraft's orbit and reference oscillator's frequency. To support autonomous attitude determination and control and maneuver planning and control, the orbit determination accuracy should be on the order of kilometers in position and centimeters per second in velocity. A less accurate solution (one hundred kilometers in position) could be used for acquisition purposes for command and science downloads. This paper provides performance results for both libration point orbiting and high Earth orbiting satellites as a function of sensor measurement accuracy, measurement types, measurement frequency, initial state errors, and dynamic modeling errors.

[Response of pancreatic polypeptide to a protein rich meal in insulin non dependent diabetes melitus and autonomic neuropathy].

PubMed

Kostić, N; Zamaklar, M; Novaković, R; Stajić, S

1994-01-01

Parasympathetic function and plasma hPP response to a protein rich meal were evaluated in 105 insulin non-dependent diabetic patients: 20 with autonomic neuropathy (group A), diagnosed by Clonidin test; 35 patients with neurophysiological evidence of polyneuropath (group B); 30 patients with autonomic neuropathy and polineuropathy (group C), and 20 patients without any sign of neuropathy (group D). Plasma hPP levels were determined by RIA using an anti-hPP antiserum, kindly provided by Prof. S. R. Bloom (Hammersmith Hospital, London). Blood was taken at 0. 45 and 60 minutes after the beginning of the meal. In groups A and C, the meal induced hPP increase was significantly lower than in group D (p 0.001). All group B patients had a marked increase in the peptide, similar to that in diabetics without neuropathy. These result ssuggest that diabetic autonomic neuropathy is associated with dysfunction of hPP secretion, and that the evaluation of hPP response to test meal may be a sensitive and simple method for the assessment of paraympathetic impairment in diabetes.

Diminished autonomic neurocardiac function in patients with generalized anxiety disorder.

PubMed

Kim, Kyungwook; Lee, Seul; Kim, Jong-Hoon

2016-01-01

Generalized anxiety disorder (GAD) is a chronic and highly prevalent disorder that is characterized by a number of autonomic nervous system symptoms. The purpose of this study was to investigate the linear and nonlinear complexity measures of heart rate variability (HRV), measuring autonomic regulation, and to evaluate the relationship between HRV parameters and the severity of anxiety, in medication-free patients with GAD. Assessments of linear and nonlinear complexity measures of HRV were performed in 42 medication-free patients with GAD and 50 healthy control subjects. In addition, the severity of anxiety symptoms was assessed using the State-Trait Anxiety Inventory and Beck Anxiety Inventory. The values of the HRV measures of the groups were compared, and the correlations between the HRV measures and the severity of anxiety symptoms were assessed. The GAD group showed significantly lower standard deviation of RR intervals and the square root of the mean squared differences of successive normal sinus intervals values compared to the control group ( P <0.01). The approximate entropy value, which is a nonlinear complexity indicator, was also significantly lower in the patient group than in the control group ( P <0.01). In correlation analysis, there were no significant correlations between HRV parameters and the severity of anxiety symptoms. The present study indicates that GAD is significantly associated with reduced HRV, suggesting that autonomic neurocardiac integrity is substantially impaired in patients with GAD. Future prospective studies are required to investigate the effects of pharmacological or non-pharmacological treatment on neuroautonomic modulation in patients with GAD.

Metabolic Syndrome and Short-Term Heart Rate Variability in Adults with Intellectual Disabilities

ERIC Educational Resources Information Center

Chang, Yaw-Wen; Lin, Jin-Ding; Chen, Wei-Liang; Yen, Chia-Feng; Loh, Ching-Hui; Fang, Wen-Hui; Wu, Li-Wei

2012-01-01

Metabolic syndrome (MetS) increases the risk of cardiovascular events. Heart rate variability (HRV) represents autonomic functioning, and reduced HRV significantly increases cardiovascular mortality. The aims of the present paper are to assess the prevalence of MetS in adults with intellectual disabilities (ID), the difference in short-term HRV…

Development of Autonomous Aerobraking (Phase 1)

NASA Technical Reports Server (NTRS)

Murri, Daniel G.; Powell, Richard W.; Prince, Jill L.

2012-01-01

The NASA Engineering and Safety Center received a request from Mr. Daniel Murri (NASA Technical Fellow for Flight Mechanics) to develop an autonomous aerobraking capability. An initial evaluation for all phases of this assessment was approved to proceed at the NESC Review Board meeting. The purpose of phase 1 of this study was to provide an assessment of the feasibility of autonomous aerobraking. During this phase, atmospheric, aerodynamic, and thermal models for a representative spacecraft were developed for both the onboard algorithm known as Autonomous Aerobraking Development Software, and a ground-based "truth" simulation developed for testing purposes. The results of the phase 1 assessment are included in this report.

Autonomous motivation and quality of life as predictors of physical activity in patients with schizophrenia.

PubMed

Costa, Raquel; Bastos, Tânia; Probst, Michel; Seabra, André; Vilhena, Estela; Corredeira, Rui

2018-02-08

Being physically active is a complex behaviour in patients with schizophrenia. Several factors were identified as barriers to achieving active behaviours in this population. Therefore, the purpose of this study was to investigate among a number of barriers what predicts the most on physical activity (PA) in patients with schizophrenia. A total of 114 patients (28♀) with schizophrenia were included. Body mass index (BMI) was calculated. Autonomous and controlled motivation (Behavioural Regulation in Exercise Questionnaire - 3), self-esteem (Rosenberg Self-esteem scale), quality of life (World Health Organization Quality of Life Scale - Brief version) and functional exercise capacity (6-minute walk test - 6MWT) were evaluated. Multiple Regression Analysis was applied to assess the effect of these variables on Total PA per week (International Physical Activity Questionnaire - short version). Autonomous motivation and domains of quality of life were positively correlated with Total PA per week. Stepwise multiple regression analyses showed that of all the candidate factors to predict PA, autonomous motivation and global domain of quality of life were found as significant predictors. Our findings help to understand the importance of autonomous motivation and quality of life for PA in patients with schizophrenia. Knowledge about these predictors may provide guidance to improve PA behaviour in this population.

Trait Mindfulness Predicts Attentional and Autonomic Regulation of Alcohol Cue-Reactivity

PubMed Central

Garland, Eric L.

2013-01-01

Background The trait of mindfulness varies among meditation-naïve individuals and is associated with attentional and autonomic regulation, two neurocognitive functions that become impaired in addiction. It was hypothesized that alcohol dependent inpatients with comparatively high levels of trait mindfulness would exhibit significant autonomic recovery from stress-primed alcohol cues mediated by greater attentional disengagement from such cues. Methods 58 alcohol dependent inpatients participated in affect-modulated psychophysiological cue-reactivity protocol and a spatial cueing task designed to assess alcohol attentional bias (AB). Associations between trait mindfulness, alcohol AB, and an index of autonomic activity, high-frequency heart rate variability (HFHRV), were examined via multivariate path analysis. Results Higher trait mindfulness was significantly associated with less difficulty resisting the urge to drink and greater HFHRV recovery from stress-primed alcohol cues. After statistically controlling for the correlation of mindfulness and perceived difficulty resisting drinking urges, the association between mindfulness and HFHRV recovery was partially mediated by attentional disengagement from alcohol cues (model R2 = .30). Discussion Alcohol dependent inpatients higher in mindfulness are better able to disengage attention from alcohol cues, which in turn predicts the degree of HFHRV recovery from such cues. Trait mindfulness may index cognitive control over appetitive responses reflected in superior attentional and autonomic regulation of stress-primed alcohol cue-reactivity. PMID:23976814

May a unitary autonomic index help assess autonomic cardiac regulation in elite athletes? Preliminary observations on the national Italian Olympic committee team.

PubMed

Sala, Roberto; Malacarne, Mara; Tosi, Fabio; Benzi, Manuela; Solaro, Nadia; Tamorri, Stefano; Spataro, Antonio; Pagani, Massimo; Lucini, Daniela

2017-12-01

Long term endurance training, as occurring in elite athletes, is associated to cardiac neural remodeling in favor of cardioprotective vagal mechanisms, resulting in resting bradycardia and augmented contribution of cardiac parasympathetic nerve activity. Autonomic assessment can be performed by way of heart rate variability. This technique however provides multiple indices, and there is not yet complete agreement on their specific significance. Purpose of the study was to assess whether a rank transformation and radar plot could provide a unitary autonomic index, capable to show a correlation between intensity of individual work and quality of autonomic regulation. We studied 711 (23.6±6.2 years) elite athletes that took part in the selection procedure for the 2016 Rio Olympic Games for the National Italian Olympic Committee (CONI). Indices from Heart Rate Variability HRV obtained at rest, during standing up and during recovery from an exercise test were used to compute a percent ranked unitary autonomic index for sport (ANSIs), taken as proxy of quality of autonomic regulation. Within the observed wide range of energy expenditure, the unitary autonomic index ANSIs appears significantly correlated to individual and discipline specific training workloads (r=0.25, P<0.001 and r=0.78, P<0.001, respectively), correcting for possible age and gender bias. ANSIs also positively correlates to lipid profile. Estimated intensity of physical activity correlates with quality of cardiac autonomic regulation, as expressed by a novel unitary index of cardiac autonomic regulation. ANSIs could provide a novel and convenient approach to individual autonomic evaluation in athletes.

Frequency analysis of heart rate variability: a useful assessment tool of linearly polarized near-infrared irradiation to stellate ganglion area for burning mouth syndrome.

PubMed

Momota, Yukihiro; Takano, Hideyuki; Kani, Koichi; Matsumoto, Fumihiro; Motegi, Katsumi; Aota, Keiko; Yamamura, Yoshiko; Omori, Mayuko; Tomioka, Shigemasa; Azuma, Masayuki

2013-03-01

Burning mouth syndrome (BMS) is characterized by the following subjective complaints without distinct organic changes: burning sensation in mouth or chronic pain of tongue. BMS is also known as glossodynia; both terms are used equivalently in Japan. Although the real cause of BMS is still unknown, it has been pointed out that BMS is related to some autonomic abnormality, and that stellate ganglion near-infrared irradiation (SGR) corrects the autonomic abnormality. Frequency analysis of heart rate variability (HRV) is expected to be useful for assessing autonomic abnormality. This study investigated whether frequency analysis of HRV could reveal autonomic abnormality associated with BMS, and whether autonomic changes were corrected after SGR. Eight subjects received SGR; the response to SGR was assessed by frequency analysis of HRV. No significant difference of autonomic activity concerning low-frequency (LF) norm, high-frequency (HF) norm, and low-frequency/high-frequency (LF/HF) was found between SGR effective and ineffective groups. Therefore, we proposed new parameters: differential normalized low frequency (D LF norm), differential normalized high frequency (D HF norm), and differential low-frequency/high-frequency (D LF/HF), which were defined as differentials between original parameters just before and after SGR. These parameters as indexes of responsiveness of autonomic nervous system (ANS) revealed autonomic changes in BMS, and BMS seems to be related to autonomic instability rather than autonomic imbalance. Frequency analysis of HRV revealed the autonomic instability associated with BMS and enabled tracing of autonomic changes corrected with SGR. It is suggested that frequency analysis of HRV is very useful in follow up of BMS and for determination of the therapeutic efficacy of SGR. Wiley Periodicals, Inc.

Effects of aerobic or resistance exercise training on cardiovascular autonomic function of subjects with type 2 diabetes: A pilot study.

PubMed

Bellavere, F; Cacciatori, V; Bacchi, E; Gemma, M L; Raimondo, D; Negri, C; Thomaseth, K; Muggeo, M; Bonora, E; Moghetti, P

2018-03-01

Both aerobic (AER) and resistance (RES) training improve metabolic control in patients with type 2 diabetes (T2DM). However, information on the effects of these training modalities on cardiovascular autonomic control is limited. Our aim was to compare the effects of AER and RES training on cardiovascular autonomic function in these subjects. Cardiovascular autonomic control was assessed by Power Spectral Analysis (PSA) of Heart Rate Variability (HRV) and baroreceptors function indexes in 30 subjects with T2DM, randomly assigned to aerobic or resistance training for 4 months. In particular, PSA of HRV measured the Low Frequency (LF) and High Frequency (HF) bands of RR variations, expression of prevalent sympathetic and parasympathetic drive, respectively. Furthermore, we measured the correlation occurring between systolic blood pressure and heart rate during a standardized Valsalva maneuver using two indexes, b2 and b4, considered an expression of baroreceptor sensitivity and peripheral vasoactive adaptations during predominant sympathetic and parasympathetic drive, respectively. After training, the LF/HF ratio, which summarizes the sympatho-vagal balance in HRV control, was similarly decreased in the AER and RES groups. After AER, b2 and b4 significantly improved. After RES, changes of b2 were of borderline significance, whereas changes of b4 did not reach statistical significance. However, comparison of changes in baroreceptor sensitivity indexes between groups did not show statistically significant differences. Both aerobic and resistance training improve several indices of the autonomic control of the cardiovascular system in patients with T2DM. Although these improvements seem to occur to a similar extent in both training modalities, some differences cannot be ruled out. NCT01182948, clinicaltrials.gov. Copyright © 2017 The Italian Society of Diabetology, the Italian Society for the Study of Atherosclerosis, the Italian Society of Human Nutrition, and the Department of Clinical Medicine and Surgery, Federico II University. Published by Elsevier B.V. All rights reserved.

Central hyperadrenergic state after lightning strike.

PubMed

Parsaik, Ajay K; Ahlskog, J Eric; Singer, Wolfgang; Gelfman, Russell; Sheldon, Seth H; Seime, Richard J; Craft, Jennifer M; Staab, Jeffrey P; Kantor, Birgit; Low, Phillip A

2013-08-01

To describe and review autonomic complications of lightning strike. Case report and laboratory data including autonomic function tests in a subject who was struck by lightning. A 24-year-old man was struck by lightning. Following that, he developed dysautonomia, with persistent inappropriate sinus tachycardia and autonomic storms, as well as posttraumatic stress disorder (PTSD) and functional neurologic problems. The combination of persistent sinus tachycardia and episodic exacerbations associated with hypertension, diaphoresis, and agitation was highly suggestive of a central hyperadrenergic state with superimposed autonomic storms. Whether the additional PTSD and functional neurologic deficits were due to a direct effect of the lightning strike on the central nervous system or a secondary response is open to speculation.

Central Hyperadrenergic State After Lightning Strike

PubMed Central

Parsaik, Ajay K.; Ahlskog, J. Eric; Singer, Wolfgang; Gelfman, Russell; Sheldon, Seth H.; Seime, Richard J.; Craft, Jennifer M.; Staab, Jeffrey P.; Kantor, Birgit; Low, Phillip A.

2013-01-01

Objective To describe and review autonomic complications of lightning strike. Methods Case report and laboratory data including autonomic function tests in a subject who was struck by lightning. Results A 24-year-old man was struck by lightning. Following that, he developed dysautonomia, with persistent inappropriate sinus tachycardia and autonomic storms, as well as posttraumatic stress disorder (PTSD) and functional neurologic problems. Interpretation The combination of persistent sinus tachycardia and episodic exacerbations associated with hypertension, diaphoresis, and agitation were highly suggestive of a central hyperadrenergic state with superimposed autonomic storms. Whether the additional PTSD and functional neurologic deficits were due to a direct effect of the lightning strike on the CNS or a secondary response is open to speculation. PMID:23761114

TRPA1 mediates changes in heart rate variability and cardiac mechanical function in mice exposed to acrolein

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

Kurhanewicz, Nicole

Short-term exposure to ambient air pollution is linked with adverse cardiovascular effects. While previous research focused primarily on particulate matter-induced responses, gaseous air pollutants also contribute to cause short-term cardiovascular effects. Mechanisms underlying such effects have not been adequately described, however the immediate nature of the response suggests involvement of irritant neural activation and downstream autonomic dysfunction. Thus, this study examines the role of TRPA1, an irritant sensory receptor found in the airways, in the cardiac response of mice to acrolein and ozone. Conscious unrestrained wild-type C57BL/6 (WT) and TRPA1 knockout (KO) mice implanted with radiotelemeters were exposed once tomore » 3 ppm acrolein, 0.3 ppm ozone, or filtered air. Heart rate (HR) and electrocardiogram (ECG) were recorded continuously before, during and after exposure. Analysis of ECG morphology, incidence of arrhythmia and heart rate variability (HRV) were performed. Cardiac mechanical function was assessed using a Langendorff perfusion preparation 24 h post-exposure. Acrolein exposure increased HRV independent of HR, as well as incidence of arrhythmia. Acrolein also increased left ventricular developed pressure in WT mice at 24 h post-exposure. Ozone did not produce any changes in cardiac function. Neither gas produced ECG effects, changes in HRV, arrhythmogenesis, or mechanical function in KO mice. These data demonstrate that a single exposure to acrolein causes cardiac dysfunction through TRPA1 activation and autonomic imbalance characterized by a shift toward parasympathetic modulation. Furthermore, it is clear from the lack of ozone effects that although gaseous irritants are capable of eliciting immediate cardiac changes, gas concentration and properties play important roles. - Highlights: • Acute acrolein exposure causes autonomic imbalance and altered CV function in mice. • TRPA1 mediates acrolein-induced autonomic nervous system cardiac effects. • Sensory irritation contributes to acrolein-induced cardiac arrhythmia & dysfunction.« less

Cardiovascular autonomic dysfunction and carotid stiffness in adults with repaired tetralogy of Fallot.

PubMed

Novaković, Marko; Prokšelj, Katja; Starc, Vito; Jug, Borut

2017-06-01

Adults after surgical repair of tetralogy of Fallot (ToF) may have impaired vascular and cardiac autonomic function. Thus, we wanted to assess interrelations between heart rate variability (HRV) and heart rate recovery (HRR), as parameters of cardiac autonomic function, and arterial stiffness, as a parameter of vascular function, in adults with repaired ToF as compared to healthy controls. In a case-control study of adults with repaired ToF and healthy age-matched controls we measured: 5-min HRV variability (with time and frequency domain data collected), carotid artery stiffness (through pulse-wave analysis using echo-tracking ultrasound) and post-exercise HRR (cycle ergometer exercise testing). Twenty-five patients with repaired ToF (mean age 38 ± 10 years) and 10 healthy controls (mean age 39 ± 8 years) were included. Selected HRR and HRV (time-domain) parameters, but not arterial stiffness were significantly reduced in adults after ToF repair. Moreover, a strong association between late/slow HRR (after 2, 3 and 4 min) and carotid artery stiffness was detected in ToF patients (r = -0.404, p = 0.045; r = -0.545, p = 0.005 and r = -0.545, p = 0.005, respectively), with statistical significance retained even after adjusting for age, gender, resting heart rate and β-blockers use (r = -0.393, p = 0.024 for HRR after 3 min). Autonomic cardiac function is impaired in patients with repaired ToF, and independently associated with vascular function in adults after ToF repair, but not in age-matched healthy controls. These results might help in introducing new predictors of cardiovascular morbidity in a growing population of adults after surgical repair of ToF.

The influence of environmental factors on heart rate chronostructure depending on the individual characteristics of autonomic regulation. Results of long-term medical-ecological studies.

NASA Astrophysics Data System (ADS)

Isaeva, Olga; Zenchenko, Tatiana; Breus, Tamara; Chernikova, Anna; Baevsky, Roman

It was previously shown [Baevsky, Petrov, 1998] that during space flight under influence of geomagnetic disturbances there are both specific response of the autonomic regulation system in the form of vasomotor cardiovascular center activation (LF spectral components) and non-specific stress response, which depends on the actual autonomic balance [Breus, Baevsky, 2002]. Within the project "Mars-500" the parallel medical-ecological studies were conducted in 10 groups (10-16 people), that lived in different regions of the world under the influence of various environmental factors - climatic, geographic, industrial, social and other. It allowed us to obtain a sufficiently large number of variants of adaptive reactions caused by differences in external impacts. The main research method was the heart rate variability (HRV) analysis in short ECG samples (5 minutes) for assessing heart rate chronostructure and functional status of autonomic regulation. Results of studies have demonstrated that environmental loads on the regulatory mechanisms is higher in the northern and north-eastern regions of Russia - Magadan and Syktyvkar. Stress-index of regulatory systems and adaptive risk indicator is significantly higher in these groups [Baevsky, Berseneva, 2013]. The preliminary search of weather factors (atmospheric pressure, air temperature, humidity and magnetic index Kp) influence on the autonomic regulation of heart rate showed that there are no any significant changes and relationships in the entire group of participants. We have assumed that the character of adaptive responses, including responses to changing weather and geomagnetic conditions, is associated with the individual characteristics and the initial functional state of autonomic regulation. To test this hypothesis, we have identified two groups of subjects with different autonomic balance. The first group included individuals with a pronounced predominance of sympathetic regulation (n = 127), the second - with a strong predominance of parasympathetic activity (n = 64). The analysis of correlations between weather and heart rate chronostructure and functional condition of autonomic regulation revealed that attitude of low frequency (LF) and high frequency (HF) of heart rhythm spectrum higher in both groups at declining geomagnetic activity and lower at its growth. The comparison of other HRV indicators at decreasing and increasing geomagnetic activity displayed the opposite trends in these groups. Stress-index of regulatory systems (SI), which reflects the sympathetic activity, rises in group with sympathetic dominance at reducing geomagnetic activity, and at its growth - in group with parasympathetic dominance. So, we can see that specific adaptive reaction as response to changing geomagnetic situation, which manifested in activation of vasomotor cardiovascular center, is the similar in subjects with different autonomic balance. Non-specific component depends on initial dominance of one or another regulatory mechanism.

Association between respiratory mechanics and autonomic function in morbid obesity.

PubMed

Sant' Anna, M; Carvalhal, R F; Carneiro, J R I; Lapa, M S; Zin, W A; Lugon, J R; Guimarães, F S

2014-01-01

This study aimed to investigate the association between respiratory mechanics and autonomic modulation in morbidly obese patients. We evaluated 10 morbidly obese subjects (BMI=52.9±11.2kg/m(2)), aged 23-58 years. Assessment of respiratory mechanics was done by the forced oscillation technique (FOT), and cardiovascular autonomic function was recorded by heart rate variability analysis (HRV). The Pearson correlation coefficient was used to test the associations between respiratory mechanics and HRV variables. There were associations between the standard deviation of all RR intervals (SDNN) and airway resistance (Rm) (r=-0.82; p=0.004), SDNN and respiratory system resistance (R0) (r=-0.79; p=0.006), root mean square of successive differences between adjacent normal RR intervals (rMSSD) and respiratory system resistance (R5) (r=-0.643; p=0.0451), rMSSD and R0 (r=-0.64; p=0.047), and rMSSD and Rm (r=-0.658; p=0.039). We concluded that the airway and respiratory system resistances are negatively associated with parasympathetic activity in patients with morbid obesity. Copyright © 2013 Sociedade Portuguesa de Pneumologia. Published by Elsevier España. All rights reserved.

Prevalence and pattern of cardiac autonomic dysfunction in newly detected type 2 diabetes mellitus.

PubMed

Jyotsna, Viveka P; Sahoo, Abhay; Sreenivas, V; Deepak, K K

2009-01-01

Cardiac autonomic functions were assessed in 145 consecutive recently detected type 2 diabetics. Ninety-nine healthy persons served as controls. Criteria for normalcy were, heart rate variation during deep breathing >or=15 beats/min, deep breathing expiratory to inspiratory R-R ratio >or=1.21, Valsalva ratio >or=1.21, sustained handgrip test >or=16 mm of mercury, cold pressor test >or=10, BP response to standing or=1.04. An abnormal test was defined as the above parameters being <10 beats/min, <1.21, <1.21, or=30 mm of mercury and

Neurotoxic impact of mercury on the central nervous system evaluated by neuropsychological tests and on the autonomic nervous system evaluated by dynamic pupillometry.

PubMed

Milioni, Ana Luiza V; Nagy, Balázs V; Moura, Ana Laura A; Zachi, Elaine C; Barboni, Mirella T S; Ventura, Dora F

2017-03-01

Mercury vapor is highly toxic to the human body. The present study aimed to investigate the occurrence of neuropsychological dysfunction in former workers of fluorescent lamps factories that were exposed to mercury vapor (years after cessation of exposure), diagnosed with chronic mercurialism, and to investigate the effects of such exposure on the Autonomic Nervous System (ANS) using the non-invasive method of dynamic pupillometry. The exposed group and a control group matched by age and educational level were evaluated by the Beck Depression Inventory and with the computerized neuropsychological battery CANTABeclipse - subtests of working memory (Spatial Span), spatial memory (Spatial Recognition Memory), visual memory (Pattern Recognition Memory) and action planning (Stockings of Cambridge). The ANS was assessed by dynamic pupillometry, which provides information on the operation on both the sympathetic and parasympathetic functions. Depression scores were significantly higher among the former workers when compared with the control group. The exposed group also showed significantly worse performance in most of the cognitive functions assessed. In the dynamic pupillometry test, former workers showed significantly lower response than the control group in the sympathetic response parameter (time of 75% of pupillary recovery at 10cd/m 2 luminance). Our study found indications that are suggestive of cognitive deficits and losses in sympathetic autonomic activity among patients occupationally exposed to mercury vapor. Copyright © 2016 Elsevier B.V. All rights reserved.

Effects of acute beta-adrenergic antagonism on verbal problem solving in autism spectrum disorder and exploration of treatment response markers.

PubMed

Zamzow, Rachel M; Ferguson, Bradley J; Ragsdale, Alexandra S; Lewis, Morgan L; Beversdorf, David Q

2017-08-01

Autism spectrum disorder (ASD) is characterized by impairments in social communication as well as restricted, repetitive behaviors. Evidence suggests that some individuals with ASD have cognitive impairments related to weak central coherence and hyperrestricted processing. Reducing noradrenergic activity may improve aspects of network processing and thus improve cognitive abilities, such as verbal problem solving, in individuals with ASD. The present pilot study explores the effects of acute administration of the beta-adrenergic antagonist propranolol on verbal problem solving in adults and adolescents with ASD. In a within-subject crossover-design, 20 participants with ASD received a single dose of propranolol or placebo on one of two sessions in a double-blinded, counterbalanced manner. Verbal problem solving was assessed via an anagram task. Baseline measurements of autonomic nervous system functioning were obtained, and anxiety was assessed at baseline and following drug administration. Participants solved the anagrams more quickly in the propranolol condition, as compared to the placebo condition, suggesting a potential cognitive benefit of this agent. Additionally, we observed a negative linear relationship between response to propranolol on the anagram task and two measures of baseline autonomic activity, as well as a positive linear relationship between drug response and baseline anxiety. These relationships propose potential markers for treatment response, as propranolol influences both autonomic functioning and anxiety. Further investigation is needed to expand on the present single-dose psychopharmacological challenge and explore the observed effects of propranolol in a serial-dose setting.

Clinical findings associated with cardiovascular autonomic dysfunction in adult sickle cell anaemia patients.

PubMed

Oguanobi, Nelson I; Onwubere, Basden J C; Anisiuba, Benedict C; Ike, Samuel O; Ejim, Emmanuel C; Ibegbulam, Obike G

2012-04-01

Involvement of the cardiovascular autonomic nervous system in various diseases is often associated with increased morbidity and mortality. The objective of this study was to examine the clinical features associated with cardiovascular autonomic neuropathy (CAN) in adult Nigerians with sickle cell anaemia. A cross-sectional study was carried out on 62 steady state sickle cell anaemia patients recruited from the adult out-patient clinic. Cardiovascular autonomic dysfunction was determined based on abnormal values in at least two of five non-invasive tests: Valsalva manoeuvre, heart rate variation during deep breathing, heart rate response to standing, blood pressure response to sustained handgrip, and blood pressure response to standing. All the subjects were initially evaluated in the clinic for symptoms of cardiovascular disease and peripheral vascular disease, and then clinically examined to assess their cardiovascular and neurological status at rest. Out of the 44 patients with cardiovascular autonomic neuropathy 23 were males, while 21 were females. The mean ages were 28.3 +/- 5.8 y for patients with CAN and 28.0 +/- 5.0 y for patients without CAN (P = 0.817). Sickle cell anaemia patients with CAN had significantly lower ankle systolic blood pressure, reduced ankle brachial blood pressure index, mean arterial blood pressure and haematocrit than patients without CAN. Of all the variables evaluated leg ulcers, postural dizziness, erectile dysfunction in men, and history of recurrent acute chest syndromes were found significantly more in patients with CAN than without. Clinical abnormalities tend to worsen with increasing degree of cardiovascular autonomic dysfunction. Significant cardiac morbidity is associated with abnormal cardiovascular autonomic function in sickle cell anaemia.

Postnatal Cardiac Autonomic Nervous Control in Pediatric Congenital Heart Disease

PubMed Central

Nederend, Ineke; Jongbloed, Monique R. M.; de Geus, Eco J. C.; Blom, Nico A.; ten Harkel, Arend D. J.

2016-01-01

Congenital heart disease is the most common congenital defect. During childhood, survival is generally good but, in adulthood, late complications are not uncommon. Abnormal autonomic control in children with congenital heart disease may contribute considerably to the pathophysiology of these long term sequelae. This narrative review of 34 studies aims to summarize current knowledge on function of the autonomic nervous system in children with a congenital heart defect. Large scale studies that measure both branches of the nervous system for prolonged periods of time in well-defined patient cohorts in various phases of childhood and adolescence are currently lacking. Pending such studies, there is not yet a good grasp on the extent and direction of sympathetic and parasympathetic autonomic function in pediatric congenital heart disease. Longitudinal studies in homogenous patient groups linking autonomic nervous system function and clinical outcome are warranted. PMID:29367565

The effects of moclobemide on autonomic and cognitive functions in healthy volunteers.

PubMed

Siepmann, M; Handel, J; Mueck-Weymann, M; Kirch, W

2004-03-01

Moclobemide, a reversible and selective inhibitor of the MAO-A isoenzyme, is marketed as an antidepressant that lacks autonomic and cognitive side effects. However, only few and inconclusive quantitative data on the effects of moclobemide on autonomic and cognitive functions have been reported in the literature. Therefore, a double-blind, randomized, placebo-controlled crossover trial was performed. Twelve healthy male volunteers (age 22-29 years) received orally 150 mg moclobemide b.i.d. and placebo for 14 days each. Heart rate variability (HRV) and skin conductance response (SCR) following sudden deep breath were employed as parameters for autonomic function. Quantitative EEG (qEEG) and psychometric tests served as parameters for cognitive function. Measurements were performed before the start of drug administration and repeatedly on the last treatment day. Parameters of HRV and SCR were not changed by multiple dosing with moclobemide (P > 0.05). Neither cognitive functions such as flicker fusion frequency, memory, choice reaction time, and psychomotor performance nor qEEG was significantly influenced, but subjective tiredness was decreased at all time points of measurement after multiple dosing with moclobemide (P < 0.05). In conclusion, moclobemide does not appear to influence autonomic functions or cognitive functions when given subchronically to healthy humans. In contrast, changes in subjective mood hint at a subtle activating effect.

Women's Sexual Health and Reproductive Function After SCI.

PubMed

Courtois, Frédérique; Alexander, Marcalee; McLain, Amie B Jackson

2017-01-01

Sexual function and to a lesser extent reproduction are often disrupted in women with spinal cord injuries (SCI), who must be educated to better understand their sexual and reproductive health. Women with SCI are sexually active; they can use psychogenic or reflexogenic stimulation to obtain sexual pleasure and orgasm. Treatment should consider a holistic approach using autonomic standards to describe remaining sexual function and to assess both genital function and psychosocial factors. Assessment of genital function should include thoracolumbar dermatomes, vulvar sensitivity (touch, pressure, vibration), and sacral reflexes. Self-exploration should include not only clitoral stimulation, but also stimulation of the vagina (G spot), cervix, and nipples conveyed by different innervation sources. Treatments may consider PDE5 inhibitors and flibanserin on an individual basis, and secondary consequences of SCI should address concerns with spasticity, pain, incontinence, and side effects of medications. Psychosocial issues must be addressed as possible contributors to sexual dysfunctions (eg, lower self-esteem, past sexual history, depression, dating habits). Pregnancy is possible for women with SCI; younger age at the time of injury and at the time of pregnancy being significant predictors of successful pregnancy, along with marital status, motor score, mobility, and occupational scores. Pregnancy may decrease the level of functioning (eg, self-care, ambulation, upper-extremity tasks), may involve complications (eg, decubitus ulcers, weight gain, urological complications), and must be monitored for postural hypotension and autonomic dysreflexia. Taking into consideration the physical and psychosocial determinants of sexuality and childbearing allows women with SCI to achieve positive sexual and reproductive health.

Autonomic control of the heart is altered in Sprague-Dawley rats with spontaneous hydronephrosis

PubMed Central

Arnold, Amy C.; Shaltout, Hossam A.; Gilliam-Davis, Shea; Kock, Nancy D.

2011-01-01

The renal medulla plays an important role in cardiovascular regulation, through interactions with the autonomic nervous system. Hydronephrosis is characterized by substantial loss of renal medullary tissue. However, whether alterations in autonomic control of the heart are observed in this condition is unknown. Thus we assessed resting hemodynamics and baroreflex sensitivity (BRS) for control of heart rate in urethane/chloralose-anesthetized Sprague-Dawley rats with normal or hydronephrotic kidneys. While resting arterial pressure was similar, heart rate was higher in rats with hydronephrosis (290 ± 12 normal vs. 344 ± 11 mild/moderate vs. 355 ± 13 beats/min severe; P < 0.05). The evoked BRS to increases, but not decreases, in pressure was lower in hydronephrotic rats (1.06 ± 0.06 normal vs. 0.72 ± 0.10 mild/moderate vs. 0.63 ± 0.07 ms/mmHg severe; P < 0.05). Spectral analysis methods confirmed reduced parasympathetic function in hydronephrosis, with no differences in measures of indirect sympathetic activity among conditions. As a secondary aim, we investigated whether autonomic dysfunction in hydronephrosis is associated with activation of the renin-angiotensin system (RAS). There were no differences in circulating angiotensin peptides among conditions, suggesting that the impaired autonomic function in hydronephrosis is independent of peripheral RAS activation. A possible site for angiotensin II-mediated BRS impairment is the solitary tract nucleus (NTS). In normal and mild/moderate hydronephrotic rats, NTS administration of the angiotensin II type 1 receptor antagonist candesartan significantly improved the BRS, suggesting that angiotensin II provides tonic suppression to the baroreflex. In contrast, angiotensin II blockade produced no significant effect in severe hydronephrosis, indicating that at least within the NTS baroreflex suppression in these animals is independent of angiotensin II. PMID:21460193

Behavioral Screening for Toxicology | Science Inventory | US ...

EPA Pesticide Factsheets

Screening for behavioral toxicity, or neurotoxicity, has been in use for decades; however, only in the past 20 years has this become a standard practice in toxicology. Current screening batteries, such as the functional observational battery (FOB), are derived from protocols used in pharmacology, toxicology, and psychology. Although there is a range of protocols in use today, all focus on detailed observations and specific tests of reflexes and responses. Several neurological functions are typically assessed, including autonomic, neuromuscular, and sensory, as well as levels of activity and excitability. The tests have been shown to be valid in detecting expected effects of known neurotoxicants, and reliable and reproducible whn compared across laboratories. Regardless of the specific protocol used, proper conduct and statistical analyses of the data are critical. Interpretation is based on the information from individual end points as well as the profile, or pattern, of effects observed. As long as continual refinements are made, behavioral screening methods will continue to be important tools with which to protect human health in the future.autonomic function; behavior; behavioral phenotypes; behavioral toxicity; excitability; functional observational battery ; motor activity; mouse; neuromuscular function; positive controls; rat; screening battery ; sensory function Screening for behavioral toxicity, or neurotoxicity, has been in use for decades; how

Developmental changes in autonomic responses are associated with future reward/punishment expectations: A study of sympathetic skin responses in the Markov decision task.

PubMed

Hosaka, Hiromi; Aoyagi, Kakuro; Kaga, Yoshimi; Kanemura, Hideaki; Sugita, Kanji; Aihara, Masao

2017-08-01

Autonomic nervous system activity is recognized as a major component of emotional responses. Future reward/punishment expectations depend upon the process of decision making in the frontal lobe, which is considered to play an important role in executive function. The aim of this study was to investigate the relationship between autonomic responses and decision making during reinforcement tasks using sympathetic skin responses (SSR). Nine adult and 9 juvenile (mean age, 10.2years) volunteers were enrolled in this study. SSRs were measured during the Markov decision task (MDT), which is a reinforcement task. In this task, subjects must endure a small immediate loss to ultimately get a large reward. The subjects had to undergo three sets of tests and their scores in these tests were assessed and evaluated. All adults showed gradually increasing scores for the MDT from the first to third set. As the trial progressed from the first to second set in adults, SSR appearance ratios remarkably increased for both punishment and reward expectations. In comparison with adults, children showed decreasing scores from the first to second set. There were no significant inter-target differences in the SSR appearance ratio in the first and second set in children. In the third set, the SSR appearance ratio for reward expectations was higher than that in the neutral condition. In reinforcement tasks, such as MDT, autonomic responses play an important role in decision making. We assume that SSRs are elicited during efficient decision making tasks associated with future reward/punishment expectations, which demonstrates the importance of autonomic function. In contrast, in children around the age of 10years, the autonomic system does not react as an organized response specific to reward/punishment expectations. This suggests the immaturity of the future reward/punishment expectations process in children. Copyright © 2017 The Japanese Society of Child Neurology. Published by Elsevier B.V. All rights reserved.

Autonomic nervous system function in young children with functional abdominal pain or irritable bowel syndrome

USDA-ARS?s Scientific Manuscript database

Adults with irritable bowel syndrome (IBS) have been reported to have alterations in autonomic nervous system function as measured by vagal activity via heart rate variability. Whether the same is true for children is unknown. We compared young children 7 to 10 years of age with functional abdominal...

Altered Behavioral and Autonomic Pain Responses in Alzheimer’s Disease Are Associated with Dysfunctional Affective, Self-Reflective and Salience Network Resting-State Connectivity

PubMed Central

Beach, Paul A.; Huck, Jonathan T.; Zhu, David C.; Bozoki, Andrea C.

2017-01-01

While pain behaviors are increased in Alzheimer’s disease (AD) patients compared to healthy seniors (HS) across multiple disease stages, autonomic responses are reduced with advancing AD. To better understand the neural mechanisms underlying these phenomena, we undertook a controlled cross-sectional study examining behavioral (Pain Assessment in Advanced Dementia, PAINAD scores) and autonomic (heart rate, HR) pain responses in 24 HS and 20 AD subjects using acute pressure stimuli. Resting-state fMRI was utilized to investigate how group connectivity differences were related to altered pain responses. Pain behaviors (slope of PAINAD score change and mean PAINAD score) were increased in patients vs. controls. Autonomic measures (HR change intercept and mean HR change) were reduced in severe vs. mildly affected AD patients. Group functional connectivity differences associated with greater pain behavior reactivity in patients included: connectivity within a temporal limbic network (TLN) and between the TLN and ventromedial prefrontal cortex (vmPFC); between default mode network (DMN) subcomponents; between the DMN and ventral salience network (vSN). Reduced HR responses within the AD group were associated with connectivity changes within the DMN and vSN—specifically the precuneus and vmPFC. Discriminant classification indicated HR-related connectivity within the vSN to the vmPFC best distinguished AD severity. Thus, altered behavioral and autonomic pain responses in AD reflects dysfunction of networks and structures subserving affective, self-reflective, salience and autonomic regulation. PMID:28959201

Smart Ultrasound Remote Guidance Experiment (SURGE)- Concept of Operations Evaluation for Using Remote Guidance Ultrasound for Planetary Space Flight

NASA Technical Reports Server (NTRS)

Hurst, Victor, IV; Peterson, Sean; Garcia, Kathleen; Sargsyan, Ashot; Ebert, Douglas; Ham, David; Amponsah, David; Dulchavsky, Scott

2010-01-01

Introduction Use of remote guidance (RG) techniques aboard the International Space Station (ISS) has enabled astronauts to collect diagnostic-level ultrasound images. Exploration class missions will require this cohort of (typically) non-formally trained sonographers to operate with greater autonomy given the longer communication delays (2 seconds for ISS vs. >6 seconds for missions beyond the Moon) and communication blackouts. To determine the feasibility and training requirements for autonomous ultrasound image collection by non-expert ultrasound operators, ultrasound images were collected from a similar cohort using three different image collection protocols: RG only, RG with a computer-based learning tool (LT), and autonomous image collection with LT. The groups were assessed for both image quality and time to collect the images. Methods Subjects were randomized into three groups: RG only, RG with LT, and autonomous with LT. Each subject received 10 minutes of standardized training before the experiment. The subjects were tasked with making the following ultrasound assessments: 1) bone fracture and 2) focused assessment with sonography in trauma (FAST) to assess a patient s abdomen. Human factors-related questionnaire data were collected immediately after the assessments. Results The autonomous group did not out-perform the two groups that received RG. The mean time for the autonomous group to collect images was less than the RG groups, however the mean image quality for the autonomous group was less compared to both RG groups. Discussion Remote guidance continues to produce higher quality ultrasound images than autonomous ultrasound operation. This is likely due to near-instant feedback on image quality from the remote guider. Expansion in communication time delays, however, diminishes the capability to provide this feedback, thus requiring more autonomous ultrasound operation. The LT has the potential to be an excellent training and coaching component for autonomous ultrasound image collection during exploration missions.

Effects of reward and punishment on task performance, mood and autonomic nervous function, and the interaction with personality.

PubMed

Sakuragi, Sokichi; Sugiyama, Yoshiki

2009-06-01

The effects of reward and punishment are different, and there are individual differences in sensitivity to reward and punishment. The purpose of this study was to investigate the effects of reward and punishment on task performance, mood, and autonomic nervous function, along with the interaction with personality. Twenty-one healthy female subjects volunteered for the experiment. The task performance was evaluated by required time and total errors while performing a Wisconsin Card Sorting Test. We assessed their personalities using the Minnesota Multiphasic Personality Inventory (MMPI) questionnaire, and mood states by a profile of mood states. Autonomic nervous function was estimated by a spectral analysis of heart rate variability, baroreflex sensitivity, and blood pressure. Repeated measures analysis of variance (ANOVA) revealed significant interaction of condition x time course on mood and autonomic nervous activity, which would indicate a less stressed state under the rewarding condition, but revealed no significant interaction of condition x time course on the task performance. The interactions with personality were further analyzed by repeated measures ANOVA applying the clinical scales of MMPI as independent variables, and significant interactions of condition x time course x Pt (psychasthenia) on task performance, mood, and blood pressure, were revealed. That is, the high Pt group, whose members tend to be sensitive and prone to worry, showed gradual improvement of task performance under the punishing situation with slight increase in systolic blood pressure, while showed no improvement under the rewarding situation with fatigue sense attenuation. In contrast, the low Pt group, whose members tend to be adaptive and self-confident, showed gradual improvement under the rewarding situation. Therefore, we should carefully choose the strategy of reward or punishment, considering the interaction with personality as well as the context in which it is given.

Role of Autonomic Reflex Arcs in Cardiovascular Responses to Air Pollution Exposure

PubMed Central

Hazari, Mehdi S.; Farraj, Aimen K.

2016-01-01

The body responds to environmental stressors by triggering autonomic reflexes in the pulmonary receptors, baroreceptors, and chemoreceptors to maintain homeostasis. Numerous studies have shown that exposure to various gases and airborne particles can alter the functional outcome of these reflexes, particularly with respect to the cardiovascular system. Modulation of autonomic neural input to the heart and vasculature following direct activation of sensory nerves in the respiratory system, elicitation of oxidative stress and inflammation, or through other mechanisms is one of the primary ways that exposure to air pollution affects normal cardiovascular function. Any homeostatic process that utilizes the autonomic nervous system to regulate organ function might be affected. Thus, air pollution and other inhaled environmental irritants have the potential to alter both local airway function and baro-and chemoreflex responses, which modulate autonomic control of blood pressure and detect concentrations of key gases in the body. While each of these reflex pathways causes distinct responses, the systems are heavily integrated and communicate through overlapping regions of the brainstem to cause global effects. This short review summarizes the function of major pulmonary sensory receptors, baroreceptors, and carotid body chemoreceptors and discusses the impacts of air pollution exposure on these systems. PMID:25123706

THE EFFECTS OF NON-FUNCTIONAL OVERREACHING AND OVERTRAINING ON AUTONOMIC NERVOUS SYSTEM FUNCTION IN HIGHLY TRAINED ATHLETES.

PubMed

Kajaia, T; Maskhulia, L; Chelidze, K; Akhalkatsi, V; Kakhabrishvili, Z

2017-03-01

Aim of the study was to compare the ANS functioning, as measured by heart rate variability (HRV), in athletes with non-functional overreaching (NFO) and overtraining syndrome (OTS) and in athletes without NFO/OTS. In 43 athletes with NFO/OTS, 40 athletes without NFO/OTS, as well as in 35 sedentary subjects the ANS function was evaluated with the Autonomic Balance Test, based on the HRV analysis of resting heart rate recordings. Results of the study show lower HRV and lower vagal influence along with increased sympathetic cardiovascular control in athletes with non-functional overreaching and particularly in athletes with overtraining, than in highly trained athletes without NFO/OTS. "Stress Response" in athletes with NFO, as well as in some athletes with OTS, showing sympathetic dominance, considered as a sign of physical or mental fatigue and chronic stress, whereas "Total Autonomic Dystonia" in most of the athletes with OTS (67%) reflects more advanced stage of maladaptation associated with depressed regulatory function of the ANS, both sympathetic, as well as vagal influences. Most frequently NFO and OTS were seen in wrestling, which needs further investigation and regular medical monitoring. Thus, results of the study show progression of autonomic imbalance and depression of regulatory function of the autonomic nervous system in athletes with OTS. The cardiac autonomic imbalance observed in overtrained athletes implies changes in HRV and therefore would consider that heart rate variability may provide useful information in detection of overtraining in athletes and can be a valuable adjacent tool for optimising athlete's training program as well as for timely diagnosis and prevention of progression of NFO/OTS.

Connected and autonomous vehicles 2040 vision.

DOT National Transportation Integrated Search

2014-07-01

The Pennsylvania Department of Transportation (PennDOT) commissioned a one-year project, Connected and Autonomous : Vehicles 2040 Vision, with researchers at Carnegie Mellon University (CMU) to assess the implications of connected and : autonomous ve...

Zolpidem arousing effect in persistent vegetative state patients: autonomic, EEG and behavioral assessment.

PubMed

Machado, Calixto; Estévez, Mario; Rodríguez, Rafael; Pérez-Nellar, Jesús; Chinchilla, Mauricio; DeFina, Philip; Leisman, Gerry; Carrick, Frederick R; Melillo, Robert; Schiavi, Adam; Gutiérrez, Joel; Carballo, Maylén; Machado, Andrés; Olivares, Ana; Pérez-Cruz, Nuvia

2014-01-01

To study the Zolpidem arousing effect in persistent vegetative state (PVS) patients combining clinical evaluation, autonomic assessment by heart rate variability (HRV), and EEG records. We studied a group of 8 PVS patients and other 8 healthy control subjects, matched by age and gender. The patients and controls received drug or placebo in two experimental sessions, separated by 10-14 days. The first 30 minutes of the session were considered the basal record, and then Zolpidem was administered. All participants were evaluated clinically, by EEG, and by HRV during the basal record, and for 90 minutes after drug intake. We found in all patients, time-related arousing signs after Zolpidem intake: behavioral (yawns and hiccups), activation of EEG cortical activity, and a vagolytic chronotropic effect without a significant increment of the vasomotor sympathetic tone. We demonstrated time-related arousing signs after Zolpidem intake. We discussed possible mechanisms to explain these patho-physiological findings regarding EEG cortical activation and an autonomic vagolytic drug effect. As this autonomic imbalance might induce cardiocirculatory complications, which we didn't find in any of our patients, we suggest developing future trials under control of physiological indices by bedside monitoring. However, considering that this arousing Zolpidem effect might be certainly related to brain function improvement, it should be particularly considered for the development of new neuro-rehabilitation programs in PVS cases. According to the literature review, we claim that this is the first report about the vagolitic effect of Zolpidem in PVS cases.

Association Between Autonomic Impairment and Structural Deficit in Parkinson Disease

PubMed Central

Chen, Meng-Hsiang; Lu, Cheng-Hsien; Chen, Pei-Chin; Tsai, Nai-Wen; Huang, Chih-Cheng; Chen, Hsiu-Ling; Yang, I-Hsiao; Yu, Chiun-Chieh; Lin, Wei-Che

2016-01-01

Abstract Patients with Parkinson disease (PD) have impaired autonomic function and altered brain structure. This study aimed to evaluate the relationship of gray matter volume (GMV) determined by voxel-based morphometry (VBM) to autonomic impairment in patients with PD. Whole-brain VBM analysis was performed on 3-dimensional T1-weighted images in 23 patients with PD and 15 sex- and age-matched healthy volunteers. The relationship of cardiovascular autonomic function (determined by survey) to baroreflex sensitivity (BRS) (determined from changes in heart rate and blood pressure during the early phase II of the Valsalva maneuver) was tested using least-squares regression analysis. The differences in GMV, autonomic parameters, and clinical data were correlated after adjusting for age and sex. Compared with controls, patients with PD had low BRS, suggesting worse cardiovascular autonomic function, and smaller GMV in several brain locations, including the right amygdala, left hippocampal formation, bilateral insular cortex, bilateral caudate nucleus, bilateral cerebellum, right fusiform, and left middle frontal gyri. The decreased GMVs of the selected brain regions were also associated with increased presence of epithelial progenitor cells (EPCs) in the circulation. In patients with PD, decrease in cardiovascular autonomic function and increase in circulating EPC level are associated with smaller GMV in several areas of the brain. Because of its possible role in the modulation of the circulatory EPC pool and baroreflex control, the left hippocampal formation may be a bio-target for disease-modifying therapy and treatment monitoring in PD. PMID:26986144

Association Between Autonomic Impairment and Structural Deficit in Parkinson Disease.

PubMed

Chen, Meng-Hsiang; Lu, Cheng-Hsien; Chen, Pei-Chin; Tsai, Nai-Wen; Huang, Chih-Cheng; Chen, Hsiu-Ling; Yang, I-Hsiao; Yu, Chiun-Chieh; Lin, Wei-Che

2016-03-01

Patients with Parkinson disease (PD) have impaired autonomic function and altered brain structure. This study aimed to evaluate the relationship of gray matter volume (GMV) determined by voxel-based morphometry (VBM) to autonomic impairment in patients with PD. Whole-brain VBM analysis was performed on 3-dimensional T1-weighted images in 23 patients with PD and 15 sex- and age-matched healthy volunteers. The relationship of cardiovascular autonomic function (determined by survey) to baroreflex sensitivity (BRS) (determined from changes in heart rate and blood pressure during the early phase II of the Valsalva maneuver) was tested using least-squares regression analysis. The differences in GMV, autonomic parameters, and clinical data were correlated after adjusting for age and sex. Compared with controls, patients with PD had low BRS, suggesting worse cardiovascular autonomic function, and smaller GMV in several brain locations, including the right amygdala, left hippocampal formation, bilateral insular cortex, bilateral caudate nucleus, bilateral cerebellum, right fusiform, and left middle frontal gyri. The decreased GMVs of the selected brain regions were also associated with increased presence of epithelial progenitor cells (EPCs) in the circulation. In patients with PD, decrease in cardiovascular autonomic function and increase in circulating EPC level are associated with smaller GMV in several areas of the brain. Because of its possible role in the modulation of the circulatory EPC pool and baroreflex control, the left hippocampal formation may be a bio-target for disease-modifying therapy and treatment monitoring in PD.

Autoantibody-mediated bowel and bladder dysfunction in a patient with chronic, nondiabetic neuropathy.

PubMed

Jackson, Michael W; Gordon, Thomas P; McCombe, Pamela A

2008-04-01

Physiological techniques can be used to detect novel autoantibodies causing alteration of autonomic function after passive transfer to mice. Previously, such antibodies have been detected in patients with type I diabetes mellitus, myasthenia gravis, and Sjogren's syndrome. We now describe a patient with an idiopathic nondiabetic neuropathy with prominent autonomic symptoms, including bladder and bowel dysfunction. Physiological assays of whole colon and bladder were used to determine the presence in the patient serum of functional autoantibodies capable of mediating autonomic dysfunction. Immunoglobulin G (IgG) from this patient was able to disrupt bladder and bowel function on passive transfer to mice. This is a new pattern of autoantibody-mediated abnormality. Although the target antigen is unknown, it is likely to be a cell-surface receptor or ion channel. This case highlights the usefulness of passive transfer studies in detecting functional antibodies in patients with autonomic neuropathy.

Hyperhidrosis associated with subthalamic deep brain stimulation in Parkinson's disease: Insights into central autonomic functional anatomy.

PubMed

Ramirez-Zamora, Adolfo; Smith, Heather; Youn, Youngwon; Durphy, Jennifer; Shin, Damian S; Pilitsis, Julie G

2016-07-15

There is limited evidence regarding the precise location and connections of thermoregulatory centers in humans. We present two patients managed with subthalamic nucleus (STN) Deep Brain Stimulation (DBS) for motor fluctuations in PD that developed reproducible hyperhidrosis with high frequency DBS. To describe the clinical features and analyze the location of the electrodes leading to autonomic activation in both patients. We retrospectively assessed the anatomical localization, electrode programming settings and effects of unilateral STN DBS leading to hyperhidrosis. Unilateral stimulation of anterior and medially located contacts within the STN and zona incerta (Zi) caused bilateral, consistent, reproducible, and reversible sweating in our patients. Adequate control of motor symptoms without autonomic side effects was accomplished with alternative programming settings. Stimulation of the medial Zi and medial and anterior STN causes hyperhidrosis in a pattern similar to that described in primates and rats. We speculate that central autonomic fibers originating in the lateral hypothalamic area project laterally to the ventral/medial Zi and then to brainstem nuclei following an medial and posterior trajectory in relationship to STN. Copyright © 2016 Elsevier B.V. All rights reserved.

Plastics and cardiovascular health: phthalates may disrupt heart rate variability and cardiovascular reactivity.

PubMed

Jaimes, Rafael; Swiercz, Adam; Sherman, Meredith; Muselimyan, Narine; Marvar, Paul J; Posnack, Nikki Gillum

2017-11-01

Plastics have revolutionized medical device technology, transformed hematological care, and facilitated modern cardiology procedures. Despite these advances, studies have shown that phthalate chemicals migrate out of plastic products and that these chemicals are bioactive. Recent epidemiological and research studies have suggested that phthalate exposure adversely affects cardiovascular function. Our objective was to assess the safety and biocompatibility of phthalate chemicals and resolve the impact on cardiovascular and autonomic physiology. Adult mice were implanted with radiofrequency transmitters to monitor heart rate variability, blood pressure, and autonomic regulation in response to di-2-ethylhexyl-phthalate (DEHP) exposure. DEHP-treated animals displayed a decrease in heart rate variability (-17% SD of normal beat-to-beat intervals and -36% high-frequency power) and an exaggerated mean arterial pressure response to ganglionic blockade (31.5% via chlorisondamine). In response to a conditioned stressor, DEHP-treated animals displayed enhanced cardiovascular reactivity (-56% SD major axis Poincarè plot) and prolonged blood pressure recovery. Alterations in cardiac gene expression of endothelin-1, angiotensin-converting enzyme, and nitric oxide synthase may partly explain these cardiovascular alterations. This is the first study to show an association between phthalate chemicals that are used in medical devices with alterations in autonomic regulation, heart rate variability, and cardiovascular reactivity. Because changes in autonomic balance often precede clinical manifestations of hypertension, atherosclerosis, and conduction abnormalities, future studies are warranted to assess the downstream impact of plastic chemical exposure on end-organ function in sensitive patient populations. This study also highlights the importance of adopting safer biomaterials, chemicals, and/or surface coatings for use in medical devices. NEW & NOTEWORTHY Phthalates are widely used in the manufacturing of consumer and medical products. In the present study, di-2-ethylhexyl-phthalate exposure was associated with alterations in heart rate variability and cardiovascular reactivity. This highlights the importance of investigating the impact of phthalates on health and identifying suitable alternatives for medical device manufacturing. Copyright © 2017 the American Physiological Society.

Range Safety for an Autonomous Flight Safety System

NASA Technical Reports Server (NTRS)

Lanzi, Raymond J.; Simpson, James C.

2010-01-01

The Range Safety Algorithm software encapsulates the various constructs and algorithms required to accomplish Time Space Position Information (TSPI) data management from multiple tracking sources, autonomous mission mode detection and management, and flight-termination mission rule evaluation. The software evaluates various user-configurable rule sets that govern the qualification of TSPI data sources, provides a prelaunch autonomous hold-launch function, performs the flight-monitoring-and-termination functions, and performs end-of-mission safing

Interoceptive inference: From computational neuroscience to clinic.

PubMed

Owens, Andrew P; Allen, Micah; Ondobaka, Sasha; Friston, Karl J

2018-04-22

The central and autonomic nervous systems can be defined by their anatomical, functional and neurochemical characteristics, but neither functions in isolation. For example, fundamental components of autonomically mediated homeostatic processes are afferent interoceptive signals reporting the internal state of the body and efferent signals acting on interoceptive feedback assimilated by the brain. Recent predictive coding (interoceptive inference) models formulate interoception in terms of embodied predictive processes that support emotion and selfhood. We propose interoception may serve as a way to investigate holistic nervous system function and dysfunction in disorders of brain, body and behaviour. We appeal to predictive coding and (active) interoceptive inference, to describe the homeostatic functions of the central and autonomic nervous systems. We do so by (i) reviewing the active inference formulation of interoceptive and autonomic function, (ii) survey clinical applications of this formulation and (iii) describe how it offers an integrative approach to human physiology; particularly, interactions between the central and peripheral nervous systems in health and disease. Crown Copyright © 2018. Published by Elsevier Ltd. All rights reserved.

An introduction to autonomous control systems

NASA Technical Reports Server (NTRS)

Antsaklis, Panos J.; Passino, Kevin M.; Wang, S. J.

1991-01-01

The functions, characteristics, and benefits of autonomous control are outlined. An autonomous control functional architecture for future space vehicles that incorporates the concepts and characteristics described is presented. The controller is hierarchical, with an execution level (the lowest level), coordination level (middle level), and management and organization level (highest level). The general characteristics of the overall architecture, including those of the three levels, are explained, and an example to illustrate their functions is given. Mathematical models for autonomous systems, including 'logical' discrete event system models, are discussed. An approach to the quantitative, systematic modeling, analysis, and design of autonomous controllers is also discussed. It is a hybrid approach since it uses conventional analysis techniques based on difference and differential equations and new techniques for the analysis of the systems described with a symbolic formalism such as finite automata. Some recent results from the areas of planning and expert systems, machine learning, artificial neural networks, and the area restructurable controls are briefly outlined.

A Flight Deck Decision Support Tool for Autonomous Airborne Operations

NASA Technical Reports Server (NTRS)

Ballin, Mark G.; Sharma, Vivek; Vivona, Robert A.; Johnson, Edward J.; Ramiscal, Ermin

2002-01-01

NASA is developing a flight deck decision support tool to support research into autonomous operations in a future distributed air/ground traffic management environment. This interactive real-time decision aid, referred to as the Autonomous Operations Planner (AOP), will enable the flight crew to plan autonomously in the presence of dense traffic and complex flight management constraints. In assisting the flight crew, the AOP accounts for traffic flow management and airspace constraints, schedule requirements, weather hazards, aircraft operational limits, and crew or airline flight-planning goals. This paper describes the AOP and presents an overview of functional and implementation design considerations required for its development. Required AOP functionality is described, its application in autonomous operations research is discussed, and a prototype software architecture for the AOP is presented.

12-month efficacy of a single radiofrequency ablation on autonomously functioning thyroid nodules.

PubMed

Bernardi, Stella; Stacul, Fulvio; Michelli, Andrea; Giudici, Fabiola; Zuolo, Giulia; de Manzini, Nicolò; Dobrinja, Chiara; Zanconati, Fabrizio; Fabris, Bruno

2017-09-01

Radiofrequency ablation has been advocated as an alternative to radioiodine and/or surgery for the treatment of autonomously functioning benign thyroid nodules. However, only a few studies have measured radiofrequency ablation efficacy on autonomously functioning benign thyroid nodules. The aim of this work was to evaluate the 12-month efficacy of a single session of radiofrequency ablation (performed with the moving shot technique) on solitary autonomously functioning benign thyroid nodules. Thirty patients with a single, benign autonomously functioning benign thyroid nodules, who were either unwilling or ineligible to undergo surgery and radioiodine, were treated with radiofrequency ablation between April 2012 and May 2015. All the patients underwent a single radiofrequency ablation, performed with the 18-gauge needle and the moving shot technique. Clinical, laboratory, and ultrasound evaluations were scheduled at baseline, and after 1, 3, 6, and 12 months from the procedure. A single radiofrequency ablation reduced thyroid nodule volume by 51, 63, 69, and 75 % after 1, 3, 6, and 12 months, respectively. This was associated with a significant improvement of local cervical discomfort and cosmetic score. As for thyroid function, 33 % of the patients went into remission after 3 months, 43 % after 6 months, and 50 % after 12 months from the procedure. This study demonstrates that a single radiofrequency ablation allowed us to withdraw anti-thyroid medication in 50 % of the patients, who remained euthyroid afterwards. This study shows that a single radiofrequency ablation was effective in 50 % of patients with autonomously functioning benign thyroid nodules. Patients responded gradually to the treatment. It is possible that longer follow-up studies might show greater response rates.

Effect of thyroxine therapy on autonomic status in hypothyroid patients.

PubMed

Lakshmi, Vijaya; Vaney, N; Madhu, S V

2009-01-01

The aim of the present study was to evaluate the impact of hypothyroidism on the autonomic regulation of the cardiovascular system by analyzing sympathetic and parasympathetic influences on the heart and the effect of thyroxine replacement. Thirty newly diagnosed female hypothyroid patients with mean age 32.73 +/- 9.98 years were recruited from the Thyroid Clinic, GTB Hospital, Delhi. Various Autonomic function tests to assess Basal heart rate variability, parasympathetic activity (E:I Ratio, 30:15 Ratio, Valsalva Ratio) and sympathetic activity (Postural Challenge test, Sustained handgrip test) were done before and after attainment of euthyroidism. There was significant increase in parasympathetic activity on achieving euthyroid state. The sympathetic activity too significantly improved after L-thyroxine supplementation. Lipid profile parameters significantly decreased after achieving euthyroid state. Our findings are consistent with previous reports that thyroxine therapy appears to restore the efferent vagal activity and alters the relative contribution of systems that maintain resting blood pressure and heart rate.

Verbal, facial and autonomic responses to empathy-eliciting film clips by disruptive male adolescents with high versus low callous-unemotional traits.

PubMed

de Wied, Minet; van Boxtel, Anton; Matthys, Walter; Meeus, Wim

2012-02-01

This study examined empathy-related responding in male adolescents with disruptive behavior disorder (DBD), high or low on callous-unemotional (CU) traits. Facial electromyographic (EMG) and heart rate (HR) responses were monitored during exposure to empathy-inducing film clips portraying sadness, anger or happiness. Self-reports were assessed afterward. In agreement with expectations, DBD adolescents with high CU traits showed significantly lower levels of empathic sadness than healthy controls across all response systems. Between DBD subgroups significant differences emerged at the level of autonomic (not verbal or facial) reactions to sadness, with high CU respondents showing less HR change from baseline than low CU respondents. The study also examined basal patterns of autonomic function. Resting HR was not different between groups, but resting respiratory sinus arrhythmia (RSA) was significantly lower in DBD adolescents with high CU traits compared to controls. Results support the notion that CU traits designate a distinct subgroup of DBD individuals.

Altered cardiorespiratory coupling in young male adults with excessive online gaming.

PubMed

Chang, Jae Seung; Kim, Eun Young; Jung, Dooyoung; Jeong, Seong Hoon; Kim, Yeni; Roh, Myoung-Sun; Ahn, Yong Min; Hahm, Bong-Jin

2015-09-01

This study aimed to investigate changes in heart rate variability and cardiorespiratory coupling in male college students with problematic Internet use (PIU) excessive gaming type during action video game play to assess the relationship between PIU tendency and central autonomic regulation. Electrocardiograms and respiration were simultaneously recorded from 22 male participants with excessive online gaming and 22 controls during action video game play. Sample entropy (SampEn) was computed to assess autonomic regularity, and cross-SampEn was calculated to quantify autonomic coordination. During video game play, reduced cardiorespiratory coupling (CRC) was observed in individuals with PIU excessive gaming type compared with controls, implicating central autonomic dysregulation. The PIU tendency was associated with the severity of autonomic dysregulation. These findings indicate impaired CRC in PIU excessive gaming type, which may reflect alterations of central inhibitory control over autonomic responses to pleasurable online stimuli. Copyright © 2015 Elsevier B.V. All rights reserved.

Designing Assessment for Autonomous Learning

ERIC Educational Resources Information Center

Hay, Marie; Mathers, Lucy

2012-01-01

This paper aims to disseminate and evaluate an autonomous learning framework developed through collaborative research with first- and second-year undergraduate students at De Montfort University. Central to the framework is the involvement of students in the assessment of their peers and themselves using dialogue about the assessment and feedback…

Sex Differences in Autonomic Correlates of Conduct Problems and Aggression

PubMed Central

BEAUCHAINE, THEODORE P.; HONG, JAMES; MARSH, PENNY

2009-01-01

Objective To examine sex differences in autonomic nervous system functioning in children and adolescents with conduct problems and to evaluate the role of aggression in predicting autonomic nervous system functioning, over and above the effects of disruptive behavior. Although deficiencies in autonomic responding among boys with oppositional defiant disorder and/or conduct disorder are well documented, it remains unclear whether such findings extend to girls or apply only to children with aggressive forms of conduct problems. Method Electrodermal responding, cardiac pre-ejection period, and respiratory sinus arrhythmia were recorded while boys (n = 110; 53 with conduct problems, 57 controls) and girls (n = 65; 33 with conduct problems, 32 controls) between the ages of 8 and 12 sat for an extended baseline, then played a game with conditions of reward and frustrative nonreward. Results Both sex effects and aggression effects were found. Aggressive boys with conduct problems demonstrated reduced autonomic functioning, consistent with previous research. In contrast, aggressive girls with conduct problems exhibited greater electrodermal responding than controls, with no differences in cardiovascular reactivity to incentives. Conclusions Observed sex differences in the autonomic correlates of conduct problems and aggression may suggest different etiological mechanisms of externalizing psychopathology for girls compared with boys. PMID:18520959

Remote detection of human toxicants in real time using a human-optimized, bioluminescent bacterial luciferase gene cassette bioreporter

NASA Astrophysics Data System (ADS)

Close, Dan; Webb, James; Ripp, Steven; Patterson, Stacey; Sayler, Gary

2012-06-01

Traditionally, human toxicant bioavailability screening has been forced to proceed in either a high throughput fashion using prokaryotic or lower eukaryotic targets with minimal applicability to humans, or in a more expensive, lower throughput manner that uses fluorescent or bioluminescent human cells to directly provide human bioavailability data. While these efforts are often sufficient for basic scientific research, they prevent the rapid and remote identification of potentially toxic chemicals required for modern biosecurity applications. To merge the advantages of high throughput, low cost screening regimens with the direct bioavailability assessment of human cell line use, we re-engineered the bioluminescent bacterial luciferase gene cassette to function autonomously (without exogenous stimulation) within human cells. Optimized cassette expression provides for fully endogenous bioluminescent production, allowing continuous, real time monitoring of the bioavailability and toxicology of various compounds in an automated fashion. To access the functionality of this system, two sets of bioluminescent human cells were developed. The first was programed to suspend bioluminescent production upon toxicological challenge to mimic the non-specific detection of a toxicant. The second induced bioluminescence upon detection of a specific compound to demonstrate autonomous remote target identification. These cells were capable of responding to μM concentrations of the toxicant n-decanal, and allowed for continuous monitoring of cellular health throughout the treatment process. Induced bioluminescence was generated through treatment with doxycycline and was detectable upon dosage at a 100 ng/ml concentration. These results demonstrate that leveraging autonomous bioluminescence allows for low-cost, high throughput direct assessment of toxicant bioavailability.

Electrophysiology of Cranial Nerve Testing: Cranial Nerves IX and X.

PubMed

Martinez, Alberto R M; Martins, Melina P; Moreira, Ana Lucila; Martins, Carlos R; Kimaid, Paulo A T; França, Marcondes C

2018-01-01

The cranial nerves IX and X emerge from medulla oblongata and have motor, sensory, and parasympathetic functions. Some of these are amenable to neurophysiological assessment. It is often hard to separate the individual contribution of each nerve; in fact, some of the techniques are indeed a composite functional measure of both nerves. The main methods are the evaluation of the swallowing function (combined IX and X), laryngeal electromyogram (predominant motor vagal function), and heart rate variability (predominant parasympathetic vagal function). This review describes, therefore, the techniques that best evaluate the major symptoms presented in IX and X cranial nerve disturbance: dysphagia, dysphonia, and autonomic parasympathetic dysfunction.

Autonomous control systems - Architecture and fundamental issues

NASA Technical Reports Server (NTRS)

Antsaklis, P. J.; Passino, K. M.; Wang, S. J.

1988-01-01

A hierarchical functional autonomous controller architecture is introduced. In particular, the architecture for the control of future space vehicles is described in detail; it is designed to ensure the autonomous operation of the control system and it allows interaction with the pilot and crew/ground station, and the systems on board the autonomous vehicle. The fundamental issues in autonomous control system modeling and analysis are discussed. It is proposed to utilize a hybrid approach to modeling and analysis of autonomous systems. This will incorporate conventional control methods based on differential equations and techniques for the analysis of systems described with a symbolic formalism. In this way, the theory of conventional control can be fully utilized. It is stressed that autonomy is the design requirement and intelligent control methods appear at present, to offer some of the necessary tools to achieve autonomy. A conventional approach may evolve and replace some or all of the `intelligent' functions. It is shown that in addition to conventional controllers, the autonomous control system incorporates planning, learning, and FDI (fault detection and identification).

Apprentissage auto-dirige: Quand les chiffres parlent (Self-Directed Learning: Figures Speak for Themselves).

ERIC Educational Resources Information Center

Abe, Daniele; Gremmo, Marie-Jose

The functioning of the semi-autonomous learning system (SAAS) at the Centre de Recherches et d'Applications Pedagogiques en Langues (CRAPEL) was surveyed for the academic year 1980-81. Detailed data were collected about learners' aims, language level, and their assessment of the SAAS, as well as about the way they actually used the system. This…

Mechanisms of Cardiopulmonary Adaptation to Microgravity. Part 2

NASA Technical Reports Server (NTRS)

1997-01-01

Session TP1 contains short reports concerning: (1) Autonomic Regulation of Circulation and Mechanical Function of Heart at Different Stages of 14th Month Space Flight; (2) Cardiovascular Oxygen Transport in Exercising Humans in Microgravity; (3) Venous Hemodynamic Changes Assessed by Air Plethysmography During a 16-Day Space Flight; (4) Respiratory Mechanics After 180 Days Space Mission (EUROMIR'95); (5) Assessment of the Sympathetic and the Parasympathetic Nervous Activity During Parabolic Flight by Pupillary Light Reflex; and(6) Vascular Response to Different Gravity.

Cardiorespiratory Fitness and Cardiac Autonomic Function in Diabetes.

PubMed

Röhling, Martin; Strom, Alexander; Bönhof, Gidon J; Roden, Michael; Ziegler, Dan

2017-10-23

This review summarizes the current knowledge on the relationship of physical activity, exercise, and cardiorespiratory fitness (CRF) with cardiovascular autonomic neuropathy (CAN) based on epidemiological, clinical, and interventional studies. The prevalence of CAN increases with age and duration of diabetes. Further risk factors for CAN comprise poor glycemic control, dyslipidemia, abdominal obesity, hypertension, and the presence of diabetic complications. CAN has been also linked to reduced CRF. We recently showed that CRF parameters (e.g., maximal oxidative capacity or oxidative capacity at the anaerobic threshold) are associated with cardiac autonomic function in patients recently diagnosed with type 1 or type 2 diabetes. Exercise interventions have shown that physical activity can increase cardiovagal activity and reduce sympathetic overactivity. In particular, long-term and regularly, but also supervised, performed endurance and high-intense and high-volume exercise improves cardiac autonomic function in patients with type 2 diabetes. By contrast, the evidence in those with type 1 diabetes and also in individuals with prediabetes or metabolic syndrome is weaker. Overall, the studies reviewed herein addressing the question whether favorably modulating the autonomic nervous system may improve CRF during exercise programs support the therapeutic concept to promote physical activity and to achieve physical fitness. However, high-quality exercise interventions, especially in type 1 diabetes and metabolic syndrome including prediabetes, are further required to better understand the relationship between physical activity, fitness, and cardiac autonomic function.

Women's Sexual Health and Reproductive Function After SCI

PubMed Central

Alexander, Marcalee; McLain, Amie B. (Jackson)

2017-01-01

Sexual function and to a lesser extent reproduction are often disrupted in women with spinal cord injuries (SCI), who must be educated to better understand their sexual and reproductive health. Women with SCI are sexually active; they can use psychogenic or reflexogenic stimulation to obtain sexual pleasure and orgasm. Treatment should consider a holistic approach using autonomic standards to describe remaining sexual function and to assess both genital function and psychosocial factors. Assessment of genital function should include thoracolumbar dermatomes, vulvar sensitivity (touch, pressure, vibration), and sacral reflexes. Self-exploration should include not only clitoral stimulation, but also stimulation of the vagina (G spot), cervix, and nipples conveyed by different innervation sources. Treatments may consider PDE5 inhibitors and flibanserin on an individual basis, and secondary consequences of SCI should address concerns with spasticity, pain, incontinence, and side effects of medications. Psychosocial issues must be addressed as possible contributors to sexual dysfunctions (eg, lower self-esteem, past sexual history, depression, dating habits). Pregnancy is possible for women with SCI; younger age at the time of injury and at the time of pregnancy being significant predictors of successful pregnancy, along with marital status, motor score, mobility, and occupational scores. Pregnancy may decrease the level of functioning (eg, self-care, ambulation, upper-extremity tasks), may involve complications (eg, decubitus ulcers, weight gain, urological complications), and must be monitored for postural hypotension and autonomic dysreflexia. Taking into consideration the physical and psychosocial determinants of sexuality and childbearing allows women with SCI to achieve positive sexual and reproductive health. PMID:29339874

Sex differences in autonomic function following maximal exercise.

PubMed

Kappus, Rebecca M; Ranadive, Sushant M; Yan, Huimin; Lane-Cordova, Abbi D; Cook, Marc D; Sun, Peng; Harvey, I Shevon; Wilund, Kenneth R; Woods, Jeffrey A; Fernhall, Bo

2015-01-01

Heart rate variability (HRV), blood pressure variability, (BPV) and heart rate recovery (HRR) are measures that provide insight regarding autonomic function. Maximal exercise can affect autonomic function, and it is unknown if there are sex differences in autonomic recovery following exercise. Therefore, the purpose of this study was to determine sex differences in several measures of autonomic function and the response following maximal exercise. Seventy-one (31 males and 40 females) healthy, nonsmoking, sedentary normotensive subjects between the ages of 18 and 35 underwent measurements of HRV and BPV at rest and following a maximal exercise bout. HRR was measured at minute one and two following maximal exercise. Males have significantly greater HRR following maximal exercise at both minute one and two; however, the significance between sexes was eliminated when controlling for VO2 peak. Males had significantly higher resting BPV-low-frequency (LF) values compared to females and did not significantly change following exercise, whereas females had significantly increased BPV-LF values following acute maximal exercise. Although males and females exhibited a significant decrease in both HRV-LF and HRV-high frequency (HF) with exercise, females had significantly higher HRV-HF values following exercise. Males had a significantly higher HRV-LF/HF ratio at rest; however, both males and females significantly increased their HRV-LF/HF ratio following exercise. Pre-menopausal females exhibit a cardioprotective autonomic profile compared to age-matched males due to lower resting sympathetic activity and faster vagal reactivation following maximal exercise. Acute maximal exercise is a sufficient autonomic stressor to demonstrate sex differences in the critical post-exercise recovery period.

Benign Joint Hypermobility Minimally Impacts Autonomic Abnormalities in Pediatric Subjects with Chronic Functional Pain Disorders.

PubMed

Chelimsky, Gisela; Kovacic, Katja; Simpson, Pippa; Nugent, Melodee; Basel, Donald; Banda, Julie; Chelimsky, Thomas

2016-10-01

To determine if children with benign joint hypermobility (BJH) syndrome and chronic functional pain disorders have more autonomic dysfunction. Retrospective chart review study of pediatric patients seen in the pediatric neurogastroenterology and autonomic clinic who underwent autonomic testing and had either a Beighton score of ≥6 and met Brighton criteria for BJH (with BJH) or a score of ≤2 (no BJH). Twenty-one female subjects (10 without BJH) met inclusion criteria; 64% of BJH had diagnosis confirmed by genetics consultation. We evaluated for postural tachycardia syndrome, syncope, orthostatic intolerance, and orthostatic hypotension. None of these diagnoses, as well as baseline heart rate, peak heart rate in first 10 minutes of head up tilt (P = .35 and P = .61, respectively), and sudomotor index (suggestive of autonomic neuropathy) (P = .58), showed differences between the groups. Age of onset of symptoms was also similar (P = .61) (BJH vs without BJH: median [range]:15.6 years [12.9-17.5] vs 15.4 years [11.1-18.2]). There was no difference between groups in complaints of migraine, chronic nausea, chronic fatigue, lightheadedness, dizziness, fainting >3 times/lifetime, delayed onset of sleep, irritable bowel syndrome, dyspepsia, abdominal migraine, functional abdominal pain, constipation, or fibromyalgia. Children with chronic functional pain disorders and BJH have autonomic testing findings and comorbid features compared with a similar cohort of subjects without BJH, suggesting that BJH is not the driver of the autonomic and comorbid disorders. Copyright © 2016. Published by Elsevier Inc.

Cardiorespiratory coupling in health and disease.

PubMed

Garcia, Alfredo J; Koschnitzky, Jenna E; Dashevskiy, Tatiana; Ramirez, Jan-Marino

2013-04-01

Cardiac and respiratory activities are intricately linked both functionally as well as anatomically through highly overlapping brainstem networks controlling these autonomic physiologies that are essential for survival. Cardiorespiratory coupling (CRC) has many potential benefits creating synergies that promote healthy physiology. However, when such coupling deteriorates autonomic dysautonomia may ensue. Unfortunately there is still an incomplete mechanistic understanding of both normal and pathophysiological interactions that respectively give rise to CRC and cardiorespiratory dysautonomia. Moreover, there is also a need for better quantitative methods to assess CRC. This review addresses the current understanding of CRC by discussing: (1) the neurobiological basis of respiratory sinus arrhythmia (RSA); (2) various disease states involving cardiorespiratory dysautonomia; and (3) methodologies measuring heart rate variability and RSA. Copyright © 2013 Elsevier B.V. All rights reserved.

Cardiorespiratory Coupling in Health and Disease

PubMed Central

Garcia, Alfredo J.; Koschnitzky, Jenna E.; Dashevskiy, Tatiana; Ramirez, Jan-Marino

2013-01-01

Cardiac and respiratory activities are intricately linked both functionally as well as anatomically through highly overlapping brainstem networks controlling these autonomic physiologies that are essential for survival. Cardiorespiratory coupling (CRC) has many potential benefits creating synergies that promote healthy physiology. However, when such coupling deteriorates autonomic dysautonomia may ensue. Unfortunately there is still an incomplete mechanistic understanding of both normal and pathophysiological interactions that respectively give rise to CRC and cardiorespiratory dysautonomia. Moreover, there is also a need for better quantitative methods to assess CRC. This review addresses the current understanding of CRC by discussing: (1) the neurobiological basis of respiratory sinus arrhythmia (RSA); (2) various disease states involving cardiorespiratory dysautonomia; and (3) methodologies measuring heart rate variability and RSA. PMID:23497744

N(N)-nicotinic blockade as an acute human model of autonomic failure

NASA Technical Reports Server (NTRS)

Jordan, J.; Shannon, J. R.; Black, B. K.; Lance, R. H.; Squillante, M. D.; Costa, F.; Robertson, D.

1998-01-01

Pure autonomic failure has been conceptualized as deficient sympathetic and parasympathetic innervation. Several recent observations in chronic autonomic failure, however, cannot be explained simply by loss of autonomic innervation, at least according to our current understanding. To simulate acute autonomic failure, we blocked N(N)-nicotinic receptors with intravenous trimethaphan (6+/-0.4 mg/min) in 7 healthy subjects (4 men, 3 women, aged 32+/-3 years, 68+/-4 kg, 171+/-5 cm). N(N)-Nicotinic receptor blockade resulted in near-complete interruption of sympathetic and parasympathetic efferents as indicated by a battery of autonomic function tests. With trimethaphan, small postural changes from the horizontal were associated with significant blood pressure changes without compensatory changes in heart rate. Gastrointestinal motility, pupillary function, saliva production, and tearing were profoundly suppressed with trimethaphan. Plasma norepinephrine level decreased from 1.1+/-0.12 nmol/L (180+/-20 pg/mL) at baseline to 0.23+/-0.05 nmol/L (39+/-8 pg/mL) with trimethaphan (P<.001). There was a more than 16-fold increase in plasma vasopressin (P<.01) and no change in plasma renin activity. We conclude that blockade of N(N)-cholinergic receptors is useful to simulate the hemodynamic alterations of acute autonomic failure in humans. The loss of function with acute N(N)-cholinergic blockade is more complete than in most cases of chronic autonomic failure. This difference may be exploited to elucidate the contributions of acute denervation and chronic adaptation to the pathophysiology of autonomic failure. N(N)-Cholinergic blockade may also be applied to study human cardiovascular physiology and pharmacology in the absence of confounding baroreflexes.

Methods of assessment of the post-exercise cardiac autonomic recovery: A methodological review.

PubMed

Peçanha, Tiago; Bartels, Rhenan; Brito, Leandro C; Paula-Ribeiro, Marcelle; Oliveira, Ricardo S; Goldberger, Jeffrey J

2017-01-15

The analysis of post-exercise cardiac autonomic recovery is a practical clinical tool for the assessment of cardiovascular health. A reduced heart rate recovery - an indicator of autonomic dysfunction - has been found in a broad range of cardiovascular diseases and has been associated with increased risks of both cardiac and all-cause mortality. For this reason, over the last several years, non-invasive methods for the assessment of cardiac autonomic recovery after exercise - either based on heart rate recovery or heart rate variability indices - have been proposed. However, for the proper implementation of such methods in daily clinical practice, the discussion of their clinical validity, physiologic meaning, mathematical formulation and reproducibility should be better addressed. Therefore, the aim of this methodological review is to present some of the most employed methods of post-exercise cardiac autonomic recovery in the literature and comprehensively discuss their strengths and weaknesses. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Cardiovascular autonomic dysfunction in Ehlers-Danlos syndrome-Hypermobile type.

PubMed

Hakim, Alan; O'Callaghan, Chris; De Wandele, Inge; Stiles, Lauren; Pocinki, Alan; Rowe, Peter

2017-03-01

Autonomic dysfunction contributes to health-related impairment of quality of life in the hypermobile type of Ehlers-Danlos syndrome (hEDS). Typical signs and symptoms include tachycardia, hypotension, gastrointestinal dysmotility, and disturbed bladder function and sweating regulation. Cardiovascular autonomic dysfunction may present as Orthostatic Intolerance, Orthostatic Hypotension, Postural Orthostatic Tachycardia Syndrome, or Neurally Mediated Hypotension. The incidence, prevalence, and natural history of these conditions remain unquantified, but observations from specialist clinics suggest they are frequently seen in hEDS. There is growing understanding of how hEDS-related physical and physiological pathology contributes to the development of these conditions. Evaluation of cardiovascular symptoms in hEDS should include a careful history and clinical examination. Tests of cardiovascular function range from clinic room observation to tilt-table assessment to other laboratory investigations such as supine and standing catecholamine levels. Non-pharmacologic treatments include education, managing the environment to reduce exposure to triggers, improving cardiovascular fitness, and maintaining hydration. Although there are limited clinical trials, the response to drug treatments in hEDS is supported by evidence from case and cohort observational data, and short-term physiological studies. Pharmacologic therapy is indicated for patients with moderate-severe impairment of daily function and who have inadequate response or tolerance to conservative treatment. Treatment in hEDS often requires a focus on functional maintenance. Also, the negative impact of cardiovascular symptoms on physical and psycho-social well-being may generate a need for a more general evaluation and on-going management and support. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

Effects of Cholinergic Stimulation with Pyridostigmine Bromide on Chronic Chagasic Cardiomyopathic Mice

PubMed Central

de Cuba, Marília Beatriz; Ribeiro Machado, Marcus Paulo; Farnesi, Thais Soares; Alves, Angelica Cristina; Martins, Livia Alves; de Oliveira, Lucas Felipe; Capitelli, Caroline Santos; Leite, Camila Ferreira; Vinícius Silva, Marcos; Machado, Juliana Reis; Kappel, Henrique Borges; Sales de Campos, Helioswilton; Paiva, Luciano; da Silva Gomes, Natália Lins; Guimarães Faleiros, Ana Carolina; Britto, Constança Felicia de Paoli de Carvalho; Savino, Wilson; Moreira, Otacílio Cruz; Rodrigues Jr., Virmondes; Montano, Nicola; Lages-Silva, Eliane; Ramirez, Luis Eduardo; Dias da Silva, Valdo Jose

2014-01-01

The aim of the present study was to assess the effects of an anticholinesterase agent, pyridostigmine bromide (Pyrido), on experimental chronic Chagas heart disease in mice. To this end, male C57BL/6J mice noninfected (control:Con) or chronically infected (5 months) with Trypanosoma cruzi (chagasic:Chg) were treated or not (NT) with Pyrido for one month. At the end of this period, electrocardiogram (ECG); cardiac autonomic function; heart histopathology; serum cytokines; and the presence of blood and tissue parasites by means of immunohistochemistry and PCR were assessed. In NT-Chg mice, significant changes in the electrocardiographic, autonomic, and cardiac histopathological profiles were observed confirming a chronic inflammatory response. Treatment with Pyrido in Chagasic mice caused a significant reduction of myocardial inflammatory infiltration, fibrosis, and hypertrophy, which was accompanied by a decrease in serum levels of IFNγ with no change in IL-10 levels, suggesting a shift of immune response toward an anti-inflammatory profile. Lower nondifferent numbers of parasite DNA copies were observed in both treated and nontreated chagasic mice. In conclusion, our findings confirm the marked neuroimmunomodulatory role played by the parasympathetic autonomic nervous system in the evolution of the inflammatory-immune response to T. cruzi during experimental chronic Chagas heart disease in mice. PMID:25221388

Effects of cholinergic stimulation with pyridostigmine bromide on chronic chagasic cardiomyopathic mice.

PubMed

de Cuba, Marília Beatriz; Machado, Marcus Paulo Ribeiro; Farnesi, Thais Soares; Alves, Angelica Cristina; Martins, Livia Alves; de Oliveira, Lucas Felipe; Capitelli, Caroline Santos; Leite, Camila Ferreira; Silva, Marcos Vinícius; Machado, Juliana Reis; Kappel, Henrique Borges; de Campos, Helioswilton Sales; Paiva, Luciano; Gomes, Natália Lins da Silva; Faleiros, Ana Carolina Guimarães; Britto, Constança Felicia de Paoli de Carvalho; Savino, Wilson; Moreira, Otacílio Cruz; Rodrigues, Virmondes; Montano, Nicola; Lages-Silva, Eliane; Ramirez, Luis Eduardo; da Silva, Valdo Jose Dias

2014-01-01

The aim of the present study was to assess the effects of an anticholinesterase agent, pyridostigmine bromide (Pyrido), on experimental chronic Chagas heart disease in mice. To this end, male C57BL/6J mice noninfected (control:Con) or chronically infected (5 months) with Trypanosoma cruzi (chagasic:Chg) were treated or not (NT) with Pyrido for one month. At the end of this period, electrocardiogram (ECG); cardiac autonomic function; heart histopathology; serum cytokines; and the presence of blood and tissue parasites by means of immunohistochemistry and PCR were assessed. In NT-Chg mice, significant changes in the electrocardiographic, autonomic, and cardiac histopathological profiles were observed confirming a chronic inflammatory response. Treatment with Pyrido in Chagasic mice caused a significant reduction of myocardial inflammatory infiltration, fibrosis, and hypertrophy, which was accompanied by a decrease in serum levels of IFNγ with no change in IL-10 levels, suggesting a shift of immune response toward an anti-inflammatory profile. Lower nondifferent numbers of parasite DNA copies were observed in both treated and nontreated chagasic mice. In conclusion, our findings confirm the marked neuroimmunomodulatory role played by the parasympathetic autonomic nervous system in the evolution of the inflammatory-immune response to T. cruzi during experimental chronic Chagas heart disease in mice.

An Exploratory Study of Autonomic Function Investigations in Hemophiliacs on Homoeopathy Medications Using Impedance Plethysmography.

PubMed

Kundu, Tapas K; Barde, Pradip B; Jindal, Ghanshyam D; Motiwala, Farooq F

2017-10-01

Status of autonomic homoeostasis in hemostasic disturbances due to hemophilia needs to be studied. To compare autonomic nervous system markers measured by heart rate variability (HRV) and blood flow variability (BFV) in hemophiliacs and healthy age-matched control population using medical analyzer system. Cross-sectional study. Motiwala Homoeopathy Medical College, and Hemophilia Clinics, Nashik. Eighty subjects. Nil. Autonomic function markers for HRV and BFV. Among 80 subjects, BFV time domain measure, root mean square of successive NN (normal-to-normal) interval differences (RMSSD), was significantly higher among hemophiliacs than nonhemophiliacs. Frequency domain analysis parameter, low frequency for both HRV and BFV was significantly higher among hemophiliacs as compared with nonhemophiliacs. Hemophiliacs were shown to have higher autonomic activity as compared with healthy controls. Homoeopathic medicines used as an adjunct was associated with decrease in parasympathetic modulations.

Evaluating the impact of depression, anxiety & autonomic function on health related quality of life, vocational functioning and health care utilisation in acute coronary syndrome patients: the ADVENT study protocol

PubMed Central

2013-01-01

Background Depression and anxiety are highly prevalent and co-morbid in acute coronary syndrome patients. Somatic and cognitive subtypes of depression and anxiety in acute coronary syndrome have been shown to be associated with mortality although their association with patient outcomes is unknown, as are the mechanisms that underpin these associations. We are conducting a prospective cohort study which aims to examine in acute coronary syndrome patients: (1) the role of somatic subtypes of depression and anxiety as predictors of health related quality of life outcomes; (2) how somatic subtypes of depression and anxiety relate to long term vocational functioning and healthcare utilisation; and (3) the role of the autonomic nervous system assessed by heart rate variability as a moderator of these associations. Methods Patients are being screened after index admission for acute coronary syndrome at a single, high volume centre, MonashHeart, Monash Health, Victoria, Australia. The inclusion criterion is all patients aged > 21 years old and fluent in English admitted to MonashHeart, Monash Health with a diagnosis of acute coronary syndrome. The primary outcome is mean health related quality of life (Short Form-36) Physical and Mental Health Summary scores at 12 and 24 months in subtypes with somatic symptoms of depression and anxiety. Depressive domains are assessed by the Beck Depression Inventory II and the Cardiac Depression Scale. Anxiety is measured using the Speilberger State-Trait Anxiety Inventory and the Crown Crisp Phobic Anxiety questionnaire. Secondary outcomes include clinical variables, healthcare service utilisation and vocational functioning. Discussion This manuscript presents the protocol for a prospective cohort study which will investigate the role of somatic subtypes of depression and anxiety as predictors of health related quality of life, long-term vocational functioning and health service use, and the role of the autonomic nervous system in moderating these associations. Findings from the study have the potential to inform more effective pharmacological, psychological and behavioural interventions and better guide health policy on the use of health care resources. PMID:24237848

Exercise training starting at weaning age preserves cardiac pacemaker function in adulthood of diet-induced obese rats.

PubMed

Carvalho de Lima, Daniel; Guimarães, Juliana Bohnen; Rodovalho, Gisele Vieira; Silveira, Simonton Andrade; Haibara, Andrea Siqueira; Coimbra, Cândido Celso

2014-08-01

Peripheral sympathetic overdrive in young obese subjects contributes to further aggravation of insulin resistance, diabetes, and hypertension, thus inducing worsening clinical conditions in adulthood. Exercise training has been considered a strategy to repair obesity autonomic dysfunction, thereby reducing the cardiometabolic risk. Therefore, the aim of this study was to assess the effect of early exercise training, starting immediately after weaning, on cardiac autonomic control in diet-induced obese rats. Male Wistar rats (weaning) were divided into four groups: (i) a control group (n = 6); (ii) an exercise-trained control group (n = 6); (iii) a diet-induced obesity group (n = 6); and (iv) an exercise-trained diet-induced obesity group (n = 6). The development of obesity was induced by 9 weeks of palatable diet intake, and the training program was implemented in a motor-driven treadmill (5 times per week) during the same period. After this period, animals were submitted to vein and artery catheter implantation to assess cardiac autonomic balance by methylatropine (3 mg/kg) and propranolol (4 mg/kg) administration. Exercise training increased running performance in both groups (p < 0.05). Exercise training also prevented the increased resting heart rate in obese rats, which seemed to be related to cardiac pacemaker activity preservation (p < 0.05). Additionally, the training program preserved the pressure and bradycardia responses to autonomic blockade in obese rats (p < 0.05). An exercise program beginning at weaning age prevents cardiovascular dysfunction in obese rats, indicating that exercise training may be used as a nonpharmacological therapeutic strategy for the treatment of cardiometabolic diseases.

Autonomous Soil Assessment System: A Data-Driven Approach to Planetary Mobility Hazard Detection

NASA Astrophysics Data System (ADS)

Raimalwala, K.; Faragalli, M.; Reid, E.

2018-04-01

The Autonomous Soil Assessment System predicts mobility hazards for rovers. Its development and performance are presented, with focus on its data-driven models, machine learning algorithms, and real-time sensor data fusion for predictive analytics.

Stating asymmetry in neural pathways: methodological trends in autonomic neuroscience.

PubMed

Xavier, Carlos Henrique; Mendonça, Michelle Mendanha; Marins, Fernanda Ribeiro; da Silva, Elder Sales; Ianzer, Danielle; Colugnati, Diego Basile; Pedrino, Gustavo Rodrigues; Fontes, Marco Antonio Peliky

2018-05-22

Many particularities concerning interhemispheric differences still need to be explored and unveiled. Functional and anatomical differential features found between left and right brain sides are best known as asymmetries and are consequence of the unilateral neuronal recruitment or predominance that is set to organize some function. The outflow from different neural pathways involved in the autonomic control of the cardiovascular system may route through asymmetrically relayed efferences (ipsilateral/lateralized and/or contralateral). In spite of this, the literature reporting on the role of central nuclei involved in the autonomic control is not always dedicated on these interhemispheric comparisons. Considering the recent reports demonstrating that asymmetries may set differential functional responses, it is worth checking differences between right and left sides of central regions. This review aims to inspire neuroscientists with the idea that studying the interhemispheric differences may deepen the understanding on several centrally controlled responses, with special regard to the autonomic functions underlying the cardiovascular regulation. Thus, an avenue of knowledge may unfold from a field of research that requires further exploration.

Clinical models of cardiovascular regulation after weightlessness

NASA Technical Reports Server (NTRS)

Robertson, D.; Jacob, G.; Ertl, A.; Shannon, J.; Mosqueda-Garcia, R.; Robertson, R. M.; Biaggioni, I.

1996-01-01

After several days in microgravity, return to earth is attended by alterations in cardiovascular function. The mechanisms underlying these effects are inadequately understood. Three clinical disorders of autonomic function represent possible models of this abnormal cardiovascular function after spaceflight. They are pure autonomic failure, baroreflex failure, and orthostatic intolerance. In pure autonomic failure, virtually complete loss of sympathetic and parasympathetic function occurs along with profound and immediate orthostatic hypotension. In baroreflex failure, various degrees of debuffering of blood pressure occur. In acute and complete baroreflex failure, there is usually severe hypertension and tachycardia, while with less complete and more chronic baroreflex impairment, orthostatic abnormalities may be more apparent. In orthostatic intolerance, blood pressure fall is minor, but orthostatic symptoms are prominent and tachycardia frequently occurs. Only careful autonomic studies of human subjects in the microgravity environment will permit us to determine which of these models most closely reflects the pathophysiology brought on by a period of time in the microgravity environment.

Association of glucose homeostasis measures with heart rate variability among Hispanic/Latino adults without diabetes: the Hispanic Community Health Study/Study of Latinos (HCHS/SOL).

PubMed

Meyer, Michelle L; Gotman, Nathan M; Soliman, Elsayed Z; Whitsel, Eric A; Arens, Raanan; Cai, Jianwen; Daviglus, Martha L; Denes, Pablo; González, Hector M; Moreiras, Juan; Talavera, Gregory A; Heiss, Gerardo

2016-03-16

Reduced heart rate variability (HRV), a measure of cardiac autonomic function, is associated with an increased risk of cardiovascular disease (CVD) and mortality. Glucose homeostasis measures are associated with reduced cardiac autonomic function among those with diabetes, but inconsistent associations have been reported among those without diabetes. This study aimed to examine the association of glucose homeostasis measures with cardiac autonomic function among diverse Hispanic/Latino adults without diabetes. The Hispanic community Health Study/Study of Latinos (HCHS/SOL; 2008-2011) used two-stage area probability sampling of households to enroll 16,415 self-identified Hispanics/Latinos aged 18-74 years from four USA communities. Resting, standard 12-lead electrocardiogram recordings were used to estimate the following ultrashort-term measures of HRV: RR interval (RR), standard deviation of all normal to normal RR (SDNN) and root mean square of successive differences in RR intervals (RMSSD). Multivariable regression analysis was used to estimate associations between glucose homeostasis measures with HRV using data from 11,994 adults without diabetes (mean age 39 years; 52 % women). Higher fasting glucose was associated with lower RR, SDNN, and RMSSD. Fasting insulin and the homeostasis model assessment of insulin resistance was negatively associated with RR, SDNN, and RMSSD, and the association was stronger among men compared with women. RMSSD was, on average, 26 % lower in men with higher fasting insulin and 29 % lower in men with lower insulin resistance; for women, the corresponding estimates were smaller at 4 and 9 %, respectively. Higher glycated hemoglobin was associated with lower RR, SDNN, and RMSSD in those with abdominal adiposity, defined by sex-specific cut-points for waist circumference, after adjusting for demographics and medication use. There were no associations between glycated hemoglobin and HRV measures among those without abdominal adiposity. Impairment in glucose homeostasis was associated with lower HRV in Hispanic/Latino adults without diabetes, most prominently in men and individuals with abdominal adiposity. These results suggest that reduced cardiac autonomic function is associated with metabolic impairments before onset of overt diabetes in certain subgroups, offering clues for the pathophysiologic processes involved as well as opportunity for identification of those at high risk before autonomic control is manifestly impaired.

Vagus nerve stimulation: state of the art of stimulation and recording strategies to address autonomic function neuromodulation

NASA Astrophysics Data System (ADS)

Guiraud, David; Andreu, David; Bonnet, Stéphane; Carrault, Guy; Couderc, Pascal; Hagège, Albert; Henry, Christine; Hernandez, Alfredo; Karam, Nicole; Le Rolle, Virginie; Mabo, Philippe; Maciejasz, Paweł; Malbert, Charles-Henri; Marijon, Eloi; Maubert, Sandrine; Picq, Chloé; Rossel, Olivier; Bonnet, Jean-Luc

2016-08-01

Objective. Neural signals along the vagus nerve (VN) drive many somatic and autonomic functions. The clinical interest of VN stimulation (VNS) is thus potentially huge and has already been demonstrated in epilepsy. However, side effects are often elicited, in addition to the targeted neuromodulation. Approach. This review examines the state of the art of VNS applied to two emerging modulations of autonomic function: heart failure and obesity, especially morbid obesity. Main results. We report that VNS may benefit from improved stimulation delivery using very advanced technologies. However, most of the results from fundamental animal studies still need to be demonstrated in humans.

Immobile Robots: AI in the New Millennium

NASA Technical Reports Server (NTRS)

Williams, Brian C.; Nayak, P. Pandurang

1996-01-01

A new generation of sensor rich, massively distributed, autonomous systems are being developed that have the potential for profound social, environmental, and economic change. These include networked building energy systems, autonomous space probes, chemical plant control systems, satellite constellations for remote ecosystem monitoring, power grids, biosphere-like life support systems, and reconfigurable traffic systems, to highlight but a few. To achieve high performance, these immobile robots (or immobots) will need to develop sophisticated regulatory and immune systems that accurately and robustly control their complex internal functions. To accomplish this, immobots will exploit a vast nervous system of sensors to model themselves and their environment on a grand scale. They will use these models to dramatically reconfigure themselves in order to survive decades of autonomous operations. Achieving these large scale modeling and configuration tasks will require a tight coupling between the higher level coordination function provided by symbolic reasoning, and the lower level autonomic processes of adaptive estimation and control. To be economically viable they will need to be programmable purely through high level compositional models. Self modeling and self configuration, coordinating autonomic functions through symbolic reasoning, and compositional, model-based programming are the three key elements of a model-based autonomous systems architecture that is taking us into the New Millennium.

Pilot In Command: A Feasibility Assessment of Autonomous Flight Management Operations

NASA Technical Reports Server (NTRS)

Wing, David J.; Ballin, Mark G.; Krishnamurthy, Karthik

2004-01-01

Several years of NASA research have produced the air traffic management operational concept of Autonomous Flight Management with high potential for operational feasibility, significant system and user benefits, and safety. Among the chief potential benefits are demand-adaptive or scalable capacity, user flexibility and autonomy that may finally enable truly successful business strategies, and compatibility with current-day operations such that the implementation rate can be driven from within the user community. A concept summary of Autonomous Flight Management is provided, including a description of how these operations would integrate in shared airspace with existing ground-controlled flight operations. The mechanisms enabling the primary benefits are discussed, and key findings of a feasibility assessment of airborne autonomous operations are summarized. Concept characteristics that impact safety are presented, and the potential for initially implementing Autonomous Flight Management is discussed.

Autonomous Control of Space Reactor Systems

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

Belle R. Upadhyaya; K. Zhao; S.R.P. Perillo

2007-11-30

Autonomous and semi-autonomous control is a key element of space reactor design in order to meet the mission requirements of safety, reliability, survivability, and life expectancy. Interrestrial nuclear power plants, human operators are avilable to perform intelligent control functions that are necessary for both normal and abnormal operational conditions.

Planning Flight Paths of Autonomous Aerobots

NASA Technical Reports Server (NTRS)

Kulczycki, Eric; Elfes, Alberto; Sharma, Shivanjli

2009-01-01

Algorithms for planning flight paths of autonomous aerobots (robotic blimps) to be deployed in scientific exploration of remote planets are undergoing development. These algorithms are also adaptable to terrestrial applications involving robotic submarines as well as aerobots and other autonomous aircraft used to acquire scientific data or to perform surveying or monitoring functions.

Bilevel Shared Control Of A Remote Robotic Manipulator

NASA Technical Reports Server (NTRS)

Hayati, Samad A.; Venkataraman, Subramanian T.

1992-01-01

Proposed concept blends autonomous and teleoperator control modes, each overcoming deficiencies of the other. Both task-level and execution-level functions performed at local and remote sites. Applicable to systems with long communication delay between local and remote sites or systems intended to function partly autonomously.

A Collaborative Knowledge Plane for Autonomic Networks

NASA Astrophysics Data System (ADS)

Mbaye, Maïssa; Krief, Francine

Autonomic networking aims to give network components self-managing capabilities. Several autonomic architectures have been proposed. Each of these architectures includes sort of a knowledge plane which is very important to mimic an autonomic behavior. Knowledge plane has a central role for self-functions by providing suitable knowledge to equipment and needs to learn new strategies for more accuracy.However, defining knowledge plane's architecture is still a challenge for researchers. Specially, defining the way cognitive supports interact each other in knowledge plane and implementing them. Decision making process depends on these interactions between reasoning and learning parts of knowledge plane. In this paper we propose a knowledge plane's architecture based on machine learning (inductive logic programming) paradigm and situated view to deal with distributed environment. This architecture is focused on two self-functions that include all other self-functions: self-adaptation and self-organization. Study cases are given and implemented.

Materials learning from life: concepts for active, adaptive and autonomous molecular systems.

PubMed

Merindol, Rémi; Walther, Andreas

2017-09-18

Bioinspired out-of-equilibrium systems will set the scene for the next generation of molecular materials with active, adaptive, autonomous, emergent and intelligent behavior. Indeed life provides the best demonstrations of complex and functional out-of-equilibrium systems: cells keep track of time, communicate, move, adapt, evolve and replicate continuously. Stirred by the understanding of biological principles, artificial out-of-equilibrium systems are emerging in many fields of soft matter science. Here we put in perspective the molecular mechanisms driving biological functions with the ones driving synthetic molecular systems. Focusing on principles that enable new levels of functionalities (temporal control, autonomous structures, motion and work generation, information processing) rather than on specific material classes, we outline key cross-disciplinary concepts that emerge in this challenging field. Ultimately, the goal is to inspire and support new generations of autonomous and adaptive molecular devices fueled by self-regulating chemistry.

Examining the Roles of Work Autonomous and Controlled Motivations on Satisfaction and Anxiety as a Function of Role Ambiguity.

PubMed

Gillet, Nicolas; Fouquereau, Evelyne; Lafrenière, Marc-André K; Huyghebaert, Tiphaine

2016-07-03

Past research in the self-determination theory has shown that autonomous motivation is associated with positive outcomes (e.g., work satisfaction), whereas controlled motivation is related to negative outcomes (e.g., anxiety). The purpose of the present research was to examine the moderating function of role ambiguity on the relationships between work autonomous and controlled motivations on the one hand, and work satisfaction and anxiety on the other. Six hundred and ninety-eight workers (449 men and 249 women) participated in this study. Results revealed that autonomous motivation was most strongly related to satisfaction when ambiguity was low. In addition, controlled motivation was most strongly related to anxiety when ambiguity was high. In other words, the present findings suggest that the outcomes associated with each form of motivation may vary as a function of role ambiguity. The present study thus offers meaningful insights for organizations, managers, and employees.

Neural correlates of the behavioral-autonomic interaction response to potentially threatening stimuli

PubMed Central

Farrow, Tom F. D.; Johnson, Naomi K.; Hunter, Michael D.; Barker, Anthony T.; Wilkinson, Iain D.; Woodruff, Peter W. R.

2013-01-01

Subjective assessment of emotional valence is typically associated with both brain activity and autonomic arousal. Accurately assessing emotional salience is particularly important when perceiving threat. We sought to characterize the neural correlates of the interaction between behavioral and autonomic responses to potentially threatening visual and auditory stimuli. Twenty-five healthy male subjects underwent fMRI scanning whilst skin conductance responses (SCR) were recorded. One hundred and eighty pictures, sentences, and sounds were assessed as “harmless” or “threatening.” Individuals' stimulus-locked, phasic SCRs and trial-by-trial behavioral assessments were entered as regressors into a flexible factorial design to establish their separate autonomic and behavioral neural correlates, and convolved to examine psycho-autonomic interaction (PAI) effects. Across all stimuli, “threatening,” compared with “harmless” behavioral assessments were associated with mainly frontal and precuneus activation with specific within-modality activations including bilateral parahippocampal gyri (pictures), bilateral anterior cingulate cortex (ACC) and frontal pole (sentences), and right Heschl's gyrus and bilateral temporal gyri (sounds). Across stimulus modalities SCRs were associated with activation of parieto-occipito-thalamic regions, an activation pattern which was largely replicated within-modality. In contrast, PAI analyses revealed modality-specific activations including right fusiform/parahippocampal gyrus (pictures), right insula (sentences), and mid-cingulate gyrus (sounds). Phasic SCR activity was positively correlated with an individual's propensity to assess stimuli as “threatening.” SCRs may modulate cognitive assessments on a “harmless–threatening” dimension, thereby modulating affective tone and hence behavior. PMID:23335893

An Exploratory Study of Autonomic Function Investigations in Hemophiliacs on Homoeopathy Medications Using Impedance Plethysmography

PubMed Central

Kundu, Tapas K.; Barde, Pradip B.; Jindal, Ghanshyam D.; Motiwala, Farooq F.

2017-01-01

Background. Status of autonomic homoeostasis in hemostasic disturbances due to hemophilia needs to be studied. Objectives. To compare autonomic nervous system markers measured by heart rate variability (HRV) and blood flow variability (BFV) in hemophiliacs and healthy age-matched control population using medical analyzer system. Design. Cross-sectional study. Settings. Motiwala Homoeopathy Medical College, and Hemophilia Clinics, Nashik. Subjects. Eighty subjects. Interventions. Nil. Outcome Measures. Autonomic function markers for HRV and BFV. Results. Among 80 subjects, BFV time domain measure, root mean square of successive NN (normal-to-normal) interval differences (RMSSD), was significantly higher among hemophiliacs than nonhemophiliacs. Frequency domain analysis parameter, low frequency for both HRV and BFV was significantly higher among hemophiliacs as compared with nonhemophiliacs. Conclusions. Hemophiliacs were shown to have higher autonomic activity as compared with healthy controls. Homoeopathic medicines used as an adjunct was associated with decrease in parasympathetic modulations. PMID:28719973

An Autonomous Control System for an Intra-Vehicular Spacecraft Mobile Monitor Prototype

NASA Technical Reports Server (NTRS)

Dorais, Gregory A.; Desiano, Salvatore D.; Gawdiak, Yuri; Nicewarner, Keith

2003-01-01

This paper presents an overview of an ongoing research and development effort at the NASA Ames Research Center to create an autonomous control system for an internal spacecraft autonomous mobile monitor. It primary functions are to provide crew support and perform intra- vehicular sensing activities by autonomously navigating onboard the International Space Station. We describe the mission roles and high-level functional requirements for an autonomous mobile monitor. The mobile monitor prototypes, of which two are operational and one is actively being designed, physical test facilities used to perform ground testing, including a 3D micro-gravity test facility, and simulators are briefly described. We provide an overview of the autonomy framework and describe each of its components, including those used for automated planning, goal-oriented task execution, diagnosis, and fault recovery. A sample mission test scenario is also described.

Design of a biochemical circuit motif for learning linear functions

PubMed Central

Lakin, Matthew R.; Minnich, Amanda; Lane, Terran; Stefanovic, Darko

2014-01-01

Learning and adaptive behaviour are fundamental biological processes. A key goal in the field of bioengineering is to develop biochemical circuit architectures with the ability to adapt to dynamic chemical environments. Here, we present a novel design for a biomolecular circuit capable of supervised learning of linear functions, using a model based on chemical reactions catalysed by DNAzymes. To achieve this, we propose a novel mechanism of maintaining and modifying internal state in biochemical systems, thereby advancing the state of the art in biomolecular circuit architecture. We use simulations to demonstrate that the circuit is capable of learning behaviour and assess its asymptotic learning performance, scalability and robustness to noise. Such circuits show great potential for building autonomous in vivo nanomedical devices. While such a biochemical system can tell us a great deal about the fundamentals of learning in living systems and may have broad applications in biomedicine (e.g. autonomous and adaptive drugs), it also offers some intriguing challenges and surprising behaviours from a machine learning perspective. PMID:25401175

Design of a biochemical circuit motif for learning linear functions.

PubMed

Lakin, Matthew R; Minnich, Amanda; Lane, Terran; Stefanovic, Darko

2014-12-06

Learning and adaptive behaviour are fundamental biological processes. A key goal in the field of bioengineering is to develop biochemical circuit architectures with the ability to adapt to dynamic chemical environments. Here, we present a novel design for a biomolecular circuit capable of supervised learning of linear functions, using a model based on chemical reactions catalysed by DNAzymes. To achieve this, we propose a novel mechanism of maintaining and modifying internal state in biochemical systems, thereby advancing the state of the art in biomolecular circuit architecture. We use simulations to demonstrate that the circuit is capable of learning behaviour and assess its asymptotic learning performance, scalability and robustness to noise. Such circuits show great potential for building autonomous in vivo nanomedical devices. While such a biochemical system can tell us a great deal about the fundamentals of learning in living systems and may have broad applications in biomedicine (e.g. autonomous and adaptive drugs), it also offers some intriguing challenges and surprising behaviours from a machine learning perspective.

Variation in the functioning of autonomous self-pollination, pollinator services and floral traits in three Centaurium species

PubMed Central

Brys, Rein; Jacquemyn, Hans

2011-01-01

Background and Aims Reproductive assurance through autonomous selfing is thought to be one of the main advantages of self-fertilization in plants. Floral mechanisms that ensure autonomous seed set are therefore more likely to occur in species that grow in habitats where pollination is scarce and/or unpredictable. Methods Emasculation and pollen supplementation experiments were conducted under laboratory conditions to investigate the capacity for, and timing of autonomous selfing in three closely related Centaurium species (Centaurium erythraea, C. littorale and C. pulchellum). In addition, observations of flower visitors were combined with emasculation and pollen addition experiments in natural populations to investigate the degree of pollinator limitation and pollination failure and to assess the extent to which autonomous selfing conferred reproductive assurance. Results All three species were capable of autonomous selfing, although this capacity differed significantly between species (index of autonomous selfing 0·55 ± 0·06, 0·68 ± 0·09 and 0·92 ± 0·03 for C. erythraea, C. littorale and C. pulchellum, respectively). The efficiency and timing of autogamous selfing was primarily associated with differences in the degree of herkogamy and dichogamy. The number of floral visitors showed significant interspecific differences, with 1·6 ± 0·6, 5·4 ± 0·6 and 14·5 ± 2·1 floral visitors within a 2 × 2 m2 plot per 20-min observation period, for C. pulchellum, C. littorale and C. erythraea, respectively. Concomitantly, pollinator failure was highest in C. pulchellum and lowest in C. erythraea. Nonetheless, all three study species showed very low levels of pollen limitation (index of pollen limitation 0·14 ± 0·03, 0·11 ± 0·03 and 0·09 ± 0·02 for C. erythraea, C. littorale and C. pulchellum, respectively), indicating that autonomous selfing may guarantee reproductive assurance. Conclusions These findings show that limited availability of pollinators may select for floral traits and plant mating strategies that lead to a system of reproductive assurance via autonomous selfing. PMID:21320880

Effect of HeartMate left ventricular assist device on cardiac autonomic nervous activity.

PubMed

Kim, S Y; Montoya, A; Zbilut, J P; Mawulawde, K; Sullivan, H J; Lonchyna, V A; Terrell, M R; Pifarré, R

1996-02-01

Clinical performance of a left ventricular assist device is assessed via hemodynamic parameters and end-organ function. This study examined effect of a left ventricular assist device on human neurophysiology. This study evaluated the time course change of cardiac autonomic activity of 3 patients during support with a left ventricular assist device before cardiac transplantation. Cardiac autonomic activity was determined by power spectral analysis of short-term heart rate variability. The heart rate variability before cardiac transplantation was compared with that on the day before left ventricular assist device implantation. The standard deviation of the mean of the R-R intervals of the electrocardiogram, an index of vagal activity, increased to 27 +/- 7 ms from 8 +/- 0.6 ms. The modulus of power spectral components increased. Low frequency (sympathetic activity) and high frequency power (vagal activity) increased by a mean of 9 and 22 times of each baseline value (low frequency power, 5.2 +/- 3.0 ms2; high frequency power, 2.1 +/- 0.7 ms2). The low over high frequency power ratio decreased substantially, indicating an improvement of cardiac sympatho-vagal balance. The study results suggest that left ventricular assist device support before cardiac transplantation may exert a favorable effect on cardiac autonomic control in patients with severe heart failure.

Autonomic predictors of recovery following surgery: A comparative study

PubMed Central

Williamson, John B.; Lewis, Greg; Grippo, Angela J.; Lamb, Damon; Harden, Emily; Handleman, Mika; Lebow, Jocelyn; Carter, C. Sue; Porges, Stephen W.

2015-01-01

Although heart rate and temperature are continuously monitored in patients during recovery following surgery, measures that extract direct manifestations of neural regulation of autonomic circuits from the beat-to-beat heart rate may be more sensitive to outcome. We explore the relationship between features of autonomic regulation and survival in the prairie vole, a small mammal, with features of vagal regulation of the heart similar to humans. Cardiac vagal regulation is manifested in the beat-to-beat heart rate variability (HRV) pattern and can be quantified by extracting measures of the amplitude of periodic oscillations associated with spontaneous breathing. Thus, monitoring beat-to-beat heart rate patterns post-surgery in the prairie vole may provide an opportunity to dynamically assess autonomic adjustments during recovery. Surgeries to implant telemetry devices to monitor body temperature and continuous ECG in prairie voles are routinely performed in our laboratory. Ten of these implanted prairie voles died within 48 h post-surgery. To compare the post-surgery autonomic trajectories with typical surviving prairie voles, the post-surgery data from 17 surviving prairie voles were randomly selected. The data are reported hourly for 27 prairie voles between 6 and 14 h (1 h before the demise of the first subject) post-surgery. Receiver operator curves were calculated hourly for each variable to evaluate sensitivity in discriminating survival. The data illustrate that measures of HRV are the most sensitive indicators. These findings provide a foundation for investigating further neural mechanisms of cardiovascular function. PMID:20451468

Heart rate complexity: A novel approach to assessing cardiac stress reactivity.

PubMed

Brindle, Ryan C; Ginty, Annie T; Phillips, Anna C; Fisher, James P; McIntyre, David; Carroll, Douglas

2016-04-01

Correlation dimension (D2), a measure of heart rate (HR) complexity, has been shown to decrease in response to acute mental stress and relate to adverse cardiovascular health. However, the relationship between stress-induced changes in D2 and HR has yet to be established. The present studies aimed to assess this relationship systematically while controlling for changes in respiration and autonomic activity. In Study 1 (N = 25) D2 decreased during stress and predicted HR reactivity even after adjusting for changes in respiration rate, and cardiac vagal tone. This result was replicated in Study 2 (N = 162) and extended by including a measure of cardiac sympathetic activity; correlation dimension remained an independent predictor of HR reactivity in a hierarchical linear model containing measures of cardiac parasympathetic and sympathetic activity and their interaction. These results suggest that correlation dimension may provide additional information regarding cardiac stress reactivity above that provided by traditional measures of cardiac autonomic function. © 2015 Society for Psychophysiological Research.

Preserved functional autonomic phenotype in adult mice overexpressing moderate levels of human alpha‐synuclein in oligodendrocytes

PubMed Central

Tank, Jens; da Costa‐Goncalves, Andrey C.; Kamer, Ilona; Qadri, Fatimunnisa; Ubhi, Kiren; Rockenstein, Edward; Diedrich, André; Masliah, Eliezer; Gross, Volkmar; Jordan, Jens

2014-01-01

Abstract Mice overexpressing human alpha‐synuclein in oligodendrocytes (MBP1‐α‐syn) recapitulate some key functional and neuropathological features of multiple system atrophy (MSA). Whether or not these mice develop severe autonomic failure, which is a key feature of human MSA, remains unknown. We explored cardiovascular autonomic regulation using long‐term blood pressure (BP) radiotelemetry and pharmacological testing. We instrumented 12 MBP1‐α‐syn mice and 11 wild‐type mice aged 9 months for radiotelemetry. Animals were tested with atropine, metoprolol, clonidine, and trimethaphan at 9 and 12 months age. We applied spectral and cross‐spectral analysis to assess heart rate (HR) and BP variability. At 9 months of age daytime BP (transgenic: 101 ± 2 vs. wild type: 99 ± 2 mmHg) and HR (497 ± 11 vs. 505 ± 16 beats/min) were similar. Circadian BP and HR rhythms were maintained. Nighttime BP (109 ± 2 vs. 108 ± 2 mmHg) and HR (575 ± 15 vs. 569 ± 14 beats/min), mean arterial BP responses to trimethaphan (−21 ± 8 vs. −10 ± 5 mmHg, P = 0.240) and to clonidine (−8 ± 3 vs. −5 ± 2 mmHg, P = 0.314) were similar. HR responses to atropine (+159 ± 24 vs. +146 ± 22 beats/min), and to clonidine (−188 ± 21 vs. −163 ± 33 beats/min) did not differ between strains. Baroreflex sensitivity (4 ± 1 vs. 4 ± 1 msec/mmHg) and HR variability (total power, 84 ± 17 vs. 65 ± 21 msec²) were similar under resting conditions and during pharmacological testing. Repeated measurements at 12 months of age provided similar results. In mice, moderate overexpression of human alpha‐synuclein in oligodendrocytes is not sufficient to induce overt autonomic failure. Additional mechanisms may be required to express the autonomic failure phenotype including higher levels of expression or more advanced age. PMID:25428949

Effect of Maturation on Hemodynamic and Autonomic Control Recovery Following Maximal Running Exercise in Highly Trained Young Soccer Players

PubMed Central

Buchheit, Martin; Al Haddad, Hani; Mendez-Villanueva, Alberto; Quod, Marc J.; Bourdon, Pitre C.

2011-01-01

The purpose of this study was to examine the effect of maturation on post-exercise hemodynamic and autonomic responses. Fifty-five highly trained young male soccer players (12–18 years) classified as pre-, circum-, or post-peak height velocity (PHV) performed a graded running test to exhaustion on a treadmill. Before (Pre) and after (5th–10th min, Post) exercise, heart rate (HR), stroke volume (SV), cardiac output (CO), arterial pressure (AP), and total peripheral resistance (TPR) were monitored. Parasympathetic (high frequency [HFRR] of HR variability (HRV) and baroreflex sensitivity [Ln BRS]) and sympathetic activity (low frequency [LFSAP] of systolic AP variability) were estimated. Post-exercise blood lactate [La]b, the HR recovery (HRR) time constant, and parasympathetic reactivation (time-varying HRV analysis) were assessed. In all three groups, exercise resulted in increased HR, CO, AP, and LFSAP (P < 0.001), decreased SV, HFRR, and Ln BRS (all P < 0.001), and no change in TPR (P = 0.98). There was no “maturation × time” interaction for any of the hemodynamic or autonomic variables (all P > 0.22). After exercise, pre-PHV players displayed lower SV, CO, and [La]b, faster HRR and greater parasympathetic reactivation compared with circum- and post-PHV players. Multiple regression analysis showed that lean muscle mass, [La]b, and Pre parasympathetic activity were the strongest predictors of HRR (r2 = 0.62, P < 0.001). While pre-PHV players displayed a faster HRR and greater post-exercise parasympathetic reactivation, maturation had little influence on the hemodynamic and autonomic responses following maximal running exercise. HRR relates to lean muscle mass, blood acidosis, and intrinsic parasympathetic function, with less evident impact of post-exercise autonomic function. PMID:22013423

Heart Rate Variability in Patients with Acute Ischemic Stroke at Different Stages of Renal Dysfunction: A Cross-sectional Observational Study.

PubMed

Wei, Lin; Zhao, Wen-Bo; Ye, Huan-Wen; Chen, Yan-Hua; Zhang, Xiao-Pei; Huang, Yan; Cai, Ye-Feng; Chen, Quan-Fu; Pan, Su-Yue

2017-03-20

Renal function is associated with mortality and functional disabilities in stroke patients, and impaired autonomic function is common in stroke, but little is known regarding its effects on stroke patients with renal dysfunction. This study sought to evaluate the association between autonomic function and stroke in patients with renal dysfunction. This study comprised 232 patients with acute ischemic stroke consecutively enrolled from February 2013 to November 2014 at Guangdong Provincial Hospital of Chinese Medicine in China. All patients recruited underwent laboratory evaluation and 24 h Holter electrocardiography (ECG). Autonomic function was measured based on the heart rate variability (HRV) using 24 h Holter ECG. Renal damage was assessed through the estimated glomerular filtration rate (eGFR), and stroke severity was rated according to the National Institutes of Health Stroke Scale (NIHSS). The Barthel index and modified Rankin score were also determined following admission. All the clinical covariates that could potentially affect autonomic outcome variables were adjusted with linear regression. In the patients with a mild or moderate decreased eGFR, the values for the standard deviation of the averaged normal-to-normal RR interval (SDANN) index (P = 0.022), very low frequency (VLF) (P = 0.043), low frequency (LF) (P = 0.023), and ratio of low-to-high frequency power (LF/HF) (P = 0.001) were significantly lower than those in the patients with a normal eGFR. A multinomial linear regression indicated that eGFR (t = 2.47, P = 0.014), gender (t = -3.60, P < 0.001), and a history of hypertension (t = -2.65, P = 0.008) were the risk factors of LF/HF; the NIHSS score (SDANN index: t = -3.83, P < 0.001; VLF: t = -3.07, P = 0.002; LF: t = -2.79, P = 0.006) and a history of diabetes (SDANN index: t = -3.58, P < 0.001; VLF: t = -2.54, P = 0.012; LF: t = -2.87, P = 0.004) were independent factors for the SDANN index, VLF, and LF; the Oxfordshire Community Stroke Project (t = -2.38, P = 0.018) was related to the SDANN index. Autonomic dysfunction is aggravated with the progression of eGFR stage in patients with acute ischemic stroke; the eGFR is an independent factor of LF/HF in the adjusted models. Stroke severity and a history of diabetes are more significantly associated with HRV in patients with acute ischemic stroke at different stages of renal dysfunction.

Cardiovagal Autonomic Function in HIV-Infected Patients with Unsuppressed HIV Viremia

PubMed Central

Chow, Dominic C.; Wood, Robert; Choi, Julia; Grandinetti, Andrew; Gerschenson, Mariana; Sriratanaviriyakul, Narin; Nakamoto, Beau; Shikuma, Cecilia; Low, Phillip

2011-01-01

Purpose HIV infection has been implicated in dysregulation of the autonomic nervous system. Method Cross-sectional study examining the relationship between the presence of persistent detectable HIV viral load with autonomic function, measured by heart rate variability (HRV). Non-virologic suppression (NVS) was defined as having a detectable viral load for at least 3 months prior to autonomic function testing. HRV was measured during the following 4 maneuvers: resting and paced respirations and sustained handgrip and tilt. Inferences on parasympathetic and sympathetic modulations were determined by analyzing time and frequency domains of HRV. Results 57 participants were enrolled in 3 groups: 22 were HIV-infected participants with HIV virologic suppression (VS; undetectable HIV viral load), 9 were HIV-infected participants who had NVS, and 26 were HIV seronegative controls. There were lower time domain parameters in the HIV-infected group as a whole compared to controls. There were no significant differences in time domain parameters among HIV-infected participants. There were no differences in frequency domain parameters during any of the maneuvers between controls and all HIV-infected participants, nor between the NVS and VS groups. Conclusion There were differences in autonomic function between HIV-infected individuals and HIV seronegative controls, but not between the NVS and VS groups. PMID:21684854

Parallel-distributed mobile robot simulator

NASA Astrophysics Data System (ADS)

Okada, Hiroyuki; Sekiguchi, Minoru; Watanabe, Nobuo

1996-06-01

The aim of this project is to achieve an autonomous learning and growth function based on active interaction with the real world. It should also be able to autonomically acquire knowledge about the context in which jobs take place, and how the jobs are executed. This article describes a parallel distributed movable robot system simulator with an autonomous learning and growth function. The autonomous learning and growth function which we are proposing is characterized by its ability to learn and grow through interaction with the real world. When the movable robot interacts with the real world, the system compares the virtual environment simulation with the interaction result in the real world. The system then improves the virtual environment to match the real-world result more closely. This the system learns and grows. It is very important that such a simulation is time- realistic. The parallel distributed movable robot simulator was developed to simulate the space of a movable robot system with an autonomous learning and growth function. The simulator constructs a virtual space faithful to the real world and also integrates the interfaces between the user, the actual movable robot and the virtual movable robot. Using an ultrafast CG (computer graphics) system (FUJITSU AG series), time-realistic 3D CG is displayed.

Cardiac Autonomic Function during Submaximal Treadmill Exercise in Adults with Down Syndrome

ERIC Educational Resources Information Center

Mendonca, Goncalo V.; Pereira, Fernando D.; Fernhall, Bo

2011-01-01

This study determined whether the cardiac autonomic function of adults with Down syndrome (DS) differs from that of nondisabled persons during submaximal dynamic exercise. Thirteen participants with DS and 12 nondisabled individuals performed maximal and submaximal treadmill tests with metabolic and heart rate (HR) measurements. Spectral analysis…

Biological implications of the hydrodynamics of swimming at or near the surface and in shallow water.

PubMed

Blake, R W

2009-03-01

The origins and effects of wave drag at and near the surface and in shallow water are discussed in terms of the dispersive waves generated by streamlined technical bodies of revolution and by semi-aquatic and aquatic animals with a view to bearing on issues regarding the design and function of autonomous surface and underwater vehicles. A simple two-dimensional model based on energy flux, allowing assessment of drag and its associated wave amplitude, is applied to surface swimming in Lesser Scaup ducks and is in good agreement with measured values. It is argued that hydrodynamic limitations to swimming at speeds associated with the critical Froude number ( approximately 0.5) and hull speed do not necessarily set biological limitations as most behaviours occur well below the hull speed. From a comparative standpoint, the need for studies on the hull displacement of different forms is emphasized. For forms in surface proximity, drag is a function of both Froude and Reynolds numbers. Whilst the depth dependence of wave drag is not particularly sensitive to Reynolds number, its magnitude is, with smaller and slower forms subject to relatively less drag augmentation than larger, faster forms that generate additional resistance due to ventilation and spray. A quasi-steady approach to the hydrodynamics of swimming in shallow water identifies substantial drag increases relative to the deeply submerged case at Froude numbers of about 0.9 that could limit the performance of semi-aquatic and aquatic animals and autonomous vehicles. A comparative assessment of fast-starting trout and upside down catfish shows that the energy losses of fast-starting fish are likely to be less for fish in surface proximity in deep water than for those in shallow water. Further work on unsteady swimming in both circumstances is encouraged. Finally, perspectives are offered as to how autonomous surface and underwater vehicles in surface proximity and shallow water could function to avoid prohibitive hydrodynamic resistance, thereby increasing their operational life.

Blood pressure responses to dietary sodium: Association with autonomic cardiovascular function in normotensive adults.

PubMed

Matthews, Evan L; Brian, Michael S; Edwards, David G; Stocker, Sean D; Wenner, Megan M; Farquhar, William B

2017-12-01

Blood pressure responses to dietary sodium vary widely person-to-person. Salt sensitive rodent models display altered autonomic function, a trait thought to contribute to poor cardiovascular health. Thus, we hypothesized that increased salt sensitivity (SS) in normotensive humans would be associated with increased muscle sympathetic nerve activity (MSNA), decreased high frequency heart rate variability (HF-HRV), and decreased baroreflex sensitivity. Healthy normotensive men and women completed 1week of high (300mmol·day -1 ) and 1week of low (20mmol·day -1 ) dietary sodium (random order) with 24h mean arterial pressure (MAP) assessed on the last day of each diet to assess SS. Participants returned to the lab under habitual sodium conditions for testing. Forty-two participants are presented in this analysis, 19 of which successful MSNA recordings were obtained (n=42: age 39±2yrs., BMI 24.3±0.5kg·(m 2 ) -1 , MAP 83±1mmHg, habitual urine sodium 93±7mmol·24h -1 ; n=19: MSNA burst frequency 20±2 bursts·min -1 ). The variables of interest were linearly regressed over the magnitude of SS. Higher SS was associated with increased MSNA (burst frequency: r=0.469, p=0.041), decreased HF-HRV (r=-0.349, p=0.046), and increased LF/HF-HRV (r=0.363, p=0.034). SS was not associated with sympathetic or cardiac baroreflex sensitivity (p>0.05). Multiple regression analysis accounting for age found that age, not SS, independently predicted HF-HRV (age adjusted no longer significant; p=0.369) and LF/HF-HRV (age adjusted p=0.273). These data suggest that age-related salt sensitivity of blood pressure in response to dietary sodium is associated with altered resting autonomic cardiovascular function. Copyright © 2017 Elsevier B.V. All rights reserved.

Autonomic and subjective responsivity to emotional images in people with dissociative seizures.

PubMed

Pick, Susannah; Mellers, John D C; Goldstein, Laura H

2018-06-01

People with dissociative seizures (DS) report a range of difficulties in emotional functioning and exhibit altered responding to emotional facial expressions in experimental tasks. We extended this research by investigating subjective and autonomic reactivity (ratings of emotional valence, arousal and skin conductance responses [SCRs]) to general emotional images in 39 people with DS relative to 42 healthy control participants, whilst controlling for anxiety, depression, cognitive functioning and, where relevant, medication use. It was predicted that greater subjective negativity and arousal and increased SCRs in response to the affective pictures would be observed in the DS group. The DS group as a whole did not differ from controls in their subjective responses of valence and arousal. However, SCR amplitudes were greater in 'autonomic responders' with DS relative to 'autonomic responders' in the control group. A positive correlation was also observed between SCRs for highly arousing negative pictures and self-reported ictal autonomic arousal, in DS 'autonomic responders'. In the DS subgroup of autonomic 'non-responders', differences in subjective responses were observed for some conditions, compared to control 'non-responders'. The findings indicate unaffected subjective responses to emotional images in people with DS overall. However, within the group of people with DS, there may be subgroups characterized by differences in emotional responding. One subgroup (i.e., 'autonomic responders') exhibit heightened autonomic responses but intact subjective emotional experience, whilst another subgroup (i.e., 'autonomic non-responders') seem to experience greater subjective negativity and arousal for some emotional stimuli, despite less frequent autonomic reactions. The current results suggest that therapeutic interventions targeting awareness and regulation of physiological arousal and subjective emotional experience could be of value in some people with this disorder. © 2017 The Authors. Journal of Neuropsychology published by John Wiley & Sons Ltd on behalf of British Psychological Society.

Convergence of Asymptotic Systems of Non-autonomous Neural Network Models with Infinite Distributed Delays

NASA Astrophysics Data System (ADS)

Oliveira, José J.

2017-10-01

In this paper, we investigate the global convergence of solutions of non-autonomous Hopfield neural network models with discrete time-varying delays, infinite distributed delays, and possible unbounded coefficient functions. Instead of using Lyapunov functionals, we explore intrinsic features between the non-autonomous systems and their asymptotic systems to ensure the boundedness and global convergence of the solutions of the studied models. Our results are new and complement known results in the literature. The theoretical analysis is illustrated with some examples and numerical simulations.

The modulation of visceral functions by somatic afferent activity.

PubMed

Sato, A; Schmidt, R F

1987-01-01

We began by briefly reviewing the historical background of neurophysiological studies of the somato-autonomic reflexes and then discussed recent studies on somatic-visceral reflexes in combination with autonomic efferent nerve activity and effector organ responses. Most of the studies that have advanced our knowledge in this area have been carried out on anesthetized animals, thus eliminating emotional factors. We would like to emphasize again that the functions of many, or perhaps all visceral organs can be modulated by somato-sympathetic or somato-parasympathetic reflex activity induced by a appropriate somatic afferent stimulation in anesthetized animals. As mentioned previously, some autonomic nervous outflow, e.g. the adrenal sympathetic nerve activity, is involved in the control of hormonal secretion. John F. Fulton wrote in his famous textbook "Physiology of the Nervous System" (1949) that the posterior pituitary neurosecretion system (i.e. for oxytocin and vasopressin) could be considered a part of the parasympathetic nervous system. In the study of body homeostasis and environmental adaptation it would seem very important to further analyze the contribution of somatic afferent input to the autonomic nervous and hormonal regulation of visceral organ activity. Also, some immunological functions have been found to be influenced by autonomic nerves or hormones (e.g. adrenal cortical hormone and catecholamines). Finally, we must take into account, as we have briefly discussed, that visceral functions can be modulated by somatic afferent input via various degrees of integration of autonomic nerves, hormones, and immunological processes. We trust that such research will be expanded to higher species of mammals, and that ultimately this knowledge of somato-visceral reflexes obtained in the physiological laboratory will become clinically useful in influencing visceral functions.

Morphology of subcortical brain nuclei is associated with autonomic function in healthy humans.

PubMed

Ruffle, James K; Coen, Steven J; Giampietro, Vincent; Williams, Steven C R; Apkarian, A Vania; Farmer, Adam D; Aziz, Qasim

2018-01-01

The autonomic nervous system (ANS) is a brain body interface which serves to maintain homeostasis by influencing a plethora of physiological processes, including metabolism, cardiorespiratory regulation and nociception. Accumulating evidence suggests that ANS function is disturbed in numerous prevalent clinical disorders, including irritable bowel syndrome and fibromyalgia. While the brain is a central hub for regulating autonomic function, the association between resting autonomic activity and subcortical morphology has not been comprehensively studied and thus was our aim. In 27 healthy subjects [14 male and 13 female; mean age 30 years (range 22-53 years)], we quantified resting ANS function using validated indices of cardiac sympathetic index (CSI) and parasympathetic cardiac vagal tone (CVT). High resolution structural magnetic resonance imaging scans were acquired, and differences in subcortical nuclei shape, that is, 'deformation', contingent on resting ANS activity were investigated. CSI positively correlated with outward deformation of the brainstem, right nucleus accumbens, right amygdala and bilateral pallidum (all thresholded to corrected P < 0.05). In contrast, parasympathetic CVT negatively correlated with inward deformation of the right amygdala and pallidum (all thresholded to corrected P < 0.05). Left and right putamen volume positively correlated with CVT (r = 0.62, P = 0.0047 and r = 0.59, P = 0.008, respectively), as did the brainstem (r = 0.46, P = 0.049). These data provide novel evidence that resting autonomic state is associated with differences in the shape and volume of subcortical nuclei. Thus, subcortical morphological brain differences in various disorders may partly be attributable to perturbation in autonomic function. Further work is warranted to investigate these findings in clinical populations. Hum Brain Mapp 39:381-392, 2018. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

University EFL Learners' Perceptions of Their Autonomous Learning Responsibilities and Abilities

ERIC Educational Resources Information Center

Abdel Razeq, Anwar Ahmad

2014-01-01

This study investigated the readiness of university students for autonomous learning of English as a foreign language. Data was collected using questionnaires and interviews. The study assessed learners' readiness for autonomous learning across three dimensions: a) learners' perceptions of their educational responsibilities; b) learners' abilities…

Hypnosis in the Treatment of Major Depression: An Analysis of Heart Rate Variability.

PubMed

Chen, Xiuwen; Yang, Rongqian; Ge, Lulu; Luo, Jie; Lv, Ruixue

2017-01-01

Hypnosis is an adjuvant treatment of major depression (MD). Heart rate variability (HRV) can assess the autonomic nervous system, which is associated with MD, and HRV is decreased in MD patients. There is a lack of research on HRV changes before, during, and after the use of hypnosis in MD patients. A total of 21 MD patients participated in this study, and 5-minute electrocardiograms were recorded before, during, and after hypnosis. Compared with the prehypnotic condition, HRV parameters significantly (p < .01) increased in the hypnotic and posthypnotic conditions. The results suggest that hypnosis treatment should bring some functional improvement to the autonomic nervous system. HRV is potentially a useful tool that quantifies the physiological impact of hypnosis treatment in MD patients.

Assessment of the Cardiac Autonomic Nervous System in Mercury-Exposed Individuals via Post-Exercise Heart Rate Recovery.

PubMed

Yilmaz, Omer Hinc; Karakulak, Ugur Nadir; Tutkun, Engin; Bal, Ceylan; Gunduzoz, Meside; Ercan Onay, Emine; Ayturk, Mehmet; Tek Ozturk, Mujgan; Alaguney, Mehmet Erdem

The aim of this study was to assess exercise heart rate recovery (HRR) indices in mercury-exposed individuals when evaluating their cardiac autonomic function. Twenty-eight mercury-exposed individuals and 28 healthy controls were enrolled. All the subjects underwent exercise testing and transthoracic echocardiography. The HRR indices were calculated by subtracting the first- (HRR1), second- (HRR2) and third-minute (HRR3) heart rates from the maximal heart rate. The two groups were evaluated in terms of exercise test parameters, especially HRR, and a correlation analysis was performed between blood, 24-hour urine and hair mercury levels and the test parameters. The mercury-exposed and control groups were similar in age (37.2 ± 6.6 vs. 36.9 ± 9.0 years), had an identical gender distribution (16 females and 12 males) and similar left ventricular ejection fractions (65.5 ± 3.1 vs. 65.4 ± 3.1%). The mean HRR1 [25.6 ± 6.5 vs. 30.3 ± 8.2 beats per min (bpm); p = 0.009], HRR2 (43.5 ± 5.3 vs. 47.8 ± 5.5 bpm; p = 0.010) and HRR3 (56.8 ± 5.1 vs. 59.4 ± 6.3 bpm; p = 0.016) values were significantly lower in the mercury-exposed group than in the healthy controls. However, there were no significant correlations between blood, urine and hair mercury levels and exercise test parameters. Mercury-exposed individuals had lower HRR indices than normal subjects. In these individuals, mercury exposure measurements did not show correlations with the exercise test parameters, but age did show a negative correlation with these parameters. Therefore, cardiac autonomic functions might be involved in cases of mercury exposure. © 2016 S. Karger AG, Basel.

[Effects of inflammation and stimulant diets on functions of autonomic nervous system (author's transl)].

PubMed

Akaeda, H; Nagai, K; Okuda, Y; Shinoto, M; Okuda, H

1981-06-01

In usual medical consultation, we have been met a lot of female patients suffering from disturbances of autonomic nervous system such as headache, shoulder-ache and so on. Experiments were designed to elucidate whether or not these disturbances of autonomic nervous system were induced by inflammation and accelerated by stimulant diets. Functions of autonomic nervous system were examined by lipolysis in rat epididymal adipose tissue which was partly controlled by sympathetic nervous system. It was found that free fatty acid release from the epididymal adipose tissue was considerably elevated by inflammation which was formed in abdominal wall or in abdominal cavity or oral administration of stimulant diets such as red pepper and white pepper, and that such elevation of lipolysis was significantly reduced by resection of the autonomic nerve. These results indicated that the inflammation and the stimulant diets induced excitement of sympathetic nerve which controlled the epididymal adipose tissue. Experiments were now in progress to clarify relationship between such excitement of sympathetic nervous system induced by the inflammation or by the stimulant diet and irregular complaints due to disturbances of autonomic nervous system.

Autonomous Mars ascent and orbit rendezvous for earth return missions

NASA Technical Reports Server (NTRS)

Edwards, H. C.; Balmanno, W. F.; Cruz, Manuel I.; Ilgen, Marc R.

1991-01-01

The details of tha assessment of autonomous Mars ascent and orbit rendezvous for earth return missions are presented. Analyses addressing navigation system assessments, trajectory planning, targeting approaches, flight control guidance strategies, and performance sensitivities are included. Tradeoffs in the analysis and design process are discussed.

Autonomous learning by simple dynamical systems with a discrete-time formulation

NASA Astrophysics Data System (ADS)

Bilen, Agustín M.; Kaluza, Pablo

2017-05-01

We present a discrete-time formulation for the autonomous learning conjecture. The main feature of this formulation is the possibility to apply the autonomous learning scheme to systems in which the errors with respect to target functions are not well-defined for all times. This restriction for the evaluation of functionality is a typical feature in systems that need a finite time interval to process a unit piece of information. We illustrate its application on an artificial neural network with feed-forward architecture for classification and a phase oscillator system with synchronization properties. The main characteristics of the discrete-time formulation are shown by constructing these systems with predefined functions.

A Double-Blind Atropine Trial for Active Learning of Autonomic Function

ERIC Educational Resources Information Center

Fry, Jeffrey R.; Burr, Steven A.

2011-01-01

Here, we describe a human physiology laboratory class measuring changes in autonomic function over time in response to atropine. Students use themselves as subjects, generating ownership and self-interest in the learning as well as directly experiencing the active link between physiology and pharmacology in people. The class is designed to…

Effects of antipsychotic drugs on cardiovascular variability in participants with bipolar disorder

PubMed Central

Linder, Jonathan R.; Sodhi, Simrit K.; Haynes, William G.; Fiedorowicz, Jess G.

2014-01-01

Objective The risk for cardiovascular diseases is elevated in persons with bipolar disorder. However, it remains unknown how much of this excess risk is secondary to pharmacologic treatment. We tested the hypothesis that current and cumulative antipsychotic drug exposure is associated with increased cardiovascular risk as indicated by lower heart rate variability (HRV) and increased blood pressure variability (BPV). Methods 55 individuals with bipolar disorder (33±7 years; 67% female) underwent non-invasive electrocardiogram assessment of time- and frequency-domain HRV, as well as BPV analysis. Medication histories were obtained through systematic review of pharmacy records for the past five years. Results Current antipsychotic exposure was associated with lower SDNN. Second generation antipsychotics were associated with lower SDNN and RMSSD. There was no significant relationship between five-year antipsychotic exposure and HRV in subjects with bipolar disorder. Exploratory analysis revealed a possible link between SSRI exposure and increased low frequency spectral HRV. Conclusions Current antipsychotic use (particularly second generation antipsychotics with high affinities for the D2S receptor) is associated with reduced autonomic-mediated variability of heart rate. The absence of an association with cumulative exposure suggests that the effects are acute in onset, and may therefore relate more to altered autonomic function than structural cardiovascular abnormalities. Future studies should prospectively examine effects of these antipsychotics on autonomic function. PMID:24590543

Cardio-pulmonary fitness test by ultra-short heart rate variability.

PubMed

Aslani, Arsalan; Aslani, Amir; Kheirkhah, Jalal; Sobhani, Vahid

2011-10-01

It is known that exercise induces cardio-respiratory autonomic modulation. The aim of this study was to assess the cardio-pulmonary fitness by ultra-short heart rate variability. Study population was divided into 3 groups: Group-1 (n = 40) consisted of military sports man. Group-2 (n = 40) were healthy age-matched sedentary male subjects with normal body mass index [BMI = 19 - 25 kg/m(2)). Group-3 (n = 40) were healthy age-matched obese male subjects [BMI > 29 kg/m(2)). Standard deviation of normal-to-normal QRS intervals (SDNN) was recorded over 15 minutes. Bruce protocol treadmill test was used; and, maximum oxygen consumption (VO(2)max) was calculated. WHEN THE STUDY POPULATION WAS DIVIDED INTO QUARTILES OF SDNN (FIRST QUARTILE: < 60 msec; second quartile: > 60 and < 100 msec; third quartile: > 100 and <140 msec; and fourth quartile: >140 msec), progressive increase was found in VO(2)max; and, SDNN was significantly linked with estimated VO(2)max. In conclusion, the results of this study demonstrate that exercise training improves cardio-respiratory autonomic function (and increases heart rate variability). Improvement in cardio-respiratory autonomic function seems to translate into a lower rate of long term mortality. Ultra-short heart rate variability is a simple cardio-pulmonary fitness test which just requires 15 minutes, and involves no exercise such as in the treadmill or cycle test.

Presenting the facts about smoking to adolescents: effects of an autonomy-supportive style.

PubMed

Williams, G C; Cox, E M; Kouides, R; Deci, E L

1999-09-01

To test the self-determination model of health-related behavior by examining whether the degree to which adolescents experience an appeal to not smoke as autonomy supportive would affect their autonomous motivation for not smoking and, in turn, their behavior of either refraining from smoking or smoking less, and to validate the measures of perceived autonomy support and autonomous motivation for not smoking. Two studies of physicians presenting information about not smoking using 2 message styles, 1 of which was designed to be more autonomy supportive. The preliminary study involved nonrandomized assignment to message style and only immediate assessment of perceptions, motivation, and behavior, while the primary study involved randomized assignment and 4-month longitudinal assessments. Nearly 400 ninth- through 12th-grade students at 2 suburban high schools in upstate New York. Adolescents' perceptions of the presentations' autonomy supportiveness of the presenters, as well as adolescents' autonomous motivation for not smoking and their self-reports of smoking. The primary study also assessed change in students' autonomous motivation and change in their self-reported smoking during 4 months. In both studies, the measures were reliable and valid. Students perceived significantly (P = .04 and P<.001, respectively) greater autonomy support in the "It's Your Choice" presentation, after controlling for whether the students were smokers. Perceived autonomy supportiveness of the presentation was positively correlated with autonomous reasons for not smoking in the preliminary study and with increases in autonomous motivation for not smoking in the primary study. Change in autonomous reasons for not smoking significantly (P<.001) predicted reduction in smoking during 4 months. When adolescents perceived messages about not smoking as autonomy supportive, they had more autonomous motivation for not smoking, and that, in turn, predicted a decrease in their self-reports of smoking.

Influence of hydrotherapy on clinical and cardiac autonomic function in migraine patients.

PubMed

Sujan, M U; Rao, M Raghavendra; Kisan, Ravikiran; Abhishekh, Hulegar A; Nalini, Atchayaram; Raju, Trichur R; Sathyaprabha, T N

2016-01-01

Migraine is associated with autonomic symptoms. The growing body of literature suggests that the dysfunctional autonomic nervous system might play a pivotal role in the pathogenesis of migraine. Thermal therapies have been hypothesized to modulate these changes and alleviate pain. However, data regarding the efficacy of hydrotherapy in migraine remain scant. We evaluated the effect of add on hydrotherapy procedure (a hot arm and foot bath with ice massage to head) in migraine patients. Forty chronic migraine patients fulfilling the International Classification of Headache Disorders II criteria were recruited from the neurology outpatient clinic. Patients were randomized to receive either hydrotherapy plus conventional pharmacological care (n = 20) or conventional medication only (n = 20). Hydrotherapy group received treatment with hot arm and foot bath (103°F to 110°F) and ice massage to head daily for 20 min for 45 days. Patients were assessed using headache impact test (HIT), visual analog scale for pain and cardiac autonomic function by heart rate variability (HRV) before and after intervention period. There was a significant decrease in HIT score, frequency, and intensity of headaches following treatment in both the groups. However, it was more evident in add on hydrotherapy group compared to pharmacological treatment alone group. There was also significant improvement in the HRV parameters. In particular, there was a significant decrease in heart rate (P = 0.017), increase in high frequency (HF) (P = 0.014) and decrease in low frequency/HF ratio (P = 0.004) in add on hydrotherapy group. Our study shows that add on hydrotherapy enhanced the vagal tone in addition to reducing the frequency and intensity of headaches in migraine patients.

Influence of hydrotherapy on clinical and cardiac autonomic function in migraine patients

PubMed Central

Sujan, M. U.; Rao, M. Raghavendra; Kisan, Ravikiran; Abhishekh, Hulegar A.; Nalini, Atchayaram; Raju, Trichur R.; Sathyaprabha, T. N.

2016-01-01

Background: Migraine is associated with autonomic symptoms. The growing body of literature suggests that the dysfunctional autonomic nervous system might play a pivotal role in the pathogenesis of migraine. Thermal therapies have been hypothesized to modulate these changes and alleviate pain. However, data regarding the efficacy of hydrotherapy in migraine remain scant. We evaluated the effect of add on hydrotherapy procedure (a hot arm and foot bath with ice massage to head) in migraine patients. Methods: Forty chronic migraine patients fulfilling the International Classification of Headache Disorders II criteria were recruited from the neurology outpatient clinic. Patients were randomized to receive either hydrotherapy plus conventional pharmacological care (n = 20) or conventional medication only (n = 20). Hydrotherapy group received treatment with hot arm and foot bath (103°F to 110°F) and ice massage to head daily for 20 min for 45 days. Patients were assessed using headache impact test (HIT), visual analog scale for pain and cardiac autonomic function by heart rate variability (HRV) before and after intervention period. Results: There was a significant decrease in HIT score, frequency, and intensity of headaches following treatment in both the groups. However, it was more evident in add on hydrotherapy group compared to pharmacological treatment alone group. There was also significant improvement in the HRV parameters. In particular, there was a significant decrease in heart rate (P = 0.017), increase in high frequency (HF) (P = 0.014) and decrease in low frequency/HF ratio (P = 0.004) in add on hydrotherapy group. Conclusion: Our study shows that add on hydrotherapy enhanced the vagal tone in addition to reducing the frequency and intensity of headaches in migraine patients. PMID:26933356

Integrity of central nervous function in diabetes mellitus assessed by resting state EEG frequency analysis and source localization.

PubMed

Frøkjær, Jens B; Graversen, Carina; Brock, Christina; Khodayari-Rostamabad, Ahmad; Olesen, Søren S; Hansen, Tine M; Søfteland, Eirik; Simrén, Magnus; Drewes, Asbjørn M

2017-02-01

Diabetes mellitus (DM) is associated with structural and functional changes of the central nervous system. We used electroencephalography (EEG) to assess resting state cortical activity and explored associations to relevant clinical features. Multichannel resting state EEG was recorded in 27 healthy controls and 24 patients with longstanding DM and signs of autonomic dysfunction. The power distribution based on wavelet analysis was summarized into frequency bands with corresponding topographic mapping. Source localization analysis was applied to explore the electrical cortical sources underlying the EEG. Compared to controls, DM patients had an overall decreased EEG power in the delta (1-4Hz) and gamma (30-45Hz) bands. Topographic analysis revealed that these changes were confined to the frontal region for the delta band and to central cortical areas for the gamma band. Source localization analysis identified sources with reduced activity in the left postcentral gyrus for the gamma band and in right superior parietal lobule for the alpha1 (8-10Hz) band. DM patients with clinical signs of autonomic dysfunction and gastrointestinal symptoms had evidence of altered resting state cortical processing. This may reflect metabolic, vascular or neuronal changes associated with diabetes. Copyright © 2017 Elsevier Inc. All rights reserved.

Impaired neural structure and function contributing to autonomic symptoms in congenital central hypoventilation syndrome.

PubMed

Harper, Ronald M; Kumar, Rajesh; Macey, Paul M; Harper, Rebecca K; Ogren, Jennifer A

2015-01-01

Congenital central hypoventilation syndrome (CCHS) patients show major autonomic alterations in addition to their better-known breathing deficiencies. The processes underlying CCHS, mutations in the PHOX2B gene, target autonomic neuronal development, with frame shift extent contributing to symptom severity. Many autonomic characteristics, such as impaired pupillary constriction and poor temperature regulation, reflect parasympathetic alterations, and can include disturbed alimentary processes, with malabsorption and intestinal motility dyscontrol. The sympathetic nervous system changes can exert life-threatening outcomes, with dysregulation of sympathetic outflow leading to high blood pressure, time-altered and dampened heart rate and breathing responses to challenges, cardiac arrhythmia, profuse sweating, and poor fluid regulation. The central mechanisms contributing to failed autonomic processes are readily apparent from structural and functional magnetic resonance imaging studies, which reveal substantial cortical thinning, tissue injury, and disrupted functional responses in hypothalamic, hippocampal, posterior thalamic, and basal ganglia sites and their descending projections, as well as insular, cingulate, and medial frontal cortices, which influence subcortical autonomic structures. Midbrain structures are also compromised, including the raphe system and its projections to cerebellar and medullary sites, the locus coeruleus, and medullary reflex integrating sites, including the dorsal and ventrolateral medullary nuclei. The damage to rostral autonomic sites overlaps metabolic, affective and cognitive regulatory regions, leading to hormonal disruption, anxiety, depression, behavioral control, and sudden death concerns. The injuries suggest that interventions for mitigating hypoxic exposure and nutrient loss may provide cellular protection, in the same fashion as interventions in other conditions with similar malabsorption, fluid turnover, or hypoxic exposure.

Autonomic Correlates of Speech versus Nonspeech Tasks in Children and Adults

ERIC Educational Resources Information Center

Arnold, Hayley S.; MacPherson, Megan K.; Smith, Anne

2014-01-01

Purpose: To assess autonomic arousal associated with speech and nonspeech tasks in school-age children and young adults. Method: Measures of autonomic arousal (electrodermal level, electrodermal response amplitude, blood pulse volume, and heart rate) were recorded prior to, during, and after the performance of speech and nonspeech tasks by twenty…

Self-Assessment Exercises in Continuum Mechanics with Autonomous Learning

ERIC Educational Resources Information Center

Marcé-Nogué, Jordi; Gil, LLuís; Pérez, Marco A.; Sánchez, Montserrat

2013-01-01

The main objective of this work is to generate a set of exercises to improve the autonomous learning in "Continuum Mechanics" through a virtual platform. Students will have to resolve four exercises autonomously related to the subject developed in class and they will post the solutions on the virtual platform within a deadline. Students…

Are Autonomous and Controlled Motivations School-Subjects-Specific?

PubMed

Chanal, Julien; Guay, Frédéric

2015-01-01

This research sought to test whether autonomous and controlled motivations are specific to school subjects or more general to the school context. In two cross-sectional studies, 252 elementary school children (43.7% male; mean age = 10.7 years, SD = 1.3 years) and 334 junior high school children (49.7% male, mean age = 14.07 years, SD = 1.01 years) were administered a questionnaire assessing their motivation for various school subjects. Results based on structural equation modeling using the correlated trait-correlated method minus one model (CTCM-1) showed that autonomous and controlled motivations assessed at the school subject level are not equally school-subject-specific. We found larger specificity effects for autonomous (intrinsic and identified) than for controlled (introjected and external) motivation. In both studies, results of factor loadings and the correlations with self-concept and achievement demonstrated that more evidence of specificity was obtained for autonomous regulations than for controlled ones. These findings suggest a new understanding of the hierarchical and multidimensional academic structure of autonomous and controlled motivations and of the mechanisms involved in the development of types of regulations for school subjects.

Are Autonomous and Controlled Motivations School-Subjects-Specific?

PubMed Central

Chanal, Julien; Guay, Frédéric

2015-01-01

This research sought to test whether autonomous and controlled motivations are specific to school subjects or more general to the school context. In two cross-sectional studies, 252 elementary school children (43.7% male; mean age = 10.7 years, SD = 1.3 years) and 334 junior high school children (49.7% male, mean age = 14.07 years, SD = 1.01 years) were administered a questionnaire assessing their motivation for various school subjects. Results based on structural equation modeling using the correlated trait-correlated method minus one model (CTCM-1) showed that autonomous and controlled motivations assessed at the school subject level are not equally school-subject-specific. We found larger specificity effects for autonomous (intrinsic and identified) than for controlled (introjected and external) motivation. In both studies, results of factor loadings and the correlations with self-concept and achievement demonstrated that more evidence of specificity was obtained for autonomous regulations than for controlled ones. These findings suggest a new understanding of the hierarchical and multidimensional academic structure of autonomous and controlled motivations and of the mechanisms involved in the development of types of regulations for school subjects. PMID:26247788

Fatigue correlates with the decrease in parasympathetic sinus modulation induced by a cognitive challenge

PubMed Central

2014-01-01

Background It is known that enhancement of sympathetic nerve activity based on a decrease in parasympathetic nerve activity is associated with fatigue induced by mental tasks lasting more than 30 min. However, to measure autonomic nerve function and assess fatigue levels in both clinical and industrial settings, shorter experimental durations and more sensitive measurement methods are needed. The aim of the present study was to establish an improved method for inducing fatigue and evaluating the association between it and autonomic nerve activity. Methods Twenty-eight healthy female college students participated in the study. We used a kana pick-out test (KPT) as a brief verbal cognitive task and recorded electrocardiography (ECG) to measure autonomic nerve activity. The experimental design consisted of a 16-min period of ECG: A pre-task resting state with eyes open for 3 min and eyes closed for 3 min, the 4-min KPT, and a post-task resting state with eyes open for 3 min and eyes closed for 3 min. Results Baseline fatigue sensation, measured by a visual analogue scale before the experiment, was associated with the decrease in parasympathetic sinus modulation, as indicated the by ratio of low-frequency component power (LF) to high-frequency component power (HF), during the KPT. The LF/HF ratio during the post-KPT rest with eyes open tended to be greater than the ratio during the KPT and correlated with fatigue sensation. Fatigue sensation was correlated negatively with log-transformed HF, which is an index of parasympathetic sinus modulation, during the post-KPT rest with eyes open. Conclusions The methods described here are useful for assessing the association between fatigue sensation and autonomic nerve activity using a brief cognitive test in healthy females. PMID:25069864

The development of an assessment tool for the mobility of lightweight autonomous vehicles on coastal terrain

NASA Astrophysics Data System (ADS)

Worley, Marilyn E.; Ren, Ping; Sandu, Corina; Hong, Dennis

2007-04-01

This study focuses on developing an assessment tool for the performance prediction of lightweight autonomous vehicles with varying locomotion platforms on coastal terrain involves three segments. A table based on the House of Quality shows the relationships - high, low, or adverse - between mission profile requirements and general performance measures and geometries of vehicles under consideration for use. This table, when combined with known values for vehicle metrics, provides information for an index formula used to quantitatively compare the mobility of a user-chosen set of vehicles, regardless of their methods of locomotion. To study novel forms of locomotion, and to compare their mobility and performance with more traditional wheeled and tracked vehicles, several new autonomous vehicles - bipedal, self-excited dynamic tripedal, active spoke-wheel - are currently under development. While the terramechanics properties of wheeled and tracked vehicles, such as the contact patch pressure distribution, have been understood and models have been developed for heavy vehicles, the feasibility of extrapolating them to the analysis of light vehicles is still under analysis. wheeled all-terrain vehicle and a lightweight autonomous tracked vehicle have been tested for effects of sand gradation, vehicle speed, and vehicle payload on measures of pressure and sinkage in the contact patch, and preliminary analysis is presented on the sinkage of the wheeled all-terrain vehicle. These three segments - development of the comparison matrix and indexing function, modeling and development of novel forms of locomotion, and physical experimentation of lightweight tracked and wheeled vehicles on varying terrain types for terramechanic model validation - combine to give an overall picture of mobility that spans across different forms of locomotion.

Alternative Fuels Data Center

Science.gov Websites

Autonomous Vehicle Regulations and Committee A fully autonomous vehicle is defined as a vehicle tactical control functions of the vehicle at any time.Effective December 1, 2017, the operator of a fully autonomous vehicle is not required to be licensed to operate a motor vehicle. A person may operate a fully

Architecture of autonomous systems

NASA Technical Reports Server (NTRS)

Dikshit, Piyush; Guimaraes, Katia; Ramamurthy, Maya; Agrawala, Ashok; Larsen, Ronald L.

1986-01-01

Automation of Space Station functions and activities, particularly those involving robotic capabilities with interactive or supervisory human control, is a complex, multi-disciplinary systems design problem. A wide variety of applications using autonomous control can be found in the literature, but none of them seem to address the problem in general. All of them are designed with a specific application in mind. In this report, an abstract model is described which unifies the key concepts underlying the design of automated systems such as those studied by the aerospace contractors. The model has been kept as general as possible. The attempt is to capture all the key components of autonomous systems. With a little effort, it should be possible to map the functions of any specific autonomous system application to the model presented here.

Architecture of autonomous systems

NASA Technical Reports Server (NTRS)

Dikshit, Piyush; Guimaraes, Katia; Ramamurthy, Maya; Agrawala, Ashok; Larsen, Ronald L.

1989-01-01

Automation of Space Station functions and activities, particularly those involving robotic capabilities with interactive or supervisory human control, is a complex, multi-disciplinary systems design problem. A wide variety of applications using autonomous control can be found in the literature, but none of them seem to address the problem in general. All of them are designed with a specific application in mind. In this report, an abstract model is described which unifies the key concepts underlying the design of automated systems such as those studied by the aerospace contractors. The model has been kept as general as possible. The attempt is to capture all the key components of autonomous systems. With a little effort, it should be possible to map the functions of any specific autonomous system application to the model presented here.

Sweat testing to evaluate autonomic function

PubMed Central

Illigens, Ben M.W.; Gibbons, Christopher H.

2011-01-01

Sudomotor dysfunction is one of the earliest detectable neurophysiologic abnormalities in distal small fiber neuropathy. Traditional neurophysiologic measurements of sudomotor function include thermoregulatory sweat testing (TST), quantitative sudomotor axon reflex testing (QSART), silicone impressions, the sympathetic skin response (SSR), and the recent addition of quantitative direct and indirect axon reflex testing (QDIRT). These testing techniques, when used in combination, can detect and localized pre- and postganglionic lesions, can provide early diagnosis of sudomotor dysfunction and can monitor disease progression or disease recovery. In this article, we review the common tests available for assessment of sudomotor function, detail the testing methodology, review the limitations and provide examples of test results. PMID:18989618

High-Intensity Progressive Resistance Training Increases Strength With No Change in Cardiovascular Function and Autonomic Neural Regulation in Older Adults.

PubMed

Kanegusuku, Hélcio; Queiroz, Andréia C; Silva, Valdo J; de Mello, Marco T; Ugrinowitsch, Carlos; Forjaz, Cláudia L

2015-07-01

The effects of high-intensity progressive resistance training (HIPRT) on cardiovascular function and autonomic neural regulation in older adults are unclear. To investigate this issue, 25 older adults were randomly divided into two groups: control (CON, N = 13, 63 ± 4 years; no training) and HIPRT (N = 12, 64 ± 4 years; 2 sessions/week, 7 exercises, 2–4 sets, 10–4 RM). Before and after four months, maximal strength, quadriceps cross-sectional area (QCSA), clinic and ambulatory blood pressures (BP), systemic hemodynamics, and cardiovascular autonomic modulation were measured. Maximal strength and QCSA increased in the HIPRT group and did not change in the CON group. Clinic and ambulatory BP, cardiac output, systemic vascular resistance, stroke volume, heart rate, and cardiac sympathovagal balance did not change in the HIPRT group or the CON group. In conclusion, HIPRT was effective at increasing muscle mass and strength without promoting changes in cardiovascular function or autonomic neural regulation.

System and method of self-properties for an autonomous and automatic computer environment

NASA Technical Reports Server (NTRS)

Sterritt, Roy (Inventor); Hinchey, Michael G. (Inventor)

2010-01-01

Systems, methods and apparatus are provided through which in some embodiments self health/urgency data and environment health/urgency data may be transmitted externally from an autonomic element. Other embodiments may include transmitting the self health/urgency data and environment health/urgency data together on a regular basis similar to the lub-dub of a heartbeat. Yet other embodiments may include a method for managing a system based on the functioning state and operating status of the system, wherein the method may include processing received signals from the system indicative of the functioning state and the operating status to obtain an analysis of the condition of the system, generating one or more stay alive signals based on the functioning status and the operating state of the system, transmitting the stay-alive signal, transmitting self health/urgency data, and transmitting environment health/urgency data. Still other embodiments may include an autonomic element that includes a self monitor, a self adjuster, an environment monitor, and an autonomic manager.

High-frequency transformation of a methylotrophic yeast, Candida boidinii, with autonomously replicating plasmids which are also functional in Saccharomyces cerevisiae.

PubMed

Sakai, Y; Goh, T K; Tani, Y

1993-06-01

We have developed a transformation system which uses autonomous replicating plasmids for a methylotrophic yeast, Candida boidinii. Two autonomous replication sequences, CARS1 and CARS2, were newly cloned from the genome of C. boidinii. Plasmids having both a CARS fragment and the C. boidinii URA3 gene transformed C. boidinii ura3 cells to Ura+ phenotype at frequencies of up to 10(4) CFU/micrograms of DNA. From Southern blot analysis, CARS plasmids seemed to exist in polymeric forms as well as in monomeric forms in C. boidinii cells. The C. boidinii URA3 gene was overexpressed in C. boidinii on these CARS vectors. CARS1 and CARS2 were found to function as an autonomous replicating element in Saccharomyces cerevisiae as well. Different portions of the CARS1 sequence were needed for autonomous replicating activity in C. boidinii and S. cerevisiae. C. boidinii could also be transformed with vectors harboring a CARS fragment and the S. cerevisiae URA3 gene.

Idiopathic orthostatic intolerance and postural tachycardia syndromes

NASA Technical Reports Server (NTRS)

Jacob, G.; Biaggioni, I.; Robertson, D. (Principal Investigator)

1999-01-01

Upright posture imposes a substantial gravitational stress on the body, for which we are able to compensate, in large part because of the autonomic nervous system. Alteration in autonomic function, therefore, may lead to orthostatic intolerance. On one extreme, patients with autonomic failure caused by degenerative loss of autonomic function are severely disabled by orthostatic hypotension and may faint whenever they stand up. Fortunately, such patients are relatively rare. On the other hand, disabling orthostatic intolerance can develop in otherwise normal young people. These patients can be severely impaired by symptoms of fatigue, tachycardia, and shortness of breath when they stand up. The actual incidence of this disorder is unknown, but these patients make up the largest group of patients referred to centers that specialize in autonomic disorders. We will review recent advances made in the understanding of this condition, potential pathophysiological mechanisms that contribute to orthostatic intolerance, therapeutic alternatives currently available for the management of these patients, and areas in which more research is needed.

CLINICAL AUTONOMIC NEUROPHYSIOLOGY AND THE MALE SEXUAL RESPONSE: AN OVERVIEW

PubMed Central

Yang, Claire C.; Jiang, Xiaogang

2009-01-01

Introduction Clinical neurophysiology is the study of the human nervous system through the recording of bioelectrical activity. In the realm of male sexual functioning, this includes using electrophysiologic techniques to study the nerves subserving erection, emission, ejaculation, and orgasm. Aim To introduce the reader to the principles of clinical neurophysiology as they relate to the male sexual response, particularly erection. Methods We review the pertinent autonomic neuroanatomy and neurophysiology of reflexes relevant to the male sexual response, as well as summarize the genital electrodiagnostic tests that are being used to interrogate the autonomic innervation pertinent to male sexual functioning. Conclusions The male sexual response is a coordinated series of interactions between the somatic and the autonomic nervous systems. Measurement of the autonomically mediated portions of the sexual reflexes is of great clinical interest, particularly in relation to erection. Advances in clinical electrodiagnostics now allow for consistent recording of evoked and spontaneous intra-penile electrical activity. However, before broad and widespread use of these techniques is possible, more investigations are needed. PMID:19267845

[National survey of preoperative management and patient selection in ambulatory surgery centers].

PubMed

Papaceit, J; Olona, M; Ramón, C; García-Aguado, R; Rodríguez, R; Rull, M

2003-01-01

The objective of this study was to determine both the selection and preparation criteria in patients in various Spanish ambulatory surgery centers, as well as the impact of these criteria on their results. The results were compared according to the type of functional structure of the units (autonomous or integrated). We performed a cross sectional, descriptive study through postal survey. The survey contained the following items: type of unit, surgical procedures, selection criteria, preoperative assessment and management, and qualitative and quantitative indexes of the activity performed in 2000. A total of 123 units were included with a response rate of 39%. The selection criteria showed a high degree of consensus. The outpatient anesthesia clinic was used for preoperative assessment by 97.9% of the units. Most units routinely requested preoperative tests (hemostasis and hemogram by 89%; biochemical parameters by 72.9%) and to a lesser extent chest X-ray (33.3%) and electrocardiogram (35.4%). The introduction of procedures for the management of coexisting diseases was scarce (25-64.6%). Units using the outpatient anesthesia clinic in all patients had a lower cancellation rate (1.5% vs 4.4%). Autonomous units were significantly more likely to accept patients with high surgical-anesthetic risk than integrated units. Autonomous units also showed a significantly lower number of admissions (1.2% vs 1.9%, p = 0.003), mean stay (240 min vs 367 min, p = 0.002), and recovery time (150 min vs 212 min, p = 0.001) than integrated units. No statistically significant differences were found in the remaining parameters. Scientifically based protocols for patient selection, preoperative assessment and perioperative management of distinct processes and for the rational use of laboratory tests should be more widely used. The need for an outpatient anesthesia clinic for preoperative assessment was notable. The results of our survey indicate that better results in performance indexes are achieved in autonomous ambulatory surgery units than in integrated units. Given the possibility of defining and validating quality standards, further multicenter studies should be performed.

Central autonomic nervous system response to autonomic challenges is altered in patients with a previous episode of Takotsubo cardiomyopathy.

PubMed

Pereira, Vitor H; Marques, Paulo; Magalhães, Ricardo; Português, João; Calvo, Lucy; Cerqueira, João J; Sousa, Nuno

2016-04-01

Takotsubo cardiomyopathy is an intriguing disease characterized by acute transient left ventricular dysfunction usually triggered by an episode of severe stress. The excessive levels of catecholamines and the overactivation of the sympathetic system are believed to be the main pathophysiologic mechanisms of Takotsubo cardiomyopathy, but it is unclear whether there is a structural or functional signature of the disease. In this sense, our aim was to characterize the central autonomic system response to autonomic challenges in patients with a previous episode of Takotsubo cardiomyopathy when compared with a control group of healthy volunteers. Functional magnetic resonance imaging (fMRI) was performed in four patients with a previous episode of Takotsubo cardiomyopathy (average age of 67 ± 12 years) and in eight healthy volunteers (average age of 66 ± 5 years) while being submitted to different autonomic challenges (cold exposure and Valsalva manoeuvre). The fMRI analysis revealed a significant variation of the blood oxygen level dependent signal triggered by the Valsalva manoeuvre in specific areas of the brain involved in the cortical control of the autonomic system and significant differences in the pattern of activation of the insular cortex, amygdala and the right hippocampus between patients with Takotsubo cardiomyopathy and controls, even though these regions did not present significant volumetric changes. The central autonomic response to autonomic challenges is altered in patients with Takotsubo cardiomyopathy, thus suggesting a dysregulation of the central autonomic nervous system network. Subsequent studies are needed to unveil whether these alterations are causal or predisposing factors to Takotsubo cardiomyopathy. © The European Society of Cardiology 2015.

Anxious distress in depressed outpatients: Prevalence, comorbidity, and incremental validity.

PubMed

Rosellini, Anthony J; Bourgeois, Michelle L; Correa, Jeannette; Tung, Esther S; Goncharenko, Svetlana; Brown, Timothy A

2018-05-08

The goals of this study were to estimate the prevalence of the DSM-5 anxious distress specifier (AD) among depressed outpatients, to examine associations of AD with comorbid diagnoses, and to test the incremental validity of AD over comorbidity in predicting functional impairment and severity of anxiety and depression symptoms. The sample was 237 outpatients diagnosed with major depressive disorder (MDD) or persistent depressive disorder (PDD), with and without AD, using the Anxiety and Related Disorders Interview Schedule for DSM-5. Outpatients also completed self-report questionnaires assessing functional impairment and anxiety, stress, and depression symptom severity. Two-by-two contingency tables were used to examine the associations of AD with comorbidity. Two-thirds (66.2%) of outpatients were assigned AD, with similar rates among those with MDD and PDD. Outpatients with AD were significantly more likely than those without AD to have a comorbid GAD diagnosis (OR = 2.47). Hierarchical multiple regressions were used to test the incremental validity of AD in predicting functional impairment and symptom outcomes beyond comorbid disorders. Controlling for comorbid disorders, AD was significantly associated with more severe functional impairment, autonomic arousal, stress, panic, generalized anxiety, and depression. The strongest incremental association were observed between AD and autonomic arousal (f 2  = 0.12-0.18) and generalized anxiety (f 2  = 0.17). These findings add to a growing literature that AD is common among outpatients and associated with important clinical outcomes, suggesting that AD should be routinely assessed in patients with mood disorders. Copyright © 2018 Elsevier Ltd. All rights reserved.

A Comprehensive Functional Analysis of NTRK1 Missense Mutations Causing Hereditary Sensory and Autonomic Neuropathy Type IV (HSAN IV).

PubMed

Shaikh, Samiha S; Chen, Ya-Chun; Halsall, Sally-Anne; Nahorski, Michael S; Omoto, Kiyoyuki; Young, Gareth T; Phelan, Anne; Woods, Christopher Geoffrey

2017-01-01

Hereditary sensory and autonomic neuropathy type IV (HSAN IV) is an autosomal recessive disorder characterized by a complete lack of pain perception and anhidrosis. Here, we studied a cohort of seven patients with HSAN IV and describe a comprehensive functional analysis of seven novel NTRK1 missense mutations, c.1550G >A, c.1565G >A, c.1970T >C, c.2096T >C, c.2254T >A, c.2288G >C, and c.2311C >T, corresponding to p.G517E, p.G522E, p.L657P, p.I699T, p.C752S, p.C763S, and p.R771C, all of which were predicted pathogenic by in silico analysis. The results allowed us to assess the pathogenicity of each mutation and to gain novel insights into tropomyosin receptor kinase A (TRKA) downstream signaling. Each mutation was systematically analyzed for TRKA glycosylation states, intracellular and cell membrane expression patterns, nerve growth factor stimulated TRKA autophosphorylation, TRKA-Y496 phosphorylation, PLCγ activity, and neurite outgrowth. We showed a diverse range of functional effects: one mutation appeared fully functional, another had partial activity in all assays, one mutation affected only the PLCγ pathway and four mutations were proved null in all assays. Thus, we conclude that complete abolition of TRKA kinase activity is not the only pathogenic mechanism underlying HSAN IV. By corollary, the assessment of the clinical pathogenicity of HSAN IV mutations is more complex than initially predicted and requires a multifaceted approach. © 2016 WILEY PERIODICALS, INC.

Cardiac mechanics and heart rate variability in patients with systemic sclerosis: the association that we should not miss.

PubMed

Zlatanovic, Maja; Tadic, Marijana; Celic, Vera; Ivanovic, Branislava; Stevanovic, Ana; Damjanov, Nemanja

2017-01-01

We aimed to determine left ventricular (LV) and right ventricular (RV) structure, function and mechanics, as well as heart rate variability (HRV), and their relationship, in patients with systemic sclerosis (SSc). The study included 41 SSc patients and 30 age-matched healthy volunteers. All the patients underwent clinical examination, serological tests, pulmonary function testing, 24-h Holter monitoring and complete two-dimensional echocardiography including strain analysis. The parameters of LV structure (interventricular septum thickness and LV mass index) and RV structure (RV wall thickness) were significantly higher in SSc patients. LV and RV diastolic function (estimated by mitral and tricuspid E/e' ratio) was significantly impaired in SSc group comparing with the healthy controls. LV and RV longitudinal function was significantly deteriorated in SSc patients. LV circumferential strain was also significantly lower in SSc group, whereas LV radial strain was similar between the observed groups. All parameters of time and frequency domain of HRV were decreased in SSc patients. LV and RV cardiac remodeling parameters, particularly diastolic function and longitudinal strain, were associated with HRV indices without regard to the main demographic or the clinical and echocardiographic characteristics. Rodnan Skin Score was also independently associated with biventricular cardiac remodeling in SSc patients. LV and RV structure, function and mechanics, as well as autonomic nervous function, were significantly impaired in SSc patients. There is the significant association between biventricular cardiac remodeling and autonomic function in these patients, which could be useful for their everyday clinical assessment.

Teaching Cardiac Autonomic Function Dynamics Employing the Valsalva (Valsalva-Weber) Maneuver

ERIC Educational Resources Information Center

Junqueira, Luiz Fernando, Jr.

2008-01-01

In this report, a brief history of the Valsalva (Valsalva-Weber) maneuver is outlined, followed by an explanation on the use of this approach for the evaluation of cardiac autonomic function based on underlying heart rate changes. The most important methodological and interpretative aspects of the Valsalva-Weber maneuver are critically updated,…

Vagal-immune interactions involved in cholinergic anti-inflammatory pathway.

PubMed

Zila, I; Mokra, D; Kopincova, J; Kolomaznik, M; Javorka, M; Calkovska, A

2017-09-22

Inflammation and other immune responses are involved in the variety of diseases and disorders. The acute response to endotoxemia includes activation of innate immune mechanisms as well as changes in autonomic nervous activity. The autonomic nervous system and the inflammatory response are intimately linked and sympathetic and vagal nerves are thought to have anti-inflammation functions. The basic functional circuit between vagus nerve and inflammatory response was identified and the neuroimmunomodulation loop was called cholinergic anti-inflammatory pathway. Unique function of vagus nerve in the anti-inflammatory reflex arc was found in many experimental and pre-clinical studies. They brought evidence on the cholinergic signaling interacting with systemic and local inflammation, particularly suppressing immune cells function. Pharmacological/electrical modulation of vagal activity suppressed TNF-alpha and other proinflammatory cytokines production and had beneficial therapeutic effects. Many questions related to mapping, linking and targeting of vagal-immune interactions have been elucidated and brought understanding of its basic physiology and provided the initial support for development of Tracey´s inflammatory reflex. This review summarizes and critically assesses the current knowledge defining cholinergic anti-inflammatory pathway with main focus on studies employing an experimental approach and emphasizes the potential of modulation of vagally-mediated anti-inflammatory pathway in the treatment strategies.

Validation of the Early Functional Abilities scale: An assessment of four dimensions in early recovery after traumatic brain injury.

PubMed

Poulsen, Ingrid; Kreiner, Svend; Engberg, Aase W

2018-02-13

The Early Functional Abilities scale assesses the restoration of brain function after brain injury, based on 4 dimensions. The primary objective of this study was to evaluate the validity, objectivity, reliability and measurement precision of the Early Functional Abilities scale by Rasch model item analysis. A secondary objective was to examine the relationship between the Early Functional Abilities scale and the Functional Independence Measurement™, in order to establish the criterion validity of the Early Functional Abilities scale and to compare the sensitivity of measurements using the 2 instruments. The Rasch analysis was based on the assessment of 408 adult patients at admission to sub-acute rehabilitation in Copenhagen, Denmark after traumatic brain injury. The Early Functional Abilities scale provides valid and objective measurement of vegetative (autonomic), facio-oral, sensorimotor and communicative/cognitive functions. Removal of one item from the sensorimotor scale confirmed unidimensionality for each of the 4 subscales, but not for the entire scale. The Early Functional Abilities subscales are sensitive to differences between patients in ranges in which the Functional Independence Measurement™ has a floor effect. The Early Functional Abilities scale assesses the early recovery of important aspects of brain function after traumatic brain injury, but is not unidimensional. We recommend removal of the "standing" item and calculation of summary subscales for the separate dimensions.

Heart rate variability in normal and pathological sleep.

PubMed

Tobaldini, Eleonora; Nobili, Lino; Strada, Silvia; Casali, Karina R; Braghiroli, Alberto; Montano, Nicola

2013-10-16

Sleep is a physiological process involving different biological systems, from molecular to organ level; its integrity is essential for maintaining health and homeostasis in human beings. Although in the past sleep has been considered a state of quiet, experimental and clinical evidences suggest a noteworthy activation of different biological systems during sleep. A key role is played by the autonomic nervous system (ANS), whose modulation regulates cardiovascular functions during sleep onset and different sleep stages. Therefore, an interest on the evaluation of autonomic cardiovascular control in health and disease is growing by means of linear and non-linear heart rate variability (HRV) analyses. The application of classical tools for ANS analysis, such as HRV during physiological sleep, showed that the rapid eye movement (REM) stage is characterized by a likely sympathetic predominance associated with a vagal withdrawal, while the opposite trend is observed during non-REM sleep. More recently, the use of non-linear tools, such as entropy-derived indices, have provided new insight on the cardiac autonomic regulation, revealing for instance changes in the cardiovascular complexity during REM sleep, supporting the hypothesis of a reduced capability of the cardiovascular system to deal with stress challenges. Interestingly, different HRV tools have been applied to characterize autonomic cardiac control in different pathological conditions, from neurological sleep disorders to sleep disordered breathing (SDB). In summary, linear and non-linear analysis of HRV are reliable approaches to assess changes of autonomic cardiac modulation during sleep both in health and diseases. The use of these tools could provide important information of clinical and prognostic relevance.

Information for Successful Interaction with Autonomous Systems

NASA Technical Reports Server (NTRS)

Malin, Jane T.; Johnson, Kathy A.

2003-01-01

Interaction in heterogeneous mission operations teams is not well matched to classical models of coordination with autonomous systems. We describe methods of loose coordination and information management in mission operations. We describe an information agent and information management tool suite for managing information from many sources, including autonomous agents. We present an integrated model of levels of complexity of agent and human behavior, which shows types of information processing and points of potential error in agent activities. We discuss the types of information needed for diagnosing problems and planning interactions with an autonomous system. We discuss types of coordination for which designs are needed for autonomous system functions.

Executive Cognitive Functioning and Cardiovascular Autonomic Regulation in a Population-Based Sample of Working Adults.

PubMed

Stenfors, Cecilia U D; Hanson, Linda M; Theorell, Töres; Osika, Walter S

2016-01-01

Objective: Executive cognitive functioning is essential in private and working life and is sensitive to stress and aging. Cardiovascular (CV) health factors are related to cognitive decline and dementia, but there is relatively few studies of the role of CV autonomic regulation, a key component in stress responses and risk factor for cardiovascular disease (CVD), and executive processes. An emerging pattern of results from previous studies suggest that different executive processes may be differentially associated with CV autonomic regulation. The aim was thus to study the associations between multiple measures of CV autonomic regulation and measures of different executive cognitive processes. Method: Participants were 119 healthy working adults (79% women), from the Swedish Longitudinal Occupational Survey of Health. Electrocardiogram was sampled for analysis of heart rate variability (HRV) measures, including the Standard Deviation of NN, here heart beats (SDNN), root of the mean squares of successive differences (RMSSD), high frequency (HF) power band from spectral analyses, and QT variability index (QTVI), a measure of myocardial repolarization patterns. Executive cognitive functioning was measured by seven neuropsychological tests. The relationships between CV autonomic regulation measures and executive cognitive measures were tested with bivariate and partial correlational analyses, controlling for demographic variables, and mental health symptoms. Results: Higher SDNN and RMSSD and lower QTVI were significantly associated with better performance on cognitive tests tapping inhibition, updating, shifting, and psychomotor speed. After adjustments for demographic factors however (age being the greatest confounder), only QTVI was clearly associated with these executive tests. No such associations were seen for working memory capacity . Conclusion: Poorer CV autonomic regulation in terms of lower SDNN and RMSSD and higher QTVI was associated with poorer executive cognitive functioning in terms of inhibition, shifting, updating, and speed in healthy working adults. Age could largely explain the associations between the executive measures and SDNN and RMSSD, while associations with QTVI remained. QTVI may be a useful measure of autonomic regulation and promising as an early indicator of risk among otherwise healthy adults, compared to traditional HRV measures, as associations between QTVI and executive functioning was not affected by age.

Executive Cognitive Functioning and Cardiovascular Autonomic Regulation in a Population-Based Sample of Working Adults

PubMed Central

Stenfors, Cecilia U. D.; Hanson, Linda M.; Theorell, Töres; Osika, Walter S.

2016-01-01

Objective: Executive cognitive functioning is essential in private and working life and is sensitive to stress and aging. Cardiovascular (CV) health factors are related to cognitive decline and dementia, but there is relatively few studies of the role of CV autonomic regulation, a key component in stress responses and risk factor for cardiovascular disease (CVD), and executive processes. An emerging pattern of results from previous studies suggest that different executive processes may be differentially associated with CV autonomic regulation. The aim was thus to study the associations between multiple measures of CV autonomic regulation and measures of different executive cognitive processes. Method: Participants were 119 healthy working adults (79% women), from the Swedish Longitudinal Occupational Survey of Health. Electrocardiogram was sampled for analysis of heart rate variability (HRV) measures, including the Standard Deviation of NN, here heart beats (SDNN), root of the mean squares of successive differences (RMSSD), high frequency (HF) power band from spectral analyses, and QT variability index (QTVI), a measure of myocardial repolarization patterns. Executive cognitive functioning was measured by seven neuropsychological tests. The relationships between CV autonomic regulation measures and executive cognitive measures were tested with bivariate and partial correlational analyses, controlling for demographic variables, and mental health symptoms. Results: Higher SDNN and RMSSD and lower QTVI were significantly associated with better performance on cognitive tests tapping inhibition, updating, shifting, and psychomotor speed. After adjustments for demographic factors however (age being the greatest confounder), only QTVI was clearly associated with these executive tests. No such associations were seen for working memory capacity. Conclusion: Poorer CV autonomic regulation in terms of lower SDNN and RMSSD and higher QTVI was associated with poorer executive cognitive functioning in terms of inhibition, shifting, updating, and speed in healthy working adults. Age could largely explain the associations between the executive measures and SDNN and RMSSD, while associations with QTVI remained. QTVI may be a useful measure of autonomic regulation and promising as an early indicator of risk among otherwise healthy adults, compared to traditional HRV measures, as associations between QTVI and executive functioning was not affected by age. PMID:27761124

Autonomic nervous functions in fetal type Minamata disease patients: assessment of heart rate variability.

PubMed

Oka, Tomoko; Matsukura, Makoto; Okamoto, Miwako; Harada, Noriaki; Kitano, Takao; Miike, Teruhisa; Futatsuka, Makoto

2002-12-01

In order to assess the cardiovascular autonomic nervous functions in patients with fetal type Minamata disease (FMD), we investigated blood pressure (BP), and conducted time and frequency domain analysis of heart rate variability (HRV). Subjects were 9 patients in Meisuien recognized as FMD, and 13 healthy age matched control subjects. HRV and BP were assessed after subjects rested in a supine position for 10 minutes. Electrocardiographic (ECG) data were collected for 3 minutes during natural breathing. Time domain analysis (the average of R-R intervals [Mean RR], standard deviation of R-R intervals [SD RR], coefficient of variation [CV]), and frequency domain analysis by fast Fourier transformation (FFT) (power of low frequency [LF] and high frequency [HF] component, expressed in normalized units[nu]) were then conducted. In the time domain analysis, the mean RR of the FMD group was significantly lower than that of the control group. Neither SD RR nor CV showed significant differences between the two groups, but both tended to be lower in the FMD group. In the frequency domain analysis, the HF component of the FMD group was significantly lower than that of the control group. Pulse pressure (PP) was significantly lower in the FMD subjects. These findings suggest that parasympathetic nervous dysfunction might exist in FMD patients, who were exposed to high doses of methylmercury (MeHg) during the prenatal period. Decrease of PP might be due to degenerative changes of blood vessels driven by exposure to high doses of MeHg.

System control of an autonomous planetary mobile spacecraft

NASA Technical Reports Server (NTRS)

Dias, William C.; Zimmerman, Barbara A.

1990-01-01

The goal is to suggest the scheduling and control functions necessary for accomplishing mission objectives of a fairly autonomous interplanetary mobile spacecraft, while maximizing reliability. Goals are to provide an extensible, reliable system conservative in its use of on-board resources, while getting full value from subsystem autonomy, and avoiding the lure of ground micromanagement. A functional layout consisting of four basic elements is proposed: GROUND and SYSTEM EXECUTIVE system functions and RESOURCE CONTROL and ACTIVITY MANAGER subsystem functions. The system executive includes six subfunctions: SYSTEM MANAGER, SYSTEM FAULT PROTECTION, PLANNER, SCHEDULE ADAPTER, EVENT MONITOR and RESOURCE MONITOR. The full configuration is needed for autonomous operation on Moon or Mars, whereas a reduced version without the planning, schedule adaption and event monitoring functions could be appropriate for lower-autonomy use on the Moon. An implementation concept is suggested which is conservative in use of system resources and consists of modules combined with a network communications fabric. A language concept termed a scheduling calculus for rapidly performing essential on-board schedule adaption functions is introduced.

Caffeine delays autonomic recovery following acute exercise.

PubMed

Bunsawat, Kanokwan; White, Daniel W; Kappus, Rebecca M; Baynard, Tracy

2015-11-01

Impaired autonomic recovery of heart rate (HR) following exercise is associated with an increased risk of sudden death. Caffeine, a potent stimulator of catecholamine release, has been shown to augment blood pressure (BP) and sympathetic nerve activity; however, whether caffeine alters autonomic function after a bout of exercise bout remains unclear. In a randomized, crossover study, 18 healthy individuals (26 ± 1 years; 23.9 ± 0.8 kg·m(-2)) ingested caffeine (400 mg) or placebo pills, followed by a maximal treadmill test to exhaustion. Autonomic function and ventricular depolarization/repolarization were determined using heart rate variability (HRV) and corrected QT interval (QTc), respectively, at baseline, 5, 15, and 30 minutes post-exercise. Maximal HR (HRmax) was greater with caffeine (192 ± 2 vs. 190 ± 2 beat·min(-1), p < 0.05). During recovery, HR, mean arterial pressure (MAP), and diastolic blood pressure (DBP) remained elevated with caffeine (p < 0.05). Natural log transformation of low-to-high frequency ratio (LnLF/LnHF) of HRV was increased compared with baseline at all time points in both trials (p < 0.05), with less of an increase during 5 and 15 minutes post-exercise in the caffeine trial (p < 0.05). QTc increased from baseline at all time points in both trials, with greater increases in the caffeine trial (p < 0.05). Caffeine ingestion disrupts post-exercise autonomic recovery because of increased sympathetic nerve activity. The prolonged sympathetic recovery time could subsequently hinder baroreflex function during recovery and disrupt the stability of autonomic function, potentiating a pro-arrhythmogenic state in young adults. © The European Society of Cardiology 2014.

"The face of ostracism": The impact of the social categorization on the thermal facial responses of the target and the observer.

PubMed

Paolini, Daniele; Alparone, Francesca R; Cardone, Daniela; van Beest, Ilja; Merla, Arcangelo

2016-01-01

Ostracism has been shown to elicit pain in both the target and the observers. Two experiments investigated the autonomic thermal signature associated with an ostracism experience and assessed whether and how social categorization impacts the autonomic arousal of both the target and the observer. Autonomic response was assessed using thermal infrared imaging, recording facial temperature variation during an online game of ball toss (i.e., Cyberball). Social categorization was manipulated using a minimal group paradigm. The results show a more intense autonomic response during ostracism (vs. inclusion), marked by an increase in facial temperature in the nose and the perioral area. This autonomic response is stronger when individuals are ostracized by ingroup (vs. outgroup) members. Similar pattern of temperature variations emerge when individuals observe an ostracism episode involving ingroup members. Our findings advance the understanding of psycho-physiological mechanisms underlying the ostracism experience and emphasize the impact of social categorization in such mechanisms. Copyright © 2015 Elsevier B.V. All rights reserved.

Heart rate variability regression and risk of sudden unexpected death in epilepsy.

PubMed

Galli, Alessio; Lombardi, Federico

2017-02-01

The exact mechanisms of sudden unexpected death in epilepsy remain elusive, despite there is consensus that SUDEP is associated with severe derangements in the autonomic control to vital functions as breathing and heart rate regulation. Heart rate variability (HRV) has been advocated as biomarker of autonomic control to the heart. Cardiac dysautonomia has been found in diseases where other branches of the autonomous nervous system are damaged, as Parkinson disease and multiple system atrophy. In this perspective, an impaired HRV not only is a risk factor for sudden cardiac death mediated by arrhythmias, but also a potential biomarker for monitoring a progressive decline of the autonomous nervous system. This slope may lead to an acute imbalance of the regulatory pathways of vital functions after seizure and then to SUDEP. Copyright © 2016 Elsevier Ltd. All rights reserved.

Autonomous Cryogenics Loading Operations Simulation Software: Knowledgebase Autonomous Test Engineer

NASA Technical Reports Server (NTRS)

Wehner, Walter S., Jr.

2013-01-01

Working on the ACLO (Autonomous Cryogenics Loading Operations) project I have had the opportunity to add functionality to the physics simulation software known as KATE (Knowledgebase Autonomous Test Engineer), create a new application allowing WYSIWYG (what-you-see-is-what-you-get) creation of KATE schematic files and begin a preliminary design and implementation of a new subsystem that will provide vision services on the IHM (Integrated Health Management) bus. The functionality I added to KATE over the past few months includes a dynamic visual representation of the fluid height in a pipe based on number of gallons of fluid in the pipe and implementing the IHM bus connection within KATE. I also fixed a broken feature in the system called the Browser Display, implemented many bug fixes and made changes to the GUI (Graphical User Interface).

Autonomic dysfunction in muscular dystrophy: a theoretical framework for muscle reflex involvement

PubMed Central

Smith, Scott A.; Downey, Ryan M.; Williamson, Jon W.; Mizuno, Masaki

2014-01-01

Muscular dystrophies are a heterogeneous group of genetically inherited disorders whose most prominent clinical feature is progressive degeneration of skeletal muscle. In several forms of the disease, the function of cardiac muscle is likewise affected. The primary defect in this group of diseases is caused by mutations in myocyte proteins important to cellular structure and/or performance. That being stated, a growing body of evidence suggests that the development of autonomic dysfunction may secondarily contribute to the generation of skeletal and cardio-myopathy in muscular dystrophy. Indeed, abnormalities in the regulation of both sympathetic and parasympathetic nerve activity have been reported in a number of muscular dystrophy variants. However, the mechanisms mediating this autonomic dysfunction remain relatively unknown. An autonomic reflex originating in skeletal muscle, the exercise pressor reflex, is known to contribute significantly to the control of sympathetic and parasympathetic activity when stimulated. Given the skeletal myopathy that develops with muscular dystrophy, it is logical to suggest that the function of this reflex might also be abnormal with the pathogenesis of disease. As such, it may contribute to or exacerbate the autonomic dysfunction that manifests. This possibility along with a basic description of exercise pressor reflex function in health and disease are reviewed. A better understanding of the mechanisms that possibly underlie autonomic dysfunction in muscular dystrophy may not only facilitate further research but could also lead to the identification of new therapeutic targets for the treatment of muscular dystrophy. PMID:24600397

Diverse autonomic regulation of pupillary function and the cardiovascular system during alcohol withdrawal.

PubMed

Jochum, Thomas; Hoyme, Johannes; Schulz, Steffen; Weißenfels, Markus; Voss, Andreas; Bär, Karl-Jürgen

2016-02-01

Previous research indicated the complexity of autonomic dysfunction during acute alcohol withdrawal. This study aimed to investigate the pupillary light reflex as an indicator of midbrain and brainstem regulatory systems in relation to cardiovascular autonomic function. Thirty male patients were included in the study. They were investigated during acute alcohol withdrawal syndrome and 24h later during clomethiazole treatment and compared to healthy controls. Parameters of pupillary light reflex of both eyes as well as heart rate variability, blood pressure variability and baroreflex sensitivity (BRS) were studied. We observed significantly reduced sympathetic (small diameter, e.g., left eye: 5.00 in patients vs. 5.91 mm in controls) and vagal modulation (e.g., prolonged latencies, left eye: 0.28 vs. 0.26 ms) regarding both pupils during acute alcohol withdrawal syndrome. Cardiovascular parameters showed reduced vagal modulation (e.g., b-slope of BRS: 7. 57 vs. 13.59 ms/mm Hg) and mixed results for sympathetic influence. After 24h, autonomic dysfunction improved significantly, both for the pupils (e.g., left diameter: 5.38 mm) and the heart (e.g., b-slope of BRS: 9.34 ms/mm Hg). While parameters obtained from the pupil correlated with cardiac autonomic function (e.g, BRS and left diameter: r=0.564) in healthy controls, no such pattern was observed in patients. Results obtained from the pupil during acute alcohol withdrawal do not simply mirror autonomic dysfunction regarding the heart. Pupillary and cardiovascular changes after 24h indicate state dependencies of the results. The findings are discussed with respect to autonomic mechanisms and potentially involved brain regions. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Quantifying Effects of Pharmacological Blockers of Cardiac Autonomous Control Using Variability Parameters.

PubMed

Miyabara, Renata; Berg, Karsten; Kraemer, Jan F; Baltatu, Ovidiu C; Wessel, Niels; Campos, Luciana A

2017-01-01

Objective: The aim of this study was to identify the most sensitive heart rate and blood pressure variability (HRV and BPV) parameters from a given set of well-known methods for the quantification of cardiovascular autonomic function after several autonomic blockades. Methods: Cardiovascular sympathetic and parasympathetic functions were studied in freely moving rats following peripheral muscarinic (methylatropine), β1-adrenergic (metoprolol), muscarinic + β1-adrenergic, α1-adrenergic (prazosin), and ganglionic (hexamethonium) blockades. Time domain, frequency domain and symbolic dynamics measures for each of HRV and BPV were classified through paired Wilcoxon test for all autonomic drugs separately. In order to select those variables that have a high relevance to, and stable influence on our target measurements (HRV, BPV) we used Fisher's Method to combine the p -value of multiple tests. Results: This analysis led to the following best set of cardiovascular variability parameters: The mean normal beat-to-beat-interval/value (HRV/BPV: meanNN), the coefficient of variation (cvNN = standard deviation over meanNN) and the root mean square differences of successive (RMSSD) of the time domain analysis. In frequency domain analysis the very-low-frequency (VLF) component was selected. From symbolic dynamics Shannon entropy of the word distribution (FWSHANNON) as well as POLVAR3, the non-linear parameter to detect intermittently decreased variability, showed the best ability to discriminate between the different autonomic blockades. Conclusion: Throughout a complex comparative analysis of HRV and BPV measures altered by a set of autonomic drugs, we identified the most sensitive set of informative cardiovascular variability indexes able to pick up the modifications imposed by the autonomic challenges. These indexes may help to increase our understanding of cardiovascular sympathetic and parasympathetic functions in translational studies of experimental diseases.

[The condition of the cardiovascular prevention in Spain].

PubMed

Royo-Bordonada, Miguel Ángel; Lobos, José Maria; Brotons, Carlos; Villar, Fernando; de Pablo, Carmen; Armario, Pedro; Cortés, Olga; Gil Nuñez, Antonio; Lizcano, Angel; de Santiago, Ana; Sans, Susana

2014-01-07

In Spain, where cardiovascular diseases are the leading cause of death, control of their risk factors is low. This study analyzes the implementation of cardiovascular risk (CVR) assessment in clinical practice and the existence of control objectives amongst quality care indicators and professional incentive systems. Between 2010 and 2011, data from each autonomous community were collected, by means of a specific questionnaire concerning prevalence and control of major CVR factors, CVR assessment, and implementation of control objectives amongst quality care indicators and primary care incentive systems. Fifteen out of 17 autonomous communities filled in the questionnaire. CVR was calculated through SCORE in 9 autonomous communities, REGICOR in 3 and Framingham in 3, covering 3.4 to 77.6% of target population. The resulting control of the main CVR factors was low and variable: hypertension (22.7-61.3%), dyslipidemia (11-45.1%), diabetes (18.5-84%) and smoking (20-50.5%). Most autonomous communities did not consider CVR assessment and control amongst quality care indicators or incentive systems, highlighting the lack of initiatives on lifestyles. Variability exists in cardiovascular prevention policies among autonomous communities. It is necessary to implement a common agreed cardiovascular prevention guide, to encourage physicians to implement CVR in electronic clinical history, and to promote CVR assessment and control inclusion amongst quality care indicators and professional incentive systems, focusing on lifestyles management. Copyright © 2012 Elsevier España, S.L. All rights reserved.

Poor self-reported sleep quality and health-related quality of life in patients with chronic fatigue syndrome/myalgic encephalomyelitis.

PubMed

Castro-Marrero, Jesús; Zaragozá, Maria C; González-Garcia, Sergio; Aliste, Luisa; Sáez-Francàs, Naia; Romero, Odile; Ferré, Alex; Fernández de Sevilla, Tomás; Alegre, José

2018-05-16

Non-restorative sleep is a hallmark symptom of chronic fatigue syndrome/myalgic encephalomyelitis. However, little is known about self-reported sleep disturbances in these subjects. This study aimed to assess the self-reported sleep quality and its impact on quality of life in a Spanish community-based chronic fatigue syndrome/myalgic encephalomyelitis cohort. A prospective cross-sectional cohort study was conducted in 1,455 Spanish chronic fatigue syndrome/myalgic encephalomyelitis patients. Sleep quality, fatigue, pain, functional capacity impairment, psychopathological status, anxiety/depression and health-related quality of life were assessed using validated subjective measures. The frequencies of muscular, cognitive, neurological, autonomic and immunological symptom clusters were above 80%. High scores were recorded for pain, fatigue, psychopathological status, anxiety/depression, and low scores for functional capacity and quality of life, all of which correlated significantly (all p < 0.01) with quality of sleep as measured by the Pittsburgh Sleep Quality Index. Multivariate regression analysis showed that after adjusting for age and gender, the pain intensity (odds ratio, 1.11; p <0.05), psychopathological status (odds ratio, 1.85; p < 0.001), fibromyalgia (odds ratio, 1.39; p < 0.05), severe autonomic dysfunction (odds ratio, 1.72; p < 0.05), poor functional capacity (odds ratio, 0.98; p < 0.05) and quality of life (odds ratio, 0.96; both p < 0.001) were significantly associated with poor sleep quality. These findings suggest that this large chronic fatigue syndrome/myalgic encephalomyelitis sample presents poor sleep quality, as assessed by the Pittsburgh Sleep Quality Index, and that this poor sleep quality is associated with many aspects of quality of life. © 2018 European Sleep Research Society.

Autonomic Impairment in Severe Traumatic Brain Injury: A Multimodal Neuromonitoring Study.

PubMed

Sykora, Marek; Czosnyka, Marek; Liu, Xiuyun; Donnelly, Joseph; Nasr, Nathalie; Diedler, Jennifer; Okoroafor, Francois; Hutchinson, Peter; Menon, David; Smielewski, Peter

2016-06-01

Autonomic impairment after acute traumatic brain injury has been associated independently with both increased morbidity and mortality. Links between autonomic impairment and increased intracranial pressure or impaired cerebral autoregulation have been described as well. However, relationships between autonomic impairment, intracranial pressure, impaired cerebral autoregulation, and outcome remain poorly explored. Using continuous measurements of heart rate variability and baroreflex sensitivity we aimed to test whether autonomic markers are associated with functional outcome and mortality independently of intracranial variables. Further, we aimed to evaluate the relationships between autonomic functions, intracranial pressure, and cerebral autoregulation. Retrospective analysis of a prospective database. Neurocritical care unit in a university hospital. Sedated patients with severe traumatic brain injury. Waveforms of intracranial pressure and arterial blood pressure, baseline Glasgow Coma Scale and 6 months Glasgow Outcome Scale were recorded. Baroreflex sensitivity was assessed every 10 seconds using a modified cross-correlational method. Frequency domain analyses of heart rate variability were performed automatically every 10 seconds from a moving 300 seconds of the monitoring time window. Mean values of baroreflex sensitivity, heart rate variability, intracranial pressure, arterial blood pressure, cerebral perfusion pressure, and impaired cerebral autoregulation over the entire monitoring period were calculated for each patient. Two hundred and sixty-two patients with a median age of 36 years entered the analysis. The median admission Glasgow Coma Scale was 6, the median Glasgow Outcome Scale was 3, and the mortality at 6 months was 23%. Baroreflex sensitivity (adjusted odds ratio, 0.9; p = 0.02) and relative power of a high frequency band of heart rate variability (adjusted odds ratio, 1.05; p < 0.001) were individually associated with mortality, independently of age, admission Glasgow Coma Scale, intracranial pressure, pressure reactivity index, or cerebral perfusion pressure. Baroreflex sensitivity showed no correlation with intracranial pressure or cerebral perfusion pressure; the correlation with pressure reactivity index was strong in older patients (age, > 60 yr). The relative power of high frequency correlated significantly with intracranial pressure and cerebral perfusion pressure, but not with pressure reactivity index. The relative power of low frequency correlated significantly with pressure reactivity index. Autonomic impairment, as measured by heart rate variability and baroreflex sensitivity, is significantly associated with increased mortality after traumatic brain injury. These effects, though partially interlinked, seem to be independent of age, trauma severity, intracranial pressure, or autoregulatory status, and thus represent a discrete phenomenon in the pathophysiology of traumatic brain injury. Continuous measurements of heart rate variability and baroreflex sensitivity in the neuromonitoring setting of severe traumatic brain injury may carry novel pathophysiological and predictive information.

Effect of Pranayama on stress and cardiovascular autonomic function.

PubMed

Bhimani, N T; Kulkarni, N B; Kowale, A; Salvi, S

2011-01-01

The stress either physical or mental, leads to cardiovascular morbidity. Newly admitted medical students are likely to be exposed to various stresses like change of environment, demanding medical education and different teaching protocol in a medical college. Pranayama is known since ancient times to relieve stress and stabilize autonomic function of the body. Therefore it was decided to study effect of Pranayama on stress and cardiovascular autonomic function. The subjects were first M.B.B.S students and the sample size was 59 consisting of 27 males and 32 females. The group of students thus selected was briefed about the study. After the orientation session, informed written consent was taken, stress questionnaire was put and the autonomic function tests were done. This was followed by practice of Pranayama for 2 months, 1 hour/day for 5 days/week and again stress questionnaire was put and the autonomic function tests were performed on the study group. The above tests were done before and after the practice of Pranayama. The results obtained were analyzed using SPSS software. The stress level has reduced after 2 months of practicing various pranayama as evident by decrease in total stress score which is highly significant. VLF and LF in n.u have reduced significantly after practice of pranayama signifying reduction in sympathetic drive to heart. HF in n.u has increased significantly after practice of pranayama for 2 months showing the increase in parasympathetic output to the heart. LF/ HF ratio reduced significantly after 2 months of practice of pranayama indicating a better sympatho vagal balance with resting balance tilting toward better parasympathetic control.

Autonomic nervous system correlates in movement observation and motor imagery

PubMed Central

Collet, C.; Di Rienzo, F.; El Hoyek, N.; Guillot, A.

2013-01-01

The purpose of the current article is to provide a comprehensive overview of the literature offering a better understanding of the autonomic nervous system (ANS) correlates in motor imagery (MI) and movement observation. These are two high brain functions involving sensori-motor coupling, mediated by memory systems. How observing or mentally rehearsing a movement affect ANS activity has not been extensively investigated. The links between cognitive functions and ANS responses are not so obvious. We will first describe the organization of the ANS whose main purposes are controlling vital functions by maintaining the homeostasis of the organism and providing adaptive responses when changes occur either in the external or internal milieu. We will then review how scientific knowledge evolved, thus integrating recent findings related to ANS functioning, and show how these are linked to mental functions. In turn, we will describe how movement observation or MI may elicit physiological responses at the peripheral level of the autonomic effectors, thus eliciting autonomic correlates to cognitive activity. Key features of this paper are to draw a step-by step progression from the understanding of ANS physiology to its relationships with high mental processes such as movement observation or MI. We will further provide evidence that mental processes are co-programmed both at the somatic and autonomic levels of the central nervous system (CNS). We will thus detail how peripheral physiological responses may be analyzed to provide objective evidence that MI is actually performed. The main perspective is thus to consider that, during movement observation and MI, ANS activity is an objective witness of mental processes. PMID:23908623

The nature of the autonomic dysfunction in multiple system atrophy

NASA Technical Reports Server (NTRS)

Parikh, Samir M.; Diedrich, Andre; Biaggioni, Italo; Robertson, David

2002-01-01

The concept that multiple system atrophy (MSA, Shy-Drager syndrome) is a disorder of the autonomic nervous system is several decades old. While there has been renewed interest in the movement disorder associated with MSA, two recent consensus statements confirm the centrality of the autonomic disorder to the diagnosis. Here, we reexamine the autonomic pathophysiology in MSA. Whereas MSA is often thought of as "autonomic failure", new evidence indicates substantial persistence of functioning sympathetic and parasympathetic nerves even in clinically advanced disease. These findings help explain some of the previously poorly understood features of MSA. Recognition that MSA entails persistent, constitutive autonomic tone requires a significant revision of our concepts of its diagnosis and therapy. We will review recent evidence bearing on autonomic tone in MSA and discuss their therapeutic implications, particularly in terms of the possible development of a bionic baroreflex for better control of blood pressure.

Autonomic symptoms following Zika virus infection.

PubMed

Rodríguez, Yhojan; Rojas, Manuel; Ramírez-Santana, Carolina; Acosta-Ampudia, Yeny; Monsalve, Diana M; Anaya, Juan-Manuel

2018-04-01

To determine if autonomic symptoms are associated with previous Zika virus infection. Case-control study including 35 patients with Zika virus infection without evidence of neurological disease and 105 controls. Symptoms of autonomic dysfunction were assessed with the composite autonomic symptom scale 31 (COMPASS-31). Patients with previous Zika virus infection had significantly higher COMPASS-31 score than controls regardless of age and sex (p = 0.007). The main drivers for the higher scores where orthostatic intolerance (p = 0.003), secretomotor (p = 0.04) and bladder symptoms (p < 0.001). Zika virus infection is associated with autonomic dysfunction. The mechanisms remain to be elucidated.

Deep brain stimulation does not change neurovascular coupling in non-motor visual cortex: an autonomic and visual evoked blood flow velocity response study.

PubMed

Azevedo, Elsa; Santos, Rosa; Freitas, João; Rosas, Maria-José; Gago, Miguel; Garrett, Carolina; Rosengarten, Bernhard

2010-11-01

In Parkinson's disease (PD) subthalamic nucleus deep brain stimulation (STN-DBS) improves motor function. Also an effect on the neurovascular coupling in motor cortex was reported due to a parallel activation of a subthalamic vasodilator area (SVA). To address this issue further we analysed neurovascular coupling in a non-motor area. Twenty PD patients selected for bilateral STN-DBS were investigated with functional transcranial Doppler (f-TCD) before and after surgery. Hemodynamic responses to visual stimulation were registered in left posterior cerebral artery (PCA) and analysed with a control-system approach (parameters gain, rate time, attenuation and natural frequency). To exclude autonomic effects of STN-DBS, we also addressed spectrum analysis of heart rate and of systolic arterial blood pressure variability, and baroreceptor gain. Findings in the PD group were compared with healthy age-matched controls. PD patients showed no neurovascular coupling changes in PCA territory, compared to controls, and STN-DBS changed neither blood flow regulatory parameters nor autonomic function. Improvement of vasoregulation in some motor cortical areas after STN-DBS might be related to an improved neuronal functional rather than indicating an effect on the neurovascular coupling or autonomic function. Copyright © 2010 Elsevier Ltd. All rights reserved.

Cardiac and peripheral adjustments induced by early exercise training intervention were associated with autonomic improvement in infarcted rats: role in functional capacity and mortality.

PubMed

Jorge, Luciana; Rodrigues, Bruno; Rosa, Kaleizu Teodoro; Malfitano, Christiane; Loureiro, Tatiana Carolina Alba; Medeiros, Alessandra; Curi, Rui; Brum, Patricia Chakur; Lacchini, Silvia; Montano, Nicola; De Angelis, Kátia; Irigoyen, Maria-Cláudia

2011-04-01

To test the effects of early exercise training (ET) on left ventricular (LV) and autonomic functions, haemodynamics, tissues blood flows (BFs), maximal oxygen consumption (VO(2) max), and mortality after myocardial infarction (MI) in rats. Male Wistar rats were divided into: control (C), sedentary-infarcted (SI), and trained-infarcted (TI). One week after MI, TI group underwent an ET protocol (90 days, 50-70% VO(2) max). Left ventricular function was evaluated non-invasively and invasively. Baroreflex sensitivity, heart rate variability, and pulse interval were measured. Cardiac output (CO) and regional BFs were determined using coloured microspheres. Infarcted area was reduced in TI (19 ± 6%) compared with SI (34 ± 5%) after ET. Exercise training improved the LV and autonomic functions, the CO and regional BF changes induced by MI, as well as increased SERCA2 expression and mRNA vascular endothelial growth factor levels. These changes brought about by ET resulted in mortality rate reduction in the TI (13%) group compared with the SI (54%) group. Early aerobic ET reduced cardiac and peripheral dysfunctions and preserved cardiovascular autonomic control after MI in trained rats. Consequently, these ET-induced changes resulted in improved functional capacity and survival after MI.

Effect of 48 h Fasting on Autonomic Function, Brain Activity, Cognition, and Mood in Amateur Weight Lifters.

PubMed

Solianik, Rima; Sujeta, Artūras; Terentjevienė, Asta; Skurvydas, Albertas

2016-01-01

Objectives. The acute fasting-induced cardiovascular autonomic response and its effect on cognition and mood remain debatable. Thus, the main purpose of this study was to estimate the effect of a 48 h, zero-calorie diet on autonomic function, brain activity, cognition, and mood in amateur weight lifters. Methods. Nine participants completed a 48 h, zero-calorie diet program. Cardiovascular autonomic function, resting frontal brain activity, cognitive performance, and mood were evaluated before and after fasting. Results. Fasting decreased ( p < 0.05) weight, heart rate, and systolic blood pressure, whereas no changes were evident regarding any of the measured heart rate variability indices. Fasting decreased ( p < 0.05) the concentration of oxygenated hemoglobin and improved ( p < 0.05) mental flexibility and shifting set, whereas no changes were observed in working memory, visuospatial discrimination, and spatial orientation ability. Fasting also increased ( p < 0.05) anger, whereas other mood states were not affected by it. Conclusions. 48 h fasting resulted in higher parasympathetic activity and decreased resting frontal brain activity, increased anger, and improved prefrontal-cortex-related cognitive functions, such as mental flexibility and set shifting, in amateur weight lifters. In contrast, hippocampus-related cognitive functions were not affected by it.

Effect of 48 h Fasting on Autonomic Function, Brain Activity, Cognition, and Mood in Amateur Weight Lifters

PubMed Central

Skurvydas, Albertas

2016-01-01

Objectives. The acute fasting-induced cardiovascular autonomic response and its effect on cognition and mood remain debatable. Thus, the main purpose of this study was to estimate the effect of a 48 h, zero-calorie diet on autonomic function, brain activity, cognition, and mood in amateur weight lifters. Methods. Nine participants completed a 48 h, zero-calorie diet program. Cardiovascular autonomic function, resting frontal brain activity, cognitive performance, and mood were evaluated before and after fasting. Results. Fasting decreased (p < 0.05) weight, heart rate, and systolic blood pressure, whereas no changes were evident regarding any of the measured heart rate variability indices. Fasting decreased (p < 0.05) the concentration of oxygenated hemoglobin and improved (p < 0.05) mental flexibility and shifting set, whereas no changes were observed in working memory, visuospatial discrimination, and spatial orientation ability. Fasting also increased (p < 0.05) anger, whereas other mood states were not affected by it. Conclusions. 48 h fasting resulted in higher parasympathetic activity and decreased resting frontal brain activity, increased anger, and improved prefrontal-cortex-related cognitive functions, such as mental flexibility and set shifting, in amateur weight lifters. In contrast, hippocampus-related cognitive functions were not affected by it. PMID:28025637

Emotional Responses to Odors in Children with High-Functioning Autism: Autonomic Arousal, Facial Behavior and Self-Report

ERIC Educational Resources Information Center

Legisa, Jasna; Messinger, Daniel S.; Kermol, Enzo; Marlier, Luc

2013-01-01

Although emotional functioning is impaired in children with autism, it is unclear if this impairment is due to difficulties with facial expression, autonomic responsiveness, or the verbal description of emotional states. To shed light on this issue, we examined responses to pleasant and unpleasant odors in eight children (8-14 years) with…

Association between obesity and heart rate variability indices: an intuition toward cardiac autonomic alteration - a risk of CVD.

PubMed

Yadav, Ram Lochan; Yadav, Prakash Kumar; Yadav, Laxmi Kumari; Agrawal, Kopila; Sah, Santosh Kumar; Islam, Md Nazrul

2017-01-01

Obese people have a higher prevalence of cardiovascular disease, which is supposed to be due to autonomic dysfunction and/or metabolic disorder. The alterations in cardiac autonomic functions bring out the changes in the heart rate variability (HRV) indicators, an assessing tool for cardiac autonomic conditions. To compare the cardiac autonomic activity between obese and normal weight adults and find out the highest association between the indices of HRV and obesity. The study was conducted in 30 adult obese persons (body mass index [BMI] >30 kg/m 2 ) and 29 healthy normal weight controls (BMI 18-24 kg/m 2 ). Short-term HRV variables were assessed using standard protocol. Data were compared between groups using Mann-Whitney U test. Obesity indices such as waist circumference, hip circumference, waist-hip ratio (WHR), and BMI were measured and calculated, and they were correlated with HRV indices using Spearman's correlation analysis. In the obese group, there was a significant increase in the mean heart rate, whereas the HRV parasympathetic indicators were less (eg, root mean square of differences of successive RR intervals [28.75 {16.72-38.35} vs 41.55 {30.6-56.75} ms, p =0.018], number of RR intervals that differ by >50 ms, that is, NN50 [15.5 {2-39} vs 83.5 {32.75-116.25}, p =0.010], etc) and the sympathetic indicator low frequency (LF)/high frequency (HF) ratio (1.2 [0.65-2.20] vs 0.79 [0.5-1.02], p =0.045) was more than that of the normal weight group. Spearman's correlation between HRV and obesity indices showed significant positive correlation of WHR with LF in normalized unit ( r =0.478, p <0.01) and LF/HF ratio ( r =0.479, p <0.01), whereas it had significant negative correlation with high frequency power ms 2 ( r =-0.374, p <0.05) and HF in normalized unit ( r =-0.478, p <0.01). There was a nonsignificant correlation of BMI with HRV variables in obese individuals. Increased WHR, by far an indicator of visceral adiposity, was strongly associated with reduced cardiac parasympathetic and increased sympathetic activity in obese individuals defined by BMI. However, BMI itself has a weak relationship with HRV cardiac autonomic markers. Thus, even with a slight increase in WHR in an individual, there could be a greater risk of cardiovascular morbidity and mortality brought about by cardiac autonomic alterations.

Could autonomic system assessment be helpful in disorders of consciousness diagnosis? A neurophysiological study.

PubMed

Leo, Antonino; Naro, Antonino; Cannavò, Antonio; Pisani, Laura Rosa; Bruno, Rocco; Salviera, Carlo; Bramanti, Placido; Calabrò, Rocco Salvatore

2016-08-01

Although patients with chronic disorders of consciousness (DOC), including unresponsive wakefulness syndrome (UWS) and minimally conscious state (MCS), show a limited repertoire of awareness signs, owing to a large-scale cortico-thalamo-cortical functional disconnectivity, an activation of some cortical areas in response to relevant stimuli has been described by means of electrophysiological and functional neuroimaging approaches. In addition, cognitive processes associated with autonomic nervous system (ANS) responses elicited by nociceptive stimuli have been identified in some DOC patients. In an attempt to identify ANS functionality markers that could be useful in differentiating UWS and MCS individuals, we measured the amplitude, latency and γ-band power (γPOW) of ultra-late laser-evoked potentials (CLEPs) and skin reflex (SR), which both express some aspects of cognitive processes related to ANS functionality, besides other ANS parameters either during a 24(hh)-polygraphy or following a solid-state laser repetitive nociceptive stimulation. MCS showed physiological modification of vital signs (O2 saturation, hearth rate, hearth rate variability) throughout the night and a preservation of SR-γPOW, whereas UWS did not show significant variations. Following repetitive nociceptive stimulation, MCS patients had a significant increase in CLEP-γPOW, O2 saturation, hearth rate, and hearth rate variability, whereas UWS individuals did not show any significant change (but two patients, who reached high Coma Recovery Scale-Revised scores). Hence, our work suggests that a wide-spectrum electrophysiological evaluation of ANS functionality may support DOC differential diagnosis. Interestingly, the two above-mentioned UWS patients showed MCS-like vital sign modifications and electrophysiological pain responsiveness. It is therefore hypothesizable that our approach could be helpful in identifying residual aware autonomic system-related cognitive processes even in some UWS patients. Such issue draws the attention to either DOC clinical diagnosis or adequate pain treatment in DOC patients.

The reliability of a single protocol to determine endothelial, microvascular and autonomic functions in adolescents.

PubMed

Bond, Bert; Williams, Craig A; Barker, Alan R

2017-11-01

Impairments in macrovascular, microvascular and autonomic function are present in asymptomatic youths with clustered cardiovascular disease risk factors. This study determines the within-day reliability and between-day reliability of a single protocol to non-invasively assess these outcomes in adolescents. Forty 12- to 15-year-old adolescents (20 boys) visited the laboratory in a fasted state on two occasions, approximately 1 week apart. One hour after a standardized cereal breakfast, macrovascular function was determined via flow-mediated dilation (FMD). Heart rate variability (root mean square of successive R-R intervals; RMSSD) was determined from the ECG-gated ultrasound images acquired during the FMD protocol prior to cuff occlusion. Microvascular function was simultaneously quantified as the peak (PRH) and total (TRH) hyperaemic response to occlusion in the cutaneous circulation of the forearm via laser Doppler imaging. To address within-day reliability, a subset of twenty adolescents (10 boys) repeated these measures 90 min afterwards on one occasion. The within-day typical error and between-day typical error expressed as a coefficient of variation of these outcomes are as follows: ratio-scaled FMD, 5·1% and 10·6%; allometrically scaled FMD, 4·4% and 9·4%; PRH, 11% and 13·3%; TRH, 29·9% and 23·1%; and RMSSD, 17·6% and 17·6%. The within- and between-day test-retest correlation coefficients for these outcomes were all significant (r > 0·54 for all). Macrovascular, microvascular and autonomic functions can be simultaneously and non-invasively determined in adolescents using a single protocol with an appropriate degree of reproducibility. Determining these outcomes may provide greater understanding of the progression of cardiovascular disease and aid early intervention. © 2016 Scandinavian Society of Clinical Physiology and Nuclear Medicine. Published by John Wiley & Sons Ltd.

Measurement of Coronary-Prone Behavior and Autonomic Reactivity.

DTIC Science & Technology

1981-05-01

function or emotionality, suggests a three-factor model: a general autonomic e:tivity factor identical with anxiety and two other autonomic activity...alerting response may be an example of Cattell’s general anxiety factor. Other studies have focused on similarities of physiological responses across...approach. Zuckerman et al. (81) examined the relationships amon: anxiety , depression, hostility, GSR, heart rate, and breathing during a cold pressor

Memory dysfunction and autonomic neuropathy in non-insulin-dependent (type 2) diabetic patients.

PubMed

Zaslavsky, L M; Gross, J L; Chaves, M L; Machado, R

1995-11-01

Considering the nervous system as a unit, it might be expected that diabetic patients with autonomic neuropathy could have a central abnormality expressed as cognitive dysfunction. To determine whether autonomic neuropathy is independently associated with cognitive dysfunction, we studied a cross-section of 20 non-insulin-dependent diabetic patients with autonomic neuropathy (14 males and six females; age (mean) = 60 + or - 1 years); 29 non-insulin-dependent diabetic patients without autonomic neuropathy (14 males and 15 females; age = 59 + or - 1 years) and 34 non-diabetic patients (10 males and 24 females; age = 58 + or - 1 years), matched by age, education and duration of disease. Cognitive function was evaluated by tests of immediate, recent and remote memory: verbal (digit span; word span) and visual (recognition of towers and famous faces). Diabetic patients with autonomic neuropathy scored (median) lower in visual memory tests than diabetic patients without autonomic neuropathy and controls (towers immediate = 5 versus 7 and 6; towers recent = 4 versus 6 and 6; faces = 16 versus 18 and 18; respectively; Kruskal-Wallis; P < 0.05). There was no difference in verbal memory performance (Kruskal-Wallis; P > 0.05). Entering age, education, duration of disease and fasting plasma glucose in a stepwise multiple regression, the performance in these tests remained associated with autonomic neuropathy (towers immediate, P = 0.0054, partial r2 = 0.166; towers recent, P = 0.0076, partial r2 = 0.163). Scores in visual tests correlated negatively with the number of abnormal cardiovascular tests (faces, r = -0.25; towers recent, r = -0.24; Spearman; P < 0.05). Decreased visual cognitive function in non-insulin-dependent diabetic patients is associated with the presence and degree of autonomic neuropathy.

Space station automation study. Volume 1: Executive summary. Autonomous systems and assembly

NASA Technical Reports Server (NTRS)

1984-01-01

The purpose of the Space Station Automation Study (SSAS) was to develop informed technical guidance for NASA personnel in the use of autonomy and autonomous systems to implement space station functions.

Development of autonomous grasping and navigating robot

NASA Astrophysics Data System (ADS)

Kudoh, Hiroyuki; Fujimoto, Keisuke; Nakayama, Yasuichi

2015-01-01

The ability to find and grasp target items in an unknown environment is important for working robots. We developed an autonomous navigating and grasping robot. The operations are locating a requested item, moving to where the item is placed, finding the item on a shelf or table, and picking the item up from the shelf or the table. To achieve these operations, we designed the robot with three functions: an autonomous navigating function that generates a map and a route in an unknown environment, an item position recognizing function, and a grasping function. We tested this robot in an unknown environment. It achieved a series of operations: moving to a destination, recognizing the positions of items on a shelf, picking up an item, placing it on a cart with its hand, and returning to the starting location. The results of this experiment show the applicability of reducing the workforce with robots.

Evidence for vestibular regulation of autonomic functions in a mouse genetic model

NASA Technical Reports Server (NTRS)

Murakami, Dean M.; Erkman, Linda; Hermanson, Ola; Rosenfeld, Michael G.; Fuller, Charles A.

2002-01-01

Physiological responses to changes in the gravitational field and body position, as well as symptoms of patients with anxiety-related disorders, have indicated an interrelationship between vestibular function and stress responses. However, the relative significance of cochlear and vestibular information in autonomic regulation remains unresolved because of the difficulties in distinguishing the relative contributions of other proprioceptive and interoceptive inputs, including vagal and somatic information. To investigate the role of cochlear and vestibular function in central and physiological responses, we have examined the effects of increased gravity in wild-type mice and mice lacking the POU homeodomain transcription factor Brn-3.1 (Brn-3bPou4f3). The only known phenotype of the Brn-3.1(-/-) mouse is related to hearing and balance functions, owing to the failure of cochlear and vestibular hair cells to differentiate properly. Here, we show that normal physiological responses to increased gravity (2G exposure), such as a dramatic drop in body temperature and concomitant circadian adjustment, were completely absent in Brn-3.1(-/-) mice. In line with the lack of autonomic responses, the massive increase in neuronal activity after 2G exposure normally detected in wild-type mice was virtually abolished in Brn-3.1(-/-) mice. Our results suggest that cochlear and vestibular hair cells are the primary regulators of autonomic responses to altered gravity and provide genetic evidence that these cells are sufficient to alter neural activity in regions involved in autonomic and neuroendocrine control.

An autonomous, automated and mobile device to concurrently assess several cognitive functions in group-living non-human primates.

PubMed

Fizet, Jonas; Rimele, Adam; Pebayle, Thierry; Cassel, Jean-Christophe; Kelche, Christian; Meunier, Hélène

2017-11-01

Research methods in cognitive neuroscience using non-human primates have undergone notable changes over the last decades. Recently, several research groups have described freely accessible devices equipped with a touchscreen interface. Two characteristics of such systems are of particular interest: some apparatuses include automated identification of subjects, while others are mobile. Here, we designed, tested and validated an experimental system that, for the first time, combine automatization and mobility. Moreover, our system allows autonomous learning and testing of cognitive performance in group-living subjects, including follow-up assessments. The mobile apparatus is designed to be available 24h a day, 7days a week, in a typical confined primate breeding and housing facility. Here we present as proof of concept, the results of two pilot studies. We report that rhesus macaques (Macaca mulatta) learned the tasks rapidly and achieved high-level of stable performance. Approaches of this kind should be developed for future pharmacological and biomedical studies in non-human primates. Copyright © 2017 Elsevier Inc. All rights reserved.

High-frequency autonomic modulation: a new model for analysis of autonomic cardiac control.

PubMed

Champéroux, Pascal; Fesler, Pierre; Judé, Sebastien; Richard, Serge; Le Guennec, Jean-Yves; Thireau, Jérôme

2018-05-03

Increase in high-frequency beat-to-beat heart rate oscillations by torsadogenic hERG blockers appears to be associated with signs of parasympathetic and sympathetic co-activation which cannot be assessed directly using classic methods of heart rate variability analysis. The present work aimed to find a translational model that would allow this particular state of the autonomic control of heart rate to be assessed. High-frequency heart rate and heart period oscillations were analysed within discrete 10 s intervals in a cohort of 200 healthy human subjects. Results were compared to data collected in non-human primates and beagle dogs during pharmacological challenges and torsadogenic hERG blockers exposure, in 127 genotyped LQT1 patients on/off β-blocker treatment and in subgroups of smoking and non-smoking subjects. Three states of autonomic modulation, S1 (parasympathetic predominance) to S3 (reciprocal parasympathetic withdrawal/sympathetic activation), were differentiated to build a new model of heart rate variability referred to as high-frequency autonomic modulation. The S2 state corresponded to a specific state during which both parasympathetic and sympathetic systems were coexisting or co-activated. S2 oscillations were proportionally increased by torsadogenic hERG-blocking drugs, whereas smoking caused an increase in S3 oscillations. The combined analysis of the magnitude of high-frequency heart rate and high-frequency heart period oscillations allows a refined assessment of heart rate autonomic modulation applicable to long-term ECG recordings and offers new approaches to assessment of the risk of sudden death both in terms of underlying mechanisms and sensitivity. © 2018 The Authors. British Journal of Pharmacology published by John Wiley & Sons Ltd on behalf of British Pharmacological Society.

Large-scale assessment of benthic communities across multiple marine protected areas using an autonomous underwater vehicle.

PubMed

Ferrari, Renata; Marzinelli, Ezequiel M; Ayroza, Camila Rezende; Jordan, Alan; Figueira, Will F; Byrne, Maria; Malcolm, Hamish A; Williams, Stefan B; Steinberg, Peter D

2018-01-01

Marine protected areas (MPAs) are designed to reduce threats to biodiversity and ecosystem functioning from anthropogenic activities. Assessment of MPAs effectiveness requires synchronous sampling of protected and non-protected areas at multiple spatial and temporal scales. We used an autonomous underwater vehicle to map benthic communities in replicate 'no-take' and 'general-use' (fishing allowed) zones within three MPAs along 7o of latitude. We recorded 92 taxa and 38 morpho-groups across three large MPAs. We found that important habitat-forming biota (e.g. massive sponges) were more prevalent and abundant in no-take zones, while short ephemeral algae were more abundant in general-use zones, suggesting potential short-term effects of zoning (5-10 years). Yet, short-term effects of zoning were not detected at the community level (community structure or composition), while community structure varied significantly among MPAs. We conclude that by allowing rapid, simultaneous assessments at multiple spatial scales, autonomous underwater vehicles are useful to document changes in marine communities and identify adequate scales to manage them. This study advanced knowledge of marine benthic communities and their conservation in three ways. First, we quantified benthic biodiversity and abundance, generating the first baseline of these benthic communities against which the effectiveness of three large MPAs can be assessed. Second, we identified the taxonomic resolution necessary to assess both short and long-term effects of MPAs, concluding that coarse taxonomic resolution is sufficient given that analyses of community structure at different taxonomic levels were generally consistent. Yet, observed differences were taxa-specific and may have not been evident using our broader taxonomic classifications, a classification of mid to high taxonomic resolution may be necessary to determine zoning effects on key taxa. Third, we provide an example of statistical analyses and sampling design that once temporal sampling is incorporated will be useful to detect changes of marine benthic communities across multiple spatial and temporal scales.

Large-scale assessment of benthic communities across multiple marine protected areas using an autonomous underwater vehicle

PubMed Central

Ayroza, Camila Rezende; Jordan, Alan; Figueira, Will F.; Byrne, Maria; Malcolm, Hamish A.; Williams, Stefan B.; Steinberg, Peter D.

2018-01-01

Marine protected areas (MPAs) are designed to reduce threats to biodiversity and ecosystem functioning from anthropogenic activities. Assessment of MPAs effectiveness requires synchronous sampling of protected and non-protected areas at multiple spatial and temporal scales. We used an autonomous underwater vehicle to map benthic communities in replicate ‘no-take’ and ‘general-use’ (fishing allowed) zones within three MPAs along 7o of latitude. We recorded 92 taxa and 38 morpho-groups across three large MPAs. We found that important habitat-forming biota (e.g. massive sponges) were more prevalent and abundant in no-take zones, while short ephemeral algae were more abundant in general-use zones, suggesting potential short-term effects of zoning (5–10 years). Yet, short-term effects of zoning were not detected at the community level (community structure or composition), while community structure varied significantly among MPAs. We conclude that by allowing rapid, simultaneous assessments at multiple spatial scales, autonomous underwater vehicles are useful to document changes in marine communities and identify adequate scales to manage them. This study advanced knowledge of marine benthic communities and their conservation in three ways. First, we quantified benthic biodiversity and abundance, generating the first baseline of these benthic communities against which the effectiveness of three large MPAs can be assessed. Second, we identified the taxonomic resolution necessary to assess both short and long-term effects of MPAs, concluding that coarse taxonomic resolution is sufficient given that analyses of community structure at different taxonomic levels were generally consistent. Yet, observed differences were taxa-specific and may have not been evident using our broader taxonomic classifications, a classification of mid to high taxonomic resolution may be necessary to determine zoning effects on key taxa. Third, we provide an example of statistical analyses and sampling design that once temporal sampling is incorporated will be useful to detect changes of marine benthic communities across multiple spatial and temporal scales. PMID:29547656

Enhancing physical function in HIV-infected older adults: A randomized controlled clinical trial.

PubMed

Shah, Krupa N; Majeed, Zahraa; Yoruk, Yilmaz B; Yang, Hongmei; Hilton, Tiffany N; McMahon, James M; Hall, William J; Walck, Donna; Luque, Amneris E; Ryan, Richard M

2016-06-01

HIV-infected older adults (HOA) are at risk of functional decline. Interventions promoting physical activity that can attenuate functional decline and are easily translated into the HOA community are of high priority. We conducted a randomized, controlled clinical trial to evaluate whether a physical activity counseling intervention based on self-determination theory (SDT) improves physical function, autonomous motivation, depression and the quality of life (QOL) in HOA. In total, 67 community-dwelling HOA with mild-to-moderate functional limitations were randomized to 1 of 2 groups: a physical activity counseling group or the usual care control group. We used SDT to guide the development of the experimental intervention. Outcome measures that were collected at baseline and final study visits included a battery of physical function tests, levels of physical activity, autonomous motivation, depression, and QOL. The study participants were similar in their demographic and clinical characteristics in both the treatment and control groups. Overall physical performance, gait speed, measures of endurance and strength, and levels of physical activity improved in the treatment group compared to the control group (p < .05). Measures of autonomous regulation such as identified regulation, and measures of depression and QOL improved significantly in the treatment group compared with the control group (p < .05). Across the groups, improvement in intrinsic regulation and QOL correlated with an improvement in physical function (p < .05). Our findings suggest that a physical activity counseling program grounded in SDT can improve physical function, autonomous motivation, depression, and QOL in HOA with functional limitations. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

Self-reported post-exertional fatigue in Gulf War veterans: roles of autonomic testing

PubMed Central

Li, Mian; Xu, Changqing; Yao, Wenguo; Mahan, Clare M.; Kang, Han K.; Sandbrink, Friedhelm; Zhai, Ping; Karasik, Pamela A.

2014-01-01

To determine if objective evidence of autonomic dysfunction exists from a group of Gulf War veterans with self-reported post-exertional fatigue, we evaluated 16 Gulf War ill veterans and 12 Gulf War controls. Participants of the ill group had self- reported, unexplained chronic post-exertional fatigue and the illness symptoms had persisted for years until the current clinical study. The controls had no self-reported post-exertional fatigue either at the time of initial survey nor at the time of the current study. We intended to identify clinical autonomic disorders using autonomic and neurophysiologic testing in the clinical context. We compared the autonomic measures between the 2 groups on cardiovascular function at both baseline and head-up tilt, and sudomotor function. We identified 1 participant with orthostatic hypotension, 1 posture orthostatic tachycardia syndrome, 2 distal small fiber neuropathy, and 1 length dependent distal neuropathy affecting both large and small fiber in the ill group; whereas none of above definable diagnoses was noted in the controls. The ill group had a significantly higher baseline heart rate compared to controls. Compound autonomic scoring scale showed a significant higher score (95% CI of mean: 1.72–2.67) among ill group compared to controls (0.58–1.59). We conclude that objective autonomic testing is necessary for the evaluation of self-reported, unexplained post-exertional fatigue among some Gulf War veterans with multi-symptom illnesses. Our observation that ill veterans with self-reported post-exertional fatigue had objective autonomic measures that were worse than controls warrants validation in a larger clinical series. PMID:24431987

Development of autonomous eating mechanism for biomimetic robots

NASA Astrophysics Data System (ADS)

Jeong, Kil-Woong; Cho, Ik-Jin; Lee, Yun-Jung

2005-12-01

Most of the recently developed robots are human friendly robots which imitate animals or humans such as entertainment robot, bio-mimetic robot and humanoid robot. Interest for these robots are being increased because the social trend is focused on health, welfare, and graying. Autonomous eating functionality is most unique and inherent behavior of pets and animals. Most of entertainment robots and pet robots make use of internal-type battery. Entertainment robots and pet robots with internal-type battery are not able to operate during charging the battery. Therefore, if a robot has an autonomous function for eating battery as its feeds, the robot is not only able to operate during recharging energy but also become more human friendly like pets. Here, a new autonomous eating mechanism was introduced for a biomimetic robot, called ELIRO-II(Eating LIzard RObot version 2). The ELIRO-II is able to find a food (a small battery), eat and evacuate by itself. This work describe sub-parts of the developed mechanism such as head-part, mouth-part, and stomach-part. In addition, control system of autonomous eating mechanism is described.

Autonomic neuropathy in an alcoholic population.

PubMed

Barter, F; Tanner, A R

1987-12-01

Autonomic nervous system integrity has been assessed in 30 alcoholic subjects and 30 age-sex matched controls using five simple tests of cardiovascular responses. There was evidence of parasympathetic neuropathy alone in five of the alcoholic subjects (16%) and of combined parasympathetic and sympathetic neuropathy in an additional six (20%). None of the controls showed any abnormality. Within the alcoholic group, those with autonomic neuropathy were older, were more likely to be female and to have established alcoholic liver disease. Symptoms were a poor guide to the presence or absence of autonomic neuropathy.

Development of Autonomous Aerobraking - Phase 2

NASA Technical Reports Server (NTRS)

Murri, Daniel G.

2013-01-01

Phase 1 of the Development of Autonomous Aerobraking (AA) Assessment investigated the technical capability of transferring the processes of aerobraking maneuver (ABM) decision-making (currently performed on the ground by an extensive workforce and communicated to the spacecraft via the deep space network) to an efficient flight software algorithm onboard the spacecraft. This document describes Phase 2 of this study, which was a 12-month effort to improve and rigorously test the AA Development Software developed in Phase 1. Aerobraking maneuver; Autonomous Aerobraking; Autonomous Aerobraking Development Software; Deep Space Network; NASA Engineering and Safety Center

[Does autonomic diabetic neuropathy influence microcirculation reactivity in adolescents with diabetes type 1?].

PubMed

Urban, Mirosława; Peczyńska, Jadwiga; Kowalewski, Marek; Głowińska-Olszewska, Barbara

2007-01-01

Microcirculation is known to be disturbed in many organs of diabetic patients. Retinopathy, nephropathy and neuropathy might be considered as the cause of the functional and morphological changes at the level of microcirculation. The aim of the study was to assess by means of dynamic capillaroscopy the influence of autonomic diabetic nephropathy (CAN) in adolescents with type 1 diabetes mellitus on capillary blood flow (CBV) in skin microcirculation. The study group consisted of 18 patients with type 1 diabetes mellitus (mean age 15+/-2 years). In 9 of them the diagnosis of CAN was made on the basis of Ewing tests. The control group consisted of 10 healthy persons aged 15+/-1.5 years. CBV was measured in capillars of the nailfold of the fourth finger during rest and after 2 minutes of arterial occlusion (the occlusion pressure - above 20 mmHg systolic blood pressure - was obtained by the occlusion of brachial artery using sphygnomanometer cuff). The resting CBV did not differ between patients with CAN, without CAN and healthy controls (0.39+/-0.06, 0.41+0.05 i 0.42+/-0.07). The values of the peak CBV significantly differ between the examined groups (CAN: 0.75+0.1; without CAN: 0.86+/-0.11; control group: 0.98+/-0.09, p<0.01). The obtained results indicate that the presence of the autonomic diabetic neuropathy significantly influences the regulatory function of microcirculation, which may predispose to occurrence of different late diabetic complications.

Predictors of treatment use among foster mothers in an attachment-based intervention program.

PubMed

Bick, Johanna; Dozier, Mary; Moore, Shannon

2012-01-01

The current study examined predictors of treatment use among 56 foster mothers who participated in an attachment-based intervention program for foster infants. Foster mothers' levels of treatment use were coded at early, middle, and late phases of the intervention program. Foster mothers' states of mind with regard to attachment predicted their understanding of the intervention session concepts. Specifically, autonomous foster mothers showed higher levels of understanding at the start of the intervention program, when compared with non-autonomous foster mothers. State of mind with regard to attachment also predicted foster mothers' levels of reflective functioning during the intervention sessions. Autonomous foster mothers showed higher levels of reflective functioning at early, middle, and late stages of the intervention program, when compared with non-autonomous foster mothers. The relevance of these findings for both treatment effectiveness and treatment delivery is discussed.

Acute stress alters autonomic modulation during sleep in women approaching menopause.

PubMed

de Zambotti, Massimiliano; Sugarbaker, David; Trinder, John; Colrain, Ian M; Baker, Fiona C

2016-04-01

Hot flashes, hormones, and psychosocial factors contribute to insomnia risk in the context of the menopausal transition. Stress is a well-recognized factor implicated in the pathophysiology of insomnia; however the impact of stress on sleep and sleep-related processes in perimenopausal women remains largely unknown. We investigated the effect of an acute experimental stress (impending Trier Social Stress Task in the morning) on pre-sleep measures of cortisol and autonomic arousal in perimenopausal women with and without insomnia that developed in the context of the menopausal transition. In addition, we assessed the macro- and micro-structure of sleep and autonomic functioning during sleep. Following adaptation to the laboratory, twenty two women with (age: 50.4 ± 3.2 years) and eighteen women without (age: 48.5 ± 2.3 years) insomnia had two randomized in-lab overnight recordings: baseline and stress nights. Anticipation of the task resulted in higher pre-sleep salivary cortisol levels and perceived tension, faster heart rate and lower vagal activity, based on heart rate variability measures, in both groups of women. The effect of the stress manipulation on the autonomic nervous system extended into the first 4 h of the night in both groups. However, vagal tone recovered 4-6 h into the stress night in controls but not in the insomnia group. Sleep macrostructure was largely unaltered by the stress, apart from a delayed latency to REM sleep in both groups. Quantitative analysis of non-rapid eye movement sleep microstructure revealed greater electroencephalographic (EEG) power in the beta1 range (15-≤23 Hz), reflecting greater EEG arousal during sleep, on the stress night compared to baseline, in the insomnia group. Hot flash frequency remained similar on both nights for both groups. These results show that pre-sleep stress impacts autonomic nervous system functioning before and during sleep in perimenopausal women with and without insomnia. Findings also indicate that women with insomnia had increased EEG arousal and lacked recovery in vagal activity across the stress night suggesting a greater sensitivity to stress in this group. Copyright © 2015 Elsevier Ltd. All rights reserved.

Preserved functional autonomic phenotype in adult mice overexpressing moderate levels of human alpha-synuclein in oligodendrocytes.

PubMed

Tank, Jens; da Costa-Goncalves, Andrey C; Kamer, Ilona; Qadri, Fatimunnisa; Ubhi, Kiren; Rockenstein, Edward; Diedrich, André; Masliah, Eliezer; Gross, Volkmar; Jordan, Jens

2014-11-01

Mice overexpressing human alpha-synuclein in oligodendrocytes (MBP1-α-syn) recapitulate some key functional and neuropathological features of multiple system atrophy (MSA). Whether or not these mice develop severe autonomic failure, which is a key feature of human MSA, remains unknown. We explored cardiovascular autonomic regulation using long-term blood pressure (BP) radiotelemetry and pharmacological testing. We instrumented 12 MBP1-α-syn mice and 11 wild-type mice aged 9 months for radiotelemetry. Animals were tested with atropine, metoprolol, clonidine, and trimethaphan at 9 and 12 months age. We applied spectral and cross-spectral analysis to assess heart rate (HR) and BP variability. At 9 months of age daytime BP (transgenic: 101 ± 2 vs. wild type: 99 ± 2 mmHg) and HR (497 ± 11 vs. 505 ± 16 beats/min) were similar. Circadian BP and HR rhythms were maintained. Nighttime BP (109 ± 2 vs. 108 ± 2 mmHg) and HR (575 ± 15 vs. 569 ± 14 beats/min), mean arterial BP responses to trimethaphan (-21 ± 8 vs. -10 ± 5 mmHg, P = 0.240) and to clonidine (-8 ± 3 vs. -5 ± 2 mmHg, P = 0.314) were similar. HR responses to atropine (+159 ± 24 vs. +146 ± 22 beats/min), and to clonidine (-188 ± 21 vs. -163 ± 33 beats/min) did not differ between strains. Baroreflex sensitivity (4 ± 1 vs. 4 ± 1 msec/mmHg) and HR variability (total power, 84 ± 17 vs. 65 ± 21 msec²) were similar under resting conditions and during pharmacological testing. Repeated measurements at 12 months of age provided similar results. In mice, moderate overexpression of human alpha-synuclein in oligodendrocytes is not sufficient to induce overt autonomic failure. Additional mechanisms may be required to express the autonomic failure phenotype including higher levels of expression or more advanced age. © 2014 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on behalf of the American Physiological Society and The Physiological Society.

Dynamic multisensor fusion for mobile robot navigation in an indoor environment

NASA Astrophysics Data System (ADS)

Jin, Taeseok; Lee, Jang-Myung; Luk, Bing L.; Tso, Shiu K.

2001-10-01

In this study, as the preliminary step for developing a multi-purpose Autonomous robust carrier mobile robot to transport trolleys or heavy goods and serve as robotic nursing assistant in hospital wards. The aim of this paper is to present the use of multi-sensor data fusion such as sonar, CCD camera dn IR sensor for map-building mobile robot to navigate, and presents an experimental mobile robot designed to operate autonomously within both indoor and outdoor environments. Smart sensory systems are crucial for successful autonomous systems. We will give an explanation for the robot system architecture designed and implemented in this study and a short review of existing techniques, since there exist several recent thorough books and review paper on this paper. Instead we will focus on the main results with relevance to the intelligent service robot project at the Centre of Intelligent Design, Automation & Manufacturing (CIDAM). We will conclude by discussing some possible future extensions of the project. It is first dealt with the general principle of the navigation and guidance architecture, then the detailed functions recognizing environments updated, obstacle detection and motion assessment, with the first results form the simulations run.

An Optimized, Data Distribution Service-Based Solution for Reliable Data Exchange Among Autonomous Underwater Vehicles

PubMed Central

Bilbao, Sonia; Martínez, Belén; Frasheri, Mirgita; Cürüklü, Baran

2017-01-01

Major challenges are presented when managing a large number of heterogeneous vehicles that have to communicate underwater in order to complete a global mission in a cooperative manner. In this kind of application domain, sending data through the environment presents issues that surpass the ones found in other overwater, distributed, cyber-physical systems (i.e., low bandwidth, unreliable transport medium, data representation and hardware high heterogeneity). This manuscript presents a Publish/Subscribe-based semantic middleware solution for unreliable scenarios and vehicle interoperability across cooperative and heterogeneous autonomous vehicles. The middleware relies on different iterations of the Data Distribution Service (DDS) software standard and their combined work between autonomous maritime vehicles and a control entity. It also uses several components with different functionalities deemed as mandatory for a semantic middleware architecture oriented to maritime operations (device and service registration, context awareness, access to the application layer) where other technologies are also interweaved with middleware (wireless communications, acoustic networks). Implementation details and test results, both in a laboratory and a deployment scenario, have been provided as a way to assess the quality of the system and its satisfactory performance. PMID:28783049

An Optimized, Data Distribution Service-Based Solution for Reliable Data Exchange Among Autonomous Underwater Vehicles.

PubMed

Rodríguez-Molina, Jesús; Bilbao, Sonia; Martínez, Belén; Frasheri, Mirgita; Cürüklü, Baran

2017-08-05

Major challenges are presented when managing a large number of heterogeneous vehicles that have to communicate underwater in order to complete a global mission in a cooperative manner. In this kind of application domain, sending data through the environment presents issues that surpass the ones found in other overwater, distributed, cyber-physical systems (i.e., low bandwidth, unreliable transport medium, data representation and hardware high heterogeneity). This manuscript presents a Publish/Subscribe-based semantic middleware solution for unreliable scenarios and vehicle interoperability across cooperative and heterogeneous autonomous vehicles. The middleware relies on different iterations of the Data Distribution Service (DDS) software standard and their combined work between autonomous maritime vehicles and a control entity. It also uses several components with different functionalities deemed as mandatory for a semantic middleware architecture oriented to maritime operations (device and service registration, context awareness, access to the application layer) where other technologies are also interweaved with middleware (wireless communications, acoustic networks). Implementation details and test results, both in a laboratory and a deployment scenario, have been provided as a way to assess the quality of the system and its satisfactory performance.

Preliminary study of a millimeter wave FMCW InSAR for UAS indoor navigation.

PubMed

Scannapieco, Antonio F; Renga, Alfredo; Moccia, Antonio

2015-01-22

Small autonomous unmanned aerial systems (UAS) could be used for indoor inspection in emergency missions, such as damage assessment or the search for survivors in dangerous environments, e.g., power plants, underground railways, mines and industrial warehouses. Two basic functions are required to carry out these tasks, that is autonomous GPS-denied navigation with obstacle detection and high-resolution 3Dmapping with moving target detection. State-of-the-art sensors for UAS are very sensitive to environmental conditions and often fail in the case of poor visibility caused by dust, fog, smoke, flames or other factors that are met as nominal mission scenarios when operating indoors. This paper is a preliminary study concerning an innovative radar sensor based on the interferometric Synthetic Aperture Radar (SAR) principle, which has the potential to satisfy stringent requirements set by indoor autonomous operation. An architectural solution based on a frequency-modulated continuous wave (FMCW) scheme is proposed after a detailed analysis of existing compact and lightweight SAR. A preliminary system design is obtained, and the main imaging peculiarities of the novel sensor are discussed, demonstrating that high-resolution, high-quality observation of an assigned control volume can be achieved.

Changes in autonomic regulation and ventricular repolarization induced by subclinical hyperthyroidism.

PubMed

Galetta, F; Franzoni, F; Fallahi, P; Tocchini, L; Graci, F; Gaddeo, C; Rossi, M; Cini, G; Carpi, A; Santoro, G; Antonelli, A

2010-10-01

The aim of the present study was to evaluate the effect of subclinical hyperthyroidism (SHT) on cardiovascular autonomic function and ventricular repolarization. Thirty subjects (25 females; mean age 49.6 ± 9.8 years) with SHT, as judged by reduced TSH serum levels and normal free T4 and T3 serum levels, and 30 age and sex-matched control subjects underwent standard 12-lead ECG, and 24h ambulatory ECG monitoring. The dispersion of the QT interval, an index of inhomogeneity of repolarization, and the heart rate variability (HRV), a measure of cardiac autonomic modulation, were studied. Patients with SHT showed higher QT dispersion (p<0.001) and lower HRV measures (0.01>p<0.001) than controls. In SHT patients, QT dispersion was inversely related to HRV (r=-0.47, p<0.01). The results of the present study demonstrated that SHT is associated with a sympathovagal imbalance, characterized by increased sympathetic activity in the presence of diminished vagal tone, and with an increased inhomogeneity of ventricular recovery times. The assessment of HRV and QT dispersion in patients with SHT may represent a useful tool in monitoring the cardiovascular risk of this condition. Copyright © 2009 Elsevier Masson SAS. All rights reserved.

Preliminary Study of a Millimeter Wave FMCW InSAR for UAS Indoor Navigation

PubMed Central

Scannapieco, Antonio F.; Renga, Alfredo; Moccia, Antonio

2015-01-01

Small autonomous unmanned aerial systems (UAS) could be used for indoor inspection in emergency missions, such as damage assessment or the search for survivors in dangerous environments, e.g., power plants, underground railways, mines and industrial warehouses. Two basic functions are required to carry out these tasks, that is autonomous GPS-denied navigation with obstacle detection and high-resolution 3D mapping with moving target detection. State-of-the-art sensors for UAS are very sensitive to environmental conditions and often fail in the case of poor visibility caused by dust, fog, smoke, flames or other factors that are met as nominal mission scenarios when operating indoors. This paper is a preliminary study concerning an innovative radar sensor based on the interferometric Synthetic Aperture Radar (SAR) principle, which has the potential to satisfy stringent requirements set by indoor autonomous operation. An architectural solution based on a frequency-modulated continuous wave (FMCW) scheme is proposed after a detailed analysis of existing compact and lightweight SAR. A preliminary system design is obtained, and the main imaging peculiarities of the novel sensor are discussed, demonstrating that high-resolution, high-quality observation of an assigned control volume can be achieved. PMID:25621606

Autonomic regulation therapy to enhance myocardial function in heart failure patients: the ANTHEM‐HFpEF study

PubMed Central

DiCarlo, Lorenzo A.; Libbus, Imad; Kumar, H. Uday; Mittal, Sanjay; Premchand, Rajendra K.; Amurthur, Badri; KenKnight, Bruce H.; Ardell, Jeffrey L.

2017-01-01

Abstract Background Approximately half of the patients presenting with new‐onset heart failure (HF) have HF with preserved left ventricular ejection fraction (HFpEF) and HF with mid‐range left ventricular ejection fraction (HFmrEF). These patients have neurohormonal activation like that of HF with reduced ejection fraction; however, beta‐blockers and angiotensin‐converting enzyme inhibitors have not been shown to improve their outcomes, and current treatment for these patients is symptom based and empiric. Sympathoinhibition using parasympathetic stimulation has been shown to improve central and peripheral aspects of the cardiac nervous system, reflex control, induce myocyte cardioprotection, and can lead to regression of left ventricular hypertrophy. Beneficial effects of autonomic regulation therapy (ART) using vagus nerve stimulation (VNS) have also been observed in several animal models of HFpEF, suggesting a potential role for ART in patients with this disease. Methods The Autonomic Neural Regulation Therapy to Enhance Myocardial Function in Patients with Heart Failure and Preserved Ejection Fraction (ANTHEM‐HFpEF) study is designed to evaluate the feasibility, tolerability, and safety of ART using right cervical VNS in patients with chronic, stable HFpEF and HFmrEF. Patients with symptomatic HF and HFpEF or HFmrEF fulfilling the enrolment criteria will receive chronic ART with a subcutaneous VNS system attached to the right cervical vagus nerve. Safety parameters will be continuously monitored, and cardiac function and HF symptoms will be assessed every 3 months during a post‐titration follow‐up period of at least 12 months. Conclusions The ANTHEM‐HFpEF study is likely to provide valuable information intended to expand our understanding of the potential role of ART in patients with chronic symptomatic HFpEF and HFmrEF. PMID:29283224

Maturation of heart rate and blood pressure variability during sleep in term-born infants.

PubMed

Yiallourou, Stephanie R; Sands, Scott A; Walker, Adrian M; Horne, Rosemary S C

2012-02-01

Abnormal blood pressure control is implicated in the sudden infant death syndrome (SIDS). However, no data exist on normal development of blood pressure control during infancy. This study assessed maturation of autonomic control of blood pressure and heart rate during sleep within the first 6 months of life. Term infants (n = 31) were studied longitudinally at 2-4 weeks, 2-3 months, and 5-6 months postnatal age. Infants underwent daytime polysomnography at each age studied. Blood pressure and heart rate were recorded during quiet (QS) and active (AS) sleep in undisturbed baseline and head-up tilt conditions. Autonomic control was assessed using spectral indices of blood pressure and heart rate variability (BPV and HRV) in ranges of low frequency (LF, reflecting sympathetic + parasympathetic activity) and high frequency (HF, parasympathetic activity), total power (LF+HF), and LF/HF ratio (sympathovagal balance). With increasing postnatal age and predominantly during QS, HRV-LF, HRV-HF, and HRV total power increased, while HRV-LF/HF decreased. BPV-LF/HF also decreased with postnatal age. All changes were evident in both baseline and head-up tilt conditions. BPV-LF and BPV total power during tilts were markedly reduced in QS versus AS at each age. In sleeping infants, sympathetic vascular modulation of the circulation decreases with age, while parasympathetic control of heart rate is strengthened. These normative data will aid in the early identification of conditions where autonomic function is impaired, such as in SIDS.

The visceromotor and somatic afferent nerves of the penis.

PubMed

Diallo, Djibril; Zaitouna, Mazen; Alsaid, Bayan; Quillard, Jeanine; Ba, Nathalie; Allodji, Rodrigue Sètchéou; Benoit, Gérard; Bedretdinova, Dina; Bessede, Thomas

2015-05-01

Innervation of the penis supports erectile and sensory functions. This article aims to study the efferent autonomic (visceromotor) and afferent somatic (sensory) nervous systems of the penis and to investigate how these systems relate to vascular pathways. Penises obtained from five adult cadavers were studied via computer-assisted anatomic dissection (CAAD). The number of autonomic and somatic nerve fibers was compared using the Kruskal-Wallis test. Proximally, penile innervation was mainly somatic in the extra-albugineal sector and mainly autonomic in the intracavernosal sector. Distally, both sectors were almost exclusively supplied by somatic nerve fibers, except the intrapenile vascular anastomoses that accompanied both somatic and autonomic (nitrergic) fibers. From this point, the neural immunolabeling within perivascular nerve fibers was mixed (somatic labeling and autonomic labeling). Accessory afferent, extra-albugineal pathways supplied the outer layers of the penis. There is a major change in the functional type of innervation between the proximal and distal parts of the intracavernosal sector of the penis. In addition to the pelvis and the hilum of the penis, the intrapenile neurovascular routes are the third level where the efferent autonomic (visceromotor) and the afferent somatic (sensory) penile nerve fibers are close. Intrapenile neurovascular pathways define a proximal penile segment, which guarantees erectile rigidity, and a sensory distal segment. © 2015 International Society for Sexual Medicine.

Optimized Enhanced Bioremediation Through 4D Geophysical Monitoring and Autonomous Data Collection, Processing and Analysis

DTIC Science & Technology

2014-09-01

High Fructose Corn Syrup Diluted 1 to 10 percent by weight 50 to 500 mg/l Slow Release Whey (fresh/powered) Dissolved (powdered form) or injected...the assessment of remedial progress and functioning. This project also addressed several high priority needs from the Navy Environmental Quality...memory high -performance computing systems. For instance, as of March 2012 the code has been successfully executed on 2 cpu’s for an inversion problem

Guidance and Navigation for Rendezvous and Proximity Operations with a Non-Cooperative Spacecraft at Geosynchronous Orbit

NASA Technical Reports Server (NTRS)

Barbee, Brent William; Carpenter, J. Russell; Heatwole, Scott; Markley, F. Landis; Moreau, Michael; Naasz, Bo J.; VanEepoel, John

2010-01-01

The feasibility and benefits of various spacecraft servicing concepts are currently being assessed, and all require that the servicer spacecraft perform rendezvous, proximity, and capture operations with the target spacecraft to be serviced. Many high-value spacecraft, which would be logical targets for servicing from an economic point of view, are located in geosynchronous orbit, a regime in which autonomous rendezvous and capture operations are not commonplace. Furthermore, existing GEO spacecraft were not designed to be serviced. Most do not have cooperative relative navigation sensors or docking features, and some servicing applications, such as de-orbiting of a non-functional spacecraft, entail rendezvous and capture with a spacecraft that may be non-functional or un-controlled. Several of these challenges have been explored via the design of a notional mission in which a nonfunctional satellite in geosynchronous orbit is captured by a servicer spacecraft and boosted into super-synchronous orbit for safe disposal. A strategy for autonomous rendezvous, proximity operations, and capture is developed, and the Orbit Determination Toolbox (ODTBX) is used to perform a relative navigation simulation to assess the feasibility of performing the rendezvous using a combination of angles-only and range measurements. Additionally, a method for designing efficient orbital rendezvous sequences for multiple target spacecraft is utilized to examine the capabilities of a servicer spacecraft to service multiple targets during the course of a single mission.

Learning Agents for Autonomous Space Asset Management (LAASAM)

NASA Astrophysics Data System (ADS)

Scally, L.; Bonato, M.; Crowder, J.

2011-09-01

Current and future space systems will continue to grow in complexity and capabilities, creating a formidable challenge to monitor, maintain, and utilize these systems and manage their growing network of space and related ground-based assets. Integrated System Health Management (ISHM), and in particular, Condition-Based System Health Management (CBHM), is the ability to manage and maintain a system using dynamic real-time data to prioritize, optimize, maintain, and allocate resources. CBHM entails the maintenance of systems and equipment based on an assessment of current and projected conditions (situational and health related conditions). A complete, modern CBHM system comprises a number of functional capabilities: sensing and data acquisition; signal processing; conditioning and health assessment; diagnostics and prognostics; and decision reasoning. In addition, an intelligent Human System Interface (HSI) is required to provide the user/analyst with relevant context-sensitive information, the system condition, and its effect on overall situational awareness of space (and related) assets. Colorado Engineering, Inc. (CEI) and Raytheon are investigating and designing an Intelligent Information Agent Architecture that will provide a complete range of CBHM and HSI functionality from data collection through recommendations for specific actions. The research leverages CEI’s expertise with provisioning management network architectures and Raytheon’s extensive experience with learning agents to define a system to autonomously manage a complex network of current and future space-based assets to optimize their utilization.

The Effect of Massage Therapy on Autonomic Activity in Critically Ill Children

PubMed Central

Guan, Ling; Yuskiv, Nataliya; Skippen, Peter; Brant, Rollin; Kissoon, Niranjan

2014-01-01

Objectives. Our main objective was to describe the effect of foot and hand (F&H) massage on the autonomic nervous system (ANS) activity in children hospitalized in a pediatric intensive care unit (PICU); the secondary objectives were to assess the relationship between ANS function and the clinical severity and to explore the effects of repeated massage sessions on the ANS. Methods. Design was a descriptive experimental study. Intervention was single or six session(s) of F&H massage. ANS function was assessed through the frequency-domain analysis of heart rate variability. Main metrics included high and low frequency power (HF and LF), HF + LF, and LF/HF ratio. Results. Eighteen children participated in the study. A strong Spearman's correlation (ρ = −0.77) was observed between HF + LF and clinical severity. During massage, the parasympathetic activity (measured by HF) increased significantly from baseline (P = 0.04) with a mean percentage increase of 75% (95% CI: 20%∼130%). LF increased by 56% (95% CI: 20%∼92%) (P = 0.026). Repeated sessions were associated with a persistent effect on HF and LF which peaked at the second session and remained stable thereafter. Conclusions. HF + LF is positively correlated with clinical severity. F&H massage can improve the ANS activity and the effect persists when repeated sessions are offered. PMID:25587344

Decreased cardiac vagal control in drug-naive patients with panic disorder: a case-control study in Taiwan.

PubMed

Chang, Hsin-An; Chang, Chuan-Chia; Tzeng, Nian-Sheng; Kuo, Terry B J; Lu, Ru-Band; Huang, San-Yuan

2013-06-01

Cardiac autonomic dysregulation has been proposed in panic disorder (PD), but the results are mixed. Analyses with larger sample sizes and better methodology are needed. Forty-eight drug-naïve individuals with PD and 202 healthy volunteers were recruited for a case-control analysis. We used the Hamilton Anxiety Rating Scale and the Beck Anxiety Inventory to assess anxiety severity. Cardiac autonomic function was evaluated by measuring heart rate variability (HRV) parameters. Frequency-domain indices of HRV were obtained. The obtained results were evaluated in association with personality traits assessed by the Tridimensional Personality Questionnaire. Patients exhibited reduced mean RR interval (816.94 ± 135.92 versus 873.47 ± 143.36 ms, P = 0.014) and HRV levels (Var 6.37 ± 1.32 versus 7.38 ± 0.95, LF 4.90 ± 1.63 versus5.82 ± 1.11 and HF 4.57 ± 1.53 versus 5.62 ± 1.24 [ln(ms2)], all P < 0.001) as compared to controls, which mainly suggested a reduction in cardiac vagal control in PD. The anxiety severity was negatively correlated with HRV levels (r = -0.29 for Var, r = -0.22 for LF and r = -0.28 for HF, all P < 0.001). The harm avoidance score (which has been suggested to be associated with serotonergic activity) was associated with decreased HRV levels (r = -0.22 for Var, P < 0.01, r = -0.14 for LF, P < 0.05 and r = -0.17 for HF, P < 0.01). This study demonstrates that PD is associated with cardiac autonomic dysregulation, highlighting the importance of assessing HRV in PD patients. Copyright © 2013 Wiley Publishing Asia Pty Ltd.

Differential changes and interactions of autonomic functioning and sleep architecture before and after 50 years of age.

PubMed

Kuo, T B J; Li, Jia-Yi; Kuo, Hsu-Ko; Chern, Chang-Ming; Yang, C C H

2016-02-01

We hypothesize that the time when age-related changes in autonomic functioning and in sleep structure occur are different and that autonomic functioning modulates sleep architecture differently before and after 50 years of age. Sixty-eight healthy subjects (aged 20 to 79 years old, 49 of them women) were enrolled. Correlation analysis revealed that wake after sleep onset, the absolute and relative value of stage 1 (S1; S1%), and relative value of stage 2 (S2) were positively correlated with age; however, sleep efficiency, stage 3 (S3), S3%, and rapid-eye-movement latency (REML) were negatively correlated with age. Significant degenerations of sleep during normal aging were occurred after 50 years of age; however, significant declines of autonomic activity were showed before 50 years of age. Before 50 years of age, vagal function during sleep was negatively correlated with arousal index; however, after 50 years of age, it was positively correlated with S1 and S1%. In addition, sympathetic activity during wake stage was positively related to S2% only after 50 years of age. Our results imply that the age-related changes in autonomic functioning decline promptly as individuals leave the younger part of their adult life span and that age-related changes in sleep slowly develop as individuals enter the older part of their adult life span. Furthermore, while various aspects of sleep architecture are modulated by both the sympathetic and vagal nervous systems during adult life span, the sleep quality is mainly correlated with the sympathetic division after 50 years of age.

ADULTS: A RANDOMIZED CONTROLLED CLINICAL TRIAL

PubMed Central

Shah, Krupa N.; Majeed, Zahraa; Yoruk, Yilmaz B.; Yang, Hongmei; Hilton, Tiffany N.; McMahon, James M.; Hall, William J.; Walck, Donna; Luque, Amneris E.; Ryan, Richard M.

2016-01-01

Objective HIV-infected older adults (HOA) are at risk of functional decline. Interventions promoting physical activity that can attenuate functional decline and are easily translated into the HOA community are of high priority. We conducted a randomized, controlled clinical trial to evaluate whether a physical activity counseling intervention based on self-determination theory (SDT) improves physical function, autonomous motivation, depression and the quality of life (QOL) in HOA. Methods A total of 67 community-dwelling HOA with mild-to-moderate functional limitations were randomized to one of two groups: a physical activity counseling group or the usual care control group. We used SDT to guide the development of the experimental intervention. Outcome measures that were collected at baseline and final study visits included a battery of physical function tests, levels of physical activity, autonomous motivation, depression, and QOL. Results The study participants were similar in their demographic and clinical characteristics in both the treatment and control groups. Overall physical performance, gait speed, measures of endurance and strength, and levels of physical activity improved in the treatment group compared to the control group (p<0.05). Measures of autonomous regulation such as identified regulation, and measures of depression and QOL improved significantly in the treatment group compared to the control group (p<0.05). Across the groups, improvement in intrinsic regulation and QOL correlated with an improvement in physical function (p<0.05). Conclusion Our findings suggest that a physical activity counseling program grounded in SDT can improve physical function, autonomous motivation, depression, and QOL in HOA with functional limitations. PMID:26867045

Associations between xerostomia, histopathological alterations, and autonomic innervation of labial salivary glands in men in late midlife.

PubMed

Sørensen, Christiane Elisabeth; Larsen, Jytte Overgaard; Reibel, Jesper; Lauritzen, Martin; Mortensen, Erik Lykke; Osler, Merete; Pedersen, Anne Marie Lynge

2014-09-01

One aim of the present study was to investigate whether symptoms of oral dryness (xerostomia) during daytime, assessed in a study group of middle-aged male positive and negative outliers in cognition scores, were associated with age-related degenerative changes in human labial salivary glands and with quantitative measures of the glandular autonomic innervation. Another aim was to study the relation between the autonomic innervation and loss of secretory acinar cells in these glands. Labial salivary gland biopsies were taken from the lower lip from 190 men, born in 1953 and members of the Danish Metropolit birth cohort, who were examined for age-related changes in cognitive function and dental health as part of the Copenhagen University Center for Healthy Aging clinical neuroscience project. The glands were routinely processed and semi-quantitatively analyzed for inflammation, acinar atrophy, fibrosis, and adipocyte infiltration. Sections of labial salivary gland tissue were stained with the panneuronal marker PGP 9.5. In a subsample of 51 participants, the autonomic innervation of the glands was analyzed quantitatively by use of stereology. Labial salivary gland tissue samples from 33% of all participants displayed moderate to severe acinar atrophy and fibrosis (31%). Xerostomia was not significantly associated with structural changes of labial salivary glands, but in the subsample it was inversely related to the total nerve length in the glandular connective tissue. Acinar atrophy and fibrosis were negatively correlated with the parenchymal innervation and positively related to diffuse inflammation. The results from the present study indicate that aspects of the autonomic innervation of labial salivary glands may play a role in the occurrence of xerostomia which in the present study group was not significantly associated with degenerative changes in these glands. The findings further indicate that the integrity of labial salivary gland acini is related to the parenchymal autonomic innervation, whereas inflammatory processes may compromise it by alternative mechanisms. Copyright © 2014 Elsevier Inc. All rights reserved.

Cerebro-afferent vessel and pupillary basal diameter variation induced by stomatognathic trigeminal proprioception: a case report.

PubMed

De Cicco, Vincenzo

2012-09-03

A patient affected by asymmetric hemodynamics of cerebro-afferent vessels underwent duplex color scanner investigations in occlusal proprioceptive un- and rebalance conditions. Pupillometric video-oculographic examinations were performed in order to spot connected trigeminal proprioceptive motor patterns able to interfere on sympathetic autonomic activity. The aim of this case report is to verify if involuntary jaw closing during swallowing, executed in unbalance and rebalance myoelectric activity, would be able to modify cerebral hemodynamics. A 56-year-old Caucasian Italian woman affected by asymmetric blood flow of cerebro-afferent vessels underwent an electromyographic investigation of her occlusal muscles in order to assess their occlusal functional balance. The extreme asymmetry of myoelectric activity in dental occlusion evidenced by electromyographic values suggested the rebalancing of the functions of occlusal muscles through concurrent transcutaneous stimulation of the trigeminal nerve supra- and submandibular motor branches. The above-mentioned method allowed the detection of a symmetric craniomandibular muscular relation that can be kept constant through the use of a cusp bite modeled on the inferior dental arch: called orthotic-syntropic bite for its peculiar use of electrostimulation. A few days later, the patient underwent a duplex color scanner investigation and pupillometric video-oculographic examinations in occlusal unbalance and rebalance conditions. A comparative data analysis showed that an unbalanced dental occlusal function may represent an interferential pattern on cerebral hemodynamics velocity and pupillometric evaluations have proved useful both in the analysis of locus coeruleus functional modalities and as a diagnostic tool in the assessment of pathologies involving locus coeruleus and autonomic systems. The inclusion of myoelectric masseter examinations can be useful in patients with asymmetric hemodynamics of cerebro-afferent vessels and dental occlusal proprioceptive rebalance can integrate the complex therapy of patients with increased chronic sympathetic activity.

Small fiber neuropathy in Parkinson's disease: A clinical, pathological and corneal confocal microscopy study.

PubMed

Kass-Iliyya, Lewis; Javed, Saad; Gosal, David; Kobylecki, Christopher; Marshall, Andrew; Petropoulos, Ioannis N; Ponirakis, Georgios; Tavakoli, Mitra; Ferdousi, Maryam; Chaudhuri, Kallol Ray; Jeziorska, Maria; Malik, Rayaz A; Silverdale, Monty A

2015-12-01

Autonomic and somatic denervation is well established in Parkinson's disease (PD). (1) To determine whether corneal confocal microscopy (CCM) can non-invasively demonstrate small nerve fiber damage in PD. (2) To identify relationships between corneal nerve parameters, intraepidermal nerve fiber density (IENFD) and clinical features of PD. Twenty-six PD patients and 26 controls underwent CCM of both eyes. 24/26 PD patients and 10/26 controls underwent skin biopsies from the dorsa of both feet. PD patients underwent assessment of parasympathetic function [deep breathing heart rate variability (DB-HRV)], autonomic symptoms [scale for outcomes in Parkinson's disease - autonomic symptoms (SCOPA-AUT)], motor symptoms [UPDRS-III "ON"] and cumulative Levodopa dose. PD patients had significantly reduced corneal nerve fiber density (CNFD) with increased corneal nerve branch density (CNBD) and corneal nerve fiber length (CNFL) compared to controls. CNBD and CNFL but not CNFD correlated inversely with UPDRS-III and SCOPA-AUT. All CCM parameters correlated strongly with DB-HRV. There was no correlation between CCM parameters and disease duration, cumulative Levodopa dose or pain. IENFD was significantly reduced in PD compared to controls and correlated with CNFD and UPDRS-III. However, unlike CCM measures, IENFD correlated with disease duration and cumulative Levodopa dose but not with autonomic dysfunction. CCM identifies corneal nerve fiber pathology, which correlates with autonomic symptoms, parasympathetic deficits and motor scores in patients with PD. IENFD is also reduced and correlates with CNFD and motor symptoms but not parasympathetic deficits, indicating it detects different aspects of peripheral nerve pathology in PD. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

Towards an Autonomic Cluster Management System (ACMS) with Reflex Autonomicity

NASA Technical Reports Server (NTRS)

Truszkowski, Walt; Hinchey, Mike; Sterritt, Roy

2005-01-01

Cluster computing, whereby a large number of simple processors or nodes are combined together to apparently function as a single powerful computer, has emerged as a research area in its own right. The approach offers a relatively inexpensive means of providing a fault-tolerant environment and achieving significant computational capabilities for high-performance computing applications. However, the task of manually managing and configuring a cluster quickly becomes daunting as the cluster grows in size. Autonomic computing, with its vision to provide self-management, can potentially solve many of the problems inherent in cluster management. We describe the development of a prototype Autonomic Cluster Management System (ACMS) that exploits autonomic properties in automating cluster management and its evolution to include reflex reactions via pulse monitoring.

Differences in dichogamy and herkogamy contribute to higher selfing in contrasting environments in the annual Blackstonia perfoliata (Gentianaceae)

PubMed Central

Brys, Rein; Geens, Bram; Beeckman, Tom; Jacquemyn, Hans

2013-01-01

Background and Aims The establishment of plant populations in novel environments may generate pronounced shifts in floral traits and plant mating systems, particularly when pollinators are scarce. In this study, floral morphology and mating system functioning are compared between recently established and older populations of the annual plant Blackstonia perfoliata that occur in different pollinator environments. Methods Hand-pollination and emasculation experiments were conducted to assess the extent of pollinator-mediated pollen deposition and pollen limitation, and the contribution of autonomous selfing to total seed production. Detailed measurements of key floral traits were performed to compare the flower morphology and mating system functioning between plants from both pollination environments. Key Results Pollinator-mediated pollen deposition was about twice as low in the recently colonized and pollinator-poor environment compared with the old and pollinator-rich sites, but total seed set was little affected by any type of pollen limitation. The contribution of autonomous selfing to total seed production was higher in the pollinator-poor sites than in the pollinator-rich sites (index of reproductive assurance = 0·56 and 0·17, respectively), and seed production was only poorly affected by selfing, whereas in the pollinator-rich populations selfing reduced total reproductive output by about 40 % compared with outcross pollination. Plants originating from pollinator-poor environments produced smaller flowers that showed significantly lower levels of dichogamy (i.e. protogyny) and herkogamy. These reductions resulted in a 2-fold higher capacity for autonomous selfing under pollinator-free conditions (index of autonomous selfing = 0·81 and 0·41 in plants originating from the pollinator-poor and pollinator-rich environment, respectively). Conclusions The results illustrate that plant populations colonizing novel environments can differ markedly in floral morphology and mating system functioning. Due to a temporal shift in the male phase, the breeding system of B. perfoliata shifted from delayed selfing under pollinator-rich conditions towards competing selfing in recently established populations, providing greater reproductive assurance when pollinators and/or reproductive partners are limited. PMID:23408833

Aerobic exercise training delays cardiac dysfunction and improves autonomic control of circulation in diabetic rats undergoing myocardial infarction.

PubMed

Rodrigues, Bruno; Jorge, Luciana; Mostarda, Cristiano T; Rosa, Kaleizu T; Medeiros, Alessandra; Malfitano, Christiane; de Souza, Alcione L; Viegas, Katia Aparecida da Silva; Lacchini, Silvia; Curi, Rui; Brum, Patricia C; De Angelis, Kátia; Irigoyen, Maria Cláudia

2012-09-01

Exercise training (ET) has been used as a nonpharmacological strategy for treatment of diabetes and myocardial infarction (MI) separately. We evaluated the effects ET on functional and molecular left ventricular (LV) parameters as well as on autonomic function and mortality in diabetics after MI. Male Wistar rats were divided into control (C), sedentary-diabetic infarcted (SDI), and trained-diabetic infarcted (TDI) groups. MI was induced after 15 days of streptozotocin-diabetes induction. Seven days after MI, the trained group underwent ET protocol (90 days, 50-70% maximal oxygen consumption-VO(2)max). LV function was evaluated noninvasively and invasively; baroreflex sensitivity, pulse interval variability, cardiac output, tissue blood flows, VEGF mRNA and protein, HIF1-α mRNA, and Ca(2+) handling proteins were measured. MI area was reduced in TDI (21 ± 4%) compared with SDI (38 ± 4%). ET induced improvement in cardiac function, hemodynamics, and tissue blood flows. These changes were probable consequences of a better expression of Ca(2+) handling proteins, increased VEGF mRNA and protein expression as well as improvement in autonomic function, that resulted in reduction of mortality in TDI (33%) compared with SDI (68%) animals. ET reduced cardiac and peripheral dysfunction and preserved autonomic control in diabetic infarcted rats. Consequently, these changes resulted in improved VO(2)max and survival after MI. Copyright © 2012 Elsevier Inc. All rights reserved.

Is There an Association Between Markers of Cardiovascular Autonomic Dysfunction at Discharge From Rehabilitation and Participation 1 and 5 Years Later in Individuals With Spinal Cord Injury?

PubMed

Rianne Ravensbergen, H J; de Groot, Sonja; Post, Marcel W; Bongers-Janssen, Helma M; van der Woude, Lucas H; Claydon, Victoria E

2016-09-01

To determine whether physical activity and participation 1 and 5 years after discharge are associated with measures of cardiovascular autonomic function: prevalence of hypotension and reduced peak heart rate at discharge from initial inpatient spinal cord injury (SCI) rehabilitation. Prospective cohort study. Rehabilitation centers. Individuals with SCI (N=146). Not applicable. We recorded markers of cardiovascular autonomic dysfunction (resting blood pressure and peak heart rate) and personal and lesion characteristics at the time of discharge from rehabilitation. Parameters for participation (social health status dimension of the Sickness Impact Profile) and physical activity (Physical Activity Scale for Individuals with Physical Disabilities [PASIPD]) were measured 1 and 5 years after discharge. Effects of prevalence of cardiovascular autonomic dysfunction were analyzed using linear regression analysis while correcting for possible confounders. We found no significant association between hypotension and social health status dimension of the Sickness Impact Profile or PASIPD, either at 1 or at 5 years after discharge. A significant association between peak heart rate and social health status dimension of the Sickness Impact Profile was found at 1 year after discharge, showing poorer participation in individuals with low peak heart rate (ie, cardiovascular autonomic dysfunction). The unadjusted relation between peak heart rate and the social health status dimension of the Sickness Impact Profile was significant at 5 years, but not when adjusted for confounders. We found associations between peak heart rate and PASIPD for both 1 and 5 years after discharge; however, these were not significant after correction for potential confounding factors. Autonomic dysfunction after SCI is a crucial factor influencing quality of life. We found that cardiovascular autonomic impairment, assessed from low peak heart rate, was associated with reduced participation after 1 year. The results suggest that peak heart rate at discharge from rehabilitation after SCI should be used to identify those needing additional support to facilitate physical activity and participation after discharge. Copyright © 2016 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

Pain in dementia: prevalence and associated factors: protocol of a multidisciplinary study.

PubMed

van Kooten, Janine; Delwel, Suzanne; Binnekade, Tarik T; Smalbrugge, Martin; van der Wouden, Johannes C; Perez, Roberto S G M; Rhebergen, Didi; Zuurmond, Wouter W A; Stek, Max L; Lobbezoo, Frank; Hertogh, Cees M P M; Scherder, Erik J A

2015-03-21

Pain is a common problem in people with dementia, however the exact prevalence of pain in dementia subtypes, e.g. Alzheimer's Disease (AD), Vascular Dementia (VaD), Frontotemporal Dementia (FTD) and dementia with Lewy Bodies (DLB), is unknown, as is the relation between pain and the different subtypes of dementia. In this study, the prevalence of pain in people with dementia will be investigated per dementia subtype and the relationship between the various subtypes of dementia and the presence of specific types of pain (i.e. musculoskeletal pain, neuropathic pain and orofacial pain) will be examined. Secondly, associations between various types of pain, cognitive functioning, neuropsychiatric symptoms and quality of life in people with dementia will be examined. A third purpose is to study the value of the assessment of autonomic responses in assessing pain in people with dementia. Finally, the effect of feedback to the attending physician on the presence of pain, based on examination by investigators with backgrounds in neuropsychology, geriatric dentistry and elderly care medicine, will be evaluated. A cross-sectional, partially longitudinal observational study in 400 participants with dementia, aged 60 years and older. Participants will be recruited from an outpatient memory clinic and dementia special care units. All participants will be examined by an elderly care medicine trainee, a dentist with experience in geriatric dentistry, and a neuropsychologist. The primary outcome is presence of pain. Secondary outcomes will include oral health, autonomic responses to pain stimulus, vital sensibility and gnostic sensibility, musculoskeletal examination, cognitive functioning, neuropsychiatric symptoms, and quality of life. This study will help to enhance our knowledge regarding the prevalence of different types of pain in different dementia subtypes i.e. AD, VaD, FTD and DLB. This study also aims to contribute to a better understanding of oral health status in people with dementia, the use of autonomic responses in the assessment of pain in people with dementia and the relationships between pain and cognitive symptoms, neuropsychiatric symptoms and quality of life in people with various dementia subtypes and in different stages of the disease.

A Multifunctional Coating for Autonomous Corrosion Control

NASA Technical Reports Server (NTRS)

Calle, Luz M.; Li, Wenyan; Buhrow, Jerry W.; Jolley, Scott t.

2011-01-01

Nearly all metals and their alloys are subject to corrosion that causes them to lose their structural integrity or other critical functionality. Protective coatings are the most commonly used method of corrosion control. However, progressively stricter environmental regulations have resulted in the ban of many commercially available corrosion protective coatings due to the harmful effects of their solvents or corrosion inhibitors. This work concerns the development of a multifunctional smart coating for the autonomous control of corrosion. This coating is being developed to have the inherent ability to detect the chemical changes associated with the onset of corrosion and respond autonomously to indicate it and control it. The multi-functionality of the coating is based on microencapsulation technology specifically designed for corrosion control applications. This design has, in addition to all the advantages of existing microcapsulation designs, the corrosion controlled release function that triggers the delivery of corrosion indicators and inhibitors on demand, only when and where needed. Microencapsulation of self-healing agents for autonomous repair of mechanical damage to the coating is also being pursued. Corrosion indicators, corrosion inhibitors, as well as self-healing agents, have been encapsulated and dispersed into several paint systems to test the corrosion detection, inhibition, and self-healing properties of the coating. Key words: Corrosion, coating, autonomous corrosion control, corrosion indication, corrosion inhibition, self-healing coating, smart coating, multifunctional coating, microencapsulation.

Assessment of the Autonomous Learning Competence in Engineering Degree Courses at the Universitat Politècnica De Catalunya

ERIC Educational Resources Information Center

Olmedo-Torre, Noelia; Farrerons Vidal, Oscar

2017-01-01

We present a strategy for the acquisition and assessment of autonomous learning conducted as part of the Graphic Expression in Engineering (GE) degree course during the first quarter at the Escola Universitària d'Enginyeria Tècnica Industrial de Barcelona (EUETIB). The strategy employed is the puzzle technique in the classroom and multiple-choice…

Role of Autonomic Reflex Arcs in Cardiovascular Responses to Air Pollution Exposure

EPA Science Inventory

The body responds to environmental stressors by triggering autonomic reflexes in the pulmonary receptors, baroreceptors, and chemoreceptors to maintain homeostasis. Numerous studies have shown that exposure to various gases and airborne particles can alter the functional outcome ...

Children with Autism Show Altered Autonomic Adaptation to Novel and Familiar Social Partners.

PubMed

Neuhaus, Emily; Bernier, Raphael A; Beauchaine, Theodore P

2016-05-01

Social deficits are fundamental to autism spectrum disorder (ASD), and a growing body of research implicates altered functioning of the autonomic nervous system (ANS), including both sympathetic and parasympathetic branches. However, few studies have explored both branches concurrently in ASD, particularly within the context of social interaction. The current study investigates patterns of change in indices of sympathetic (pre-ejection period; PEP) and parasympathetic (respiratory sinus arrhythmia; RSA) cardiac influence as boys (ages 8-11 years) with (N = 18) and without (N = 18) ASD engage in dyadic social interaction with novel and familiar social partners. Groups showed similar patterns of autonomic change during interaction with the novel partner, but differed in heart rate, PEP, and RSA reactivity while interacting with a familiar partner. Boys without ASD evinced decreasing sympathetic and increasing parasympathetic influence, whereas boys with ASD increased in sympathetic influence. Boys without ASD also demonstrated more consistent ANS responses across partners than those with ASD, with parasympathetic responding differentiating familiar and novel interaction partners. Finally, PEP slopes with a familiar partner correlated with boys' social skills. Implications include the importance of considering autonomic state during clinical assessment and treatment, and the potential value of regulation strategies as a complement to intervention programs aiming to support social cognition and behavior. Autism Res 2016, 9: 579-591. © 2015 International Society for Autism Research, Wiley Periodicals, Inc. © 2015 International Society for Autism Research, Wiley Periodicals, Inc.

Autonomic Correlates of Speech Versus Nonspeech Tasks in Children and Adults

PubMed Central

Arnold, Hayley S.; MacPherson, Megan K.; Smith, Anne

2015-01-01

Purpose To assess autonomic arousal associated with speech and nonspeech tasks in school-age children and young adults. Method Measures of autonomic arousal (electrodermal level, electrodermal response amplitude, blood pulse volume, and heart rate) were recorded prior to, during, and after the performance of speech and nonspeech tasks by twenty 7- to 9-year-old children and twenty 18- to 22-year-old adults. Results Across age groups, autonomic arousal was higher for speech tasks compared with nonspeech tasks, based on peak electrodermal response amplitude and blood pulse volume. Children demonstrated greater relative arousal, based on heart rate and blood pulse volume, for nonspeech oral motor tasks than adults but showed similar mean arousal levels for speech tasks as adults. Children demonstrated sex differences in autonomic arousal; specifically, autonomic arousal remained high for school-age boys but not girls in a more complex open-ended narrative task that followed a simple sentence production task. Conclusions Speech tasks elicit greater autonomic arousal than nonspeech tasks, and children demonstrate greater autonomic arousal for nonspeech oral motor tasks than adults. Sex differences in autonomic arousal associated with speech tasks in school-age children are discussed relative to speech-language differences between boys and girls. PMID:24686989

Music therapy, emotions and the heart: a pilot study.

PubMed

Raglio, Alfredo; Oasi, Osmano; Gianotti, Marta; Bellandi, Daniele; Manzoni, Veronica; Goulene, Karine; Imbriani, Chiara; Badiale, Marco Stramba

2012-01-01

The autonomic nervous system plays an important role in the control of cardiac function. It has been suggested that sound and music may have effects on the autonomic control of the heart inducing emotions, concomitantly with the activation of specific brain areas, i.e. the limbic area, and they may exert potential beneficial effects. This study is a prerequisite and defines a methodology to assess the relation between changes in cardiac physiological parameters such as heart rate, QT interval and their variability and the psychological responses to music therapy sessions. We assessed the cardiac physiological parameters and psychological responses to a music therapy session. ECG Holter recordings were performed before, during and after a music therapy session in 8 healthy individuals. The different behaviors of the music therapist and of the subjects have been analyzed with a specific music therapy assessment (Music Therapy Checklist). After the session mean heart rate decreased (p = 0.05), high frequency of heart rate variability tended to be higher and QTc variability tended to be lower. During music therapy session "affect attunements" have been found in all subjects but one. A significant emotional activation was associated to a higher dynamicity and variations of sound-music interactions. Our results may represent the rational basis for larger studies in diferent clinical conditions.

Mobile Phone-Based Joint Angle Measurement for Functional Assessment and Rehabilitation of Proprioception

PubMed Central

Mourcou, Quentin; Fleury, Anthony; Diot, Bruno; Franco, Céline; Vuillerme, Nicolas

2015-01-01

Assessment of joint functional and proprioceptive abilities is essential for balance, posture, and motor control rehabilitation. Joint functional ability refers to the capacity of movement of the joint. It may be evaluated thereby measuring the joint range of motion (ROM). Proprioception can be defined as the perception of the position and of the movement of various body parts in space. Its role is essential in sensorimotor control for movement acuity, joint stability, coordination, and balance. Its clinical evaluation is commonly based on the assessment of the joint position sense (JPS). Both ROM and JPS measurements require estimating angles through goniometer, scoliometer, laser-pointer, and bubble or digital inclinometer. With the arrival of Smartphones, these costly clinical tools tend to be replaced. Beyond evaluation, maintaining and/or improving joint functional and proprioceptive abilities by training with physical therapy is important for long-term management. This review aims to report Smartphone applications used for measuring and improving functional and proprioceptive abilities. It identifies that Smartphone applications are reliable for clinical measurements and are mainly used to assess ROM and JPS. However, there is lack of studies on Smartphone applications which can be used in an autonomous way to provide physical therapy exercises at home. PMID:26583101

The crosstalk between autonomic nervous system and blood vessels

PubMed Central

Sheng, Yulan; Zhu, Li

2018-01-01

The autonomic nervous system (ANS), comprised of two primary branches, sympathetic and parasympathetic nervous system, plays an essential role in the regulation of vascular wall contractility and tension. The sympathetic and parasympathetic nerves work together to balance the functions of autonomic effector organs. The neurotransmitters released from the varicosities in the ANS can regulate the vascular tone. Norepinephrine (NE), adenosine triphosphate (ATP) and Neuropeptide Y (NPY) function as vasoconstrictors, whereas acetylcholine (Ach) and calcitonin gene-related peptide (CGRP) can mediate vasodilation. On the other hand, vascular factors, such as endothelium-derived relaxing factor nitric oxide (NO), and constriction factor endothelin, play an important role in the autonomic nervous system in physiologic conditions. Endothelial dysfunction and inflammation are associated with the sympathetic nerve activity in the pathological conditions, such as hypertension, heart failure, and diabetes mellitus. The dysfunction of the autonomic nervous system could be a risk factor for vascular diseases and the overactive sympathetic nerve is detrimental to the blood vessel. In this review, we summarize findings concerning the crosstalk between ANS and blood vessels in both physiological and pathological conditions and hope to provide insight into the development of therapeutic interventions of vascular diseases. PMID:29593847

Development and Evaluation of an Airborne Separation Assurance System for Autonomous Aircraft Operations

NASA Technical Reports Server (NTRS)

Barhydt, Richard; Palmer, Michael T.; Eischeid, Todd M.

2004-01-01

NASA Langley Research Center is developing an Autonomous Operations Planner (AOP) that functions as an Airborne Separation Assurance System for autonomous flight operations. This development effort supports NASA s Distributed Air-Ground Traffic Management (DAG-TM) operational concept, designed to significantly increase capacity of the national airspace system, while maintaining safety. Autonomous aircraft pilots use the AOP to maintain traffic separation from other autonomous aircraft and managed aircraft flying under today's Instrument Flight Rules, while maintaining traffic flow management constraints assigned by Air Traffic Service Providers. AOP is designed to facilitate eventual implementation through careful modeling of its operational environment, interfaces with other aircraft systems and data links, and conformance with established flight deck conventions and human factors guidelines. AOP uses currently available or anticipated data exchanged over modeled Arinc 429 data buses and an Automatic Dependent Surveillance Broadcast 1090 MHz link. It provides pilots with conflict detection, prevention, and resolution functions and works with the Flight Management System to maintain assigned traffic flow management constraints. The AOP design has been enhanced over the course of several experiments conducted at NASA Langley and is being prepared for an upcoming Joint Air/Ground Simulation with NASA Ames Research Center.

Exercise improves cardiac autonomic function in obesity and diabetes.

PubMed

Voulgari, Christina; Pagoni, Stamatina; Vinik, Aaron; Poirier, Paul

2013-05-01

Physical activity is a key element in the prevention and management of obesity and diabetes. Regular physical activity efficiently supports diet-induced weight loss, improves glycemic control, and can prevent or delay type 2 diabetes diagnosis. Furthermore, physical activity positively affects lipid profile, blood pressure, reduces the rate of cardiovascular events and associated mortality, and restores the quality of life in type 2 diabetes. However, recent studies have documented that a high percentage of the cardiovascular benefits of exercise cannot be attributed solely to enhanced cardiovascular risk factor modulation. Obesity in concert with diabetes is characterized by sympathetic overactivity and the progressive loss of cardiac parasympathetic influx. These are manifested via different pathogenetic mechanisms, including hyperinsulinemia, visceral obesity, subclinical inflammation and increased thrombosis. Cardiac autonomic neuropathy is an underestimated risk factor for the increased cardiovascular morbidity and mortality associated with obesity and diabetes. The same is true for the role of physical exercise in the restoration of the heart cardioprotective autonomic modulation in these individuals. This review addresses the interplay of cardiac autonomic function in obesity and diabetes, and focuses on the importance of exercise in improving cardiac autonomic dysfunction. Copyright © 2013 Elsevier Inc. All rights reserved.

Pulse wave velocity and cardiac autonomic function in type 2 diabetes mellitus.

PubMed

Chorepsima, Stamatina; Eleftheriadou, Ioanna; Tentolouris, Anastasios; Moyssakis, Ioannis; Protogerou, Athanasios; Kokkinos, Alexandros; Sfikakis, Petros P; Tentolouris, Nikolaos

2017-05-19

Increased carotid-femoral pulse wave velocity (PWV) has been associated with incident cardiovascular disease, independently of traditional risk factors. Cardiac autonomic dysfunction is a common complication of diabetes and has been associated with reduced aortic distensibility. However, the association of cardiac autonomic dysfunction with PWV is not known. In this study we examined the association between cardiac autonomic function and PWV in subjects with type 2 diabetes mellitus. A total of 290 patients with type 2 diabetes were examined. PWV was measured at the carotid-femoral segment with applanation tonometry. Central mean arterial blood pressure (MBP) was determined by the same apparatus. Participants were classified as having normal (n = 193) or abnormal (n = 97) PWV values using age-corrected values. Cardiac autonomic nervous system activity was determined by measurement of parameters of heart rate variability (HRV). Subjects with abnormal PWV were older, had higher arterial blood pressure and higher heart rate than those with normal PWV. Most of the values of HRV were significantly lower in subjects with abnormal than in those with normal PWV. Multivariate analysis, after controlling for various confounding factors, demonstrated that abnormal PWV was associated independently only with peripheral MBP [odds ratio (OR) 1.049, 95% confidence intervals (CI) 1.015-1.085, P = 0.005], central MBP (OR 1.052, 95% CI 1.016-1.088, P = 0.004), log total power (OR 0.490, 95% CI 0.258-0.932, P = 0.030) and log high frequency power (OR 0.546, 95% CI 0.301-0.991, P = 0.047). In subjects with type 2 diabetes, arterial blood pressure and impaired cardiac autonomic function is associated independently with abnormal PWV.

Dysfunction of autonomic nervous system in childhood obesity: a cross-sectional study.

PubMed

Baum, Petra; Petroff, David; Classen, Joseph; Kiess, Wieland; Blüher, Susann

2013-01-01

To assess the distribution of autonomic nervous system (ANS) dysfunction in overweight and obese children. Parasympathetic and sympathetic ANS function was assessed in children and adolescents with no evidence of impaired glucose metabolism by analysis of heart rate variability (low frequency power ln(LF), high frequency power, ln(HF); ln(LF/HF) ratio, ratio of longest RR interval during expiration to shortest interval during inspiration (E/I ratio), root mean square of successive differences (RMSSD); sympathetic skin response (SSR); and quantitative pupillography (pupil diameter in darkness, light reflex amplitude, latency, constriction velocity, re-dilation velocity). The relationship of each ANS variable to the standard deviation score of body mass index (BMI-SDS) was assessed in a linear model considering age, gender and pubertal stage as co-variates and employing an F-statistic to compare the fit of nested models. Group comparisons between normal weight and obese children as well as an analysis of dependence on insulin resistance (as indexed by the Homeostasis Model Assessment of Insulin Resistance, HOMA-IR) were performed for parameters shown to correlate with BMI-SDS. Statistical significance was set at 5%. Measurements were performed in 149 individuals (mean age 12.0 y; 90 obese 45 boys; 59 normal weight, 34 boys). E/I ratio (p = 0.003), ln(HF) (p = 0.03), pupil diameter in darkness (p = 0.01) were negatively correlated with BMI-SDS, whereas ln(LF/HF) was positively correlated (p = 0.05). Early re-dilation velocity was in trend negatively correlated to BMI-SDS (p = 0.08). None of the parameters that depended significantly on BMI-SDS was found to be significantly correlated with HOMA-IR. These findings demonstrate extended ANS dysfunction in obese children and adolescents, affecting several organ systems. Both parasympathetic activity and sympathetic activity are reduced. The conspicuous pattern of ANS dysfunction raises the possibility that obesity may give rise to dysfunction of the peripheral autonomic nerves resembling that observed in normal-weight diabetic children and adolescents.

Dynamic characteristics of heart rate control by the autonomic nervous system in rats.

PubMed

Mizuno, Masaki; Kawada, Toru; Kamiya, Atsunori; Miyamoto, Tadayoshi; Shimizu, Shuji; Shishido, Toshiaki; Smith, Scott A; Sugimachi, Masaru

2010-09-01

We estimated the transfer function of autonomic heart rate (HR) control by using random binary sympathetic or vagal nerve stimulation in anaesthetized rats. The transfer function from sympathetic stimulation to HR response approximated a second-order, low-pass filter with a lag time (gain, 4.29 +/- 1.55 beats min(1) Hz(1); natural frequency, 0.07 +/- 0.03 Hz; damping coefficient, 1.96 +/- 0.64; and lag time, 0.73 +/- 0.12 s). The transfer function from vagal stimulation to HR response approximated a first-order, low-pass filter with a lag time (gain, 8.84 +/- 4.51 beats min(1) Hz(1); corner frequency, 0.12 +/- 0.06 Hz; and lag time, 0.12 +/- 0.08 s). These results suggest that the dynamic characteristics of HR control by the autonomic nervous system in rats are similar to those of larger mammals.

Swarm autonomic agents with self-destruct capability

NASA Technical Reports Server (NTRS)

Hinchey, Michael G. (Inventor); Sterritt, Roy (Inventor)

2009-01-01

Systems, methods and apparatus are provided through which in some embodiments an autonomic entity manages a system by generating one or more stay alive signals based on the functioning status and operating state of the system. In some embodiments, an evolvable synthetic neural system is operably coupled to one or more evolvable synthetic neural systems in a hierarchy. The evolvable neural interface receives and generates heartbeat monitor signals and pulse monitor signals that are used to generate a stay alive signal that is used to manage the operations of the synthetic neural system. In another embodiment an asynchronous Alice signal (Autonomic license) requiring valid credentials of an anonymous autonomous agent is initiated. An unsatisfactory Alice exchange may lead to self-destruction of the anonymous autonomous agent for self-protection.

Swarm autonomic agents with self-destruct capability

NASA Technical Reports Server (NTRS)

Hinchey, Michael G. (Inventor); Sterritt, Roy (Inventor)

2011-01-01

Systems, methods and apparatus are provided through which in some embodiments an autonomic entity manages a system by generating one or more stay alive signals based on the functioning status and operating state of the system. In some embodiments, an evolvable synthetic neural system is operably coupled to one or more evolvable synthetic neural systems in a hierarchy. The evolvable neural interface receives and generates heartbeat monitor signals and pulse monitor signals that are used to generate a stay alive signal that is used to manage the operations of the synthetic neural system. In another embodiment an asynchronous Alice signal (Autonomic license) requiring valid credentials of an anonymous autonomous agent is initiated. An unsatisfactory Alice exchange may lead to self-destruction of the anonymous autonomous agent for self-protection.

Autonomic nervous function in patients with Meniere's disease evaluated by power spectral analysis of heart rate variability.

PubMed

Yamada, M; Mizuta, K; Ito, Y; Furuta, M; Sawai, S; Miyata, H

1999-10-01

A hypothesis has been advanced that the autonomic nervous dysfunction (AND) relates to the development of vertigo in Meniere's disease (MD). We also studied the causal relationship between AND and vertigo in MD. We evaluated autonomic nervous function in 17 patients with MD (five men and 12 women ranging in age from 16 to 70 years) by classifying them by their stages of attack and interval of vertigo and with power spectral analysis (PSA) of heart rate variability. Fourteen healthy volunteers were also tested as controls. At the interval stage, parasympathetic nervous hypofunction and significant depression of sympathetic response due to postural changes from the supine to the standing position were observed in many of those patients. At the attack stage, sympathetic nervous hypofunction was observed in some of the patients. These findings lead us to the conclusion that AND relates to vertigo in MD as a predisposing factor. However, the question of whether AND relates as a trigger or as a consequence of vertigo in MD has not been adequately solved in this study. We will make further studies on circadian variation of autonomic nervous function.

High Intensity Aerobic Exercise Training Improves Deficits of Cardiovascular Autonomic Function in a Rat Model of Type 1 Diabetes Mellitus with Moderate Hyperglycemia

PubMed Central

Grisé, Kenneth N.; Olver, T. Dylan; McDonald, Matthew W.; Dey, Adwitia; Jiang, Mao; Lacefield, James C.; Shoemaker, J. Kevin; Noble, Earl G.; Melling, C. W. James

2016-01-01

Indices of cardiovascular autonomic neuropathy (CAN) in experimental models of Type 1 diabetes mellitus (T1DM) are often contrary to clinical data. Here, we investigated whether a relatable insulin-treated model of T1DM would induce deficits in cardiovascular (CV) autonomic function more reflective of clinical results and if exercise training could prevent those deficits. Sixty-four rats were divided into four groups: sedentary control (C), sedentary T1DM (D), control exercise (CX), or T1DM exercise (DX). Diabetes was induced via multiple low-dose injections of streptozotocin and blood glucose was maintained at moderate hyperglycemia (9–17 mM) through insulin supplementation. Exercise training consisted of daily treadmill running for 10 weeks. Compared to C, D had blunted baroreflex sensitivity, increased vascular sympathetic tone, increased serum neuropeptide Y (NPY), and decreased intrinsic heart rate. In contrast, DX differed from D in all measures of CAN (except NPY), including heart rate variability. These findings demonstrate that this T1DM model elicits deficits and exercise-mediated improvements to CV autonomic function which are reflective of clinical T1DM. PMID:26885531

Autonomous Rendezvous and Docking Conference, volume 1

NASA Technical Reports Server (NTRS)

1990-01-01

This document consists of the presentation submitted at the Autonomous Rendezvous and Docking (ARD) Conference. It contains three volumes: ARD hardware technology; ARD software technology; and ARD operations. The purpose of this conference is to identify the technologies required for an on orbit demonstration of the ARD, assess the maturity of these technologies, and provide the necessary insight for a quality assessment of the programmatic management, technical, schedule, and cost risks.

Autonomous Rendezvous and Docking Conference, volume 3

NASA Technical Reports Server (NTRS)

1990-01-01

This document consists of the presentation submitted at the Autonomous Rendezvous and Docking (ARD) Conference. The document contains three volumes: ARD hardware technology; ARD software technology; and ARD operations. The purpose of this conference is to identify the technologies required for an on orbit demonstration of ARD, assess the maturity of these technologies, and provide the necessary insight for a quality assessment of programmatic management, technical, schedule, and cost risks.

Resting sympathetic arousal moderates the association between parasympathetic reactivity and working memory performance in adults reporting high levels of life stress.

PubMed

Giuliano, Ryan J; Gatzke-Kopp, Lisa M; Roos, Leslie E; Skowron, Elizabeth A

2017-08-01

The neurovisceral integration model stipulates that autonomic function plays a critical role in the regulation of higher-order cognitive processes, yet most work to date has examined parasympathetic function in isolation from sympathetic function. Furthermore, the majority of work has been conducted on normative samples, which typically demonstrate parasympathetic withdrawal to increase arousal needed to complete cognitive tasks. Little is known about how autonomic regulation supports cognitive function in populations exposed to high levels of stress, which is critical given that chronic stress exposure alters autonomic function. To address this, we sought to characterize how parasympathetic (high-frequency heart rate variability, HF-HRV) and sympathetic (preejection period, PEP) measures of cardiac function contribute to individual differences in working memory (WM) capacity in a sample of high-risk women. HF-HRV and PEP were measured at rest and during a visual change detection measure of WM. Multilevel modeling was used to examine within-person fluctuations in WM performance throughout the task concurrently with HF-HRV and PEP, as well as between-person differences as a function of resting HF-HRV and PEP levels. Results indicate that resting PEP moderated the association between HF-HRV reactivity and WM capacity. Increases in WM capacity across the task were associated with increases in parasympathetic activity, but only among individuals with longer resting PEP (lower sympathetic arousal). Follow-up analyses showed that shorter resting PEP was associated with greater cumulative risk exposure. These results support the autonomic space framework, in that the relationship between behavior and parasympathetic function appears dependent on resting sympathetic activation. © 2017 Society for Psychophysiological Research.

Resting sympathetic arousal moderates the association between parasympathetic reactivity and working memory performance in adults reporting high levels of life stress

PubMed Central

Giuliano, Ryan J.; Gatzke-Kopp, Lisa M.; Roos, Leslie E.; Skowron, Elizabeth A.

2017-01-01

The neurovisceral integration model stipulates that autonomic function plays a critical role in the regulation of higher-order cognitive processes, yet most work to date has examined parasympathetic function in isolation from sympathetic function. Furthermore, the majority of work has been conducted on normative samples, which typically demonstrate parasympathetic withdrawal to increase arousal needed to complete cognitive tasks. Little is known about how autonomic regulation supports cognitive function in populations exposed to high levels of stress, which is critical given that chronic stress exposure alters autonomic function. To address this, we sought to characterize how parasympathetic (high-frequency heart rate variability, HF-HRV) and sympathetic (preejection period, PEP) measures of cardiac function contribute to individual differences in working memory (WM) capacity in a sample of high-risk women. HF-HRV and PEP were measured at rest and during a visual change detection measure of WM. Multilevel modeling was used to examine within-person fluctuations in WM performance throughout the task concurrently with HF-HRV and PEP, as well as between-person differences as a function of resting HF-HRV and PEP levels. Results indicate that resting PEP moderated the association between HF-HRV reactivity and WM capacity. Increases in WM capacity across the task were associated with increases in parasympathetic activity, but only among individuals with longer resting PEP (lower sympathetic arousal). Follow-up analyses showed that shorter resting PEP was associated with greater cumulative risk exposure. These results support the autonomic space framework, in that the relationship between behavior and parasympathetic function appears dependent on resting sympathetic activation. PMID:28449242

AUTONOMIC AXONS IN THE HUMAN ENDOCRINE PANCREAS SHOW UNIQUE INNERVATION PATTERNS

PubMed Central

Rodriguez-Diaz, Rayner; Abdulreda, Midhat H.; Formoso, Alexander L.; Gans, Itai; Ricordi, Camillo; Berggren, Per-Olof; Caicedo, Alejandro

2011-01-01

SUMMARY The autonomic nervous system regulates hormone secretion from the endocrine pancreas, the islets of Langerhans, and thus impacts glucose metabolism. The parasympathetic and sympathetic nerves innervate the pancreatic islet, but the precise innervation patterns are not known, particularly in human islets. Here we demonstrate that the innervation of human islets is different from that of mouse islets and that it does not conform to existing models of autonomic control of islet function. By visualizing axons in three dimensions and quantifying axonal densities and contacts within pancreatic islets, we found that, in contrast to mouse endocrine cells, human endocrine cells are sparsely contacted by autonomic axons. Few parasympathetic cholinergic axons penetrate the human islet and the invading sympathetic fibers preferentially innervate smooth muscle cells of blood vessels located within the islet. Thus, rather than modulating endocrine cell function directly, sympathetic nerves may regulate hormone secretion in human islets by controlling local blood flow or by acting on islet regions located downstream. PMID:21723503

Sandia National Laboratories proof-of-concept robotic security vehicle

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

Harrington, J.J.; Jones, D.P.; Klarer, P.R.

1989-01-01

Several years ago Sandia National Laboratories developed a prototype interior robot that could navigate autonomously inside a large complex building to air and test interior intrusion detection systems. Recently the Department of Energy Office of Safeguards and Security has supported the development of a vehicle that will perform limited security functions autonomously in a structured exterior environment. The goal of the first phase of this project was to demonstrate the feasibility of an exterior robotic vehicle for security applications by using converted interior robot technology, if applicable. An existing teleoperational test bed vehicle with remote driving controls was modified andmore » integrated with a newly developed command driving station and navigation system hardware and software to form the Robotic Security Vehicle (RSV) system. The RSV, also called the Sandia Mobile Autonomous Navigator (SANDMAN), has been successfully used to demonstrate that teleoperated security vehicles which can perform limited autonomous functions are viable and have the potential to decrease security manpower requirements and improve system capabilities. 2 refs., 3 figs.« less

Solar Thermal Utility-Scale Joint Venture Program (USJVP) Final Report

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

MANCINI,THOMAS R.

2001-04-01

Several years ago Sandia National Laboratories developed a prototype interior robot [1] that could navigate autonomously inside a large complex building to aid and test interior intrusion detection systems. Recently the Department of Energy Office of Safeguards and Security has supported the development of a vehicle that will perform limited security functions autonomously in a structured exterior environment. The goal of the first phase of this project was to demonstrate the feasibility of an exterior robotic vehicle for security applications by using converted interior robot technology, if applicable. An existing teleoperational test bed vehicle with remote driving controls was modifiedmore » and integrated with a newly developed command driving station and navigation system hardware and software to form the Robotic Security Vehicle (RSV) system. The RSV, also called the Sandia Mobile Autonomous Navigator (SANDMAN), has been successfully used to demonstrate that teleoperated security vehicles which can perform limited autonomous functions are viable and have the potential to decrease security manpower requirements and improve system capabilities.« less

Impact of exercise training associated to pyridostigmine treatment on autonomic function and inflammatory profile after myocardial infarction in rats.

PubMed

Feriani, Daniele J; Souza, Gabriel I H; Carrozzi, Nicolle M; Mostarda, Cristiano; Dourado, Paulo M M; Consolim-Colombo, Fernanda M; De Angelis, Kátia; Moreno, Heitor; Irigoyen, Maria Cláudia; Rodrigues, Bruno

2017-01-15

The effects of exercise training (ET) associated with pyridostigmine bromide (PYR) treatment on cardiac and autonomic function, as well as on inflammatory profile after myocardial infarction (MI), are unclear. Male Wistar rats were randomly assigned to: control (C); sedentary+infarcted (I); sedentary+infarcted treated with PYR (IP); infarcted submitted to aerobic exercise training (IT); and infarcted submitted to treatment with PYR and aerobic exercise training (ITP). After 12weeks of ET (50-70% maximal running speed; 1h a day, 5days a week) and/or PYR treatment (0.14mg/mL on drink water), hemodynamic, autonomic and cytokines expression were performed. We observed that both aerobic ET, associated or not with PYR treatment in MI animals, were able to: reduced MI area, improved systolic and diastolic function, baroreflex sensitivity, cardiovascular autonomic modulation, and tonic activity of the sympathetic and parasympathetic nervous system. Also, they led to a reduction of inflammatory profile measured at plasma, left ventricle and soleus skeletal muscle. However, additional effects were observed when ET and PYR were associated, such as an increase in vagal tonus and modulation, reduction of MI area, interferon-γ and tumor necrosis factor-α (TNF-α), as well as an increase of interleukin-10/TNF-α ratio on left ventricle. These data suggest that associating ET and PYR promotes some additional benefits on cardiovascular autonomic modulation and inflammatory profile in infarcted rats. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Dysfunctional penile cholinergic nerves in diabetic impotent men

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

Blanco, R.; Saenz de Tejada, I.; Goldstein, I.

1990-08-01

Impotence in the diabetic man may be secondary to a neuropathic condition of the autonomic penile nerves. The relationship between autonomic neuropathy and impotence in diabetes was studied in human corporeal tissue obtained during implantation of a penile prosthesis in 19 impotent diabetic and 15 nondiabetic patients. The functional status of penile cholinergic nerves was assessed by determining their ability to accumulate tritiated choline (34), and synthesize (34) and release (19) tritiated-acetylcholine after incubation of corporeal tissue with tritiated-choline (34). Tritiated-choline accumulation, and tritiated-acetylcholine synthesis and release were significantly reduced in the corporeal tissue from diabetic patients compared to thatmore » from nondiabetic patients (p less than 0.05). The impairment in acetylcholine synthesis worsened with the duration of diabetes (p less than 0.025). No differences in the parameters measured were found between insulin-dependent (11) and noninsulin-dependent (8) diabetic patients. The ability of the cholinergic nerves to synthesize acetylcholine could not be predicted clinically with sensory vibration perception threshold testing. It is concluded that there is a functional penile neuropathic condition of the cholinergic nerves in the corpus cavernosum of diabetic impotent patients that may be responsible for the erectile dysfunction.« less

The influence of a constraint and bimanual training program using a variety of modalities on endurance and on the cardiac autonomic regulation system of children with unilateral cerebral palsy: A self-control clinical trial.

PubMed

Cohen-Holzer, Marilyn; Sorek, Gilad; Schweizer, Maayan; Katz-Leurer, Michal

2017-01-01

An intensive hybrid program, combining constraint with bimanual training, improves upper extremity function as well as walking endurance of children with unilateral cerebral palsy (UCP). Endurance improvement may be associated with the cardiac autonomic regulation system (CARS) adaptation, known to be impaired among these children. To examine the influence of an intensive hybrid program on CARS, walking endurance and the correlation with upper extremity function of children with UCP. Twenty-four children aged 6-10 years with UCP participated in a hybrid program, 10 days, 6 hours per day. Data were collected pre-, post- and 3-months post-intervention. Main outcome measures included the Polar RS800CX for heart rate (HR) and heart rate variability (HRV) data, the 6-Minute Walk Test (6MWT) for endurance, and the Assisting Hand Assessment (AHA) and Jebsen-Taylor Test of Hand Function (JTTHF) for bimanual and unimanual function. A significant reduction in HR and an increase in HRV at post- and 3-month post-intervention was noted (χ22= 8.3, p = 0.016) along with a significant increase in 6MWT with a median increase of 81 meters (χ22= 11.0, p = 0.004) at the same interval. A significant improvement was noted in unimanual and bimanual performance following the intervention. An intensive hybrid program effectively improved CARS function as well as walking endurance and upper extremity function in children with UCP (213).

Tele-assistance for semi-autonomous robots

NASA Technical Reports Server (NTRS)

Rogers, Erika; Murphy, Robin R.

1994-01-01

This paper describes a new approach in semi-autonomous mobile robots. In this approach the robot has sufficient computerized intelligence to function autonomously under a certain set of conditions, while the local system is a cooperative decision making unit that combines human and machine intelligence. Communication is then allowed to take place in a common mode and in a common language. A number of exception-handling scenarios that were constructed as a result of experiments with actual sensor data collected from two mobile robots were presented.

Autonomous and Autonomic Systems: A Paradigm for Future Space Exploration Missions

NASA Technical Reports Server (NTRS)

Truszkowski, Walter F.; Hinchey, Michael G.; Rash, James L.; Rouff, Christopher A.

2004-01-01

NASA increasingly will rely on autonomous systems concepts, not only in the mission control centers on the ground, but also on spacecraft and on rovers and other assets on extraterrestrial bodies. Automomy enables not only reduced operations costs, But also adaptable goal-driven functionality of mission systems. Space missions lacking autonomy will be unable to achieve the full range of advanced mission objectives, given that human control under dynamic environmental conditions will not be feasible due, in part, to the unavoidably high signal propagation latency and constrained data rates of mission communications links. While autonomy cost-effectively supports accomplishment of mission goals, autonomicity supports survivability of remote mission assets, especially when human tending is not feasible. Autonomic system properties (which ensure self-configuring, self-optimizing self-healing, and self-protecting behavior) conceptually may enable space missions of a higher order into any previously flown. Analysis of two NASA agent-based systems previously prototyped, and of a proposed future mission involving numerous cooperating spacecraft, illustrates how autonomous and autonomic system concepts may be brought to bear on future space missions.

Microcapsule-based techniques for improving the safety of lithium-ion batteries

NASA Astrophysics Data System (ADS)

Baginska, Marta

Lithium-ion batteries are vital energy storage devices due to their high specific energy density, lack of memory effect, and long cycle life. While they are predominantly used in small consumer electronics, new strategies for improving battery safety and lifetime are critical to the successful implementation of high-capacity, fast-charging materials required for advanced Li-ion battery applications. Currently, the presence of a volatile, combustible electrolyte and an oxidizing agent (Lithium oxide cathodes) make the Li-ion cell susceptible to fire and explosions. Thermal overheating, electrical overcharging, or mechanical damage can trigger thermal runaway, and if left unchecked, combustion of battery materials. To improve battery safety, autonomic, thermally-induced shutdown of Li-ion batteries is demonstrated by depositing thermoresponsive polymer microspheres onto battery anodes. When the internal temperature of the cell reaches a critical value, the microspheres melt and conformally coat the anode and/or separator with an ion insulating barrier, halting Li-ion transport and shutting down the cell permanently. Charge and discharge capacity is measured for Li-ion coin cells containing microsphere-coated anodes or separators as a function of capsule coverage. Scanning electron microscopy images of electrode surfaces from cells that have undergone autonomic shutdown provides evidence of melting, wetting, and re-solidification of polyethylene (PE) into the anode and polymer film formation at the anode/separator interface. As an extension of this autonomic shutdown approach, a particle-based separator capable of performing autonomic shutdown, but which reduces the shorting hazard posed by current bi- and tri-polymer commercial separators, is presented. This dual-particle separator is composed of hollow glass microspheres acting as a physical spacer between electrodes, and PE microspheres to impart autonomic shutdown functionality. An oil-immersion technique is developed to simulate an overheating condition while the cell is cycling. Experimental protocols are developed to assess the performance of the separator in terms of its ability to perform autonomic shutdown and examine tested battery materials using scanning electron microscopy. Another approach to improving battery functionality is via the microencapsulation of battery additives. Currently, additives are added directly into a battery electrolyte, and while they typically perform their function given a sufficient loading, these additives often do so at the expense of battery performance. Microencapsulation allows for a high loading of additives to be incorporated into the cell and their release triggered only when and where they are needed. In this work, microencapsulation techniques are developed to successfully encapsulate 3-hexylthiophene, a stabilizing agent for high-voltage cathodes in Li-ion batteries and conductive polymer precursor, as well as the flame retardant Tris(2-choloroethyl phosphate) (TCP). Microcapsules containing 3-hexylthiophene are coated onto model battery electrodes and immersed in electrolyte. The microcapsule shell wall insulates the 3-hexylthiophene until the microcapsules are mechanically crushed and electropolymerization of the released core to form poly(3-ht) occurs under cyclic voltammetry. In addition, TCP was encapsulated using in situ polymerization. TCP-containing microcapsules are stable in electrolyte at room temperature, but are thermally triggered to release their payload at elevated temperatures. Experimental protocols are developed to study the in situ triggering and release of microencapsulated additives.

Functional evaluation of peripheral nerve regeneration and target reinnervation in animal models: a critical overview.

PubMed

Navarro, Xavier

2016-02-01

Peripheral nerve injuries usually lead to severe loss of motor, sensory and autonomic functions in the patients. Due to the complex requirements for adequate axonal regeneration, functional recovery is often poorly achieved. Experimental models are useful to investigate the mechanisms related to axonal regeneration and tissue reinnervation, and to test new therapeutic strategies to improve functional recovery. Therefore, objective and reliable evaluation methods should be applied for the assessment of regeneration and function restitution after nerve injury in animal models. This review gives an overview of the most useful methods to assess nerve regeneration, target reinnervation and recovery of complex sensory and motor functions, their values and limitations. The selection of methods has to be adequate to the main objective of the research study, either enhancement of axonal regeneration, improving regeneration and reinnervation of target organs by different types of nerve fibres, or increasing recovery of complex sensory and motor functions. It is generally recommended to use more than one functional method for each purpose, and also to perform morphological studies of the injured nerve and the reinnervated targets. © 2015 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

Differences in autonomic nerve function in patients with silent and symptomatic myocardial ischaemia.

PubMed Central

Shakespeare, C. F.; Katritsis, D.; Crowther, A.; Cooper, I. C.; Coltart, J. D.; Webb-Peploe, M. W.

1994-01-01

BACKGROUND--Autonomic neuropathy provides a mechanism for the absence of symptoms in silent myocardial ischaemia, but characterisation of the type of neuropathy is lacking. AIM--To characterise and compare autonomic nerve function in patients with silent and symptomatic myocardial ischaemia. METHODS AND RESULTS--The Valsalva manoeuvre, heart rate variation (HRV) in response to deep breathing and standing, lower body negative pressure, isometric handgrip, and the cold pressor test were performed by patients with silent (n = 25) and symptomatic (n = 25) ambulatory ischaemia and by controls (n = 21). No difference in parasympathetic efferent function between patients with silent and symptomatic ischaemia was recorded, but both had significantly less HRV in response to standing than the controls (p < 0.005 for silent and p < 0.01 for symptomatic). Patients with silent ischaemia showed an increased propensity for peripheral vasodilatation compared with symptomatic patients (p < 0.02) and controls (p < 0.04). Impaired sympathetic function was found in patients with pure silent ischaemia (n = 4) compared with the remaining patients with silent ischaemia whose pain pathways were presumed to be intact. CONCLUSIONS--Patients with silent ischaemia and pain pathways presumed to be intact have an enhanced peripheral vasodilator response, and if this applied to the coronary vasculature it could provide a mechanism for limiting ischaemia to below the pain threshold. Patients with pure silent ischaemia have evidence of sympathetic autonomic dysfunction. Images PMID:8297687

Anti-Collision Function Design and Performances of the CNES Formation Flying Experiment on the PRISMA Mission

NASA Technical Reports Server (NTRS)

Cayeux, P.; Raballand, F.; Borde, J.; Berges, J.-C.; Meyssignac, B.

2007-01-01

Within the framework of a partnership agreement, EADS ASTRIUM has worked since June 2006 for the CNES formation flying experiment on the PRISMA mission. EADS ASTRIUM is responsible for the anti-collision function. This responsibility covers the design and the development of the function as a Matlab/Simulink library, as well as its functional validation and performance assessment. PRISMA is a technology in-orbit testbed mission from the Swedish National Space Board, mainly devoted to formation flying demonstration. PRISMA is made of two micro-satellites that will be launched in 2009 on a quasi-circular SSO at about 700 km of altitude. The CNES FFIORD experiment embedded on PRISMA aims at flight validating an FFRF sensor designed for formation control, and assessing its performances, in preparation to future formation flying missions such as Simbol X; FFIORD aims as well at validating various typical autonomous rendezvous and formation guidance and control algorithms. This paper presents the principles of the collision avoidance function developed by EADS ASTRIUM for FFIORD; three kinds of maneuvers were implemented and are presented in this paper with their performances.

Preserved cardiac autonomic dynamics during sleep in subjects with spinal cord injuries.

PubMed

Tobaldini, Eleonora; Proserpio, Paola; Sambusida, Katrina; Lanza, Andrea; Redaelli, Tiziana; Frigerio, Pamela; Fratticci, Lara; Rosa, Silvia; Casali, Karina R; Somers, Virend K; Nobili, Lino; Montano, Nicola

2015-06-01

Spinal cord injuries (SCI) are associated with altered cardiovascular autonomic control (CAC). Sleep is characterized by modifications of autonomic control across sleep stages; however, no data are available in SCI subjects on CAC during sleep. We aim to assess cardiac autonomic modulation during sleep in subjects with SCI. 27 participants with a neurological and radiological diagnosis of cervical (Cerv, n = 12, ie, tetraplegic) and thoracic SCI (Thor, n = 15, ie, paraplegic) and healthy subjects (Controls) were enrolled. Overnight polysomnographic (PSG) recordings were obtained in all participants. Electrocardiography and respiration were extracted from PSG, divided into sleep stages [wakefulness (W), non-REM sleep (NREM) and REM] for assessment of CAC, using symbolic analysis (SA) and corrected conditional entropy (CCE). SA identified indices of sympathetic and parasympathetic modulation and CCE evaluated the degree of complexity of the heart period time series. SA revealed a reduction of sympathetic and predominant parasympathetic control during NREM compared to W and REM in SCI patients, independent of the level of the lesion, similar to the Controls. In all three groups, complexity of autonomic regulation was higher in NREM compared to W and REM. In subjects with SCI, cardiac autonomic control changed across sleep stages, with a reduction of sympathetic and an increase of parasympathetic modulation during NREM compared to W and REM, and a parallel increase of complexity during NREM, which was similar to the Controls. Cardiac autonomic dynamics during sleep are maintained in SCI, independent of the level of the lesion. Copyright © 2014 Elsevier B.V. All rights reserved.

Relative Navigation of Formation Flying Satellites

NASA Technical Reports Server (NTRS)

Long, Anne; Kelbel, David; Lee, Taesul; Leung, Dominic; Carpenter, Russell; Gramling, Cheryl; Bauer, Frank (Technical Monitor)

2002-01-01

The Guidance, Navigation, and Control Center (GNCC) at Goddard Space Flight Center (GSFC) has successfully developed high-accuracy autonomous satellite navigation systems using the National Aeronautics and Space Administration's (NASA's) space and ground communications systems and the Global Positioning System (GPS). In addition, an autonomous navigation system that uses celestial object sensor measurements is currently under development and has been successfully tested using real Sun and Earth horizon measurements.The GNCC has developed advanced spacecraft systems that provide autonomous navigation and control of formation flyers in near-Earth, high-Earth, and libration point orbits. To support this effort, the GNCC is assessing the relative navigation accuracy achievable for proposed formations using GPS, intersatellite crosslink, ground-to-satellite Doppler, and celestial object sensor measurements. This paper evaluates the performance of these relative navigation approaches for three proposed missions with two or more vehicles maintaining relatively tight formations. High-fidelity simulations were performed to quantify the absolute and relative navigation accuracy as a function of navigation algorithm and measurement type. Realistically-simulated measurements were processed using the extended Kalman filter implemented in the GPS Enhanced Inboard Navigation System (GEONS) flight software developed by GSFC GNCC. Solutions obtained by simultaneously estimating all satellites in the formation were compared with the results obtained using a simpler approach based on differencing independently estimated state vectors.

Fault Tolerance Analysis of L1 Adaptive Control System for Unmanned Aerial Vehicles

NASA Astrophysics Data System (ADS)

Krishnamoorthy, Kiruthika

Trajectory tracking is a critical element for the better functionality of autonomous vehicles. The main objective of this research study was to implement and analyze L1 adaptive control laws for autonomous flight under normal and upset flight conditions. The West Virginia University (WVU) Unmanned Aerial Vehicle flight simulation environment was used for this purpose. A comparison study between the L1 adaptive controller and a baseline conventional controller, which relies on position, proportional, and integral compensation, has been performed for a reduced size jet aircraft, the WVU YF-22. Special attention was given to the performance of the proposed control laws in the presence of abnormal conditions. The abnormal conditions considered are locked actuators (stabilator, aileron, and rudder) and excessive turbulence. Several levels of abnormal condition severity have been considered. The performance of the control laws was assessed over different-shape commanded trajectories. A set of comprehensive evaluation metrics was defined and used to analyze the performance of autonomous flight control laws in terms of control activity and trajectory tracking errors. The developed L1 adaptive control laws are supported by theoretical stability guarantees. The simulation results show that L1 adaptive output feedback controller achieves better trajectory tracking with lower level of control actuation as compared to the baseline linear controller under nominal and abnormal conditions.

Is heart rate variability associated with frequency and intensity of vasomotor symptoms among healthy perimenopausal and postmenopausal women?

PubMed

Jones, Salene M W; Guthrie, Katherine A; LaCroix, Andrea Z; Sternfeld, Barbara; Landis, Carol A; Reed, Susan D; Dunn, Andrea; Caan, Bette; Cohen, Lee S; Hunt, Julie; Newton, Katherine M

2016-02-01

Research has suggested that the autonomic nervous system (ANS) is involved in the experience of vasomotor symptoms (VMS) during menopause. We examined the relationship of VMS intensity and heart rate variability (HRV), a measure of ANS function. Women (n = 282) were recruited from three American states for a clinical trial of yoga, exercise, and omega-3 fatty acid supplements for VMS. To be eligible, women had to report at least 14 VMS per week, with some being moderate to severe. Sitting electrocardiograms were recorded for 15 min using Holter monitors at both baseline and 12-week follow-up. Time and frequency domain HRV measures were calculated. Women completed daily diary measures of VMS frequency and intensity for 2 weeks at baseline and for 1 week at the follow-up assessment 12 weeks later. Multivariable linear regression was used to assess the relationship between VMS and baseline HRV measures and to compare change in HRV with change in VMS over the 12 weeks. Baseline HRV was not associated with either VMS frequency or intensity at baseline. Change in HRV was not associated with change in VMS frequency or intensity across the follow-up. Heart rate variability (HRV) was not associated with basal VMS frequency or intensity in perimenopausal and postmenopausal women experiencing high levels of VMS. Autonomic function may be associated with the onset or presence of VMS, but not with the number or intensity of these symptoms.

Autonomy and Relatedness in Inner-City Families of Substance Abusing Adolescents

ERIC Educational Resources Information Center

Samuolis, Jessica; Hogue, Aaron; Dauber, Sarah; Liddle, Howard A.

2006-01-01

This study examined parent-adolescent autonomous-relatedness functioning in inner-city, ethnic minority families of adolescents exhibiting drug abuse and related problem behaviors. Seventy-four parent-adolescent dyads completed a structured interaction task prior to the start of treatment that was coded using an established autonomous-relatedness…

Subjective, Autonomic, and Endocrine Reactivity during Social Stress in Children with Social Phobia

ERIC Educational Resources Information Center

Kramer, Martina; Seefeldt, Wiebke Lina; Heinrichs, Nina; Tuschen-Caffier, Brunna; Schmitz, Julian; Wolf, Oliver Tobias; Blechert, Jens

2012-01-01

Reports of exaggerated anxiety and physiological hyperreactivity to social-evaluative situations are characteristic of childhood social phobia (SP). However, laboratory research on subjective, autonomic and endocrine functioning in childhood SP is scarce, inconsistent and limited by small sample sizes, limited breadth of measurements, and the use…

Autonomous Sensory Meridian Response (ASMR) and Frisson: Mindfully Induced Sensory Phenomena That Promote Happiness

ERIC Educational Resources Information Center

del Campo, Marisa A.; Kehle, Thomas J.

2016-01-01

There are many important phenomena involved in human functioning that are unnoticed, misunderstood, not applied, or do not pique the interest of the scientific community. Among these, "autonomous sensory meridian response" ("ASMR") and "frisson" are two very noteworthy instances that may prove to be therapeutically…

Implementation and Simulation Results using Autonomous Aerobraking Development Software

NASA Technical Reports Server (NTRS)

Maddock, Robert W.; DwyerCianciolo, Alicia M.; Bowes, Angela; Prince, Jill L. H.; Powell, Richard W.

2011-01-01

An Autonomous Aerobraking software system is currently under development with support from the NASA Engineering and Safety Center (NESC) that would move typically ground-based operations functions to onboard an aerobraking spacecraft, reducing mission risk and mission cost. The suite of software that will enable autonomous aerobraking is the Autonomous Aerobraking Development Software (AADS) and consists of an ephemeris model, onboard atmosphere estimator, temperature and loads prediction, and a maneuver calculation. The software calculates the maneuver time, magnitude and direction commands to maintain the spacecraft periapsis parameters within design structural load and/or thermal constraints. The AADS is currently tested in simulations at Mars, with plans to also evaluate feasibility and performance at Venus and Titan.

Automated Power Systems Management (APSM)

NASA Technical Reports Server (NTRS)

Bridgeforth, A. O.

1981-01-01

A breadboard power system incorporating autonomous functions of monitoring, fault detection and recovery, command and control was developed, tested and evaluated to demonstrate technology feasibility. Autonomous functions including switching of redundant power processing elements, individual load fault removal, and battery charge/discharge control were implemented by means of a distributed microcomputer system within the power subsystem. Three local microcomputers provide the monitoring, control and command function interfaces between the central power subsystem microcomputer and the power sources, power processing and power distribution elements. The central microcomputer is the interface between the local microcomputers and the spacecraft central computer or ground test equipment.

Sudden infant death syndrome: a cybernetic etiology.

PubMed

ben-Aaron, M

2003-01-01

The brain's processes, by hypothesis, involve information processing by an extraordinarily complex, highly sophisticated, self-organizing cybernetic system embedded in the central nervous system. This cybernetic system generates itself in successive stages. Breathing is, by default, an autonomous function, but breath control is learned. If there is not a smooth transfer of function at the time when a successor system (one that enables autonomous breathing to be overridden by voluntary control) takes over, breathing may cease, without any overt cause being detectable, even with a thorough postmortem examination. If conditions are such that, at that point, the infant's body lacks the strength to resume breathing again under autonomic control, Sudden Infant Death Syndrome may result. The theory explains why infants are at greater risk if they sleep face down.

Understanding Emotions in Frontotemporal Dementia: The Explicit and Implicit Emotional Cue Mismatch.

PubMed

Balconi, Michela; Cotelli, Maria; Brambilla, Michela; Manenti, Rosa; Cosseddu, Maura; Premi, Enrico; Gasparotti, Roberto; Zanetti, Orazio; Padovani, Alessandro; Borroni, Barbara

2015-01-01

Previous studies have reported significant deficits in emotion recognition among individuals along the frontotemporal dementia (FTD) spectrum. The basis of emotional impairment is still poorly understood and explicit (emotion appraisal) and implicit (autonomic system activity) responses have not been carefully evaluated. We investigated explicit evaluation of emotions by testing valence and arousal using self-report measures and we also assessed automatic responses to emotional cues, using autonomic measures (skin conductance response and heart rate). 16 behavioral variant FTD and 12 agrammatic variants of primary progressive aphasia patients were included. The performance of these patients was compared to a group of 14 patients with Alzheimer's disease and 20 healthy controls. Each subject was required to observe and evaluate affective pictures while autonomic parameters were recorded. FTD patients preserved a functional general competency in terms of valence (correct positive versus negative attribution) and arousal (correct dichotomy between high versus low arousal category) distinction. These patients showed significant changes in autonomic implicit response compared to the other groups. The mismatch between explicit and implicit responsiveness to emotional cues was found both in behavioral variant FTD and in agrammatic variants of primary progressive aphasia. Emotional responsiveness was related to the severity of behavioral abnormalities as measured by the Frontal Behavioral Inventory and associated with atrophy of the left putamen. The present findings indicate that FTD patients are able to explicitly "appraise" the emotion, but they cannot implicitly "feel" the emotion. This mismatch between the two levels may help explain the general emotional behavior impairment found in these patients.

Increased interarm blood pressure difference is associated with autonomic dysfunction and atherosclerosis in patients with chest pain and no history of coronary artery disease.

PubMed

Hwang, Hui-Jeong; Sohn, Il Suk; Kim, Dong-Hee; Park, Chang-Bum; Cho, Jin-Man; Kim, Chong-Jin

2017-08-15

Interarm blood pressure (BP) difference has been reported to be associated with atherosclerosis and increased cardiovascular death. We were to investigate associations of interarm systolic blood pressure (SBP) difference with heart rate recovery (HRR) after exercise, an index of autonomic function, and carotid atherosclerotic markers, and to evaluate the association of interarm SBP difference with concurrent coronary artery disease (CAD). A total of 995 consecutive patients who underwent treadmill stress echocardiography with chest pain but no history of CAD were enrolled. Interarm SBP difference, carotid intima-media thickness (IMT) and plaque were measured before exercise, and HRR 2min following exercise was assessed. Suspected CAD was defined as newly developed wall motion abnormalities after treadmill exercise. Patients with an interarm SBP difference≥10mmHg had higher prevalence of hypertension, increased right and left SBP, right diastolic BP, mean arterial pressure, body mass index and carotid IMT, existent carotid plaque, lower metabolic equivalents and slower HRR. Interarm SBP difference≥10mmHg was independently associated with slower HRR and existent carotid plaque. Suspected CAD was associated with existent carotid plaque or slower HRR, but not with an interarm SBP difference≥10mmHg. Increased interarm SBP difference was associated with lower autonomic modulation and carotid atherosclerosis in patients with chest pain and no history of CAD, but not with suspected CAD. Observed adverse prognosis in patients with increased interarm BP difference might result from long-term persistent autonomic dysfunction and atherosclerosis. Copyright © 2017 Elsevier B.V. All rights reserved.

The relation of autonomic function to physical fitness in patients suffering from alcohol dependence.

PubMed

Herbsleb, Marco; Schulz, Steffen; Ostermann, Stephanie; Donath, Lars; Eisenträger, Daniela; Puta, Christian; Voss, Andreas; Gabriel, Holger W; Bär, Karl-Jürgen

2013-10-01

Reduced cardio-vascular health has been found in patients suffering from alcohol dependence. Low cardio-respiratory fitness is an independent predictor of cardio-vascular disease. We investigated physical fitness in 22 alcohol-dependent patients 10 days after acute alcohol withdrawal and compared results with matched controls. The standardized 6-min walk test (6 MWT) was used to analyze the relationship of autonomic dysfunction and physical fitness. Ventilatory indices and gas exchanges were assessed using a portable spiroergometric system while heart rate recordings were obtained separately. We calculated walking distance, indices of heart rate variability and efficiency parameters of heart rate and breathing. In addition, levels of exhaled carbon monoxide were measured in all participants to account for differences in smoking behaviour. Multivariate analyses of variance (MANOVA) were performed to investigate differences between patients and controls with regard to autonomic and efficiency parameters. Patients walked a significantly shorter distance in comparison to healthy subjects during the 6 MWT. Significantly decreased heart rate variability was observed before and after the test in patients when compared to controls, while no such difference was observed during exercise. The efficiency parameters indicated significantly reduced efficiency in physiological regulation when the obtained parameters were normalized to the distance. The 6 MWT is an easily applied instrument to measure physical fitness in alcohol dependent patients. It can also be used during exercise interventions. Reduced physical fitness, as observed in our study, might partly be caused by autonomic dysfunction, leading to less efficient regulation of physiological processes during exercise. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Comparison of the effect of valsartan and lisinopril on autonomic nervous system activity in chronic heart failure.

PubMed

De Tommasi, Elisabetta; Iacoviello, Massimo; Romito, Roberta; Ceconi, Claudio; Guida, Pietro; Massari, Francesco; Francolini, Gloria; Bertocchi, Federico; Ferrari, Roberto; Rizzon, Paolo; Pitzalis, Maria Vittoria

2003-11-01

In chronic heart failure (CHF), the derangement of autonomic nervous system activity has a deep impact on the progression of the disease. It has been demonstrated that modulation of the renin-angiotensin aldosterone system (RAAS) increases autonomic control of heart rate and reduces adrenergic activity. We sought to evaluate, in CHF, the different effects of an ACE inhibitor (lisinopril) and of an AT1 receptor antagonist (valsartan) on heart rate variability, baroreflex sensitivity and norepinephrine plasma levels. Ninety patients (61 +/- 10 years, 2.3 +/- 0.5, New York Heart Association class) with CHF and left ventricular ejection fraction <40% were randomly assigned in a double-blind fashion to receive lisinopril (uptitrated to 20 mg/d) or valsartan (uptitrated to 160 mg/d) therapy for 16 weeks. Heart rate variability (evaluated by measuring standard deviation of normal R-R intervals on 24-hour ECG recordings), spontaneous baroreflex sensitivity and aldosterone and norepinephrine plasma levels were assessed before and after drug therapy. There were no significant differences between valsartan and lisinopril in their effects on left ventricular function, arterial pressure, aldosterone plasma levels and autonomic control of heart rate. Both lisinopril and valsartan significantly reduced plasma norepinephrine levels, but the reduction induced by valsartan was significantly greater than that observed for lisinopril (27% vs 6%, P <.05). This study shows a comparable effect of ACE inhibition (lisinopril) and of AT1 receptor antagonism (valsartan) on cardiac vagal control of heart rate, whereas valsartan has shown a more effective modulation of sympathetic activity measured by plasma norepinephrine levels.

Biological stress systems, adverse life events and the onset of chronic multisite musculoskeletal pain: a 6-year cohort study.

PubMed

Generaal, Ellen; Vogelzangs, Nicole; Macfarlane, Gary J; Geenen, Rinie; Smit, Johannes H; de Geus, Eco J C N; Penninx, Brenda W J H; Dekker, Joost

2016-05-01

Dysregulated biological stress systems and adverse life events, independently and in interaction, have been hypothesised to initiate chronic pain. We examine whether (1) function of biological stress systems, (2) adverse life events, and (3) their combination predict the onset of chronic multisite musculoskeletal pain. Subjects (n=2039) of the Netherlands Study of Depression and Anxiety, free from chronic multisite musculoskeletal pain at baseline, were identified using the Chronic Pain Grade Questionnaire and followed up for the onset of chronic multisite musculoskeletal pain over 6 years. Baseline assessment of biological stress systems comprised function of the hypothalamic-pituitary-adrenal axis (1-h cortisol awakening response, evening levels, postdexamethasone levels), the immune system (basal and lipopolysaccharide-stimulated inflammation) and the autonomic nervous system (heart rate, pre-ejection period, SD of the normal-to-normal interval, respiratory sinus arrhythmia). The number of recent adverse life events was assessed at baseline using the List of Threatening Events Questionnaire. Hypothalamic-pituitary-adrenal axis, immune system and autonomic nervous system functioning was not associated with onset of chronic multisite musculoskeletal pain, either by itself or in interaction with adverse life events. Adverse life events did predict onset of chronic multisite musculoskeletal pain (HR per event=1.14, 95% CI 1.04 to 1.24, p=0.005). This longitudinal study could not confirm that dysregulated biological stress systems increase the risk of developing chronic multisite musculoskeletal pain. Adverse life events were a risk factor for the onset of chronic multisite musculoskeletal pain, suggesting that psychosocial factors play a role in triggering the development of this condition. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Relationships between Rapid Eye Movement Sleep Behavior Disorder and Neurodegenerative Diseases: Clinical Assessments, Biomarkers, and Treatment

PubMed Central

Li, Min; Wang, Li; Liu, Jiang-Hong; Zhan, Shu-Qin

2018-01-01

Objective: Rapid eye movement sleep behavior disorder (RBD) is characterized by dream enactment and loss of muscle atonia during rapid eye movement sleep. RBD is closely related to α-synucleinopathies including Parkinson's disease, dementia with Lewy bodies, and multiple system atrophy. Many studies have investigated the markers of imaging and neurophysiological, genetic, cognitive, autonomic function of RBD and their predictive value for neurodegenerative diseases. This report reviewed the progress of these studies and discussed their limitations and future research directions. Data Sources: Using the combined keywords: “RBD”, “neurodegenerative disease”, “Parkinson disease”, and “magnetic resonance imaging”, the PubMed/MEDLINE literature search was conducted up to January 1, 2018. Study Selection: A total of 150 published articles were initially identified citations. Of the 150 articles, 92 articles were selected after further detailed review. This study referred to all the important English literature in full. Results: Single-nucleotide polymorphisms in SCARB2 (rs6812193) and MAPT (rs12185268) were significantly associated with RBD. The olfactory loss, autonomic dysfunction, marked electroencephalogram slowing during both wakefulness and rapid eye movement sleep, and cognitive impairments were potential predictive markers for RBD conversion to neurodegenerative diseases. Traditional structural imaging studies reported relatively inconsistent results, whereas reduced functional connectivity between the left putamen and substantia nigra and dopamine transporter uptake demonstrated by functional imaging techniques were relatively consistent findings. Conclusions: More longitudinal studies should be conducted to evaluate the predictive value of biomarkers of RBD. Moreover, because the glucose and dopamine metabolisms are not specific for assessing cognitive cognition, the molecular metabolism directly related to cognition should be investigated. There is a need for more treatment trials to determine the effectiveness of interventions of RBD on preventing the conversion to neurodegenerative diseases. PMID:29664058

Contrasting actions of pressor agents in severe autonomic failure

NASA Technical Reports Server (NTRS)

Jordan, J.; Shannon, J. R.; Biaggioni, I.; Norman, R.; Black, B. K.; Robertson, D.

1998-01-01

BACKGROUND: Orthostatic hypotension is the most disabling symptom of autonomic failure. The choice of a pressor agent is largely empiric, and it would be of great value to define predictors of a response. PATIENTS AND METHODS: In 35 patients with severe orthostatic hypotension due to multiple system atrophy or pure autonomic failure, we determined the effect on seated systolic blood pressure (SBP) of placebo, phenylpropanolamine (12.5 mg and 25 mg), yohimbine (5.4 mg), indomethacin (50 mg), ibuprofen (600 mg), caffeine (250 mg), and methylphenidate (5 mg). In a subgroup of patients, we compared the pressor effect of midodrine (5 mg) with the effect of phenylpropanolamine (12.5 mg). RESULTS: There were no significant differences in the pressor responses between patients with multiple system atrophy or pure autonomic failure. When compared with placebo, the pressor response was significant for phenylpropanolamine, yohimbine, and indomethacin. In a subgroup of patients, we confirmed that this pressor effect of phenylpropanolamine, yohimbine, and indomethacin corresponded to a significant increase in standing SBP. The pressor responses to ibuprofen, caffeine, and methylphenidate were not significantly different from placebo. Phenylpropanolamine and midodrine elicited similar pressor responses. There were no significant associations between drug response and autonomic function testing, postprandial hypotension, or plasma catecholamine levels. CONCLUSIONS: We conclude that significant increases in systolic blood pressure can be obtained in patients with orthostatic hypotension due to primary autonomic failure with phenylpropanolamine in low doses or yohimbine or indomethacin in moderate doses. The response to a pressor agent cannot be predicted by autonomic function testing or plasma catecholamines. Therefore, empiric testing with a sequence of medications, based on the risk of side effects in the individual patient and the probability of a response, is a useful approach.

Recurrent myocardial infarction: Mechanisms of free-floating adaptation and autonomic derangement in networked cardiac neural control.

PubMed

Kember, Guy; Ardell, Jeffrey L; Shivkumar, Kalyanam; Armour, J Andrew

2017-01-01

The cardiac nervous system continuously controls cardiac function whether or not pathology is present. While myocardial infarction typically has a major and catastrophic impact, population studies have shown that longer-term risk for recurrent myocardial infarction and the related potential for sudden cardiac death depends mainly upon standard atherosclerotic variables and autonomic nervous system maladaptations. Investigative neurocardiology has demonstrated that autonomic control of cardiac function includes local circuit neurons for networked control within the peripheral nervous system. The structural and adaptive characteristics of such networked interactions define the dynamics and a new normal for cardiac control that results in the aftermath of recurrent myocardial infarction and/or unstable angina that may or may not precipitate autonomic derangement. These features are explored here via a mathematical model of cardiac regulation. A main observation is that the control environment during pathology is an extrapolation to a setting outside prior experience. Although global bounds guarantee stability, the resulting closed-loop dynamics exhibited while the network adapts during pathology are aptly described as 'free-floating' in order to emphasize their dependence upon details of the network structure. The totality of the results provide a mechanistic reasoning that validates the clinical practice of reducing sympathetic efferent neuronal tone while aggressively targeting autonomic derangement in the treatment of ischemic heart disease.

Role of training and detraining on inflammatory and metabolic profile in infarcted rats: influences of cardiovascular autonomic nervous system.

PubMed

Rodrigues, Bruno; Santana, Aline Alves; Santamarina, Aline Boveto; Oyama, Lila Missae; Caperuto, Érico Chagas; de Souza, Cláudio Teodoro; Barboza, Catarina de Andrade; Rocha, Leandro Yanase; Figueroa, Diego; Mostarda, Cristiano; Irigoyen, Maria Cláudia; Lira, Fábio Santos

2014-01-01

The aim of this study was to evaluate the effects of exercise training (ET, 50-70% of VO2 max, 5 days/week) and detraining (DT) on inflammatory and metabolic profile after myocardial infarction (MI) in rats. Male Wistar rats were divided into control (C, n = 8), sedentary infarcted (SI, n = 9), trained infarcted (TI, n = 10; 3 months of ET), and detrained infarcted (DI, n = 11; 2 months of ET + 1 month of DT). After ET and DT protocols, ventricular function and inflammation, cardiovascular autonomic modulation (spectral analysis), and adipose tissue inflammation and lipolytic pathway were evaluated. ET after MI improved cardiac and vascular autonomic modulation, and these benefits were correlated with reduced inflammatory cytokines on the heart and adipose tissue. These positive changes were sustained even after 1 month of detraining. No expressive changes were observed in oxidative stress and lipolytic pathway in experimental groups. In conclusion, our results strongly suggest that the autonomic improvement promoted by ET, and maintained even after the detraining period, was associated with reduced inflammatory profile in the left ventricle and adipose tissue of rats subjected to MI. These data encourage enhancing cardiovascular autonomic function as a therapeutic strategy for the treatment of inflammatory process triggered by MI.

Role of Training and Detraining on Inflammatory and Metabolic Profile in Infarcted Rats: Influences of Cardiovascular Autonomic Nervous System

PubMed Central

Santana, Aline Alves; Santamarina, Aline Boveto; Oyama, Lila Missae; Caperuto, Érico Chagas; de Souza, Cláudio Teodoro; Barboza, Catarina de Andrade; Rocha, Leandro Yanase; Figueroa, Diego; Mostarda, Cristiano; Irigoyen, Maria Cláudia; Lira, Fábio Santos

2014-01-01

The aim of this study was to evaluate the effects of exercise training (ET, 50–70% of VO2 max, 5 days/week) and detraining (DT) on inflammatory and metabolic profile after myocardial infarction (MI) in rats. Male Wistar rats were divided into control (C, n = 8), sedentary infarcted (SI, n = 9), trained infarcted (TI, n = 10; 3 months of ET), and detrained infarcted (DI, n = 11; 2 months of ET + 1 month of DT). After ET and DT protocols, ventricular function and inflammation, cardiovascular autonomic modulation (spectral analysis), and adipose tissue inflammation and lipolytic pathway were evaluated. ET after MI improved cardiac and vascular autonomic modulation, and these benefits were correlated with reduced inflammatory cytokines on the heart and adipose tissue. These positive changes were sustained even after 1 month of detraining. No expressive changes were observed in oxidative stress and lipolytic pathway in experimental groups. In conclusion, our results strongly suggest that the autonomic improvement promoted by ET, and maintained even after the detraining period, was associated with reduced inflammatory profile in the left ventricle and adipose tissue of rats subjected to MI. These data encourage enhancing cardiovascular autonomic function as a therapeutic strategy for the treatment of inflammatory process triggered by MI. PMID:25045207

Autonomic nervous system and lipid metabolism: findings in anxious-depressive spectrum and eating disorders.

PubMed

Pistorio, Elisabetta; Luca, Maria; Luca, Antonina; Messina, Vincenzo; Calandra, Carmela

2011-10-28

To correlate lipid metabolism and autonomic dysfunction with anxious-depressive spectrum and eating disorders. To propose the lipid index (LI) as a new possible biomarker. 95 patients and 60 controls were enrolled from the University Psychiatry Unit of Catania and from general practitioners (GPs). The patients were divided into four pathological groups: Anxiety, Depression, Anxious-Depressive Disorder and Eating Disorders [Diagnostic and Statistical Manual of Mental Disorders Fourth Edition Text Revision (DSM-IV-TR) official/appendix criteria]. The levels of the cholesterol, triglycerides and apolipoproteins A and B were determined. The LI, for each subject, was obtained through a mathematical operation on the values of the cholesterol and triglycerides levels compared with the maximum cut-off of the general population. The autonomic functioning was tested with Ewing battery tests. Particularly, the correlation between heart rate variability (HRV) and lipid metabolism has been investigated. Pathological and control groups, compared among each other, presented some peculiarities in the lipid metabolism and the autonomic dysfunction scores. In addition, a statistically significant correlation has been found between HRV and lipid metabolism. Lipid metabolism and autonomic functioning seem to be related to the discussed psychiatric disorders. LI, in addition, could represent a new possible biomarker to be considered.

Motion planning for autonomous vehicle based on radial basis function neural network in unstructured environment.

PubMed

Chen, Jiajia; Zhao, Pan; Liang, Huawei; Mei, Tao

2014-09-18

The autonomous vehicle is an automated system equipped with features like environment perception, decision-making, motion planning, and control and execution technology. Navigating in an unstructured and complex environment is a huge challenge for autonomous vehicles, due to the irregular shape of road, the requirement of real-time planning, and the nonholonomic constraints of vehicle. This paper presents a motion planning method, based on the Radial Basis Function (RBF) neural network, to guide the autonomous vehicle in unstructured environments. The proposed algorithm extracts the drivable region from the perception grid map based on the global path, which is available in the road network. The sample points are randomly selected in the drivable region, and a gradient descent method is used to train the RBF network. The parameters of the motion-planning algorithm are verified through the simulation and experiment. It is observed that the proposed approach produces a flexible, smooth, and safe path that can fit any road shape. The method is implemented on autonomous vehicle and verified against many outdoor scenes; furthermore, a comparison of proposed method with the existing well-known Rapidly-exploring Random Tree (RRT) method is presented. The experimental results show that the proposed method is highly effective in planning the vehicle path and offers better motion quality.

Motion Planning for Autonomous Vehicle Based on Radial Basis Function Neural Network in Unstructured Environment

PubMed Central

Chen, Jiajia; Zhao, Pan; Liang, Huawei; Mei, Tao

2014-01-01

The autonomous vehicle is an automated system equipped with features like environment perception, decision-making, motion planning, and control and execution technology. Navigating in an unstructured and complex environment is a huge challenge for autonomous vehicles, due to the irregular shape of road, the requirement of real-time planning, and the nonholonomic constraints of vehicle. This paper presents a motion planning method, based on the Radial Basis Function (RBF) neural network, to guide the autonomous vehicle in unstructured environments. The proposed algorithm extracts the drivable region from the perception grid map based on the global path, which is available in the road network. The sample points are randomly selected in the drivable region, and a gradient descent method is used to train the RBF network. The parameters of the motion-planning algorithm are verified through the simulation and experiment. It is observed that the proposed approach produces a flexible, smooth, and safe path that can fit any road shape. The method is implemented on autonomous vehicle and verified against many outdoor scenes; furthermore, a comparison of proposed method with the existing well-known Rapidly-exploring Random Tree (RRT) method is presented. The experimental results show that the proposed method is highly effective in planning the vehicle path and offers better motion quality. PMID:25237902

Recent advances in orthostatic hypotension presenting orthostatic dizziness or vertigo.

PubMed

Kim, Hyun-Ah; Yi, Hyon-Ah; Lee, Hyung

2015-11-01

Orthostatic hypotension (OH), a proxy for sympathetic adrenergic failure, is the most incapacitating sign of autonomic failure. Orthostatic dizziness (OD) is known to be the most common symptom of OH. However, recent studies have demonstrated that 30-39 % of patients with OH experienced rotatory vertigo during upright posture (i.e., orthostatic vertigo, OV), which challenges the dogma that OH induces dizziness and not vertigo. A recent population-based study on spontaneously occurring OD across a wide age range showed that the one-year and lifetime prevalence of OD was 10.9 and 12.5 %, respectively. Approximately 83 % of patients with OD had at least one abnormal autonomic function test result. So far, 11 subtypes of OD have been proposed according to the pattern of autonomic dysfunction, and generalized autonomic failure of sympathetic adrenergic and parasympathetic cardiovagal functions was the most common type. Four different patterns of OH, such as classic, delayed, early, and transient type have been found in patients with OD. The head-up tilt test and Valsalva maneuver should be performed for a comprehensive evaluation of sympathetic adrenergic failure in patients with OD/OV. This review summarizes current advances in OH presenting OD/OV, with a particular focus on the autonomic dysfunction associated with OD.

Concurrent measurement of "real-world" stress and arousal in individuals with psychosis: assessing the feasibility and validity of a novel methodology.

PubMed

Kimhy, David; Delespaul, Philippe; Ahn, Hongshik; Cai, Shengnan; Shikhman, Marina; Lieberman, Jeffrey A; Malaspina, Dolores; Sloan, Richard P

2010-11-01

Psychosis has been repeatedly suggested to be affected by increases in stress and arousal. However, there is a dearth of evidence supporting the temporal link between stress, arousal, and psychosis during "real-world" functioning. This paucity of evidence may stem from limitations of current research methodologies. Our aim is to the test the feasibility and validity of a novel methodology designed to measure concurrent stress and arousal in individuals with psychosis during "real-world" daily functioning. Twenty patients with psychosis completed a 36-hour ambulatory assessment of stress and arousal. We used experience sampling method with palm computers to assess stress (10 times per day, 10 AM → 10 PM) along with concurrent ambulatory measurement of cardiac autonomic regulation using a Holter monitor. The clocks of the palm computer and Holter monitor were synchronized, allowing the temporal linking of the stress and arousal data. We used power spectral analysis to determine the parasympathetic contributions to autonomic regulation and sympathovagal balance during 5 minutes before and after each experience sample. Patients completed 79% of the experience samples (75% with a valid concurrent arousal data). Momentary increases in stress had inverse correlation with concurrent parasympathetic activity (ρ = -.27, P < .0001) and positive correlation with sympathovagal balance (ρ = .19, P = .0008). Stress and heart rate were not significantly related (ρ = -.05, P = .3875). The findings support the feasibility and validity of our methodology in individuals with psychosis. The methodology offers a novel way to study in high time resolution the concurrent, "real-world" interactions between stress, arousal, and psychosis. The authors discuss the methodology's potential applications and future research directions.

Non-motor symptoms and cardiac innervation in SYNJ1-related parkinsonism.

PubMed

De Rosa, A; Pellegrino, T; Pappatà, S; Lieto, M; Bonifati, V; Palma, V; Topa, A; Santoro, L; Bilo, L; Cuocolo, A; De Michele, G

2016-02-01

PARK20 is a rare autosomal recessive parkinsonism related to the SYNJ1 gene and characterized by early-onset of disease and atypical signs such as supranuclear vertical gaze palsy, dementia, dystonia, and generalized tonic-clonic seizures. Non-motor features and cardiac sympathetic innervation were assessed in two siblings affected by parkinsonism who harboured the homozygous Arg258Gln mutation in the SYNJ1 gene. The Non-Motor Symptoms, the SCOPA-AUT, the Mayo Sleep Questionnaires and polysomnography were used to investigate non-motor signs (NMS), autonomic dysfunction and REM Behavioural Disorder (RBD). Cognitive functions were examined by an extensive battery of neuropsychological tests. In addition, motor and sensory nerve conduction studies and evoked laser potentials were performed. Cardiac sympathetic innervation was assessed in the two patients by (123)I-metaiodobenzylguanidine (MIBG) scintigraphy, computing early and late heart-to-mediastinum (H/M) ratios and myocardial washout rates (WR). Among the non-motor symptoms and autonomic signs, case 1 had cold intolerance, drooling and dysphagia, while case 2 had pain and urinary dysfunction. Both cases showed mood and behavioural disorders. RBD were not found, whereas the neuropsychological assessment revealed a progressive cognitive impairment. Neurophysiological studies revealed no abnormalities. Indexes of cardiac sympathetic innervation in the two patients did not differ from those of control subjects. Our findings expand the phenotypic profile of SYNJ1-related parkinsonism. Preserved cardiac sympathetic function and absence of RBD suggest that PARK20 should be explained by a pathogenic mechanism different from Lewy Body pathology, or that the latter is not as widespread as idiopathic Parkinson's disease. Copyright © 2015 Elsevier Ltd. All rights reserved.

Affective brain areas and sleep disordered breathing

PubMed Central

Harper, Ronald M.; Kumar, Rajesh; Macey, Paul M.; Woo, Mary A.; Ogren, Jennifer A.

2014-01-01

The neural damage accompanying the hypoxia, reduced perfusion, and other consequences of sleep-disordered breathing found in obstructive sleep apnea, heart failure (HF), and congenital central hypoventilation syndrome (CCHS), appears in areas that serve multiple functions, including emotional drives to breathe, and involve systems that serve affective, cardiovascular, and breathing roles. The damage, assessed with structural magnetic resonance imaging (MRI) procedures, shows tissue loss or water content and diffusion changes indicative of injury, and impaired axonal integrity between structures; damage is preferentially unilateral. Functional MRI responses in affected areas also are time- or amplitude- distorted to ventilatory or autonomic challenges. Among the structures injured are the insular, cingulate, and ventral medial prefrontal cortices, as well as cerebellar deep nuclei and cortex, anterior hypothalamus, raphé, ventrolateral medulla, basal ganglia and, in CCHS, the locus coeruleus. Raphé and locus coeruleus injury may modify serotonergic and adrenergic modulation of upper airway and arousal characteristics. Since both axons and gray matter show injury, the consequences to function, especially to autonomic, cognitive, and mood regulation, are major. Several affected rostral sites, including the insular and cingulate cortices and hippocampus, mediate aspects of dyspnea, especially in CCHS, while others, including the anterior cingulate and thalamus, participate in initiation of inspiration after central breathing pauses, and the medullary injury can impair baroreflex and breathing control. The ancillary injury associated with sleep-disordered breathing to central structures can elicit multiple other distortions in cardiovascular, cognitive, and emotional functions in addition to effects on breathing regulation. PMID:24746053

Alterations in HPA-axis and autonomic nervous system functioning in childhood anxiety disorders point to a chronic stress hypothesis.

PubMed

Dieleman, Gwendolyn C; Huizink, Anja C; Tulen, Joke H M; Utens, Elisabeth M W J; Creemers, Hanneke E; van der Ende, Jan; Verhulst, Frank C

2015-01-01

It is of debate whether or not childhood anxiety disorders (AD) can be captured by one taxonomic construct. This study examined whether perceived arousal (PA), autonomic nervous system (ANS) and hypothalamic-pituitary-adrenal (HPA) axis measures can distinguish children with different primary diagnoses of clinical anxiety disorders (AD) from each other, and from a general population reference group (GP). The study sample consisted of 152 AD children (comparing separation anxiety disorder, generalized anxiety disorder, social phobia and specific phobia), aged 8- to 12-years, and 200 same-aged reference children. HPA-axis functioning was measured by a diurnal cortisol profile. ANS functioning was measured by continuous measures of skin conductance level in rest and during a mental arithmetic task and high frequency heart rate variability in rest. PA was assessed by a questionnaire. The AD sample showed lower high frequency heart rate variability during rest, heightened anticipatory PA, higher basal and reactive skin conductance levels and lower basal HPA-axis functioning compared to the GP sample. The existence of three or more clinical disorders, i.e. a high clinical 'load', was associated with lower basal HPA-axis functioning, higher skin conductance level and lower posttest PA. Specific phobia could be discerned from social phobia and separation anxiety disorder on higher skin conductance level. Our findings indicated that children with AD have specific psychophysiological characteristics, which resemble the psychophysiological characteristics of chronic stress. A high clinical 'load' is associated with an altered ANS and HPA-axis functioning. Overall, ANS and HPA-axis functioning relate to AD in general, accept for specific phobia. Copyright © 2014 Elsevier Ltd. All rights reserved.

System identification of closed-loop cardiovascular control mechanisms: diabetic autonomic neuropathy

NASA Technical Reports Server (NTRS)

Mukkamala, R.; Mathias, J. M.; Mullen, T. J.; Cohen, R. J.; Freeman, R.

1999-01-01

We applied cardiovascular system identification (CSI) to characterize closed-loop cardiovascular regulation in patients with diabetic autonomic neuropathy (DAN). The CSI method quantitatively analyzes beat-to-beat fluctuations in noninvasively measured heart rate, arterial blood pressure (ABP), and instantaneous lung volume (ILV) to characterize four physiological coupling mechanisms, two of which are autonomically mediated (the heart rate baroreflex and the coupling of respiration, measured in terms of ILV, to heart rate) and two of which are mechanically mediated (the coupling of ventricular contraction to the generation of the ABP wavelet and the coupling of respiration to ABP). We studied 37 control and 60 diabetic subjects who were classified as having minimal, moderate, or severe DAN on the basis of standard autonomic tests. The autonomically mediated couplings progressively decreased with increasing severity of DAN, whereas the mechanically mediated couplings were essentially unchanged. CSI identified differences between the minimal DAN and control groups, which were indistinguishable based on the standard autonomic tests. CSI may provide a powerful tool for assessing DAN.

Abnormal cardiac autonomic control in sickle cell disease following transient hypoxia.

PubMed

Sangkatumvong, Suvimol; Khoo, Michael C K; Coates, Thomas D

2008-01-01

Abnormalities in autonomic control in sickle cell anemia (SCA) patients have been reported by multiple researchers. However their potential causal association with sickle cell crisis remains unknown. We employed hypoxia, a known trigger to sickle cell crisis, to perturb the autonomic systems of the subjects. Cardiac autonomic control was non-invasively assessed by tracking the changes in heart rate variability (HRV) that occur following brief exposure to a hypoxia stimulus. Time varying spectral analysis of HRV was applied to estimate the cardiac autonomic response to the transient episode of hypoxia. The results demonstrate that cardiovascular autonomic response to hypoxia is substantially more sensitive in SCA than in normal controls. We also developed a model to compensate for the confounding effects of respiration on the HRV spectral indices by using the corresponding respiration signal to compensate for the respiratory correlated part of the HRV. This technique improved the resolution with which the effect of hypoxia on changes in HRV could be measured.

Hypersonic Research Vehicle (HRV) real-time flight test support feasibility and requirements study. Part 2: Remote computation support for flight systems functions

NASA Technical Reports Server (NTRS)

Rediess, Herman A.; Hewett, M. D.

1991-01-01

The requirements are assessed for the use of remote computation to support HRV flight testing. First, remote computational requirements were developed to support functions that will eventually be performed onboard operational vehicles of this type. These functions which either cannot be performed onboard in the time frame of initial HRV flight test programs because the technology of airborne computers will not be sufficiently advanced to support the computational loads required, or it is not desirable to perform the functions onboard in the flight test program for other reasons. Second, remote computational support either required or highly desirable to conduct flight testing itself was addressed. The use is proposed of an Automated Flight Management System which is described in conceptual detail. Third, autonomous operations is discussed and finally, unmanned operations.

The prognostic value of heart rate variability in the elderly, changing the perspective: from sympathovagal balance to chaos theory.

PubMed

Nicolini, Paola; Ciulla, Michele M; De Asmundis, Carlo; Magrini, Fabio; Brugada, Pedro

2012-05-01

Heart rate variability (HRV) is the temporal beat-to-beat variation in successive RR intervals on an electrocardiographic (ECG) recording and it reflects the regulation of the heart rate (HR) by the autonomic nervous system (ANS). HRV analysis is a noninvasive tool for the assessment of autonomic function that gained momentum in the late 1980s when its clinical relevance as a predictor of mortality was established by a milestone study by Kleiger et al. in patients with postacute myocardial infarction. In the last few decades, the increasing availability of commercial ECG devices offering HRV analysis has made HRV a favorite marker for risk stratification in the setting of cardiovascular disease. The rapid aging of the world population and the growing popularity of HRV have also fueled interest for the prognostic value of HRV in the elderly, outside a specific cardiological context. However, the discussion of HRV measures in the elderly is still very much centered on the rather reductionistic model of sympathovagal balance, with the orthosympathetic and parasympathetic limbs of the ANS exercising opposing effects on the heart via autonomic tone. The expanding application of nonlinear dynamics to medicine has brought to the forefront the notion of system complexity, embedded in the mathematical concepts of chaos theory and fractals, and provides an opportunity to suggest a broader interpretation for the prognostic significance of HRV, especially in the elderly. Although the use of novel indices of HRV may be hampered by practical issues, a more holistic approach to HRV may still be safeguarded if traditional time- and frequency-domain measures are viewed in terms of autonomic modulation. This review focuses on HRV in geriatric populations. It considers studies on the prognostic value of HRV in elderly subjects, discussing the potential confounding effect of erratic rhythm, and concentrates on the conceptual distinction between autonomic tone and autonomic modulation. It also briefly addresses the question of the practicality of ECG recordings and identifies a promising area for future research in the effects of common noncardioactive drugs on HRV. ©2012, The Authors. Journal compilation ©2012 Wiley Periodicals, Inc.

Relationships between health literacy, motivation and diet and physical activity in people with type 2 diabetes participating in peer-led support groups.

PubMed

Juul, Lise; Rowlands, Gill; Maindal, Helle Terkildsen

2018-03-17

To investigate associations between health literacy (HL) and diet and physical activity, and motivation and diet and physical activity in Danish people with type 2 diabetes. We used a cross-sectional design including 194 individuals with type 2 diabetes participating in peer-led support groups provided by the Danish Diabetes Association between January-December 2015. The participants completed a questionnaire at the first meeting including; The Summary of Diabetes Self-Care Activities (SDSCA) measure, The Treatment Self-Regulation Questionnaire (TSRQ) (Self-Determination Theory) measuring type of motivation, and two HL scales: The HLS-EU-Q16, and the Diabetes Health Literacy scale (Ishikawa, H). Data were analyzed using linear regression models adjusting for age, gender, educational level, diabetes duration, motivation and HL. The adjusted β (95%CI) showed that autonomous motivation and functional HL were associated with following recommended diet: autonomous motivation; 0.43 (0.06; 0.80) and functional HL; 0.52 (0.02; 1.00). Autonomous motivation was related to following physical activity recommendations; β (95%CI) 0.56 (0.16; 0.96). This study indicates that, for people with type 2 diabetes, functional HL and autonomous motivation may be important drivers for following diet recommendations, and autonomous motivation may be the most important factor for following recommendations regarding physical activity. These concepts may therefore be highly relevant to address in interventions to people with type 2 diabetes. Different interventions are suggested. Copyright © 2018 Primary Care Diabetes Europe. Published by Elsevier Ltd. All rights reserved.

Balance of autonomic nervous system in children having signs of endothelial dysfunction, that were born and are domiciled in contaminated territories.

PubMed

Kondrashova, V G; Kolpakov, I E; Vdovenko, V Yu; Leonovych, O S; Lytvynets, O M; Stepanova, E I

2014-09-01

Objective. The study examined the features of functional state of the autonomic nervous system in children having endothelial dysfunction and permanently residing in contaminated areas. Materials and methods. Clinical and instrumental examination of 101 children aged 7-18 years that were born and are domiciled in contaminated territories, including 37 persons with signs of endothelial dysfunction (subgroup IA) and 64 ones with no signs of endothelial dysfunction (IB subgroup) was conducted. The control group being comparable to the subgroups IA and IB by age, gender and clinical examination results included 37 children neither been domiciled in contaminated areas nor were belonging to the contingent of Chornobyl accident survivors. There were 20 apparently healthy children also examined. Results. Due to peculiarities of physiological pathways providing adaptive responses the children having signs of endothelial dysfunction are characterized by a more pronounced dysregulation of autonomous nervous system both in a resting state and under a functional load simulation, and also by a high strain of adaptation pathways. The lack of autonomous support of cardiovascular system is caused by inadequate adaptive responses of both central regulatory bodies (hypothalamus, vasomotor center) and peripheral receptors. Mainly the failure of segmental autonomous (parasympathetic) structures was revealed. The mode of their response to stress in this case corresponds to that in healthy individuals but at a lower functional level. There is a reduced aerobic capacity of the organism by the Robinson index, contributing to low adaptive range to non-specific stress in children being domiciled on contaminated territories including children having the endothelial dysfunction. Conclusions. Endothelial dysfunction was associated with more pronounced manifestations of autonomic dysregulation and reduced aerobic capacity of the organism being the risk factors of development of a range of somatic diseases requiring the development of prevention measures in children permanently residing in contaminated areas. autonomous nervous system balance, endothelial dysfunction, children, Chornobyl accident. V. G. Kondrashova, I. E. Kolpakov, V. Yu. Vdovenko, O. S. Leonovych, O. M. Lytvynets, E. I. Stepanova.

Global asymptotical ω-periodicity of a fractional-order non-autonomous neural networks.

PubMed

Chen, Boshan; Chen, Jiejie

2015-08-01

We study the global asymptotic ω-periodicity for a fractional-order non-autonomous neural networks. Firstly, based on the Caputo fractional-order derivative it is shown that ω-periodic or autonomous fractional-order neural networks cannot generate exactly ω-periodic signals. Next, by using the contraction mapping principle we discuss the existence and uniqueness of S-asymptotically ω-periodic solution for a class of fractional-order non-autonomous neural networks. Then by using a fractional-order differential and integral inequality technique, we study global Mittag-Leffler stability and global asymptotical periodicity of the fractional-order non-autonomous neural networks, which shows that all paths of the networks, starting from arbitrary points and responding to persistent, nonconstant ω-periodic external inputs, asymptotically converge to the same nonconstant ω-periodic function that may be not a solution. Copyright © 2015 Elsevier Ltd. All rights reserved.

Usability of Operational Performance Support Tools - Findings from Sea Test II

NASA Technical Reports Server (NTRS)

Byrne, Vicky; Litaker, Harry; McGuire, Kerry

2014-01-01

Sea Test II, aka NASA Extreme Environment Mission Operations 17(NEEMO 17) took place in the Florida Aquarius undersea habitat. This confined underwater environment provides a excellent analog for space habitation providing similarities to space habitation such as hostile environment, difficult logistics, autonomous operations, and remote communications. This study collected subjective feedback on the usability of two performance support tools during the Sea Test II mission, Sept 10-14, 2013; Google Glass and iPAD. The two main objectives: - Assess the overall functionality and usability of each performance support tool in a mission analog environment. - Assess the advantages and disadvantages of each tool when performing operational procedures and Just-In-Time-Training (JITT).

OAST Space Theme Workshop. Volume 3: Working group summary. 1: Navigation, guidance, control (E-1) A. Statement. B. Technology needs (form 1). C. Priority assessment (form 2)

NASA Technical Reports Server (NTRS)

1976-01-01

The six themes identified by the Workshop have many common navigation guidance and control needs. All the earth orbit themes have a strong requirement for attitude, figure and stabilization control of large space structures, a requirement not currently being supported. All but the space transportation theme have need for precision pointing of spacecraft and instruments. In addition all the themes have requirements for increasing autonomous operations for such activities as spacecraft and experiment operations, onboard mission modification, rendezvous and docking, spacecraft assembly and maintenance, navigation and guidance, and self-checkout, test and repair. Major new efforts are required to conceptualize new approaches to large space antennas and arrays that are lightweight, readily deployable, and capable of precise attitude and figure control. Conventional approaches offer little hope of meeting these requirements. Functions that can benefit from increasing automation or autonomous operations are listed.

Development of a new integrated local trajectory planning and tracking control framework for autonomous ground vehicles

NASA Astrophysics Data System (ADS)

Li, Xiaohui; Sun, Zhenping; Cao, Dongpu; Liu, Daxue; He, Hangen

2017-03-01

This study proposes a novel integrated local trajectory planning and tracking control (ILTPTC) framework for autonomous vehicles driving along a reference path with obstacles avoidance. For this ILTPTC framework, an efficient state-space sampling-based trajectory planning scheme is employed to smoothly follow the reference path. A model-based predictive path generation algorithm is applied to produce a set of smooth and kinematically-feasible paths connecting the initial state with the sampling terminal states. A velocity control law is then designed to assign a speed value at each of the points along the generated paths. An objective function considering both safety and comfort performance is carefully formulated for assessing the generated trajectories and selecting the optimal one. For accurately tracking the optimal trajectory while overcoming external disturbances and model uncertainties, a combined feedforward and feedback controller is developed. Both simulation analyses and vehicle testing are performed to verify the effectiveness of the proposed ILTPTC framework, and future research is also briefly discussed.

The Caenorhabditis elegans Ephrin EFN-4 Functions Non-cell Autonomously with Heparan Sulfate Proteoglycans to Promote Axon Outgrowth and Branching

PubMed Central

Schwieterman, Alicia A.; Steves, Alyse N.; Yee, Vivian; Donelson, Cory J.; Bentley, Melissa R.; Santorella, Elise M.; Mehlenbacher, Taylor V.; Pital, Aaron; Howard, Austin M.; Wilson, Melissa R.; Ereddia, Danielle E.; Effrein, Kelsie S.; McMurry, Jonathan L.; Ackley, Brian D.; Chisholm, Andrew D.; Hudson, Martin L.

2016-01-01

The Eph receptors and their cognate ephrin ligands play key roles in many aspects of nervous system development. These interactions typically occur within an individual tissue type, serving either to guide axons to their terminal targets or to define boundaries between the rhombomeres of the hindbrain. We have identified a novel role for the Caenorhabditis elegans ephrin EFN-4 in promoting primary neurite outgrowth in AIY interneurons and D-class motor neurons. Rescue experiments reveal that EFN-4 functions non-cell autonomously in the epidermis to promote primary neurite outgrowth. We also find that EFN-4 plays a role in promoting ectopic axon branching in a C. elegans model of X-linked Kallmann syndrome. In this context, EFN-4 functions non-cell autonomously in the body-wall muscle and in parallel with HS modification genes and HSPG core proteins. This is the first report of an epidermal ephrin providing a developmental cue to the nervous system. PMID:26645816

Autonomous navigation - The ARMMS concept. [Autonomous Redundancy and Maintenance Management Subsystem

NASA Technical Reports Server (NTRS)

Wood, L. J.; Jones, J. B.; Mease, K. D.; Kwok, J. H.; Goltz, G. L.; Kechichian, J. A.

1984-01-01

A conceptual design is outlined for the navigation subsystem of the Autonomous Redundancy and Maintenance Management Subsystem (ARMMS). The principal function of this navigation subsystem is to maintain the spacecraft over a specified equatorial longitude to within + or - 3 deg. In addition, the navigation subsystem must detect and correct internal faults. It comprises elements for a navigation executive and for orbit determination, trajectory, maneuver planning, and maneuver command. Each of these elements is described. The navigation subsystem is to be used in the DSCS III spacecraft.

Autonomous scheduling technology for Earth orbital missions

NASA Technical Reports Server (NTRS)

Srivastava, S.

1982-01-01

The development of a dynamic autonomous system (DYASS) of resources for the mission support of near-Earth NASA spacecraft is discussed and the current NASA space data system is described from a functional perspective. The future (late 80's and early 90's) NASA space data system is discussed. The DYASS concept, the autonomous process control, and the NASA space data system are introduced. Scheduling and related disciplines are surveyed. DYASS as a scheduling problem is also discussed. Artificial intelligence and knowledge representation is considered as well as the NUDGE system and the I-Space system.

The Functioning of Autonomous Colleges

ERIC Educational Resources Information Center

Rao, V. Pala Prasada; Rao, Digumarti Bhaskara

2012-01-01

The college gets separated from the university, though not completely, when it is an autonomous college, which is practice in India. Academic package will become flexible and the decision-making is internalized, changes and updating could be easily carried out, depending on the need as reflected from the feedback taken from alumni, user sectors,…

Normal Reactions to Orthostatic Stress in Rett Syndrome

ERIC Educational Resources Information Center

Larsson, Gunilla; Julu, Peter O. O.; Engerstrom, Ingegerd Witt; Sandlund, Marlene; Lindstrom, Britta

2013-01-01

The aim of this study was to investigate orthostatic reactions in females with Rett syndrome (RTT), and also whether the severity of the syndrome had an impact on autonomic reactions. Based on signs of impaired function of the central autonomic system found in RTT, it could be suspected that orthostatic reactions were affected. The orthostatic…

Heart rate variability in normal-weight patients with polycystic ovary syndrome.

PubMed

Kilit, Celal; Paşalı Kilit, Türkan

2017-05-01

Polycystic ovary syndrome (PCOS) is an endocrine disease closely related to several risk factors of cardiovascular disease. Obese women with PCOS show altered autonomic modulation. The results of studies investigating cardiac autonomic functions of normal-weight women with PCOS are conflicting. The aim of the study was to assess the reactivity of cardiac sympathovagal balance in normal-weight women with PCOS by heart rate variability analysis. We examined the heart rate variability in 60 normal-weight women with PCOS and compared them with that in 60 age-matched healthy women having a similar metabolic profile. Time and frequency domain parameters of heart rate variability were analyzed based on 5-min-long continuous electrocardiography recordings for the following 3 periods: (1) during rest in supine position, (2) during controlled breathing, and (3) during isometric handgrip exercise. Time and frequency domain parameters of heart rate variability for the 3 periods assessed were similar in the two groups. Although modified Ferriman-Gallwey score and serum testosterone and luteinizing hormone levels were significantly higher in women with PCOS, homeostatic model assessment-insulin resistance (HOMA-IR) was not different the between the PCOS and control groups. There were no significant correlations between serum testosterone levels and heart rate variability parameters among the study population. The findings of this study suggest that the reactivity of cardiac sympathovagal balance is not altered in normal-weight women with PCOS having a normal HOMA-IR.

Dissociated emergent-response system and fine-processing system in human neural network and a heuristic neural architecture for autonomous humanoid robots.

PubMed

Yan, Xiaodan

2010-01-01

The current study investigated the functional connectivity of the primary sensory system with resting state fMRI and applied such knowledge into the design of the neural architecture of autonomous humanoid robots. Correlation and Granger causality analyses were utilized to reveal the functional connectivity patterns. Dissociation was within the primary sensory system, in that the olfactory cortex and the somatosensory cortex were strongly connected to the amygdala whereas the visual cortex and the auditory cortex were strongly connected with the frontal cortex. The posterior cingulate cortex (PCC) and the anterior cingulate cortex (ACC) were found to maintain constant communication with the primary sensory system, the frontal cortex, and the amygdala. Such neural architecture inspired the design of dissociated emergent-response system and fine-processing system in autonomous humanoid robots, with separate processing units and another consolidation center to coordinate the two systems. Such design can help autonomous robots to detect and respond quickly to danger, so as to maintain their sustainability and independence.

Papillary thyroid carcinoma in an autonomous hyperfunctioning thyroid nodule: case report and review of the literature.

PubMed

Tfayli, Hala M; Teot, Lisa A; Indyk, Justin A; Witchel, Selma Feldman

2010-09-01

Whereas thyroid nodules are less common among children than among adults, the anxiety generated by the finding of a thyroid nodule is high because 20% of nodules found in children contain thyroid cancer. Discovery of a nodule in the context of hyperthyroidism is usually comforting due to the presumption that the nodule represents a benign toxic adenoma. An 11-year-old girl presented with heavy menses, fatigue, and a right thyroid mass. Laboratory evaluation revealed elevated triiodothyronine and undetectable thyroid-stimulating hormone. Thyroid ultrasonography revealed a 3.5 cm nonhomogenous nodule, and scintigraphy was consistent with an autonomous hyper-functioning nodule. Fine-needle aspiration biopsy could not rule out malignancy, and patient underwent right hemithyroidectomy and isthmusectomy. Pathology was consistent with papillary thyroid carcinoma. We report the discovery of papillary thyroid carcinoma in an autonomously hyperfunctioning nodule in an 11-year-old girl. Detection of an autonomously functioning thyroid nodule in children and adolescents does not exclude the possibility of thyroid carcinoma and warrants careful evaluation and appropriate therapy.

Papillary Thyroid Carcinoma in an Autonomous Hyperfunctioning Thyroid Nodule: Case Report and Review of the Literature

PubMed Central

Tfayli, Hala M.; Teot, Lisa A.; Indyk, Justin A.

2010-01-01

Background Whereas thyroid nodules are less common among children than among adults, the anxiety generated by the finding of a thyroid nodule is high because 20% of nodules found in children contain thyroid cancer. Discovery of a nodule in the context of hyperthyroidism is usually comforting due to the presumption that the nodule represents a benign toxic adenoma. Summary An 11-year-old girl presented with heavy menses, fatigue, and a right thyroid mass. Laboratory evaluation revealed elevated triiodothyronine and undetectable thyroid-stimulating hormone. Thyroid ultrasonography revealed a 3.5 cm nonhomogenous nodule, and scintigraphy was consistent with an autonomous hyper-functioning nodule. Fine-needle aspiration biopsy could not rule out malignancy, and patient underwent right hemithyroidectomy and isthmusectomy. Pathology was consistent with papillary thyroid carcinoma. Conclusions We report the discovery of papillary thyroid carcinoma in an autonomously hyperfunctioning nodule in an 11-year-old girl. Detection of an autonomously functioning thyroid nodule in children and adolescents does not exclude the possibility of thyroid carcinoma and warrants careful evaluation and appropriate therapy. PMID:20718686

Simulation and Control Lab Development for Power and Energy Management for NASA Manned Deep Space Missions

NASA Technical Reports Server (NTRS)

McNelis, Anne M.; Beach, Raymond F.; Soeder, James F.; McNelis, Nancy B.; May, Ryan; Dever, Timothy P.; Trase, Larry

2014-01-01

The development of distributed hierarchical and agent-based control systems will allow for reliable autonomous energy management and power distribution for on-orbit missions. Power is one of the most critical systems on board a space vehicle, requiring quick response time when a fault or emergency is identified. As NASAs missions with human presence extend beyond low earth orbit autonomous control of vehicle power systems will be necessary and will need to reliably function for long periods of time. In the design of autonomous electrical power control systems there is a need to dynamically simulate and verify the EPS controller functionality prior to use on-orbit. This paper presents the work at NASA Glenn Research Center in Cleveland, Ohio where the development of a controls laboratory is being completed that will be utilized to demonstrate advanced prototype EPS controllers for space, aeronautical and terrestrial applications. The control laboratory hardware, software and application of an autonomous controller for demonstration with the ISS electrical power system is the subject of this paper.

Gender differences in cardiac patients: a longitudinal investigation of exercise, autonomic anxiety, negative affect and depression.

PubMed

Hunt-Shanks, Tiffany; Blanchard, Christopher; Reid, Robert D

2009-05-01

Female cardiac patients frequently experience greater anxiety and depression and engage in less exercise when compared with their male counterparts. This study considered whether exercise had similar effects on male and female cardiac patients' autonomic anxiety, negative affect and depression, and whether exercise behavior explained the gender difference in their affective functioning (e.g. autonomic anxiety, negative affect and depression). Eight hundred one participants completed the Hospital and Anxiety Depression Scale (HADS) and the leisure score index (LSI) of the Godin Leisure-Time Exercise Questionnaire at baseline, 6 months, 12 months, and 24 months. Female cardiac patients had greater autonomic anxiety, negative affect and depression and reduced exercise when compared with male cardiac patients at all time points. Although exercise was significantly related to affective outcomes at various time points for both men and women, gender did not moderate any of the exercise/affective relationships, and exercise did not mediate any of the gender/affective relationships. Further research is needed to clarify the complex relationships between gender, exercise, and the affective functioning of cardiac patients.

A subclass of plant heat shock cognate 70 chaperones carries a motif that facilitates trafficking through plasmodesmata

PubMed Central

Aoki, Koh; Kragler, Friedrich; Xoconostle-Cázares, Beatriz; Lucas, William J.

2002-01-01

Plasmodesmata establish a pathway for the trafficking of non-cell-autonomously acting proteins and ribonucleoprotein complexes. Plasmodesmal enriched cell fractions and the contents of enucleate sieve elements, in the form of phloem sap, were used to isolate and characterize heat shock cognate 70 (Hsc70) chaperones associated with this cell-to-cell transport pathway. Three Cucurbita maxima Hsc70 chaperones were cloned and functional and sequence analysis led to the identification of a previously uncharacterized subclass of non-cell-autonomous chaperones. The highly conserved nature of the heat shock protein 70 (Hsp70) family, in conjunction with mutant analysis, permitted the characterization of a motif that allows these Hsc70 chaperones to engage the plasmodesmal non-cell-autonomous translocation machinery. Proof of concept that this motif is necessary for Hsp70 gain-of-movement function was obtained through the engineering of a human Hsp70 that acquired the capacity to traffic through plasmodesmata. These results are discussed in terms of the roles likely played by this subclass of Hsc70 chaperones in the trafficking of non-cell-autonomous proteins. PMID:12456884

An exploratory thermographic investigation of the effects of connective tissue massage on autonomic function.

PubMed

Holey, Liz A; Dixon, John; Selfe, James

2011-09-01

The purpose of this study was to measure effects of connective tissue massage (CTM) on the autonomic nervous system using thermography and physiological measurements. A repeated-measures design was used. The setting was a university laboratory. Skin temperature at the site of massage, blood pressure, heart rate, and dorsal foot temperature were measured in 8 healthy participants before CTM, immediately after, and at 15-minute intervals for 1 hour. The effect of CTM on skin temperature was statistically significant, P = .011. Post hoc pairwise comparisons revealed that the 15-, 30-, 45-, and 60-minute data all differed significantly from the pre-CTM data (all P < .05) and also from the immediately post-CTM data (all P < .05). For diastolic blood pressure, the main analysis of variance showed a statistical significance at P = .062. For other variables, there was no evidence for an effect. Evidence was seen of some effects of CTM on autonomic function. This is information that will increase our knowledge of how CTM affects the autonomic nervous system. Copyright © 2011 National University of Health Sciences. Published by Mosby, Inc. All rights reserved.

Association between autonomic dysfunction and fatigue in Parkinson disease.

PubMed

Chou, Kelvin L; Gilman, Sid; Bohnen, Nicolaas I

2017-06-15

Fatigue is a disabling non-motor symptom in Parkinson disease (PD). We investigated the relationship between autonomic dysfunction and fatigue in PD while accounting for possible confounding factors. 29 subjects with PD (8F/21M; mean age 61.6±5.9; mean disease duration 4.8±3.0years), underwent clinical assessment and completed several non-motor symptom questionnaires, including a modified version of the Mayo Clinic Composite Autonomic Symptom Score (COMPASS) scale and the Fatigue Severity Scale (FSS). The mean modified COMPASS was 21.6±14.2 (range 1.7-44.2) and the mean FSS score was 3.3±1.6 (range 1.0-6.7). There was a significant bivariate relationship between the modified COMPASS and FSS scores (R=0.69, P<0.0001). Stepwise regression analysis was used to assess the specificity of the association between the modified COMPASS and FSS scores while accounting for possible confounder effects from other variables that were significantly associated with autonomic dysfunction. Results showed that the modified COMPASS (R 2 =0.52, F=28.4, P<0.0001) was highly associated with fatigue, followed by ESS (R 2 =0.13, F=8.4, P=0.008) but no other co-variates. Post-hoc analysis exploring the association between the different modified COMPASS autonomic sub-domain scores and FSS scores found significant regressor effects for the orthostatic intolerance (R 2 =0.45, F=21.2, P<0.0001) and secretomotor sub-domains (R 2 =0.09, F=4.8, P=0.04) but not for other autonomic sub-domains. Autonomic dysfunction, in particular orthostatic intolerance, is highly associated with fatigue in PD. Copyright © 2017 Elsevier B.V. All rights reserved.

Physical training associated with Enalapril but not to Losartan, results in better cardiovascular autonomic effects.

PubMed

Maida, Karina Delgado; Gastaldi, Ada Clarice; de Paula Facioli, Tabata; de Araújo, João Eduardo; de Souza, Hugo Celso Dutra

2017-03-01

We investigated the cardiovascular autonomic effects of physical training associated with Enalapril or Losartan pharmacological treatments in spontaneously hypertensive rats (SHR). SHRs, 18weeks of age (N=48) was assigned to either sedentary (N=24) and trained (N=24; aerobic training by swimming for 10wk). Each group was subdivided in 3 subgroups (N=8) vehicle (control); Enalapril (10mg·kg -1 ·d -1 ); and Losartan (5mg·kg -1 ·d -1 ). All animals received a 10-week treatment in drinking water. In the last week of the treatments, the animals had their femoral artery and vein cannulated for blood pressure recording and drug injection, respectively. The autonomic assessment was performed by means of different approaches: double cardiac autonomic block with atropine and propranolol, spectral analysis of heart rate variability (HRV) and systolic arterial pressure (SAPV) and assessment of baroreflex sensitivity (BRS). The groups treated with Enalapril, sedentary and trained, showed more significant decrease in blood pressure when compared to the other groups. Autonomic evaluation showed that the sedentary group treated with Enalapril or Losartan had similar results, characterized by decreased effect of sympathetic tone and/or increased effect of cardiac vagal tone associated with improved BRS. Isolated physical training attenuated only the effect of sympathetic tone. The association of physical training with Enalapril showed the best results, characterized by the predominance of vagal tone in cardiac autonomic balance, increased HRV, reduced SAPV and increased BRS. Enalapril and Losartan promoted similar beneficial cardiovascular autonomic effects in sedentary animals, while only the association of physical training with Enalapril potentiated these effects. Copyright © 2017 Elsevier B.V. All rights reserved.

Advancing Autonomous Operations for Deep Space Vehicles

NASA Technical Reports Server (NTRS)

Haddock, Angie T.; Stetson, Howard K.

2014-01-01

Starting in Jan 2012, the Advanced Exploration Systems (AES) Autonomous Mission Operations (AMO) Project began to investigate the ability to create and execute "single button" crew initiated autonomous activities [1]. NASA Marshall Space Flight Center (MSFC) designed and built a fluid transfer hardware test-bed to use as a sub-system target for the investigations of intelligent procedures that would command and control a fluid transfer test-bed, would perform self-monitoring during fluid transfers, detect anomalies and faults, isolate the fault and recover the procedures function that was being executed, all without operator intervention. In addition to the development of intelligent procedures, the team is also exploring various methods for autonomous activity execution where a planned timeline of activities are executed autonomously and also the initial analysis of crew procedure development. This paper will detail the development of intelligent procedures for the NASA MSFC Autonomous Fluid Transfer System (AFTS) as well as the autonomous plan execution capabilities being investigated. Manned deep space missions, with extreme communication delays with Earth based assets, presents significant challenges for what the on-board procedure content will encompass as well as the planned execution of the procedures.

Independent Living for the Elderly at Home: What is Required?

PubMed Central

Walker, Barbara Prime

1986-01-01

Home care is vital to healthy aging, since living autonomously in the community is the primary interest of the elderly. Breaking the cycle which locks many frail and disabled individuals into a position of dependency requires shared input from a variety of resources in society. Success depends on an accurate assessment of functional ability, knowledge of community support services, and the willingness of health professionals to work co-operatively with others to provide a balance of assistance which is realistic for the local community. PMID:20469462

Software control architecture for autonomous vehicles

NASA Astrophysics Data System (ADS)

Nelson, Michael L.; DeAnda, Juan R.; Fox, Richard K.; Meng, Xiannong

1999-07-01

The Strategic-Tactical-Execution Software Control Architecture (STESCA) is a tri-level approach to controlling autonomous vehicles. Using an object-oriented approach, STESCA has been developed as a generalization of the Rational Behavior Model (RBM). STESCA was initially implemented for the Phoenix Autonomous Underwater Vehicle (Naval Postgraduate School -- Monterey, CA), and is currently being implemented for the Pioneer AT land-based wheeled vehicle. The goals of STESCA are twofold. First is to create a generic framework to simplify the process of creating a software control architecture for autonomous vehicles of any type. Second is to allow for mission specification system by 'anyone' with minimal training to control the overall vehicle functionality. This paper describes the prototype implementation of STESCA for the Pioneer AT.

Effect of Cushing's syndrome - Endogenous hypercortisolemia on cardiovascular autonomic functions.

PubMed

Jyotsna, V P; Naseer, Ali; Sreenivas, V; Gupta, Nandita; Deepak, K K

2011-02-24

Cushing's syndrome is associated with increased cardiovascular morbidity and mortality. It's also associated with other cardiac risk factors like hypertension, diabetes mellitus and obesity. Cardiovascular autonomic function impairment could predict cardiovascular morbidity and mortality. Twenty five patients with Cushing's syndrome without diabetes and twenty five age matched healthy controls underwent a battery of cardiovascular autonomic function tests including deep breath test, Valsalva test, hand grip test, cold pressor test and response to standing from lying position. The rise in diastolic blood pressure on hand grip test and diastolic BP response to cold pressor test in Cushing's patients were significantly less compared to healthy controls (9.83 ± 3.90 vs 20.64 ± 9.55, p<0.001 and 10.09 ± 4.07 vs 15.33 ± 6.26, p<0.01 respectively). The E:I ratio on deep breathing test was also less in the patients in comparison to controls (1.36 ± 0.21 vs 1.53 ± 0.19, p<0.01). Seven patients underwent the same battery of tests 6 months after a curative surgery showing a trend towards normalization with significant improvement in expiratory to inspiratory ratio and sinus arrhythmia delta heart rate. To conclude, this study showed that chronic endogenous hypercortisolism in Cushing's is associated with an impaired sympathetic cardiovascular autonomic functioning. After a curative surgery, some of the parameters tend to improve. Copyright © 2010 Elsevier B.V. All rights reserved.

Equine grass sickness, but not botulism, causes autonomic and enteric neurodegeneration and increases soluble N-ethylmaleimide-sensitive factor attachment receptor protein expression within neuronal perikarya.

PubMed

McGorum, B C; Scholes, S; Milne, E M; Eaton, S L; Wishart, T M; Poxton, I R; Moss, S; Wernery, U; Davey, T; Harris, J B; Pirie, R S

2016-11-01

Equine grass sickness (EGS) is of unknown aetiology. Despite some evidence suggesting that it represents a toxico-infection with Clostridium botulinum types C and/or D, the effect of EGS on the functional targets of botulinum neurotoxins, namely the soluble N-ethylmaleimide-sensitive factor attachment receptor (SNARE) proteins, is unknown. Further, while it is commonly stated that, unlike EGS, equine botulism is not associated with autonomic and enteric neurodegeneration, this has not been definitively assessed. To determine: 1) whether botulism causes autonomic and enteric neurodegeneration; and 2) the effect of EGS on the expression of SNARE proteins within cranial cervical ganglion (CCG) and enteric neuronal perikarya. Descriptive study. Light microscopy was used to compare the morphology of neurons in haematoxylin-eosin stained sections of CCG and ileum from 6 EGS horses, 5 botulism horses and 6 control horses. Immunohistochemistry was used to compare the expression of synaptosomal-associated protein-25, synaptobrevin (Syb) and syntaxin within CCG neurons, and of Syb in enteric neurons, from horses with EGS, horses with botulism and control horses. The concentrations of these SNARE proteins in extracts of CCG from EGS and control horses were compared using quantitative fluorescent western blotting. EGS, but not botulism, was associated with autonomic and enteric neurodegeneration and with increased immunoreactivity for SNARE proteins within neuronal perikarya. Quantitative fluorescent western blotting confirmed increased concentrations of synaptosomal-associated protein-25, Syb and syntaxin within CCG extracts from EGS vs. control horses, with the increases in the latter 2 proteins being statistically significant. The occurrence of autonomic and enteric neurodegeneration, and increased expression of SNARE proteins within neuronal perikarya, in EGS but not botulism, suggests that EGS may not be caused by botulinum neurotoxins. Further investigation of the aetiology of EGS is therefore warranted. © 2015 EVJ Ltd.

Autonomic Cardiovascular Responses in Acclimatized Lowlanders on Prolonged Stay at High Altitude: A Longitudinal Follow Up Study

PubMed Central

Dhar, Priyanka; Sharma, Vijay K.; Hota, Kalpana B.; Das, Saroj K.; Hota, Sunil K.; Srivastava, Ravi B.; Singh, Shashi B.

2014-01-01

Acute exposure to hypobaric hypoxia at high altitude is reported to cause sympathetic dominance that may contribute to the pathophysiology of high altitude illnesses. The effect of prolonged stay at high altitude on autonomic functions, however, remains to be explored. Thus, the present study aimed at investigating the effect of high altitude on autonomic neural control of cardiovascular responses by monitoring heart rate variability (HRV) during chronic hypobaric hypoxia. Baseline electrocardiography (ECG) data was acquired from the volunteers at mean sea level (MSL) (<250 m) in Rajasthan. Following induction of the study population to high altitude (4500–4800 m) in Ladakh region, ECG data was acquired from the volunteers after 6 months (ALL 6) and 18 months of induction (ALL 18). Out of 159 volunteers who underwent complete investigation during acquisition of baseline data, we have only included the data of 104 volunteers who constantly stayed at high altitude for 18 months to complete the final follow up after 18 months. HRV parameters, physiological indices and biochemical changes in serum were investigated. Our results show sympathetic hyperactivation along with compromise in parasympathetic activity in ALL 6 and ALL 18 when compared to baseline data. Reduction of sympathetic activity and increased parasympathetic response was however observed in ALL 18 when compared to ALL 6. Our findings suggest that autonomic response is regulated by two distinct mechanisms in the ALL 6 and ALL 18. While the autonomic alterations in the ALL 6 group could be attributed to increased sympathetic activity resulting from increased plasma catecholamine concentration, the sympathetic activity in ALL 18 group is associated with increased concentration of serum coronary risk factors and elevated homocysteine. These findings have important clinical implications in assessment of susceptibility to cardio-vascular risks in acclimatized lowlanders staying for prolonged duration at high altitude. PMID:24404157

Development of an autonomous treatment planning strategy for radiation therapy with effective use of population-based prior data.

PubMed

Wang, Huan; Dong, Peng; Liu, Hongcheng; Xing, Lei

2017-02-01

Current treatment planning remains a costly and labor intensive procedure and requires multiple trial-and-error adjustments of system parameters such as the weighting factors and prescriptions. The purpose of this work is to develop an autonomous treatment planning strategy with effective use of prior knowledge and in a clinically realistic treatment planning platform to facilitate radiation therapy workflow. Our technique consists of three major components: (i) a clinical treatment planning system (TPS); (ii) a formulation of decision-function constructed using an assemble of prior treatment plans; (iii) a plan evaluator or decision-function and an outer-loop optimization independent of the clinical TPS to assess the TPS-generated plan and to drive the search toward a solution optimizing the decision-function. Microsoft (MS) Visual Studio Coded UI is applied to record some common planner-TPS interactions as subroutines for querying and interacting with the TPS. These subroutines are called back in the outer-loop optimization program to navigate the plan selection process through the solution space iteratively. The utility of the approach is demonstrated by using clinical prostate and head-and-neck cases. An autonomous treatment planning technique with effective use of an assemble of prior treatment plans is developed to automatically maneuver the clinical treatment planning process in the platform of a commercial TPS. The process mimics the decision-making process of a human planner and provides a clinically sensible treatment plan automatically, thus reducing/eliminating the tedious manual trial-and-errors of treatment planning. It is found that the prostate and head-and-neck treatment plans generated using the approach compare favorably with that used for the patients' actual treatments. Clinical inverse treatment planning process can be automated effectively with the guidance of an assemble of prior treatment plans. The approach has the potential to significantly improve the radiation therapy workflow. © 2016 American Association of Physicists in Medicine.

In vivo functional connectome of human brainstem nuclei of the ascending arousal, autonomic, and motor systems by high spatial resolution 7-Tesla fMRI.

PubMed

Bianciardi, Marta; Toschi, Nicola; Eichner, Cornelius; Polimeni, Jonathan R; Setsompop, Kawin; Brown, Emery N; Hämäläinen, Matti S; Rosen, Bruce R; Wald, Lawrence L

2016-06-01

Our aim was to map the in vivo human functional connectivity of several brainstem nuclei with the rest of the brain by using seed-based correlation of ultra-high magnetic field functional magnetic resonance imaging (fMRI) data. We used the recently developed template of 11 brainstem nuclei derived from multi-contrast structural MRI at 7 Tesla as seed regions to determine their connectivity to the rest of the brain. To achieve this, we used the increased contrast-to-noise ratio of 7-Tesla fMRI compared with 3 Tesla and time-efficient simultaneous multi-slice imaging to cover the brain with high spatial resolution (1.1-mm isotropic nominal resolution) while maintaining a short repetition time (2.5 s). The delineated Pearson's correlation-based functional connectivity diagrams (connectomes) of 11 brainstem nuclei of the ascending arousal, motor, and autonomic systems from 12 controls are presented and discussed in the context of existing histology and animal work. Considering that the investigated brainstem nuclei play a crucial role in several vital functions, the delineated preliminary connectomes might prove useful for future in vivo research and clinical studies of human brainstem function and pathology, including disorders of consciousness, sleep disorders, autonomic disorders, Parkinson's disease, and other motor disorders.

Navigation for the new millennium: Autonomous navigation for Deep Space 1

NASA Technical Reports Server (NTRS)

Reidel, J. E.; Bhaskaran, S.; Synnott, S. P.; Desai, S. D.; Bollman, W. E.; Dumont, P. J.; Halsell, C. A.; Han, D.; Kennedy, B. M.; Null, G. W.;

Effects of short-term W-CDMA mobile phone base station exposure on women with or without mobile phone related symptoms.

PubMed

Furubayashi, Toshiaki; Ushiyama, Akira; Terao, Yasuo; Mizuno, Yoko; Shirasawa, Kei; Pongpaibool, Pornanong; Simba, Ally Y; Wake, Kanako; Nishikawa, Masami; Miyawaki, Kaori; Yasuda, Asako; Uchiyama, Mitsunori; Yamashita, Hitomi Kobayashi; Masuda, Hiroshi; Hirota, Shogo; Takahashi, Miyuki; Okano, Tomoko; Inomata-Terada, Satomi; Sokejima, Shigeru; Maruyama, Eiji; Watanabe, Soichi; Taki, Masao; Ohkubo, Chiyoji; Ugawa, Yoshikazu

2009-02-01

To investigate possible health effects of mobile phone use, we conducted a double-blind, cross-over provocation study to confirm whether subjects with mobile phone related symptoms (MPRS) are more susceptible than control subjects to the effect of electromagnetic fields (EMF) emitted from base stations. We sent questionnaires to 5,000 women and obtained 2,472 valid responses from possible candidates; from these, we recruited 11 subjects with MPRS and 43 controls. There were four EMF exposure conditions, each of which lasted 30 min: continuous, intermittent, and sham exposure with and without noise. Subjects were exposed to EMF of 2.14 GHz, 10 V/m (W-CDMA), in a shielded room to simulate whole-body exposure to EMF from base stations, although the exposure strength we used was higher than that commonly received from base stations. We measured several psychological and cognitive parameters pre- and post-exposure, and monitored autonomic functions. Subjects were asked to report on their perception of EMF and level of discomfort during the experiment. The MPRS group did not differ from the controls in their ability to detect exposure to EMF; nevertheless they consistently experienced more discomfort, regardless of whether or not they were actually exposed to EMF, and despite the lack of significant changes in their autonomic functions. Thus, the two groups did not differ in their responses to real or sham EMF exposure according to any psychological, cognitive or autonomic assessment. In conclusion, we found no evidence of any causal link between hypersensitivity symptoms and exposure to EMF from base stations. Copyright 2008 Wiley-Liss, Inc.

Measuring Cardiac Autonomic Nervous System (ANS) Activity in Toddlers - Resting and Developmental Challenges.

PubMed

Bush, Nicole R; Caron, Zoe K; Blackburn, Katherine S; Alkon, Abbey

2016-02-25

The autonomic nervous system (ANS) consists of two branches, the parasympathetic and sympathetic nervous systems, and controls the function of internal organs (e.g., heart rate, respiration, digestion) and responds to everyday and adverse experiences (1). ANS measures in children have been found to be related to behavior problems, emotion regulation, and health (2-7). Therefore, understanding the factors that affect ANS development during early childhood is important. Both branches of the ANS affect young children's cardiovascular responses to stimuli and have been measured noninvasively, via external monitoring equipment, using valid and reliable measures of physiological change (8-11). However, there are few studies of very young children with simultaneous measures of the parasympathetic and sympathetic nervous systems, which limits understanding of the integrated functioning of the two systems. In addition, the majority of existing studies of young children report on infants' resting ANS measures or their reactivity to commonly used mother-child interaction paradigms, and less is known about ANS reactivity to other challenging conditions. We present a study design and standardized protocol for a non-invasive and rapid assessment of cardiac autonomic control in 18 month old children. We describe methods for continuous monitoring of the parasympathetic and sympathetic branches of the ANS under resting and challenge conditions during a home or laboratory visit and provide descriptive findings from our sample of 140 ethnically diverse toddlers using validated equipment and scoring software. Results revealed that this protocol can produce a range of physiological responses to both resting and developmentally challenging conditions, as indicated by changes in heart rate and indices of parasympathetic and sympathetic activity. Individuals demonstrated variability in resting levels, responses to challenges, and challenge reactivity, which provides additional evidence that this protocol is useful for the examination of ANS individual differences for toddlers.

Recovery of the cardiac autonomic nervous and vascular system after maximal cardiopulmonary exercise testing in recreational athletes.

PubMed

Weberruss, Heidi; Maucher, Johannes; Oberhoffer, Renate; Müller, Jan

2018-01-01

The body's adaptation to physical exercise is modulated by sympathetic and parasympathetic (vagal) branches of the autonomic nervous system (ANS). Heart rate variability (HRV), the beat-to-beat variation of the heart, is a proxy measure for ANS activity, whereas blood pressure (BP) is an indicator for cardiovascular function. Impaired vagal activity and lower BP is already described after exercise. However, inconsistent results exist about how long vagal recovery takes and how long post-exercise hypotension persists. Therefore, the aim of this study was to assess HRV and BP 1 h after maximal cardiopulmonary exercise testing (CPET). HRV (Polar RS800CX), peripheral and central BP (Mobil-O-Graph ® ) were prospectively studied in 107 healthy volunteers (47 female, median age 29.0 years) in supine position, before and 60 min after maximal CPET. One hour after terminating CPET measures of HRV were still impaired and post-exercise BP was significantly reduced suggesting an improved vascular function compared to pre levels. HRV parameters post-exercise were 34.7% (RMSSD), 67.2% (pNN50), 57.2% (HF), and 42.7% (LF) lower compared to pre-exercise levels (for all p < 0.001). Median reduction in BP was 5 mmHg for systolic BP (p < 0.001), and 4 mmHg for diastolic BP (p = 0.016) and central systolic post-exercise (p = 0.005). One hour after terminating strenuous exercise, autonomic nervous regulation seems to be postponed which is reflected in reduced HRV, whereas the early recovery of the vasculature, post-exercise hypotension, is still preserved over the recovery period of 1 h.

Autonomic nervous system function assessed by conventional and spectral analysis might be useful in terms of predicting retinal deterioration in persons with type 1 diabetes mellitus.

PubMed

Duvnjak, L; Tomić, M; Blaslov, K; Vučković Rebrina, S

2016-06-01

To determine whether cardiac autonomic dysfunction represents a risk factor for diabetic retinopathy (DR) development and progression in persons with type 1 diabetes mellitus (T1DM). The study comprised 154 normoalbuminuric persons with T1DM divided into two groups according to the DR presence: with and without DR. Cardiovascular autonomic functioning was measured at baseline using conventional and spectral analysis. Participants were re-examined for the DR presence 18months after. The group with DR had longer disease duration compared to the group without DR (20 vrs 11.5years, p<0.001), heart rate coefficient of variation (HRV-CV) at rest and during deep breathing were lower in participants with DR (p=0.001 and 0.004), as well did spectral indices of HRV: low frequency (LF) band, high frequency (HF) band (p=0.003 and 0.022) while LF/HF ratio indicating sympathovagal balance was higher (p=0.037). No difference in glycaemic control or blood pressure value were observed. Twenty-one (13.36%) participants developed non proliferative DR or progressed to proliferative DR. Cox proportional regression showed that the 18months risk from retinal deterioration was reduced by 33.4% by each increase in the HRV-CV of 1%, 12.7% for the same HRV-CV increase during deep breathing while LF band of 1ms(2) results in 8.6% risk reduction. This study provides evidence that DR should not be considered merely a metabolic control manifestation and that HRV-CV as well as spectral indices of HRV might serve as a practical tool to identify a subgroup of T1DM patients with higher risk of retinal deterioration. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Circadian blood pressure variability in type 1 diabetes subjects and their nondiabetic siblings - influence of erythrocyte electron transfer.

PubMed

Matteucci, Elena; Consani, Cristina; Masoni, Maria Chiara; Giampietro, Ottavio

2010-10-05

Normotensive non-diabetic relatives of type 1 diabetes (T1D) patients have an abnormal blood pressure response to exercise testing that is associated with indices of metabolic syndrome and increased oxidative stress. The primary aim of this study was to investigate the circadian variability of blood pressure and the ambulatory arterial stiffness index (AASI) in healthy siblings of T1D patients vs healthy control subjects who had no first-degree relative with T1D. Secondary aims of the study were to explore the influence of both cardiovascular autonomic function and erythrocyte electron transfer activity as oxidative marker on the ambulatory blood pressure profile. Twenty-four hour ambulatory blood pressure monitoring (ABPM) was undertaken in 25 controls, 20 T1D patients and 20 siblings. In addition to laboratory examination (including homeostasis model assessment of insulin sensitivity) and clinical testing of autonomic function, we measured the rate of oxidant-induced erythrocyte electron transfer to extracellular ferricyanide (RBC vfcy). Systolic blood pressure (SBP) midline-estimating statistic of rhythm and pulse pressure were higher in T1D patients and correlated positively with diabetes duration and RBC vfcy; autonomic dysfunction was associated with diastolic BP ecphasia and increased AASI. Siblings had higher BMI, lower insulin sensitivity, larger SBP amplitude, and higher AASI than controls. Daytime SBP was positively, independently associated with BMI and RBC vfcy. Among non-diabetic people, there was a significant correlation between AASI and fasting plasma glucose. Siblings of T1D patients exhibited a cluster of sub-clinical metabolic abnormalities associated with consensual perturbations in BP variability. Moreover, our findings support, in a clinical setting, the proposed role of transplasma membrane electron transport systems in vascular pathobiology.

Independent validation of the scales for outcomes in Parkinson's disease-autonomic (SCOPA-AUT).

PubMed

Rodriguez-Blazquez, C; Forjaz, M J; Frades-Payo, B; de Pedro-Cuesta, J; Martinez-Martin, P

2010-02-01

Autonomic dysfunction is common in Parkinson's disease (PD) and causes a great impact in health-related quality of life (HRQL) and functional status of patients. This study is the first independent validation of the Scales for Outcomes in PD-Autonomic (SCOPA-AUT). In an observational, cross-sectional study (ELEP Study), 387 PD patients were assessed using, in addition to the SCOPA-AUT, the Hoehn and Yahr staging, SCOPA-Motor, SCOPA-Cognition, Cumulative Illness Rating Scale-Geriatrics, modified Parkinson Psychosis Rating Scale, Clinical Impression of Severity Index for PD, Hospital Anxiety and Depression Scale, SCOPA-Sleep, SCOPA-Psychosocial, pain and fatigue visual analogue scales, and EQ-5D. SCOPA-AUT acceptability, internal consistency, construct validity, and precision were explored. Data quality was satisfactory (97%). SCOPA-AUT total score did not show floor or ceiling effect, and skewness was 0.40. Cronbach's alpha coefficients ranged from 0.64 (Cardiovascular and Thermorregulatory subscales) to 0.95 (Sexual dysfunction, women). Item homogeneity index was low (0.24) for Gastrointestinal subscale. Factor analysis identified eight factors for men (68% of the variance) and seven factors for women (65% of the variance). SCOPA-AUT correlated at a high level with specific HRQL and functional measures (r(S) = 0.52-0.56). SCOPA-AUT scores were higher for older patients, for more advanced disease, and for patients treated only with levodopa (Kruskal-Wallis test, P < 0.01). Standard error of measurement for SCOPA-AUT subscales was 0.81 (sexual, men) - 2.26 (gastrointestinal). Despite its heterogeneous content, which determines some weaknesses in the psychometric attributes of its subscales, SCOPA-AUT is an acceptable, consistent, valid and precise scale.

Automation study for space station subsystems and mission ground support

NASA Technical Reports Server (NTRS)

1985-01-01

An automation concept for the autonomous operation of space station subsystems, i.e., electric power, thermal control, and communications and tracking are discussed. To assure that functions essential for autonomous operations are not neglected, an operations function (systems monitoring and control) is included in the discussion. It is recommended that automated speech recognition and synthesis be considered a basic mode of man/machine interaction for space station command and control, and that the data management system (DMS) and other systems on the space station be designed to accommodate fully automated fault detection, isolation, and recovery within the system monitoring function of the DMS.

Transfer function analysis of the autonomic response to respiratory activity during random interval breathing

NASA Technical Reports Server (NTRS)

Chen, M. H.; Berger, R. D.; Saul, J. P.; Stevenson, K.; Cohen, R. J.

1987-01-01

We report a new method for the noninvasive characterization of the frequency response of the autonomic nervous system (ANS) in mediating fluctuations in heart rate (HR). The approach entails computation of the transfer function magnitude and phase between instantaneous lung volume and HR. Broad band fluctuations in lung volume were initiated when subjects breathed on cue to a sequence of beeps spaced randomly in time. We studied 10 subjects in both supine and standing positions. The transfer function, averaged among all the subjects, showed systematic differences between the two postures, reflecting the differing frequency responses of the sympathetic and parasympathetic divisions of the ANS.

Clinical characteristics of a novel subgroup of chronic fatigue syndrome patients with postural orthostatic tachycardia syndrome.

PubMed

Lewis, I; Pairman, J; Spickett, G; Newton, J L

2013-05-01

A significant proportion of patients with chronic fatigue syndrome (CFS) also have postural orthostatic tachycardia syndrome (POTS). We aimed to characterize these patients and differentiate them from CFS patients without POTS in terms of clinical and autonomic features. A total of 179 patients with CFS (1994 Centers for Disease Control and Prevention criteria) attending one of the largest Department of Health-funded CFS clinical services were included in this study. Outcome measures were as follows: (i) symptom assessment tools including the fatigue impact scale, Chalder fatigue scale, Epworth sleepiness scale (ESS), orthostatic grading scale (OGS) and hospital anxiety and depression scale (HADS-A and -D, respectively), (ii) autonomic function analysis including heart rate variability and (iii) haemodynamic responses including left ventricular ejection time and systolic blood pressure drop upon standing. CFS patients with POTS (13%, n = 24) were younger (29 ± 12 vs. 42 ± 13 years, P < 0.0001), less fatigued (Chalder fatigue scale, 8 ± 4 vs. 10 ± 2, P = 0.002), less depressed (HADS-D, 6 ± 4 vs. 9 ± 4, P = 0.01) and had reduced daytime hypersomnolence (ESS, 7 ± 6 vs. 10 ± 5, P = 0.02), compared with patients without POTS. In addition, they exhibited greater orthostatic intolerance (OGS, 11 ± 5; P < 0.0001) and autonomic dysfunction. A combined clinical assessment tool of ESS ≤9 and OGS ≥9 identifies accurately CFS patients with POTS with 100% positive and negative predictive values. The presence of POTS marks a distinct clinical group of CFS patents, with phenotypic features differentiating them from those without POTS. A combination of validated clinical assessment tools can determine which CFS patients have POTS with a high degree of accuracy, and thus potentially identify those who require further investigation and consideration for therapy to control heart rate. © 2013 The Association for the Publication of the Journal of Internal Medicine.

Cardiovascular response to lower body negative pressure stimulation before, during, and after space flight

NASA Technical Reports Server (NTRS)

Baisch, F.; Beck, L.; Blomqvist, G.; Wolfram, G.; Drescher, J.; Rome, J. L.; Drummer, C.

2000-01-01

BACKGROUND: It is well known that space travel cause post-flight orthostatic hypotension and it was assumed that autonomic cardiovascular control deteriorates in space. Lower body negative pressure (LBNP) was used to assess autonomic function of the cardiovascular system. METHODS: LBNP tests were performed on six crew-members before and on the first days post-flight in a series of three space missions. Additionally, two of the subjects performed LBNP tests in-flight. LBNP mimics fluid distribution of upright posture in a gravity independent way. It causes an artificial sequestration of blood, reduces preload, and filtrates plasma into the lower part of the body. Fluid distribution was assessed by bioelectrical impedance and anthropometric measurements. RESULTS: Heart rate, blood pressure, and total peripheral resistance increased significantly during LBNP experiments in-flight. The decrease in stroke volume, the increased pooling of blood, and the increased filtration of plasma into the lower limbs during LBNP indicated that a plasma volume reduction and a deficit of the interstitial volume of lower limbs rather than a change in cardiovascular control was responsible for the in-flight response. Post-flight LBNP showed no signs of cardiovascular deterioration. The still more pronounced haemodynamic changes during LBNP reflected the expected behaviour of cardiovascular control faced with less intravascular volume. In-flight, the status of an intra-and extravascular fluid deficit increases sympathetic activity, the release of vasoactive substances and consequently blood pressure. Post-flight, blood pressure decreases significantly below pre-flight values after restoration of volume deficits. CONCLUSION: We conclude that the cardiovascular changes in-flight are a consequence of a fluid deficit rather than a consequence of changes in autonomic signal processing.

Maturation of Heart Rate and Blood Pressure Variability during Sleep in Term-Born Infants

PubMed Central

Yiallourou, Stephanie R.; Sands, Scott A.; Walker, Adrian M.; Horne, Rosemary S.C.

2012-01-01

Study Objectives: Abnormal blood pressure control is implicated in the sudden infant death syndrome (SIDS). However, no data exist on normal development of blood pressure control during infancy. This study assessed maturation of autonomic control of blood pressure and heart rate during sleep within the first 6 months of life. Participants: Term infants (n = 31) were studied longitudinally at 2-4 weeks, 2-3 months, and 5-6 months postnatal age. Interventions: Infants underwent daytime polysomnography at each age studied. Blood pressure and heart rate were recorded during quiet (QS) and active (AS) sleep in undisturbed baseline and head-up tilt conditions. Measurements and Results: Autonomic control was assessed using spectral indices of blood pressure and heart rate variability (BPV and HRV) in ranges of low frequency (LF, reflecting sympathetic + parasympathetic activity) and high frequency (HF, parasympathetic activity), total power (LF+HF), and LF/HF ratio (sympathovagal balance). With increasing postnatal age and predominantly during QS, HRV-LF, HRV-HF, and HRV total power increased, while HRV-LF/HF decreased. BPV-LF/HF also decreased with postnatal age. All changes were evident in both baseline and head-up tilt conditions. BPV-LF and BPV total power during tilts were markedly reduced in QS versus AS at each age. Conclusions: In sleeping infants, sympathetic vascular modulation of the circulation decreases with age, while parasympathetic control of heart rate is strengthened. These normative data will aid in the early identification of conditions where autonomic function is impaired, such as in SIDS. Citation: Yiallourou SR; Sands SA; Walker AM; Horne RSC. Maturation of heart rate and blood pressure variability during sleep in term-born infants. SLEEP 2012;35(2):177-186. PMID:22294807

Monitoring and Correcting Autonomic Function Aboard Mir: NASA Technology Used in Space and on Earth to Facilitate Adaptation

NASA Technical Reports Server (NTRS)

Cowings, P.; Toscano, W.; Taylor, B.; DeRoshia, C.; Kornilova, L.; Koslovskaya, I.; Miller, N.

1999-01-01

The broad objective of the research was to study individual characteristics of human adaptation to long duration spaceflight and possibilities of their correction using autonomic conditioning. The changes in autonomic state during adaptation to microgravity can have profound effects on the operational efficiency of crewmembers and may result in debilitating biomedical symptoms. Ground-based and inflight experiment results showed that certain responses of autonomic nervous system were correlated with, or consistently preceded, reports of performance decrements or the symptoms. Autogenic-Feedback-Training Exercise (AFTE) is a physiological conditioning method that has been used to train people to voluntary control several of their own physiological responses. The specific objectives were: 1) To study human autonomic nervous system (ANS) responses to sustained exposure to microgravity; 2) To study human behavior/performance changes related to physiology; 3) To evaluate the effectiveness of preflight autonomic conditioning (AFTE) for facilitating adaptation to space and readaptation to Earth; and 4) To archive these data for the NASA Life Sciences Data Archive and thereby make this information available to the international scientific community.

Education for Critical Thinking: Can It Be Non-Indoctrinative?

ERIC Educational Resources Information Center

Cuypers, Stefaan E.; Haji, Ishtiyaque

2006-01-01

An ideal of education is to ensure that our children develop into autonomous critical thinkers. The "indoctrination objection", however, calls into question whether education, aimed at cultivating autonomous critical thinkers, is possible. The core of the concern is that since the young child lacks even modest capacities for assessing reasons, the…

Assessing Plankton and Particles with an Autonomous Imaging LOPC

DTIC Science & Technology

2007-09-30

been modified to operate autonomously by auto-starting its programs on power-up and storing its data to an onboard flashcard . Since data transfer to... flashcard is a slow process, storage will occur when the AUV surfaces for a position fix. Data acquisition will commence as the AUV descends >5m

Incidence of nonamyloidogenic mutations in the transthyretin gene in patients with autonomic and small fiber neuropathy.

PubMed

Levine, Todd D; Bland, Ruth J

2018-01-01

Mutations of the transthyretin (TTR) gene have been associated with polyneuropathy; the protein product has a tendency to form amyloid deposits in the peripheral nervous system. Patients with small fiber neuropathy (SFN) with or without autonomic symptoms were given skin biopsies to assess nerve fiber density. Any patient with autonomic symptoms was assessed for autonomic neuropathy (AN). If testing revealed no clear cause of neuropathy, the TTR gene was sequenced. Thirty-six percent of patients were found to harbor at least 1 mutation in the TTR gene sequence (variants of unknown significance [VUS]). Of 24 patients diagnosed with SFN, 8% of patients had a point mutation (c76G>A). Of those patients who were diagnosed with both SFN and AN, 68% of patients had a VUS within the TTR gene (c76G>A, c337-18G>C). The results suggest an association between presumed nonamyloidogenic mutations in the TTR gene and the development of AN and SFN. Muscle Nerve 57: 140-142, 2017. © 2017 Wiley Periodicals, Inc.

Effects of inspiratory muscle training on autonomic activity, endothelial vasodilator function, and N-terminal pro-brain natriuretic peptide levels in chronic heart failure.

PubMed

Laoutaris, Ioannis D; Dritsas, Athanasios; Brown, Margaret D; Manginas, Athanassios; Kallistratos, Manolis S; Chaidaroglou, Antigoni; Degiannis, Dimitrios; Alivizatos, Peter A; Cokkinos, Dennis V

2008-01-01

To assess the effects of inspiratory muscle training (IMT) on autonomic activity, endothelial function, and N-terminal pro-brain natriuretic peptide (NT-proBNP) levels in patients with chronic heart failure. Using age- and sex-matched controlled study, 23 patients (mean left ventricular ejection fraction 29 +/- 2%) were assigned to either a high-intensity training group (n = 14), New York Heart Association (NYHA) class II (n = 9)/III (n = 5), or a low-intensity training group (n = 9), NYHA class II (n = 6)/III (n = 3), exercising at 60% and 15% of sustained maximum inspiratory pressure (SPImax), respectively, 3 times per week for 10 weeks. Before and following IMT, patients underwent cardiopulmonary exercise testing and dyspnea evaluation on exertion. Sympathovagal balance was assessed by heart rate variability (HRV) from 24-hour electrocardiogram and endothelial function, using venous occlusion plethysmography. Serum levels of NT-proBNP were determined. High-intensity training group improved maximum inspiratory pressure (PImax, 105.4 +/- 5.3 vs 79.1 +/- 5 cm H2O, P = .001), SPImax (511 +/- 42 vs 308 +/- 28 cm H2O/sec/10, P = .001), peak oxygen consumption (19 +/- 1.2 vs 17.1 +/- 0.7 mL.kgmin, P = .01) and dyspnea (17.6 +/- 0.2 vs 18.1 +/- 0.1, P = .02). Endothelium-dependent vasodilation, HRV, and NT-proBNP levels were not altered. Low-intensity training group increased only the PImax (97.6 +/- 11.3 vs 84.2 +/- 8.7 cm H2O, P = .03). Improvement in dyspnea and exercise tolerance after IMT were not associated with changes in markers of HRV, endothelial function, and NT-proBNP in patients with mild to moderate chronic heart failure. Further studies on the effects of IMT in advanced heart failure would be worthwhile.

Assessment of a visually guided autonomous exploration robot

NASA Astrophysics Data System (ADS)

Harris, C.; Evans, R.; Tidey, E.

2008-10-01

A system has been developed to enable a robot vehicle to autonomously explore and map an indoor environment using only visual sensors. The vehicle is equipped with a single camera, whose output is wirelessly transmitted to an off-board standard PC for processing. Visual features within the camera imagery are extracted and tracked, and their 3D positions are calculated using a Structure from Motion algorithm. As the vehicle travels, obstacles in its surroundings are identified and a map of the explored region is generated. This paper discusses suitable criteria for assessing the performance of the system by computer-based simulation and practical experiments with a real vehicle. Performance measures identified include the positional accuracy of the 3D map and the vehicle's location, the efficiency and completeness of the exploration and the system reliability. Selected results are presented and the effect of key system parameters and algorithms on performance is assessed. This work was funded by the Systems Engineering for Autonomous Systems (SEAS) Defence Technology Centre established by the UK Ministry of Defence.

Functional Based Adaptive and Fuzzy Sliding Controller for Non-Autonomous Active Suspension System

NASA Astrophysics Data System (ADS)

Huang, Shiuh-Jer; Chen, Hung-Yi

In this paper, an adaptive sliding controller is developed for controlling a vehicle active suspension system. The functional approximation technique is employed to substitute the unknown non-autonomous functions of the suspension system and release the model-based requirement of sliding mode control algorithm. In order to improve the control performance and reduce the implementation problem, a fuzzy strategy with online learning ability is added to compensate the functional approximation error. The update laws of the functional approximation coefficients and the fuzzy tuning parameters are derived from the Lyapunov theorem to guarantee the system stability. The proposed controller is implemented on a quarter-car hydraulic actuating active suspension system test-rig. The experimental results show that the proposed controller suppresses the oscillation amplitude of the suspension system effectively.

Identification of low and high frequency ranges for heart rate variability and blood pressure variability analyses using pharmacological autonomic blockade with atropine and propranolol in swine.

USDA-ARS?s Scientific Manuscript database

Understanding autonomic nervous system functioning, which mediates behavioral and physiological responses to stress, offers great potential for evaluation of farm animal stress and welfare. Evaluation of heart rate variability (HRV) and blood pressure variability (BPV), using time and frequency doma...

Takotsubo-like Myocardial Dysfunction in a Patient with Botulism.

PubMed

Tonomura, Shuichi; Kakehi, Yoshiaki; Sato, Masatoshi; Naito, Yuki; Shimizu, Hisao; Goto, Yasunobu; Takahashi, Nobuyuki

2017-11-01

Botulinum toxin A (BTXA) can disrupt the neuromuscular and autonomic functions. We herein report a case of autonomic system dysfunction that manifested as Takotsubo-like myocardial dysfunction in a patient with botulism. Takotsubo syndrome results in acute cardiac insufficiency, another fatal complication of botulism in addition to respiratory muscle paralysis, particularly in patients with cardiovascular disease.

Takotsubo-like Myocardial Dysfunction in a Patient with Botulism

PubMed Central

Tonomura, Shuichi; Kakehi, Yoshiaki; Sato, Masatoshi; Naito, Yuki; Shimizu, Hisao; Goto, Yasunobu; Takahashi, Nobuyuki

2017-01-01

Botulinum toxin A (BTXA) can disrupt the neuromuscular and autonomic functions. We herein report a case of autonomic system dysfunction that manifested as Takotsubo-like myocardial dysfunction in a patient with botulism. Takotsubo syndrome results in acute cardiac insufficiency, another fatal complication of botulism in addition to respiratory muscle paralysis, particularly in patients with cardiovascular disease. PMID:28924131

Approximating a retarded-advanced differential equation that models human phonation

NASA Astrophysics Data System (ADS)

Teodoro, M. Filomena

2017-11-01

In [1, 2, 3] we have got the numerical solution of a linear mixed type functional differential equation (MTFDE) introduced initially in [4], considering the autonomous and non-autonomous case by collocation, least squares and finite element methods considering B-splines basis set. The present work introduces a numerical scheme using least squares method (LSM) and Gaussian basis functions to solve numerically a nonlinear mixed type equation with symmetric delay and advance which models human phonation. The preliminary results are promising. We obtain an accuracy comparable with the previous results.

Recurrent myocardial infarction: Mechanisms of free-floating adaptation and autonomic derangement in networked cardiac neural control

PubMed Central

Ardell, Jeffrey L.; Shivkumar, Kalyanam; Armour, J. Andrew

2017-01-01

The cardiac nervous system continuously controls cardiac function whether or not pathology is present. While myocardial infarction typically has a major and catastrophic impact, population studies have shown that longer-term risk for recurrent myocardial infarction and the related potential for sudden cardiac death depends mainly upon standard atherosclerotic variables and autonomic nervous system maladaptations. Investigative neurocardiology has demonstrated that autonomic control of cardiac function includes local circuit neurons for networked control within the peripheral nervous system. The structural and adaptive characteristics of such networked interactions define the dynamics and a new normal for cardiac control that results in the aftermath of recurrent myocardial infarction and/or unstable angina that may or may not precipitate autonomic derangement. These features are explored here via a mathematical model of cardiac regulation. A main observation is that the control environment during pathology is an extrapolation to a setting outside prior experience. Although global bounds guarantee stability, the resulting closed-loop dynamics exhibited while the network adapts during pathology are aptly described as ‘free-floating’ in order to emphasize their dependence upon details of the network structure. The totality of the results provide a mechanistic reasoning that validates the clinical practice of reducing sympathetic efferent neuronal tone while aggressively targeting autonomic derangement in the treatment of ischemic heart disease. PMID:28692680

Validation of the Korean Version of the Scale for Outcomes in Parkinson’s Disease-Autonomic

PubMed Central

Kim, Ji-Young; Song, In-Uk; Koh, Seong-Beom; Ahn, Tae-Beom; Kim, Sang Jin; Cheon, Sang-Myung; Cho, Jin Whan; Kim, Yun Joong; Ma, Hyeo-Il; Park, Mee-Young; Baik, Jong Sam; Lee, Phil Hyu; Chung, Sun Ju; Kim, Jong-Min; Kim, Han-Joon; Sung, Young-Hee; Kwon, Do Young; Lee, Jae-Hyeok; Lee, Jee-Young; Kim, Ji Sun; Yun, Ji Young; Kim, Hee Jin; Hong, Jin Young; Kim, Mi-Jung; Youn, Jinyoung; Kim, Ji Seon; Oh, Eung Seok; Yang, Hui-Jun; Yoon, Won Tae; You, Sooyeoun; Kwon, Kyum-Yil; Park, Hyung-Eun; Lee, Su-Yun; Kim, Younsoo; Kim, Hee-Tae; Kim, Joong-Seok

2017-01-01

Objective Autonomic symptoms are commonly observed in patients with Parkinson’s disease (PD) and often limit the activities of daily living. The Scale for Outcomes in Parkinson’s disease-Autonomic (SCOPA-AUT) was developed to evaluate and quantify autonomic symptoms in PD. The goal of this study was to translate the original SCOPA-AUT, which was written in English, into Korean and to evaluate its reliability and validity for Korean PD patients. Methods For the translation, the following processes were performed: forward translation, backward translation, expert review, pretest of the pre-final version and development of the final Korean version of SCOPA-AUT (K-SCOPA-AUT). In total, 127 patients with PD from 31 movement disorder clinics of university-affiliated hospitals in Korea were enrolled in this study. All patients were assessed using the K-SCOPA-AUT and other motor, non-motor, and quality of life scores. Test-retest reliability for the K-SCOPA-AUT was assessed over a time interval of 10−14 days. Results The internal consistency and reliability of the K-SCOPA-AUT was 0.727 as measured by the mean Cronbach’s α-coefficient. The test-retest correlation reliability was 0.859 by the Guttman split-half coefficient. The total K-SCOPA-AUT score showed a positive correlation with other non-motor symptoms [the Korean version of non-motor symptom scale (K-NMSS)], activities of daily living (Unified Parkinson’s Disease Rating Scale part II) and quality of life [the Korean version of Parkinson’s Disease Quality of Life 39 (K-PDQ39)]. Conclusion The K-SCOPA-AUT had good reliability and validity for the assessment of autonomic dysfunction in Korean PD patients. Autonomic symptom severities were associated with many other motor and non-motor impairments and influenced quality of life. PMID:28122431

Association between aerobic fitness and indices of autonomic regulation: cardiovascular risk implications.

PubMed

Sala, Roberto; Malacarne, Mara; Pagani, Massimo; Lucini, Daniela

2016-06-01

In the general population higher levels of exercise capacity seem to protect the cardiovascular system with effects well beyond traditional risk factors. We hypothesize that this phenomenon, called "risk factor gap", could be ascribed to functional components, such as autonomic adaptation to aerobic training. In 257 subjects (age 36.2±0.8 years) we measured VO2peak (incremental cycling exercise), together with arterial pressure and autonomic proxies (baroreflex gain, R-R variance and standing induced increase in marker of excitatory oscillatory regulation of the SA node, ∆LFRRnu). Autonomic proxies appeared significantly correlated with indicators of aerobic fitness (age and gender corrected correlation between VO2peak, baroreflex gain: r=0.277, P<0.001, and DAP r=-0.228, P<0.001). Subsequently, subjects were subdivided in three age and gender adjusted categories of VO2peak (poor, medium and good). Autonomic indices and arterial pressure appeared significantly ordered with categories of VO2peak (P<0.006). In addition, within these categories the proportion of subjects with a desirable autonomic and pressure profile becomes significantly greater with better fitness levels. The strong ordered relationship between categories of aerobic fitness and autonomic proxies speaks in favor of a complementary role of the autonomic nervous system in the management of cardiovascular risk factor gap at a population level.

Children's Sleep and Autonomic Function: Low Sleep Quality Has an Impact on Heart Rate Variability

PubMed Central

Michels, Nathalie; Clays, Els; De Buyzere, Marc; Vanaelst, Barbara; De Henauw, Stefaan; Sioen, Isabelle

2013-01-01

Objectives: Short sleep duration and poor sleep quality in children have been associated with concentration, problem behavior, and emotional instability, but recently also with disrupted autonomic nervous function, which predicts cardiovascular health. Heart rate variability (HRV) was used as noninvasive indicator of autonomic function to examine the influence of sleep. Design: Cross-sectional and longitudinal observational study on the effect of sleep on HRV Participants: Belgian children (5-11 years) of the ChiBS study in 2010 (N = 334) and 2011 (N = 293). Interventions: N/A. Methods: Sleep duration was reported and in a subgroup sleep quality (efficiency, latency, awakenings) was measured with accelerometry. High-frequency (HF) power and autonomic balance (LF/HF) were calculated on supine 5-minute HRV measurements. Stress was measured by emotion and problem behavior questionnaires. Sleep duration and quality were used as HRV predictors in corrected cross-sectional and longitudinal regressions. Stress was tested as mediator (intermediate pathway) or moderator (interaction) in sleep-HRV associations. Results: In both cross-sectional and longitudinal analyses, long sleep latency could predict lower HF (parasympathetic activity), while nocturnal awakenings, sleep latency, low sleep efficiency, and low corrected sleep duration were related to higher LF/HF (sympathetic/parasympathetic balance). Parental reported sleep duration was not associated with HRV. The significances remained after correction for stress. Stress was not a mediator, but a moderator (enhancer) in the relationship between sleep quality and HRV. Conclusions: Low sleep quality but not parent-reported low sleep duration leads to an unhealthier heart rate variability pattern (sympathetic over parasympathetic dominance). This stresses the importance of good sleep quality for cardiovascular health in children. Citation: Michels N; Clays E; De Buyzere M; Vanaelst B; De Henauw S; Sioen I. Children's sleep and autonomic function: low sleep quality has an impact on heart rate variability. SLEEP 2013;36(12):1939-1946. PMID:24293769

Regular Football Practice Improves Autonomic Cardiac Function in Male Children.

PubMed

Fernandes, Luis; Oliveira, Jose; Soares-Miranda, Luisa; Rebelo, Antonio; Brito, Joao

2015-09-01

The role of the autonomic nervous system (ANS) in the cardiovascular regulation is of primal importance. Since it has been associated with adverse conditions such as cardiac arrhythmias, sudden death, sleep disorders, hypertension and obesity. The present study aimed to investigate the impact of recreational football practice on the autonomic cardiac function of male children, as measured by heart rate variability. Forty-seven male children aged 9 - 12 years were selected according to their engagement with football oriented practice outside school context. The children were divided into a football group (FG; n = 22) and a control group (CG; n = 25). The FG had regular football practices, with 2 weekly training sessions and occasional weekend matches. The CG was not engaged with any physical activity other than complementary school-based physical education classes. Data from physical activity, physical fitness, and heart rate variability measured in time and frequency domains were obtained. The anthropometric and body composition characteristics were similar in both groups (P > 0.05). The groups were also similar in time spent daily on moderate-to-vigorous physical activities (FG vs. CG: 114 ± 64 vs. 87 ± 55 minutes; P > 0.05). However, the FG performed better (P < 0.05) in Yo-Yo intermittent endurance test (1394 ± 558 vs. 778 ± 408 m) and 15-m sprint test (3.06 ± 0.17 vs. 3.20 ± 0.23 s). Also, the FG presented enhanced autonomic function. Significant differences were detected (P < 0.05) between groups for low frequency normalized units (38.0 ± 15.2 vs. 47.3 ± 14.2 n.u (normalized units)), high frequency normalized units (62.1 ± 15.2 vs. 52.8 ± 14.2 n.u.), and LF:HF ratio (0.7 ± 0.4 vs. 1.1 ± 0.6 ms(2)). Children engaged with regular football practice presented enhanced physical fitness and autonomic function, by increasing vagal tone at rest.

Regular Football Practice Improves Autonomic Cardiac Function in Male Children

PubMed Central

Fernandes, Luis; Oliveira, Jose; Soares-Miranda, Luisa; Rebelo, Antonio; Brito, Joao

2015-01-01

Background: The role of the autonomic nervous system (ANS) in the cardiovascular regulation is of primal importance. Since it has been associated with adverse conditions such as cardiac arrhythmias, sudden death, sleep disorders, hypertension and obesity. Objectives: The present study aimed to investigate the impact of recreational football practice on the autonomic cardiac function of male children, as measured by heart rate variability. Patients and Methods: Forty-seven male children aged 9 - 12 years were selected according to their engagement with football oriented practice outside school context. The children were divided into a football group (FG; n = 22) and a control group (CG; n = 25). The FG had regular football practices, with 2 weekly training sessions and occasional weekend matches. The CG was not engaged with any physical activity other than complementary school-based physical education classes. Data from physical activity, physical fitness, and heart rate variability measured in time and frequency domains were obtained. Results: The anthropometric and body composition characteristics were similar in both groups (P > 0.05). The groups were also similar in time spent daily on moderate-to-vigorous physical activities (FG vs. CG: 114 ± 64 vs. 87 ± 55 minutes; P > 0.05). However, the FG performed better (P < 0.05) in Yo-Yo intermittent endurance test (1394 ± 558 vs. 778 ± 408 m) and 15-m sprint test (3.06 ± 0.17 vs. 3.20 ± 0.23 s). Also, the FG presented enhanced autonomic function. Significant differences were detected (P < 0.05) between groups for low frequency normalized units (38.0 ± 15.2 vs. 47.3 ± 14.2 n.u (normalized units)), high frequency normalized units (62.1 ± 15.2 vs. 52.8 ± 14.2 n.u.), and LF:HF ratio (0.7 ± 0.4 vs. 1.1 ± 0.6 ms2). Conclusions: Children engaged with regular football practice presented enhanced physical fitness and autonomic function, by increasing vagal tone at rest. PMID:26448848

Effects and biological limitations of +Gz acceleration on the autonomic functions-related circulation in rats.

PubMed

Nishida, Yasuhiro; Maruyama, Satoshi; Shouji, Ichiro; Kemuriyama, Takehito; Tashiro, Akimasa; Ohta, Hiroyuki; Hagisawa, Kohsue; Hiruma, Megumi; Yokoe, Hidetake

2016-11-01

The effects of gravitational loading (G load) on humans have been studied ever since the early 20th century. After the dangers of G load in the vertical head-to-leg direction (+Gz load) became evident, many animal experiments were performed between 1920 and 1945 in an effort to identify the origins of high G-force-induced loss of consciousness (G-LOC), which led to development of the anti-G suit. The establishment of norms and training for G-LOC prevention resulted in a gradual decline in reports of animal experiments on G load, a decline that steepened with the establishment of anti-G techniques in humans, such as special breathing methods and skeletal muscle contraction, called an anti-G straining maneuver, which are voluntary physiological functions. Because the issue involves humans during flight, the effects on humans themselves are clearly of great importance, but ethical considerations largely preclude any research on the human body that probes to any depth the endogenous physiological states and functions. The decline in reports on animal experiments may therefore signify a general decline in research into the changes seen in the various involuntary, autonomic functions. The declining number of related reports on investigations of physiological autonomic systems other than the circulatory system seems to bear this out. In this review, we therefore describe our findings on the effects of G load on the autonomic nervous system, cardiac function, cerebral blood flow, tissue oxygen level, and other physiological autonomic functions as measured in animal experiments, including denervation or pharmacological blocking, in an effort to present the limits and the mechanisms of G-load response extending physiologically. We demonstrate previously unrecognized risks due to G load, and also describe fundamental research aimed at countering these effects and development of a scientific training measure devised for actively enhancing +Gz tolerance in involuntary, autonomic system functions. The research described here is rough and incomplete, but it is offered as a beginning, in the hope that researchers may find it of reference and carry the effort toward completion. The advances described here include (1) a finding that cerebral arterial perfusion pressure decreases to nearly zero under +5.0 Gz loads, (2) indications that G load may cause myocardial microinjuries, (3) detection of differences between cerebral regions in tissue-oxygen level under +3.0 Gz load, (4) discovery that hypotension is deeper under decreasing +Gz loads than increasing +Gz loads with use of an anti-G system, due in part to suppression of baroreceptor reflex, and (5) revelations and efforts investigating new measures to reduce cerebral hypotension, namely the "teeth-clenching pressor response" and preconditioning with slight but repeated G loads.

The influence of oxazaphosphorines alkylating agents on autonomic nervous system activity in rat experimental cystitis model.

PubMed

Dobrek, Łukasz; Baranowska, Agnieszka; Thor, Piotr J

2013-01-01

The oxazaphosphorines alkylating agents (cyclophosphamide; CP and ifosfamide; IF) are often used in common clinical practice. However, treatment with CP/IF is burdened with the risk of many adverse drug reactions, especially including hemorrhagic cystitis (HC) that is associated with bladder overactivity symptoms (OAB). The HC pathophysiology is still not fully displayed; it seems that autonomic nervous system (ANS) functional abnormalities play important role in this disturbance. The aim of our study was to reveal the potential ANS differences in rat experimental HC model, evoked by CP and IF by an indirect ANS assessment--heart rate variability (HRV) study. We carried out our experimental research in three essential groups: control group (group 1), cyclophosphamide-induced HC (CP-HC; group 2) one and ifosfamide-induced HC (IF-HC; group 3) one. CP was i.p. administrated four times in dose of 75 mg/kg body weight while IF-treated rats received i.p. five drug doses; 50 mg/kg body weight. Control rats were administrated i.p. vehicle in appropriate volumes as CP/IF treated animals. HRV studies were performed the next day after the last oxazaphosphorines dose. Standard time- and spectral (frequency) domain parameters were estimated. We confirmed the HC development after both CP/IF in macroscopic assessment and bladder wet weight measurement; however, it was more aggravated in CP-HC group. Moreover, we demonstrated HRV disturbances, suggesting ANS impairment after both studied oxazaphosphorines, however, consistent with the findings mentioned above, the autonomic dysfunction was more emphasized after CP. CP treatment was also associated with changes of non-normalized HRV spectral components percentage distribution--a marked very low frequency--VLF [%] increase together with low frequency--LF [%] and high frequency--HF [%] decrease were observed. Taking into consideration the next findings, demonstrating the lack of both normalized power spectral components (nLF and nHF) values, the VLF percentage change seems to be of special meaning. IF produced smaller autonomic disturbances, and gentler bladders histological abnormalities comparing to CP. However, similar to CP, VLF [%] relative augmentation together with LF [%] and HF [%] drop accompanied the global ANS activity decrease. Additionally, in the case of IF treatment, a slight trend of nLF increase with nHF decrease was noted, suggesting the possible functional rearrangement between sympathetic (nLF) and parasympathetic (nHF) tension. It seems possible that the vagal withdrawal and--as a consequence--sympathetic overactivity, reflected by VLF [%] enlargement and HF and LF [%] diminishing (as well as LF and HF values decrease), may be an evidence of impaired anti-inflammatory cholinergic pathway, aggravating bladder inflammatory lesions. To sum up, our study showed ANS impairment in both CP- and IF-evoked experimental HC that was reflected in HRV recordings. HRV study, thus, may be considered to be a diagnostic tool for CP/IF treated patients, estimating autonomic abnormalities, associated with the HC development risk and its clinical course.

Changes of deceleration and acceleration capacity of heart rate in patients with acute hemispheric ischemic stroke.

PubMed

Xu, Yan-Hong; Wang, Xing-De; Yang, Jia-Jun; Zhou, Li; Pan, Yong-Chao

2016-01-01

Autonomic dysfunction is common after stroke, which is correlated with unfavorable outcome. Phase-rectified signal averaging is a newly developed technique for assessing cardiac autonomic function, by detecting sympathetic and vagal nerve activity separately through calculating acceleration capacity (AC) and deceleration capacity (DC) of heart rate. In this study, we used this technique for the first time to investigate the cardiac autonomic function of patients with acute hemispheric ischemic stroke. A 24-hour Holter monitoring was performed in 63 patients with first-ever acute ischemic stroke in hemisphere and sinus rhythm, as well as in 50 controls with high risk of stroke. DC, AC, heart rate variability parameters, standard deviation of all normal-to-normal intervals (SDNN), and square root of the mean of the sum of the squares of differences between adjacent normal-to-normal intervals (RMSSD) were calculated. The National Institutes of Health Stroke Scale (NIHSS) was used to assess the severity of stroke. We analyzed the changes of DC, AC, SDNN, and RMSSD and also studied the correlations between these parameters and NIHSS scores. The R-R (R wave to R wave on electrocardiogram) intervals, DC, AC, and SDNN in the cerebral infarction group were lower than those in controls (P=0.003, P=0.002, P=0.006, and P=0.043), but the difference of RMSSD and the D-value and ratio between absolute value of AC (|AC|) and DC were not statistically significant compared with those in controls. The DC of the infarction group was significantly correlated with |AC|, SDNN, and RMSSD (r=0.857, r=0.619, and r=0.358; P=0.000, P=0.000, and P=0.004). Correlation analysis also showed that DC, |AC|, and SDNN were negatively correlated with NIHSS scores (r=-0.279, r=-0.266, and r=-0.319; P=0.027, P=0.035, and P=0.011). Both DC and AC of heart rate decreased in patients with hemispheric infarction, reflecting a decrease in both vagal and sympathetic modulation. Both DC and AC were correlated with the severity of stroke.

Insulin sensitivity and cardiac autonomic function in young male practitioners of yoga.

PubMed

Chaya, M S; Ramakrishnan, G; Shastry, S; Kishore, R P; Nagendra, H; Nagarathna, R; Raj, T; Thomas, T; Vaz, M; Kurpad, A V

2008-01-01

While yoga is thought to reduce the risk of chronic non-communicable diseases such as diabetes, there are no studies on insulin sensitivity in long term practitioners of yoga. We assessed insulin sensitivity and cardiac autonomic function in long term practitioners of yoga. Fifteen healthy, young, male practitioners of yoga were compared with 15 young, healthy males who did not practice yoga matched for body-mass index. Fasting insulin sensitivity was measured in the fasting state by the hyperinsulinaemic-euglycaemic clamp. There were no significant differences between the groups in their anthropometry or body composition. However, the fasting plasma insulin was significantly lower in the yoga group. The yoga group was also more insulin sensitive (yoga 7.82 [2.29] v. control 4.86 [11.97] (mg/[kg.min])/(microU/ml), p < 0.001). While the body weight and waist circumference were negatively correlated with glucose disposal rate in the controls, there were no similar correlations in the yoga group. The yoga group had significantly higher low-frequency power and lower normalized high-frequency power. Long term yoga practice (for 1 year or more) is associated with increased insulin sensitivity and attenuates the negative relationship between body weight or waist circumference and insulin sensitivity.

Decreased baroreflex sensitivity is linked to the atherogenic index, retrograde inflammation, and oxidative stress in subclinical hypothyroidism.

PubMed

Syamsunder, Avupati Naga; Pal, Pravati; Pal, Gopal Krushna; Kamalanathan, Chandrakasan Sadishkumar; Parija, Subhash Chandra; Nanda, Nivedita; Sirisha, Allampalli

2017-02-01

Purpose/aim of the study: The present study investigated the link of hyperlipidemia, inflammation and oxidative stress (OS) to cardiovascular (CV) risks in subclinical hypothyroidism (SCH). We enrolled 81 subclinical hypothyroid patients and 80 healthy subjects as control. Their CV and autonomic functions were assessed by spectral analysis of heart rate variability (HRV), continuous blood pressure variability (BPV) measurement and conventional autonomic function testing. Thyroid profile, lipid profile, immunological, inflammatory and OS markers were estimated and correlated with the baro-reflex sensitivity (BRS), the marker of sympathovagal imbalance (SVI) & CV risk. Mean arterial pressure (MAP, P<0.0001), total peripheral resistance (TPR, P<0.0001), ratio of low-frequency to high-frequency power of HRV (LF-HF ratio) (P<0.0001) were significantly higher and BRS (P<0.0001) was significantly lower in SCH group than the control group. BRS significantly correlated with heart rate, MAP, LF-HF ratio, lipid risk factors, anti-thyroperoxidase antibody, thyroid-stimulating hormone, high-sensitive C-reactive protein (hsCRP), malondialdehyde (MDA) and SCH. It was concluded that SVI is associated with SCH. Though dyslipidemia, inflammation and OS contributed to decreased BRS, SCH per se contributed maximally to it. Decreased BRS could be a physiological basis of increased CV risks in patients with SCH.

When helping helps: autonomous motivation for prosocial behavior and its influence on well-being for the helper and recipient.

PubMed

Weinstein, Netta; Ryan, Richard M

2010-02-01

Self-determination theory posits that the degree to which a prosocial act is volitional or autonomous predicts its effect on well-being and that psychological need satisfaction mediates this relation. Four studies tested the impact of autonomous and controlled motivation for helping others on well-being and explored effects on other outcomes of helping for both helpers and recipients. Study 1 used a diary method to assess daily relations between prosocial behaviors and helper well-being and tested mediating effects of basic psychological need satisfaction. Study 2 examined the effect of choice on motivation and consequences of autonomous versus controlled helping using an experimental design. Study 3 examined the consequences of autonomous versus controlled helping for both helpers and recipients in a dyadic task. Finally, Study 4 manipulated motivation to predict helper and recipient outcomes. Findings support the idea that autonomous motivation for helping yields benefits for both helper and recipient through greater need satisfaction. Limitations and implications are discussed. Copyright 2009 APA, all rights reserved

Autonomic Nervous Activity and Lipid Oxidation Postexercise with Capsaicin in the Humans

PubMed Central

Yeo, Nam Hwoeh; Kang, Sunghwun

2010-01-01

This study evaluated the synergistic effects of acute exercise with capsaicin (200mg) upon the restoration of cardiac autonomic functions and depolarization- repolarization interval as well as substrate oxidation. Nine healthy males [21.9(0.8) yrs] volunteered for this study. Cardiac autonomic activity, metabolic responses, and the ECG QT intervals were continuously measured during 5 min at rest and postexercise recovery after 30 min exercise at 50% VO2max on a stationary ergometer with placebo (ECON) or capsaicin intake (ECAP), and no exercise control (NCON) were randomized. Results indicated that the HF power reflecting parasympathetic activity significantly returned to the baseline much faster during ECAP than ECON trial during postexercise [122.1 (23.2) vs. 60.2 (11.7) %, p < 0.05]. The ECAP trial significantly decreased RQ [0.79(0.02) vs. 0.85 (0.03), p < 0.05] with significantly greater fat oxidation [69.3 (6.0) vs. 49.4 (10.8) %, p < 0.05] in comparison to NCON trial during 120 min postexercise recovery without any adverse effects on cardiac electrical stability as determined by trigger-averaged ECG QT interval analyses. We suggest that capsaicin before the exercise may contribute to the improvement of cardio-protective functions and metabolic responses as one of the beneficial supplements accelerating faster restoration of autonomic activity and enhanced lipolysis during postexercise recovery without any adverse effects on cardiac electrical stability. Key points Capsaicin before exercise may contribute to the improvement of cardio-protective functions as one of the beneficial supplements accelerating faster restoration of autonomic activity Capsaicin before exercise enhanced lipolysis during postexercise recovery period Capsaicin intake does not influence cardiac electrical stability during recovery period. PMID:24149693

Cognitive load and autonomic response patterns under negative priming demand in depersonalization-derealization disorder.

PubMed

Lemche, Erwin; Sierra-Siegert, Mauricio; David, Anthony S; Phillips, Mary L; Gasston, David; Williams, Steven C R; Giampietro, Vincent P

2016-04-01

Previous studies have yielded evidence for cognitive processing abnormalities and alterations of autonomic functioning in depersonalization-derealization disorder (DPRD). However, multimodal neuroimaging and psychophysiology studies have not yet been conducted to test for functional and effective connectivity under cognitive stress in patients with DPRD. DPRD and non-referred control subjects underwent a combined Stroop/negative priming task, and the neural correlates of Stroop interference effect, negative priming effect, error rates, cognitive load span and average amplitude of skin conductance responses were ascertained for both groups. Evoked haemodynamic responses for basic Stroop/negative priming activations were compared. For basic Stroop to neutral contrast, patients with DPRD differed in the location (inferior vs. superior lobule) of the parietal region involved, but showed similar activations in the left frontal region. In addition, patients with DPRD also co-activated the dorsomedial prefrontal cortex (BA9) and posterior cingulate cortex (BA31), which were also found to be the main between-group difference regions. These regions furthermore showed connectivity with frequency of depersonalization states. Evoked haemodynamic responses drawn from regions of interest indicated significant between-group differences in 30-40% of time points. Brain-behaviour correlations differed mainly in laterality, yet only slightly in regions. A reversal of autonomic patterning became evident in patients with DPRD for cognitive load spans, indicating less effective arousal suppression under cognitive stress - patients with DPRD showed positive associations of cognitive load with autonomic responses, whereas controls exhibit respective inverse association. Overall, the results of the present study show only minor executive cognitive peculiarities, but further support the notion of abnormalities in autonomic functioning in patients with DPRD. © 2016 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

Autonomic composite hydrogels by reactive printing: materials and oscillatory response.

PubMed

Kramb, R C; Buskohl, P R; Slone, C; Smith, M L; Vaia, R A

2014-03-07

Autonomic materials are those that automatically respond to a change in environmental conditions, such as temperature or chemical composition. While such materials hold incredible potential for a wide range of uses, their implementation is limited by the small number of fully-developed material systems. To broaden the number of available systems, we have developed a post-functionalization technique where a reactive Ru catalyst ink is printed onto a non-responsive polymer substrate. Using a succinimide-amine coupling reaction, patterns are printed onto co-polymer or biomacromolecular films containing primary amine functionality, such as polyacrylamide (PAAm) or poly-N-isopropyl acrylamide (PNIPAAm) copolymerized with poly-N-(3-Aminopropyl)methacrylamide (PAPMAAm). When the films are placed in the Belousov-Zhabotinsky (BZ) solution medium, the reaction takes place only inside the printed nodes. In comparison to alternative BZ systems, where Ru-containing monomers are copolymerized with base monomers, reactive printing provides facile tuning of a range of hydrogel compositions, as well as enabling the formation of mechanically robust composite monoliths. The autonomic response of the printed nodes is similar for all matrices in the BZ solution concentrations examined, where the period of oscillation decreases in response to increasing sodium bromate or nitric acid concentration. A temperature increase reduces the period of oscillations and temperature gradients are shown to function as pace-makers, dictating the direction of the autonomic response (chemical waves).

Diagnosis of multiple system atrophy

PubMed Central

Palma, Jose-Alberto; Norcliffe-Kaufmann, Lucy; Kaufmann, Horacio

2017-01-01

Multiple system atrophy (MSA) may be difficult to distinguish clinically from other disorders, particularly in the early stages of the disease. An autonomic-only presentation can be indistinguishable from pure autonomic failure. Patients presenting with parkinsonism may be misdiagnosed as having Parkinson disease. Patients presenting with the cerebellar phenotype of MSA can mimic other adult-onset ataxias due to alcohol, chemotherapeutic agents, lead, lithium, and toluene, or vitamin E deficiency, as well as paraneoplastic, autoimmune, or genetic ataxias. A careful medical history and meticulous neurological examination remain the cornerstone for the accurate diagnosis of MSA. Ancillary investigations are helpful to support the diagnosis, rule out potential mimics, and define therapeutic strategies. This review summarizes diagnostic investigations useful in the differential diagnosis of patients with suspected MSA. Currently used techniques include structural and functional brain imaging, cardiac sympathetic imaging, cardiovascular autonomic testing, olfactory testing, sleep study, urological evaluation, and dysphagia and cognitive assessments. Despite advances in the diagnostic tools for MSA in recent years and the availability of consensus criteria for clinical diagnosis, the diagnostic accuracy of MSA remains sub-optimal. As other diagnostic tools emerge, including skin biopsy, retinal biomarkers, blood and cerebrospinal fluid biomarkers, and advanced genetic testing, a more accurate and earlier recognition of MSA should be possible, even in the prodromal stages. This has important implications as misdiagnosis can result in inappropriate treatment, patient and family distress, and erroneous eligibility for clinical trials of disease-modifying drugs. PMID:29111419

Cardiac Autonomic Regulation and Repolarization During Acute Experimental Hypoglycemia in Type 2 Diabetes

PubMed Central

Chow, Elaine; Bernjak, Alan; Walkinshaw, Emma; Lubina-Solomon, Alexandra; Freeman, Jenny; Macdonald, Ian A.; Sheridan, Paul J.

2017-01-01

Hypoglycemia is associated with increased cardiovascular mortality in trials of intensive therapy in type 2 diabetes mellitus (T2DM). We previously observed an increase in arrhythmias during spontaneous prolonged hypoglycemia in patients with T2DM. We examined changes in cardiac autonomic function and repolarization during sustained experimental hypoglycemia. Twelve adults with T2DM and 11 age- and BMI-matched control participants without diabetes underwent paired hyperinsulinemic clamps separated by 4 weeks. Glucose was maintained at euglycemia (6.0 mmol/L) or hypoglycemia (2.5 mmol/L) for 1 h. Heart rate, blood pressure, and heart rate variability were assessed every 30 min and corrected QT intervals and T-wave morphology every 60 min. Heart rate initially increased in participants with T2DM but then fell toward baseline despite maintained hypoglycemia at 1 h accompanied by reactivation of vagal tone. In control participants, vagal tone remained depressed during sustained hypoglycemia. Participants with T2DM exhibited greater heterogeneity of repolarization during hypoglycemia as demonstrated by T-wave symmetry and principal component analysis ratio compared with control participants. Epinephrine levels during hypoglycemia were similar between groups. Cardiac autonomic regulation during hypoglycemia appears to be time dependent. Individuals with T2DM demonstrate greater repolarization abnormalities for a given hypoglycemic stimulus despite comparable sympathoadrenal responses. These mechanisms could contribute to arrhythmias during clinical hypoglycemic episodes. PMID:28137792

Short-term supervised inpatient physiotherapy exercise protocol improves cardiac autonomic function after coronary artery bypass graft surgery--a randomised controlled trial.

PubMed

Mendes, Renata Gonçalves; Simões, Rodrigo Polaquini; De Souza Melo Costa, Fernando; Pantoni, Camila Bianca Falasco; Di Thommazo, Luciana; Luzzi, Sérgio; Catai, Aparecida Maria; Arena, Ross; Borghi-Silva, Audrey

2010-01-01

Coronary artery bypass grafting (CABG) is accompanied by severe impairment of cardiac autonomous regulation (CAR). This study aimed to determine whether a short-term physiotherapy exercise protocol post-CABG, during inpatient cardiac rehabilitation (CR), might improve CAR. Seventy-four patients eligible for CABG were recruited and randomised into physiotherapy exercise group (EG) or physiotherapy usual care group (UCG). EG patients underwent a short-term supervised inpatient physiotherapy exercise protocol consisting of an early mobilisation with progressive exercises plus usual care (respiratory exercises). UCG only received respiratory exercises. Forty-seven patients (24 EG and 23 UGC) completed the study. Outcome measures of CAR included linear and non-linear measures of heart rate variability (HRV) assessed before discharge. By hospital discharge, EG presented significantly higher parasympathetic HRV values [rMSSD, high frequency (HF), SD1)], global power (STD RR, SD2), non-linear HRV indexes [detrended fluctuation analysis (DFA)alpha1, DFAalpha2, approximate entropy (ApEn)] and mean RR compared to UCG (p<0.05). Conversely, higher values of mean HR, low frequency (LF) (sympathetic activity) and the LF/HF (global sympatho-vagal balance) were found in the UCG. A short-term supervised physiotherapy exercise protocol during inpatient CR improves CAR at the time of discharge. Thus, exercise-based inpatient CR might be an effective non-pharmacological tool to improve autonomic cardiac tone in patient's post-CABG.

Sudarshan Kriya Yoga improves cardiac autonomic control in patients with anxiety-depression disorders.

PubMed

Toschi-Dias, Edgar; Tobaldini, Eleonora; Solbiati, Monica; Costantino, Giorgio; Sanlorenzo, Roberto; Doria, Stefania; Irtelli, Floriana; Mencacci, Claudio; Montano, Nicola

2017-05-01

Several studies have demonstrated that adjuvant therapies as exercise and breathing training are effective in improving cardiac autonomic control (CAC) in patients with affective spectrum disorders. However, the effects of Sudarshan Kriya Yoga (SKY) on autonomic function in this population is unknown. Our objective was to test the hypothesis that SKY training improves CAC and cardiorespiratory coupling in patients with anxiety and/or depression disorders. Forty-six patients with a diagnosis of anxiety and/or depression disorders (DSM-IV) were consecutively enrolled and divided in two groups: 1) conventional therapy (Control) and 2) conventional therapy associated with SKY (Treatment) for 15 days. Anxiety and depression levels were determined using quantitative questionnaires. For the assessment of CAC and cardiorespiratory coupling, cardiorespiratory traces were analyzed using monovariate and bivariate autoregressive spectral analysis, respectively. After 15-days, we observed a reduction of anxiety and depression levels only in Treatment group. Moreover, sympathetic modulation and CAC were significantly lower while parasympathetic modulation and cardiorespiratory coupling were significantly higher in the Treatment compared to Control group. Intensive breathing training using SKY approach improves anxiety and/or depressive disorders as well as CAC and cardiorespiratory coupling. These finding suggest that the SKY training may be a useful non-pharmacological intervention to improve symptoms and reduce cardiovascular risk in patients with anxiety/depression disorders. Copyright © 2017 Elsevier B.V. All rights reserved.

Prediction of atrial fibrillation recurrence after cardioversion-interaction analysis of cardiac autonomic regulation.

PubMed

Seeck, A; Rademacher, W; Fischer, C; Haueisen, J; Surber, R; Voss, A

2013-03-01

Today atrial fibrillation (AF) is the most common cardiac arrhythmia in clinical practice accounting for approximately one third of hospitalizations and accompanied with a 5 fold increased risk for ischemic stroke and a 1.5 fold increased mortality risk. The role of the cardiac regulation system in AF recurrence after electrical cardioversion (CV) is still unclear. The aim of this study was to investigate the autonomic regulation by analyzing the interaction between heart rate and blood pressure using novel methods of nonlinear interaction dynamics, namely joint symbolic dynamics (JSD) and segmented Poincaré plot analysis (SPPA). For the first time, we applied SPPA to analyze the interaction between two time series. Introducing a parameter set of two indices, one derived from JSD and one from SPPA, the linear discriminant function analysis revealed an overall accuracy of 89% (sensitivity 91.7%, specificity 86.7%) for the classification between patients with stable sinus rhythm (group SR, n = 15) and with AF recurrence (group REZ, n = 12). This study proves that the assessment of the autonomic regulation by analyzing the coupling of heart rate and systolic blood pressure provides a potential tool for the prediction of AF recurrence after CV and could aid in the adjustment of therapeutic options for patients with AF. Copyright © 2012 IPEM. Published by Elsevier Ltd. All rights reserved.

Manifestations of Parkinson disease differ in association with REM sleep behavior disorder.

PubMed

Postuma, Ronald B; Gagnon, Jean-Francois; Vendette, Melanie; Charland, Katia; Montplaisir, Jacques

2008-09-15

REM sleep behavior disorder (RBD) is commonly associated with Parkinson disease (PD), but it is unclear whether this association has implications for disease manifestations. We evaluated 36 PD patients for the presence of RBD by polysomnography. Patients underwent an extensive evaluation by a movement disorders specialist blinded to polysomnography results. Severity of motor manifestations, autonomic, visual, psychiatric, and olfactory dysfunctions and quality of life (QOL) were assessed, and compared using regression analysis that adjusted for disease duration, age and sex. Severity of motor manifestations did not differ between groups. However, the presence of RBD in PD was strongly associated with symptoms and signs of orthostatic hypotension (systolic blood pressure lying to standing = -25.7 +/- 13.0 mmHg vs. -4.9 +/-14.1, P < 0.001); and orthostatic symptom prevalence = 71% vs. 27%, P = 0.0076). There was no association between RBD and other autonomic symptoms. Color vision was worse in patients with RBD, but olfactory dysfunction did not differ between groups. The prevalence of depression, hallucinations, paranoia, and impulse disorders did not differ between groups. Emotional functioning and general health QOL measures were lower in those with RBD, but there were no differences between groups on disease-specific indices or on measures of overall physical QOL. These findings suggest that the pathophysiology of RBD and nonmotor manifestations of PD, particularly autonomic dysfunction, are linked. (c) 2007 Movement Disorder Society.

Effects of prefrontal rTMS on autonomic reactions to affective pictures.

PubMed

Berger, Christoph; Domes, Gregor; Balschat, Johannes; Thome, Johannes; Höppner, Jacqueline

2017-02-01

Repetitive transcranial magnetic stimulation (rTMS) can modulate the excitability of stimulated cortical areas, such as prefrontal areas involved in emotion regulation. Low frequency (LF) rTMS is expected to have inhibitory effects on prefrontal regions, and thereby should disinhibit limbic activity, resulting in enhanced emotional and autonomic reactions. For high frequency (HF) rTMS, the opposite pattern might be assumed. The objective of this study was to determine the effects of different rTMS frequencies applied to the right dlPFC on autonomic functions and on emotional perception. In a crossover design, two groups of 20 healthy young women were either stimulated with one session of LF rTMS (1 Hz) or one session of HF rTMS (10 Hz), compared to sham stimulation. We assessed phasic cardiac responses (PCR), skin conductance reactions (SCR), and emotional appraisal of emotional pictures as well as recognition memory after each rTMS application. After LF rTMS, PCR (heart rate deceleration) during presentation of pictures with negative and neutral valence was significantly increased compared to the presentation of positive pictures. In contrast, the modulatory effect of picture valence and arousal on the cardiac orienting response was absent after HF rTMS. Our results suggest that frontal LF rTMS indirectly activates the ANS via inhibition of the right dlPFC activity, likely by enhancing the sensory processing or attention to aversive and neutral stimuli.

Autonomic, functional, skeletal muscle, and cardiac abnormalities are associated with increased ergoreflex sensitivity in mitochondrial disease.

PubMed

Giannoni, Alberto; Aimo, Alberto; Mancuso, Michelangelo; Piepoli, Massimo Francesco; Orsucci, Daniele; Aquaro, Giovanni Donato; Barison, Andrea; De Marchi, Daniele; Taddei, Claudia; Cameli, Matteo; Raglianti, Valentina; Siciliano, Gabriele; Passino, Claudio; Emdin, Michele

2017-12-01

Mitochondrial disease (MD) is a genetic disorder affecting skeletal muscles, with possible myocardial disease. The ergoreflex, sensitive to skeletal muscle work, regulates ventilatory and autonomic responses to exercise. We hypothesized the presence of an increased ergoreflex sensitivity in MD patients, its association with abnormal ventilatory and autonomic responses, and possibly with subclinical cardiac involvement. Twenty-five MD patients (aged 46 ± 3 years, 32% male) with skeletal myopathy but without known cardiac disease, underwent a thorough evaluation including BNPs, galectin-3, soluble suppression of tumorigenesis 2 (sST2), high sensitivity troponin T/I, catecholamines, ECG, 24-h ECG recording, cardiopulmonary exercise testing, echocardiography, cardiac/muscle magnetic resonance (C/MMR), and ergoreflex assessment. Thirteen age- and sex-matched healthy controls were chosen. Among these myopathic patients, subclinical cardiac damage was detected in up to 80%, with 44% showing fibrosis at CMR. Ergoreflex sensitivity was markedly higher in patients than in controls (64% vs. 37%, P < 0.001), and correlated with muscle fat to water ratio and extracellular volume at MMR (both P < 0.05). Among patients, ergoreflex sensitivity was higher in those with cardiac involvement (P = 0.034). Patients showed a lower peak oxygen consumption (VO 2 /kg) than controls (P < 0.001), as well as ventilatory inefficiency (P = 0.024). Ergoreflex sensitivity correlated with reduced workload and peak VO 2 /kg (both P < 0.001), and several indicators of autonomic imbalance (P < 0.05). Plasma norepinephrine was the unique predictor of myocardial fibrosis at univariate analysis (P < 0.05). Skeletal myopathy in MD is characterized by enhanced ergoreflex sensitivity, which is associated with a higher incidence of cardiac involvement, exercise intolerance, and sympathetic activation. © 2017 The Authors. European Journal of Heart Failure © 2017 European Society of Cardiology.

Autonomic Dysfunction Correlates with Clinical and Inflammatory Activity in Patients with Crohn's Disease.

PubMed

Engel, Tal; Ben-Horin, Shomron; Beer-Gabel, Marc

2015-10-01

Autonomic dysfunction has been implicated in Crohn's disease (CD). We aimed to investigate heart rate variability (HRV) as a marker of possible autonomic imbalance in patients with CD. Thirty patients with CD and 30 age- and gender-matched healthy controls were enrolled in a prospective cohort study and underwent HRV study. Anxiety level was scored using the STAI questionnaire and CD clinical activity was assessed by Harvey-Bradshaw index. Blood tests including inflammatory markers were obtained for all participants. CD subjects had lower mean blood pressure (85.51 ± 11.07 mm Hg, 91.51 ± 6.99, P = 0.015) and albumin and significantly higher CRP and IL-6 compared with controls (P < 0.002 for all comparisons). Mean HRV values of very low-frequency power and low-frequency power components were significantly lower among CD subjects (P = 0.038 and 0.027, respectively), implying a predominant sympathetic tone. Anxiety level scores were significantly higher among patients with CD for both state anxiety (P = 0.001) and trait anxiety (P < 0.0001). However, patients with active disease had similar anxiety scores as patients in remission, yet had a significantly lower BMI, lower albumin level, and higher CRP and IL-6 levels (P < 0.05 for all comparisons). Moreover, despite similar anxiety scores, patients with active disease had higher pulse rate (P = 0.02) and lower HRV indexes, which correlated with albumin levels(r = 0.7, P = 0.001). Although patients with CD have higher anxiety levels compared with controls, they exhibit depressed HRV independent of this anxiety state and in direct correlation with disease activity and inflammatory markers. These observations suggest an inherent imbalance of autonomic function associated with active inflammation.

Autonomic Cluster Management System (ACMS): A Demonstration of Autonomic Principles at Work

NASA Technical Reports Server (NTRS)

Baldassari, James D.; Kopec, Christopher L.; Leshay, Eric S.; Truszkowski, Walt; Finkel, David

2005-01-01

Cluster computing, whereby a large number of simple processors or nodes are combined together to apparently function as a single powerful computer, has emerged as a research area in its own right. The approach offers a relatively inexpensive means of achieving significant computational capabilities for high-performance computing applications, while simultaneously affording the ability to. increase that capability simply by adding more (inexpensive) processors. However, the task of manually managing and con.guring a cluster quickly becomes impossible as the cluster grows in size. Autonomic computing is a relatively new approach to managing complex systems that can potentially solve many of the problems inherent in cluster management. We describe the development of a prototype Automatic Cluster Management System (ACMS) that exploits autonomic properties in automating cluster management.

SED16 autonomous star tracker night sky testing

NASA Astrophysics Data System (ADS)

Foisneau, Thierry; Piriou, Véronique; Perrimon, Nicolas; Jacob, Philippe; Blarre, Ludovic; Vilaire, Didier

2017-11-01

The SED16 is an autonomous multi-missions star tracker which delivers three axis satellite attitude in an inertial reference frame and the satellite angular velocity with no prior information. The qualification process of this star sensor includes five validation steps using optical star simulator, digitized image simulator and a night sky tests setup. The night sky testing was the final step of the qualification process during which all the functions of the star tracker were used in almost nominal conditions : Autonomous Acquisition of the attitude, Autonomous Tracking of ten stars. These tests were performed in Calern in the premises of the OCA (Observatoire de la Cote d'Azur). The test set-up and the test results are described after a brief review of the sensor main characteristics and qualification process.

Autonomy Support, Need Satisfaction, and Motivation for Support Among Adults With Intellectual Disability: Testing a Self-Determination Theory Model.

PubMed

Frielink, Noud; Schuengel, Carlo; Embregts, Petri J C M

2018-01-01

The tenets of self-determination theory as applied to support were tested with structural equation modelling for 186 people with ID with a mild to borderline level of functioning. The results showed that (a) perceived autonomy support was positively associated with autonomous motivation and with satisfaction of need for autonomy, relatedness, and competence; (b) autonomous motivation and need satisfaction were associated with higher psychological well-being; (c) autonomous motivation and need satisfaction statistically mediated the association between autonomy support and well-being; and (d) satisfaction of need for autonomy and relatedness was negatively associated with controlled motivation, whereas satisfaction of need for relatedness was positively associated with autonomous motivation. The self-determination theory provides insights relevant for improving support for people with intellectual disability.

Orthostatic Hypotension: A Practical Approach to Investigation and Management.

PubMed

Arnold, Amy C; Raj, Satish R

2017-12-01

The maintenance of blood pressure upon the assumption of upright posture depends on rapid cardiovascular adaptations driven primarily by the autonomic nervous system. Failure of these compensatory mechanisms can result in orthostatic hypotension (OH), defined as sustained reduction in systolic blood pressure > 20 mm Hg or diastolic blood pressure > 10 mm Hg within 3 minutes of standing or > 60° head-up tilt. OH is a common finding, particularly in elderly populations, associated with cardiovascular and cerebrovascular morbidity and mortality. Therefore, it is important to identify OH in the clinical setting. The detection of OH requires blood pressure measurements in the supine and standing positions. A more practical approach in clinics might be measurement of seated and standing blood pressure, but this can produce smaller depressor responses because of reduced gravitational stress. Heart rate responses to standing should be concomitantly measured to assess integrity of baroreflex function. Patients with OH can present with symptoms of cerebral hypoperfusion on standing predisposing to syncope and falls; however, many patients are asymptomatic. When the diagnosis of OH is established, it is important to document potentially deleterious medications and comorbidities and to assess for neurogenic autonomic impairment to establish underlying causes. Treatment should be initiated in a structured and stepwise approach starting with nonpharmacological interventions (eg, lifestyle modifications and physical countermanoeuvres), and adding pharmacological interventions as needed in patients with severe OH (eg, midodrine, droxidopa, fludrocortisone). The treatment goal in OH should be to improve symptoms and functional status, and not to target arbitrary blood pressure values. Copyright © 2017 Canadian Cardiovascular Society. Published by Elsevier Inc. All rights reserved.

Evidence for aerobic exercise training on the autonomic function in patients with chronic obstructive pulmonary disease (COPD): a systematic review.

PubMed

Mohammed, Jibril; Derom, Eric; Van Oosterwijck, Jessica; Da Silva, Hellen; Calders, Patrick

2018-03-01

To assess evidence for the effectiveness of aerobic exercise training (AET) on the autonomic function (AF) outcomes in patients with chronic obstructive pulmonary disease (COPD). Online databases of PubMed, CINAHL and Web of Science were systematically searched for all years till 26th of January, 2017. Clinical studies assessing any measure of AF following exercise training in patients with COPD were included. Data were extracted from studies with high methodological quality for evidence synthesis. Rating of evidence quality was determined using the GRADE guidelines. The Majority of the included studies utilized continuous exercise training mode with a vigorous level of intensity. Each exercise training session lasted between 30 to 40minutes, and the frequency of intervention was ≥3 times/week. Evidence synthesis of studies with high methodological quality revealed that a high quality evidence level supported a significant increase for time-domain heart rate variability (HRV) analyses and the heart rate recovery (HRR) following AET. The review also found that frequency domain HRV analyses were not significantly affected by AET. The evidence to support the effect of exercise training on baroreceptor sensitivity (BRS) in patients with COPD is very low. Aerobic exercise training demonstrated beneficial but limited effects on the AF in COPD. Presently, it is not clear whether these effects are sustained in the long term. Only a limited number of RCTs were available indicating a significant gap in the literature. Copyright © 2017 Chartered Society of Physiotherapy. Published by Elsevier Ltd. All rights reserved.

The Use of Software Agents for Autonomous Control of a DC Space Power System

NASA Technical Reports Server (NTRS)

May, Ryan D.; Loparo, Kenneth A.

2014-01-01

In order to enable manned deep-space missions, the spacecraft must be controlled autonomously using on-board algorithms. A control architecture is proposed to enable this autonomous operation for an spacecraft electric power system and then implemented using a highly distributed network of software agents. These agents collaborate and compete with each other in order to implement each of the control functions. A subset of this control architecture is tested against a steadystate power system simulation and found to be able to solve a constrained optimization problem with competing objectives using only local information.

Gas House Autonomous System Monitoring

NASA Technical Reports Server (NTRS)

Miller, Luke; Edsall, Ashley

2015-01-01

Gas House Autonomous System Monitoring (GHASM) will employ Integrated System Health Monitoring (ISHM) of cryogenic fluids in the High Pressure Gas Facility at Stennis Space Center. The preliminary focus of development incorporates the passive monitoring and eventual commanding of the Nitrogen System. ISHM offers generic system awareness, adept at using concepts rather than specific error cases. As an enabler for autonomy, ISHM provides capabilities inclusive of anomaly detection, diagnosis, and abnormality prediction. Advancing ISHM and Autonomous Operation functional capabilities enhances quality of data, optimizes safety, improves cost effectiveness, and has direct benefits to a wide spectrum of aerospace applications.

Long commuting time, extensive overtime, and sympathodominant state assessed in terms of short-term heart rate variability among male white-collar workers in the Tokyo megalopolis.

PubMed

Kageyama, T; Nishikido, N; Kobayashi, T; Kurokawa, Y; Kaneko, T; Kabuto, M

1998-07-01

To investigate the possible effects of long commuting time and extensive overtime on daytime cardiac autonomic activity, the short-term heart rate variability (HRV) both at supine rest and at standing rest of 223 male white-collar workers in the Tokyo Megalopolis was examined. Workers with a one-way commute of 90 min or more exhibited decreased vagal activity at supine rest and increased sympathetic activity regardless of posture, and those doing overtime of 60 h/month or more exhibited decreased vagal activity and increased sympathetic activity at standing rest. These findings suggest that chronic stress or fatigue resulting from long commuting time or extensive overtime caused these individuals to be in a sympathodominant state. Although these shifts in autonomic activities are not direct indicators of disease, it can be hypothesized that they can induce cardiovascular abnormalities or dysfunctions related to the onset of heart disease. Assessment of the daily and weekly variations in HRV as a function of daily life activities (such as working, commuting, sleeping, and exercising) among workers in Asia-Pacific urban areas might be one way of studying the possible effects of long commuting time, and extensive overtime, on health.

The dependency paradox in close relationships: accepting dependence promotes independence.

PubMed

Feeney, Brooke C

2007-02-01

Using multiple methods, this investigation tested the hypothesis that a close relationship partner's acceptance of dependence when needed (e.g., sensitive responsiveness to distress cues) is associated with less dependence, more autonomous functioning, and more self-sufficiency (as opposed to more dependence) on the part of the supported individual. In two studies, measures of acceptance of dependency needs and independent functioning were obtained through couple member reports, by observing couple members' behaviors during laboratory interactions, by observing responses to experimentally manipulated partner assistance provided during an individual laboratory task, and by following couples over a period of 6 months to examine independent goal striving as a function of prior assessments of dependency acceptance. Results provided converging evidence in support of the proposed hypothesis. Implications of the importance of close relationships for optimal individual functioning are discussed. ((c) 2007 APA, all rights reserved).

AUTONOMOUS AND NONAUTONOMOUS REGULATION OF WNT-MEDIATED NEURONAL POLARITY BY THE C. ELEGANS ROR KINASE CAM-1

PubMed Central

Chien, Shih-Chieh Jason; Gurling, Mark; Kim, Changsung; Craft, Teresa; Forrester, Wayne; Garriga, Gian

2015-01-01

Wnts are a conserved family of secreted glycoproteins that regulate various developmental processes in metazoans. Three of the five C. elegans Wnts, CWN-1, CWN-2 and EGL-20, and the sole Wnt receptor of the Ror kinase family, CAM-1, are known to regulate the anterior polarization of the mechanosensory neuron ALM. Here we show that CAM-1 and the Frizzled receptor MOM-5 act in parallel pathways to control ALM polarity. We also show that CAM-1 has two functions in this process: an autonomous signaling function that promotes anterior polarization and a nonautonomous Wnt-antagonistic function that inhibits anterior polarization. These antagonistic activities can account for the weak ALM phenotypes displayed by cam-1 mutants. Our observations suggest that CAM-1 could function as a Wnt receptor in many developmental processes, but the analysis of cam-1 mutants may fail to reveal CAM-1’s role as a receptor in these processes because of its Wnt-antagonistic activity. In this model, loss of CAM-1 results in increased levels of Wnts that act through other Wnt receptors, masking CAM-1’s autonomous role as a Wnt receptor. PMID:25917219

Automation of orbit determination functions for National Aeronautics and Space Administration (NASA)-supported satellite missions

NASA Technical Reports Server (NTRS)

Mardirossian, H.; Beri, A. C.; Doll, C. E.

1990-01-01

The Flight Dynamics Facility (FDF) at Goddard Space Flight Center (GSFC) provides spacecraft trajectory determination for a wide variety of National Aeronautics and Space Administration (NASA)-supported satellite missions, using the Tracking Data Relay Satellite System (TDRSS) and Ground Spaceflight and Tracking Data Network (GSTDN). To take advantage of computerized decision making processes that can be used in spacecraft navigation, the Orbit Determination Automation System (ODAS) was designed, developed, and implemented as a prototype system to automate orbit determination (OD) and orbit quality assurance (QA) functions performed by orbit operations. Based on a machine-resident generic schedule and predetermined mission-dependent QA criteria, ODAS autonomously activates an interface with the existing trajectory determination system using a batch least-squares differential correction algorithm to perform the basic OD functions. The computational parameters determined during the OD are processed to make computerized decisions regarding QA, and a controlled recovery process is activated when the criteria are not satisfied. The complete cycle is autonomous and continuous. ODAS was extensively tested for performance under conditions resembling actual operational conditions and found to be effective and reliable for extended autonomous OD. Details of the system structure and function are discussed, and test results are presented.

Automation of orbit determination functions for National Aeronautics and Space Administration (NASA)-supported satellite missions

NASA Technical Reports Server (NTRS)

Mardirossian, H.; Heuerman, K.; Beri, A.; Samii, M. V.; Doll, C. E.

1989-01-01

The Flight Dynamics Facility (FDF) at Goddard Space Flight Center (GSFC) provides spacecraft trajectory determination for a wide variety of National Aeronautics and Space Administration (NASA)-supported satellite missions, using the Tracking Data Relay Satellite System (TDRSS) and Ground Spaceflight and Tracking Data Network (GSTDN). To take advantage of computerized decision making processes that can be used in spacecraft navigation, the Orbit Determination Automation System (ODAS) was designed, developed, and implemented as a prototype system to automate orbit determination (OD) and orbit quality assurance (QA) functions performed by orbit operations. Based on a machine-resident generic schedule and predetermined mission-dependent QA criteria, ODAS autonomously activates an interface with the existing trajectory determination system using a batch least-squares differential correction algorithm to perform the basic OD functions. The computational parameters determined during the OD are processed to make computerized decisions regarding QA, and a controlled recovery process isactivated when the criteria are not satisfied. The complete cycle is autonomous and continuous. ODAS was extensively tested for performance under conditions resembling actual operational conditions and found to be effective and reliable for extended autonomous OD. Details of the system structure and function are discussed, and test results are presented.

Current challenges in autonomous vehicle development

NASA Astrophysics Data System (ADS)

Connelly, J.; Hong, W. S.; Mahoney, R. B., Jr.; Sparrow, D. A.

2006-05-01

The field of autonomous vehicles is a rapidly growing one, with significant interest from both government and industry sectors. Autonomous vehicles represent the intersection of artificial intelligence (AI) and robotics, combining decision-making with real-time control. Autonomous vehicles are desired for use in search and rescue, urban reconnaissance, mine detonation, supply convoys, and more. The general adage is to use robots for anything dull, dirty, dangerous or dumb. While a great deal of research has been done on autonomous systems, there are only a handful of fielded examples incorporating machine autonomy beyond the level of teleoperation, especially in outdoor/complex environments. In an attempt to assess and understand the current state of the art in autonomous vehicle development, a few areas where unsolved problems remain became clear. This paper outlines those areas and provides suggestions for the focus of science and technology research. The first step in evaluating the current state of autonomous vehicle development was to develop a definition of autonomy. A number of autonomy level classification systems were reviewed. The resulting working definitions and classification schemes used by the authors are summarized in the opening sections of the paper. The remainder of the report discusses current approaches and challenges in decision-making and real-time control for autonomous vehicles. Suggested research focus areas for near-, mid-, and long-term development are also presented.

A Briefing on Metrics and Risks for Autonomous Decision-Making in Aerospace Applications

NASA Technical Reports Server (NTRS)

Frost, Susan; Goebel, Kai Frank; Galvan, Jose Ramon

2012-01-01

Significant technology advances will enable future aerospace systems to safely and reliably make decisions autonomously, or without human interaction. The decision-making may result in actions that enable an aircraft or spacecraft in an off-nominal state or with slightly degraded components to achieve mission performance and safety goals while reducing or avoiding damage to the aircraft or spacecraft. Some key technology enablers for autonomous decision-making include: a continuous state awareness through the maturation of the prognostics health management field, novel sensor development, and the considerable gains made in computation power and data processing bandwidth versus system size. Sophisticated algorithms and physics based models coupled with these technological advances allow reliable assessment of a system, subsystem, or components. Decisions that balance mission objectives and constraints with remaining useful life predictions can be made autonomously to maintain safety requirements, optimal performance, and ensure mission objectives. This autonomous approach to decision-making will come with new risks and benefits, some of which will be examined in this paper. To start, an account of previous work to categorize or quantify autonomy in aerospace systems will be presented. In addition, a survey of perceived risks in autonomous decision-making in the context of piloted aircraft and remotely piloted or completely autonomous unmanned autonomous systems (UAS) will be presented based on interviews that were conducted with individuals from industry, academia, and government.

Alzheimer's Disease: The Role of Microglia in Brain Homeostasis and Proteopathy

PubMed Central

Clayton, Kevin A.; Van Enoo, Alicia A.; Ikezu, Tsuneya

2017-01-01

Brain aging is central to late-onset Alzheimer's disease (LOAD), although the mechanisms by which it occurs at protein or cellular levels are not fully understood. Alzheimer's disease is the most common proteopathy and is characterized by two unique pathologies: senile plaques and neurofibrillary tangles, the former accumulating earlier than the latter. Aging alters the proteostasis of amyloid-β peptides and microtubule-associated protein tau, which are regulated in both autonomous and non-autonomous manners. Microglia, the resident phagocytes of the central nervous system, play a major role in the non-autonomous clearance of protein aggregates. Their function is significantly altered by aging and neurodegeneration. This is genetically supported by the association of microglia-specific genes, TREM2 and CD33, and late onset Alzheimer's disease. Here, we propose that the functional characterization of microglia, and their contribution to proteopathy, will lead to a new therapeutic direction in Alzheimer's disease research. PMID:29311768

Anesthesia and concussion.

PubMed

Tasker, Robert C

2017-06-01

As clinicians preparing patients for general anesthesia, should we consider the possibility of concussion in our elective operative patients? If so, why is this necessary? Is it possible that exposure to an anesthetic is detrimental to recovery from concussion? If so, what should we do about the imperative/urgency for surgery? No answers are promised in this review. Rather, the focus is on the questions and approaches taken in the recent literature, as well as highlighting a need for more research. Surgery, pain and general anesthesia all influence autonomic nervous system responses. Intravenous and inhalational anesthetic agents are also known to have variable effects on the cerebrovascular reactivity (CVR) to carbon dioxide (CO2). This review adds to this general information the recent, specific physiologic alterations seen after concussion in autonomic system function and the CVR to CO2. This review provides a perspective about autonomic nervous system function and cerebrovascular effects of concussion, and some relevant clinical issues that warrant further clinical study.

IDEA: Planning at the Core of Autonomous Reactive Agents

NASA Technical Reports Server (NTRS)

Muscettola, Nicola; Dorais, Gregory A.; Fry, Chuck; Levinson, Richard; Plaunt, Christian; Clancy, Daniel (Technical Monitor)

2002-01-01

Several successful autonomous systems are separated into technologically diverse functional layers operating at different levels of abstraction. This diversity makes them difficult to implement and validate. In this paper, we present IDEA (Intelligent Distributed Execution Architecture), a unified planning and execution framework. In IDEA a layered system can be implemented as separate agents, one per layer, each representing its interactions with the world in a model. At all levels, the model representation primitives and their semantics is the same. Moreover, each agent relies on a single model, plan database, plan runner and on a variety of planners, both reactive and deliberative. The framework allows the specification of agents that operate, within a guaranteed reaction time and supports flexible specification of reactive vs. deliberative agent behavior. Within the IDEA framework we are working to fully duplicate the functionalities of the DS1 Remote Agent and extend it to domains of higher complexity than autonomous spacecraft control.

Trajectory generation for an on-road autonomous vehicle

NASA Astrophysics Data System (ADS)

Horst, John; Barbera, Anthony

2006-05-01

We describe an algorithm that generates a smooth trajectory (position, velocity, and acceleration at uniformly sampled instants of time) for a car-like vehicle autonomously navigating within the constraints of lanes in a road. The technique models both vehicle paths and lane segments as straight line segments and circular arcs for mathematical simplicity and elegance, which we contrast with cubic spline approaches. We develop the path in an idealized space, warp the path into real space and compute path length, generate a one-dimensional trajectory along the path length that achieves target speeds and positions, and finally, warp, translate, and rotate the one-dimensional trajectory points onto the path in real space. The algorithm moves a vehicle in lane safely and efficiently within speed and acceleration maximums. The algorithm functions in the context of other autonomous driving functions within a carefully designed vehicle control hierarchy.

Biological correlates of direct exposure to terrorism several years postdisaster.

PubMed

Tucker, Phebe; Pfefferbaum, Betty; North, Carol S; Kent, Adrian; Jeon-Slaughter, Haekyung; Parker, Don E

2010-08-01

It is important to understand long-term biological and psychiatric correlates of intense exposure to terrorism. We assessed psychiatric diagnoses and biological stress measures in 50 healthy, highly exposed Oklahoma City bombing survivors recruited from a bombing registry 6 1/2 to 7 years postdisaster, comparing them with demographically matched, nonexposed community members. The Diagnostic Interview Schedule (DIS) determined Axis I psychiatric diagnoses. Participants' salivary cortisol levels were obtained at 8 am, and physiologic assessment measured participants' heart rate and blood pressure responses to a bombing-related interview. Eleven survivors with posttraumatic stress disorder (PTSD) had significantly higher cortisol levels than did both non-PTSD survivors and controls. Survivors with and without PTSD did not differ in any autonomic reactivity measure, whereas the total survivor group had significantly higher reactivity than controls in all measures. Positive correlations occurred between several autonomic reactivity measures, but none between cortisol and autonomic measures. Results differentiate the autonomic and cortisol systems relative to terrorism exposure. Findings support research associating PTSD with hypothalamic-pituitary-adrenal (HPA) axis changes, whereas autonomic reactivity appeared to be a more generalized trauma response. Correlation statistics substantiated a lack of connection between the 2 biological systems. Follow-up could elucidate the long-term course of these stress systems and eventual health status in survivors, in view of the medical morbidity noted in PTSD studies.