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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
41

Autonomic Nervous System Functioning in Posttraumatic Stress Disorder at Rest and During Stress: The Role of the Parasympathetic Nervous System

Keary, Therese A. 26 August 2008 (has links)
No description available.
42

Testing emotion regulation and parasympathetic nervous system deficits as a mechanism for the transmission of borderline personality disorder

Richmond, Julia R. 06 June 2017 (has links)
No description available.
43

Psychophysiological distinctions in emotional responding: sensitivity to perceiving loss of connection

Seah, Lily 10 May 2023 (has links)
The study investigated how distinctions in perception might affect emotional responding to a change in an affordance. There is evidence that Europeans tend to perceive salient objects in the foreground, while East Asians tend to perceive holistically. Due to sensitivity to focal objects, European Americans (EA) were hypothesized to respond negatively with increased HR variance on perceiving loss of connection when playing Cyberball. EA would also feel sadness more intensely, in terms of decreased heart rate and increased RSA, at an earlier time during a sad clip. Chinese Americans (CA) were predicted to show no difference in affect from controls. ECG, fEMG, respiration and self-report data were acquired from 51 subjects (38 EA, 13 CA, 25 male, mean age 21.1) in a between-subjects design. 26 subjects (19 EA, 6 CA) received 2 out of 48 balls tossed and the controls received 10. 88% in the experimental condition reported a negative emotion (e.g. anger). Control subjects reported mainly neutral affect. ANOVA analyses revealed HR variance had an interaction effect (time x condition, p=0.009) and RSA had a main effect (condition, p=0.033). Both experimental groups had increased heart rate variance and increased RSA. Facial coding revealed EA expressed more negative emotion. CA in the experimental condition showed correlation across measures: HR variance, RSA and respiration, suggesting automatic regulation to perceiving loss contained its expression. Most subjects reported feeling sad during the clip. fEMG of the corrugator muscle revealed EA activated higher peak intensity 5.5 seconds earlier than CA (increased 1.571 vs 0.844). EA also had decreased HR and increased RSA, a sign of withdrawal in sadness, earlier. Evidence suggests exposure to loss had stronger effect on EA to increase their arousal and sensitivity thereafter. / M.S. / The study investigated how differences in perceiving a change in social connection might affect emotional responses. There is evidence that Europeans tend to perceive salient objects in the foreground, while East Asians tend to perceive holistically. Due to sensitivity to focal objects, European Americans (EA) were hypothesized to respond negatively with increased heart rate variance on perceiving loss of connection when playing Cyberball, a ball-tossing video game. EA would also feel sadness more intensely, in terms of decreased heart rate and increased vagal activation, at an earlier time during a sad clip. Chinese Americans (CA) were predicted to show no difference in affect from controls. ECG, fEMG, respiration and self-report data were acquired from 51 subjects (38 EA, 13 CA, 25 male, mean age 21.1) in a between-subjects design. 26 subjects (19 EA, 6 CA) received 2 out of 48 balls tossed and the controls received 10. 88% in the experimental condition reported a negative emotion (e.g. anger). Control subjects reported mainly neutral affect. Unexpectedly, both experimental groups had increased heart rate variance. CA in the experimental condition showed correlation across physiological measures: heart rate variance, vagal activation and respiration, suggesting automatic regulation to perceiving loss during Cyberball. These correlations were not observed in the EA, but as predicted, EA in the experimental condition had decreased heart rate and increased vagal activation, a sign of withdrawal in sadness, earlier during a sad clip. Evidence suggests exposure to loss had stronger effect on EA to increase their arousal and sensitivity thereafter.
44

Early Parasympathetic Activity Predicts Later Childhood Social Functioning as Mediated by Emotion Regulation

Fok, Megan January 2021 (has links)
Theories of emotion regulation and social engagement indicate that resting and reactive respiratory sinus arrhythmia (RSA), which reflect vagal activity, in early childhood can inform the development of social and emotional behaviors later in life. Low RSA at baseline and during a stressful task have been associated with symptoms of ED and disorders characterized by social impairments. The current study examined the mediating role of ED at 24-months-old (mo) on the prospective association between early infant resting and reactive RSA at 5 mo on social functioning outcomes at 48 mo, and the mediating role of social functioning at 24 mo on infant RSA at 5 mo and ED at 48 mo in 237 healthy children. It was hypothesized that ED would mediate the relationship between infant RSA and later childhood social function. Results largely indicated no support of the hypotheses and that there is no mediating effect of childhood ED on early RSA on later childhood social behavior; however, there was a significant relationship between infant resting and reactive RSA and later ED. Limitations and future directions for improving the methodology are addressed. / M.S. / Early childhood heart rate has been thought to influence the development of later child emotional and social development. The Polyvagal Theory suggests that low variability in heart rate, as measured by respiratory sinus arrhythmia (RSA), is related to greater difficulties in emotional and social behavior. Finding an underlying biological reason for emotional and social development can be important for understanding childhood psychological disorders. This research study examined healthy children at three different time points during development: 5 months old (mo), 24 mo, 48 mo. RSA was measured at 5 mo, and frustration levels and social abilities at 24 and 48 mo. It was hypothesized that low RSA at 5 mo predicts low social abilities at 48 mo because of high frustration levels at 24 mo. To rule out an alternate hypothesis, this study also tested if low RSA at 5 mo predicts high frustration levels at 48 mo because of low social abilities at 24 mo. The results of this study did not support the predictions and there was no evidence of emotional abilities affecting how RSA predicts later social abilities. Possible explanations for the lack of findings and ideas for future research were discussed.
45

Altered Autonomic Nervous System Function in Chickens Divergently Selected for Body Weight

Kuo, Alice Yi-Wen 01 September 2000 (has links)
Autonomic nervous system activity is related to body weight regulation. Based on the MONA LISA hypothesis it has been suggested that most obese subjects and animals have low sympathetic nervous system activity. The aim of this study was to investigate whether there are differences in autonomic nervous system activity between lines of chickens selected for either high (HWS) or low body weight (LWS). In Exp. 1, various pharmacological agents were injected intravenously, and the changes in blood pressure (BP) and heart rate (HR) of both HWS and LWS chickens were compared. The results showed that the HWS birds had a greater increase in BP and HR than the LWS following injection of atropine, a muscarinic receptor blocker, and LWS birds had a greater decrease in BP and HR to propranolol, a beta- adrenergic receptor blocker than the HWS birds. These results suggested that HWS chickens have higher parasympathetic tone, whereas LWS chickens have a higher sympathetic nervous system tone regulating the cardiovascular system. HWS and LWS chickens displayed a similar response in BP and HR following injection of the ganglion blocker tetraethylammonium chloride. These results suggest that there is no significant difference in the central autonomic nervous system in the cardiovascular regulation between HWS and LWS together. Since there does not appear to be any differences in the activity of the autonomic nervous system activity at the level of the central nervous system, these findings imply that the difference in response to atropine and propranolol could be caused by differences in adrenal activity. The ratio of heart rate and blood pressure after the injection of phenylephrine showed significant difference between these two lines of birds, but not when phenylephrine was injected following atropine. This result indicated that HWS are more dependent on the parasympathetic nervous system to regulate the baroreceptor reflex. The percentage of adrenal and sympathetic impact on the regulation of heart rate showed that LWS females required greater adrenal activity than the other birds. In Exp. 2, the body weight and food intake responses of HWS and LWS chickens to ip injections of reserpine were compared. Reserpine caused a transitory decrease in food intake and body weight in both lines of birds. However HWS chickens recovered more slowly from the depression caused by reserpine than the LWS chickens. This could be due to lower sympathetic nervous system activity. In conclusion, it appears that HWS may have lower sympathetic activity than LWS. Combining the results of both experiments, it appears that the HWS birds have lower sympathetic and higher parasympathetic activity. Furthermore central nervous system autonomic activity in BP and HR regulation is not different between HWS and LWS, but the activity of the adrenal gland may be different between these two lines of birds. / Master of Science
46

Prediction of In-Vivo Antimuscarinic Activity (AMA) by In-Vitro Receptor Binding Assessment and PK/PD Modeling For Prototypical Drugs

Obied, Taghrid Y. 01 January 2007 (has links)
Purpose: To establish a tool, termed as antimuscarinic activity (AMA), to predict the incidence of antimuscarinic adverse events (AMAEs).Methods: A literature review, focused on drugs having off-target interaction with muscarinic receptors, was performed. Prototypical drugs olanzapine, diphenhydramine, paroxetine were selected for the analysis. Scopolamine and darifenacin were included as positive and negative controls, respectively. Physiochemical properties, pharmacokinetic data, and clinical incidence of AMAEs for the selected drugs were collected from reported literature. Extrapolation of literature data was carried-out to obtain exposure data. To determine the drugs muscarinic affinity (Ki values), experiments were performed using 3H-QNB and membrane suspensions of M1, M2, and M3. Cmax, values were combined with Ki values to generate the relevant AMA. Validation of the AMA biomarker was carried-out against the reported AMAEs incidence. Results: With the exclusion of scopolamine and olanzapine for CNS and peripheral AMAEs, respectively, AMA ranking was related to the drugs AMAEs.
47

Variabilidade da frequência cardíaca e qualidade de vida em cães com doença valvar mitral tratados com metoprolol /

Beluque, Tamyris. January 2019 (has links)
Orientador: Marlos Gonçalves Sousa / Resumo: A doença valvar mitral tem alta prevalência em todo o mundo e é a enfermidade cardiovascular mais diagnosticada em cães. A referida enfermidade cardíaca possui caráter progressivo, que frequentemente leva à insuficiência cardíaca congestiva. Por sua vez, a insuficiência cardíaca congestiva é uma síndrome clínica complexa que leva a um baixo débito cardíaco, hipotensão e hipoperfusão tecidual, fazendo com que as demandas de diversos órgãos não sejam devidamente supridas. Com o intuito de ajustar a falha do coração como bomba, o organismo ativa uma série de mecanismos compensatórios que, em curto prazo, normalizam a pressão arterial. Dentre esses mecanismos, se destaca como um dos mais importantes, ativação do sistema nervoso autônomo simpático. Todavia, a ativação desses mecanismos, em logo prazo, resulta em progressão da disfunção ventricular, morte dos cardiomiócitos, desenvolvimento de sinais clínicos e óbito. Quando o débito cardíaco é prejudicado pela falha da função ventricular, a hipotensão relativa estimula os barorreceptores a ativar o sistema nervoso autônomo simpático, conduzindo ao aumento da concentração sérica de noradrenalina na insuficiência cardíaca congestiva. A noradrenalina é uma catecolamina endógena sintetizada pelas células cromafins na medula adrenal, que age em receptoresα1-adrenérgicos, promovendo o aumento da resistência vascular sistêmica, e em receptores β1-adrenérgicos, exercendo atividade inotrópica e cronotrópica positivas. No tratamento da insu... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Mitral valve disease has a high prevalence worldwide and is the most diagnosed cardiovascular disease in dogs. The referred cardiac disease presents a progressive character, which often leads to congestive heart failure. In turn, congestive heart failure is a complex clinical syndrome that leads to low cardiac output, hypotension and tissue hypoperfusion, causing the demands of various organs not to be adequately met. In order to adjust heart failure as a pump, the body activates a series of compensatory mechanisms that, in the short term, normalize blood pressure. Among these mechanisms, it stands out as one of the most important, sympathetic autonomic nervous system activation. However, the activation of these mechanisms, in the long term, results in progression of ventricular dysfunction, death of cardiomyocytes, development of clinical signs and death. The main mechanism is the activation of sympathetic autonomic nervous system. When cardiac output is impaired by failure of ventricular function, relative hypotension stimulates baroreceptors to activate the sympathetic autonomic nervous system, leading to increased serum noradrenaline concentration in congestive heart failure. Noradrenaline is an endogenous catecholamine synthesized by chromaffin cells in the adrenal medulla, which acts at α1 -adrenergic receptors, promoting the increase of systemic vascular resistance, and at β1 -adrenergic receptors, exerting positive inotropic and chronotropic activity. In the treatment... (Complete abstract click electronic access below) / Mestre
48

Análise espectral de sinais atriais e sua correlação topográfica com a inervação parassimpática cardíaca / Spectral analysis of atrial signals and its topographic correlation with cardiac parassimpathetic innervation

Rivarola, Esteban Wisnivesky Rocca 22 August 2011 (has links)
Objetivo. Verificar se as características espectrais dos eletrogramas atriais (EgA) em ritmo sinusal (RS) se correlacionam com a presença de gânglios parassimpáticos cardíacos. Materiais e Resultados. Treze pacientes encaminhados para submeter-se a ablação de fibrilação atrial (FA) foram incluídos de forma prospectiva. Previamente ao início da ablação, realizou-se o registro de EgA em RS em uma série de regiões anatômicas pré-determinadas, seguindo-se uma ordem sequencial. Em seguida, aplicou-se estímulos elétricos de alta frequência (20 Hz de frequência, amplitude de 100 V e duração de pulso de 4 ms), nos mesmos locais. Uma resposta vagal evocada foi definida como um súbito aumento no intervalo RR ou a indução de bloqueio na condução átrio-ventricular imediatamente após a aplicação do estímulo de alta-frequência (EAF). Procedeu-se à análise espectral dos sinais atriais em RS registrados, com amostragem de 1000 Hz, janela Hanning. No total, 1488 EgA oriundos de 186 locais anatômicos foram registrados, sendo 129 de regiões com resposta vagal negativa e 57 correspondentes a regiões de resposta vagal positiva. A duração do eletrograma e o número de deflecções foram similares nos pontos com resposta vagal positiva e negativa. A densidade de potência espectral em locais de resposta vagal positiva, no entanto, foi menor entre 26 e 83 Hz, e maior entre 107 e 200 Hz, comparados com os locais de resposta negativa. A área sobre a curva entre 120 e 170 Hz normalizada para a área total do espectro foi testada como um novo parâmetro diagnóstico. A análise de curva ROC demonstrou que o valor area 120-170 / area total > 0,14 foi capaz de identificar locais de inervação vagal com sensibilidade de 70,9% e especificidade de 72,1%. Conclusão. A análise espectral de sinais atriais durante RS é um método factível e simples de mapear os locais de inervação parassimpática cardíaca, sem a necessidade de qualquer tipo de estimulação / Objective. To verify whether spectral components of atrial electrograms (AE) during sinus rhythm (SR) correlate with cardiac ganglionated plexus (GP) sites. Methods and Results. Thirteen patients undergoing atrial fibrillation (AF) ablation were prospectively enrolled. Prior to radio frequency application, endocardial AE were recorded with a sequential point-by-point approach. Electrical stimuli were delivered at 20 Hz, amplitude 100 V, and pulse width of 4 msec. A vagal response was defined as a high-frequency stimulation (HFS) evoked AV block or a prolongation of RR interval. Spectral analysis was performed on single AE during SR, sampling rate of 1000 Hz, Hanning window. Overall, 1488 SR electrograms were analyzed from 186 different left atrium sites, 129 of them corresponding to negative vagal response sites and 57 to positive response sites. The electrogram duration and the number of deflections were similar in positive and negative response sites. Spectral power density of sites with vagal response was lower between 26 and 83 Hz and higher between 107 and 200 Hz compared with negative response sites. The area between 120 and 170 Hz normalized to the total spectrum area was tested as a diagnostic parameter. ROC curve analysis demonstrated that an area 120-170 / area total value > 0,14 identified vagal sites with 70,9% sensitivity and 72,1% specificity. Conclusions. Spectral analysis of AE during SR is feasible and simple method of mapping the cardiac autonomic nervous system (ANS), with no stimulation required
49

Participação do sistema nervoso parassimpático no metabolismo energético e na proliferação celular em ilhotas pancreáticas de ratos obesos-MSG

Lubaczeuski, Camila 01 August 2013 (has links)
Made available in DSpace on 2017-07-10T14:17:01Z (GMT). No. of bitstreams: 1 Camila.pdf: 1579699 bytes, checksum: 81aed6e2676f0085056d80a67c1ae83e (MD5) Previous issue date: 2013-08-01 / The growing number of overweight and obesity has led to an increase in the number of patients with insulin resistance and diabetes mellitus type 2. MSG obese rats were glucose intolerant, insulin resistant and theirs pancreatic islets secrete more insulin in response to glucose. Subdiafragmatic vagotomy changes the response of islets to glucose and improves glucose homeostasis, supporting the hypothesis that an unbalance of autonomic nervous system with increased parasympathetic nervous system (PNS) action but a decreased sympathetic nervous system function. Studies showed that the PNS is also involved in β-cell proliferation. Therefore, we investigated of PNS participation, using a subdiafragmatic vagal denervation, upon pancreatic β-cell function and mass regulation, and the body glucose control disruption in MSG-obese rats. For this, Male Wistar rats received during the first five days of life monosodium glutamate (MSG) or saline. Subdiaphragmatic vagotomy was performed at 30 days of life. At 90 days of age, we verified static insulin secretion, pancreas morphometric, ERK expression in islets, glucose homeostasis and lipidis. The MSG treatment caused obesity at 90 days of life. MSG rats presented lower body weight and nasoanal length, increased Lee index and fat depots, normoglycemia, hyperinsulinemia, dyslipidemia, glucose intolerance and insulin resistance when compared to CTL. Vagotomy performed at 30-days of age prevented obesity, fat deposition in the liver and ameliorated glucose tolerance and insulin sensitivity in adult MVAG rats in relation to MSG rats. Islets from MSG rats secreted more insulin at stimulatory glucose concentrations than CTL islets. Histological analysis showed that pancreatic islets from MSG rats were lower with a reduction in β-cell area without modification in α-cell content when compared with CTL. Also, MSG group presented an increased number of pancreatic islets per mm2, with higher number of islets, which may contributes to the higher islet and β-cell relative mass in the MSG pancreas. These effects were associated with enhanced proliferation in MSG group. The number of MVAG pancreatic islet were less than MSG. Vagotomoy performed at 30-days of age, reduced islet and β-cell area in the pancreas from 90-days old CVAG rats. Finally, the relative islet and β-cell mass in MVAG and CVAG rats was similar to CTL. Here we verified if ERK was involved in β-cell replication in MSG rats, but presented no alteration. We demonstrate for the first time that adult MSG rats showed enhanced pancreatic β-cell proliferation which contributes to the higher islet insulin secretion in response to glucose. The vagus nerve is the main factor involved in such a process, since vagotomy performed at 30 days of age prevented islet morphological alterations in adult MVAG rats. Possibly this increase PNS activity in MSG endocrine pancreas is responsible to hyperinsulinemia that enhanced fat storage, damaged glucose homeostasis and insulin action in MSG obesity. / O crescente número de pessoas com sobrepeso e obesidade tem levado ao aumento no número de pacientes com resistência à insulina (RI) e portadores do Diabetes mellitus tipo 2. Ratos obesos MSG são intolerantes à glicose (Gli), RI e suas ilhotas pancreáticas secretam mais insulina em resposta à concentrações de Gli. A vagotomia subdiafragamática altera a responsividade das ilhotas à Gli e melhora a homeostase glicêmica nestes animais, sugerindo um desbalanço do sistema nervoso autonômico, com aumento do tônus parassimpático e redução do simpático. Estudos demonstram que o sistema nervoso parassimpático (SNP) possui efeito na proliferação das células β-pancreáticas. Desta forma, investigamos a participação do SNP, através da vagotomia subdiafragmática, no metabolismo energético e na proliferação das ilhotas e de células β-pancreáticas de ratos obesos-MSG. Para isto, ratos Wistar machos receberem durante os cinco primeiros dias de vida glutamato monossódico (grupo MSG) ou salina (grupo CTL). A vagotomia subdiafragmática foi realizada aos 30 dias de vida formando os grupos MVAG e CVAG. Aos 90 dias, verificamos a secreção estática de insulina, homeostase glicêmica e lipídica, morfometria do pâncreas e conteúdo proteico da ERK nas ilhotas. Ratos MSG apresentaram redução do peso corporal e comprimento nasoanal, aumento do índice de Lee e acúmulo de gordura, normoglicêmia, hiperinsulinemia, dislipidemia, intolerância à Gli e RI comparados aos CTL. A vagotomia realizada aos 30 dias de vida preveniu obesidade, acúmulo de gordura no fígado e melhorou a tolerância à Gli e a sensibilidade à insulina em ratos MVAG adultos em relação aos ratos MSG. As ilhotas dos animais MSG secretaram mais insulina quando estimulada pela Gli, em relação aos animais CTL. As análises histológicas mostram que as ilhotas pancreáticas dos animais MSG são menores com redução da área das células β sem alteração nas células α em relação aos CTL. O grupo MSG apresenta um aumento do número das ilhotas por mm2, que pode estar contribuindo com o aumento da massa relativa das ilhotas e das células β. Esse efeito está associado ao aumento da proliferação no grupo MSG. O número de ilhotas foi menor nos MVAG em relação aos MSG. A vagotomia realizada aos 30 dias de vida reduziu a área das ilhotas e das células β aos 90 dias de vida nos animais CVAG. Finalmente, a massa relativa das ilhotas e da células β no MVAG e CVAG foram similares ao CTL. Verificamos se a ERK estava envolvida na proliferação das células β nos ratos MSG, porém não apresentaram alterações desta proteína. Pela primeira vez demonstramos que ratos MSG apresentam aumento da proliferação das células β que contribui com o aumento da secreção de insulina em resposta à Gli. O nervo vago é o principal fator envolvido neste processo, visto que a vagotomia realizada aos 30 dias de vida preveniu as alterações morfológicas das ilhotas nos ratos MVAG adultos.
50

Modeling the Parasympathetic Nervous Response to an Emotional Task: The Interaction of Heart Rate Variability, Personality and Emotion Regulation

Root, Lindsey Marie 17 July 2009 (has links)
Heart rate variability (HRV), a physiological marker of autonomic nervous system (ANS) engagement, has been associated with a wide variety of clinical and psychological processes. High frequency (HF) HRV power, specifically, has been linked with the parasympathetic nervous system (PNS) and self-regulation. The current inquiry used a random effects growth model to study the HF HRV response to an emotional task and to predict individual differences in HF HRV as a function of trait hostility, neuroticism, and emotion regulation strategies (e.g., positive reappraisal, positive refocusing). Results indicated that the task engaged both branches of the ANS. HF HRV was not related to either hostility or neuroticism. However, positive reappraisal was associated with both high baseline values of HF HRV (i.e., greater initial parasympathetic activation) and lower rates of reactivity (i.e., less parasympathetic withdrawal). Overall, these results add to the evidence that positive reappraisal is a powerful component of emotion regulation and may be an important intervention target.

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