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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.
31

Stress Reactivity as a Predictor of Emotional Eating

January 2016 (has links)
abstract: Childhood obesity is associated with many well established health risks as well as high annual public health costs. Because of this, the childhood obesity literature has highlighted the need to detect at-risk groups in order to implement targeted preventions. Emotional eating has been identified as an unhealthy behavior and a risk factor for overweight status among children though very little is known about what predisposes children to emotionally eat. Stress has often been found to elicit emotional eating but most studies looking at this relationship have relied on self-reports in adult and clinical samples. Thus, the current study seeks to investigate the relationship between stress reactivity (measured using heart rate variability) and emotional eating in a sample of 247 children between the ages of 4-6. Furthermore, levels of control may moderate the relationship between stress reactivity (HRV) and emotional eating. Linear regression analysis was used to explore these relationships. It was expected that higher levels of reactivity to stress would predict an increased likelihood of emotional eating. This association was expected to be attenuated among children with higher levels of inhibitory control and attentional focusing as well as lower levels of impulsivity. However, the hypothesized findings were not supported by the data. Despite these null findings, and in light of several limitations, it is still hypothesized that emotional eating involves physiological and impulsivity/effortful control processes. Implications of future research are discussed. / Dissertation/Thesis / Masters Thesis Psychology 2016
32

Změny elektrického pole srdce u poruch glukózového metabolismmu a možnosti jejich ovlivnění úpravou narušené autonomní nervové regulace / Changes of the electric field of the heart in disorders of glucose metabolism and ways of influencing them by correction of impaired autonomic nervous regulation

Fialová, Elena January 2017 (has links)
Diabetes mellitus (DM) is not just a simple metabolic disorder, however, it is considered to be a cardiovascular disease of a metabolic origin. This is apparent especially when speaking about type 2 diabetes (DM II). Patients with DM have a high occurrence of vegetative nervous system (VNS) disorders that manifest themselves as an increased activity of the sympathetic nervous system that correlates with peripheral autonomic neuropathy and is considered to be the major pathophysiological mechanism for the development of DM II. The objective of our study was to determine whether a comprehensive spa treatment (ST) may affect the level of the sympathetic tone of patients suffering from DM II. As an indicator of the sympathetic tone, selected electrocardiographic parameters derived from the HRV, microvolt T-wave alternans, and microvolt R-wave alternans were evaluated. The electrophysiological examination of patients was performed before and after a three-week spa treatment using the KARDiVAR system. The method is used to examine the current state of the autonomic nervous system and carry out an analysis of risk factors and adaptive capabilities of the organism. The results showed favorable changes in DM II patients after the ST, primarily in terms of reduced sympathetic adrenal system activity,...
33

Cardiovascular autonomic dysfunction in Parkinsonian syndromes

Kallio, M. (Mika) 24 July 2001 (has links)
Abstract Autonomic nervous system (ANS) disturbances are common in Parkinson's disease (PD), but also in other Parkinsonian syndromes, especially in multiple system atrophy (MSA). The differentiation between various Parkinsonian syndromes may be difficult, but it is important for prognostic and therapeutic purposes. The aim of this study was to determine the ability of different analysis methods to reveal cardiovascular regulation disturbances in PD and to evaluate the diagnostic capacity of autonomic tests to differentiate between various Parkinsonian syndromes. Furthermore, this study aimed to evaluate the relationships between ANS disturbances and the clinical characteristics of PD. In addition, the cardiac autonomic function was evaluated during various sleep stages for the first time in untreated PD patients by using spectral heart rate variability (HRV) measures to determine possible sleep stage specific cardiovascular regulation disturbances. Cardiovascular autonomic reflexes were evaluated in 62 untreated and newly diagnosed PD patients, 34 PD patients under antiparkinsonian medication, 47 MSA patients and 15 patients with progressive supranuclear palsy (PSP). The usefulness of different analysis methods was evaluated in a subgroup of 32 untreated PD patients. A further 21 untreated PD patients underwent one-night polysomnography for nocturnal heart rate variability analysis. PD patients with hypokinesia/rigidity as their initial onset sign had a significantly lower max-min ratio in the deep breathing test than those patients with tremor as the initial sign. MSA patients showed significant reductions in both HRV and blood pressure responses during orthostatic provocation, whereas PSP patients had normal results. Absolute spectral measures yielded the clearest indicators separating the PD patients from the controls, while the cardiovascular reflexes proved more useful than the normalised spectral HRV measures in revealing the differences between the two groups. HRV was abnormally decreased during non-REM sleep in PD patients but not during REM sleep or the S1 sleep stage. The normalized high frequency power was significantly decreased in PD patients during sleep stages S2-4, while the standard deviation of the R-R intervals was increased during the same sleep stages, possibly corresponding to the increased motility of PD patients during these sleep stages. The clinical characteristics of PD deserve particular attention in connection with ANS disturbances, since autonomic failure seems to be more pronounced in PD patients with hypokinesia/rigidity as their initial sign. The evaluation of the autonomic function may also be helpful in the differential diagnosis of Parkinsonian syndromes. Spectral analysis methods should be implemented in the evaluation of ANS dysfunction to achieve the best possible efficacy in the differentiation of pathological responses from normal ones. Nocturnal analysis of cardiovascular regulation revealed new and interesting features of pathologic HRV in PD patients, thus when HRV is evaluated, the different sleep stages should be analysed separately.
34

Development of methodology for assessing counseling interactions:developing the Counselor Response Observation System and assessing applicability of heart rate variability to the measurement of client emotions during verbal reporting

Rantanen, A. (Antti) 03 December 2014 (has links)
Abstract The general purpose of this study was to develop methodology for assessing counseling interactions. The first main objective of the research was to develop measures for assessing counselors’ responses and client-centeredness (Study I). Specific aims connected to the first objective were to assess the content validity and inter-rater reliability of the Counselor Response Coding System (CRCS) and the content validity, construct validity and inter-rater agreement of the Skilled Verbal Responding Scale (SVRS), which are measures included in the Counselor Response Observation System (CROS). The second main objective was to assess the applicability of heart-rate variability (HRV) to the measurement of emotions during clients’ verbal reports of unpleasant experiences (Studies II and III). The setting was analog with client-centered counseling aims in that the subjects produced verbal reports of their unpleasant experiences. Specific aims connected to the second objective were to examine the differences in subjects’ emotions between viewing and reporting unpleasant experiences and to examine the differences in their emotions between reporting pleasant and unpleasant experiences by measuring HRV. The results supported the content validity and inter-rater agreement of the CRCS and the content validity, construct validity, and inter-rater reliability of the SVRS. Overall, the results from the CROS testing can be considered a good starting point toward its further validation. The results from the HRV experiments were consistent with earlier findings and indicated that the subjects’ sympathetic activity was lower and that their parasympathetic activity higher when they reported unpleasant pictures than it was when they viewed them. This dynamic was not observed with the pleasant pictures. The results suggest that HRV and emotions during reporting should be interpreted in relation to the initial experiences and emotions in the viewing phase. / Tiivistelmä Tutkimuksen yleinen tavoite oli ohjausvuorovaikutuksen arviointimenetelmien kehittäminen. Tutkimuksen ensimmäinen päämäärä oli kehittää ohjaajan responsseja ja ohjaustoiminnan asiakaskeskeisyyttä arvioivia mittareita (Osajulkaisu I). Tarkempina ensimmäiseen päämäärän kytkeytyvinä tavoitteina oli arvioida Ohjausresponssien mittausjärjestelmään (CROS) sisältyvien Ohjausresponssien koodaussysteemin (CRCS) sisällön validiteettia ja interarvioitsijareliabiliteettia sekä Taitavan verbaalisen toiminnan skaalan (SVRS) sisällön validiteettia, rakennevaliditeettia ja interarvioitsijareliabiliteettia. Toisena päämääränä oli arvioida sykevariaatiomittauksen (HRV) soveltuvuutta asiakkaan emootioiden arviointiin puheen aikana (Osajulkaisut II ja III). Asetelma tässä oli analoginen asiakaskeskeisen ohjauksen tavoitteiden kanssa ja HRV -kokeissa koehenkilöt tuottivat verbaalisia kuvauksia emotionaalisesta kokemuksesta. Toiseen päämäärään kytkeytyvät tarkemmat tavoitteet olivat tarkastella eroja koehenkilöiden emotionaalisessa aktiviteetissa epämiellyttävien kuvastimulien katselun ja raportoinnin välillä sekä eroja miellyttävien ja epämiellyttävien kuvastimulien raportoinnin välillä HRV mittauksen avulla. Tulokset tukivat CRCS:n sisällön validiteettia ja interarvioitsija -reliabiliteettia sekä SVRS:n sisällön validiteettia, rakennevaliditeettia sekä interarvioitsija -reliabiliteettia. Kokonaisuudessaan CROS -arvioinnin tulokset ovat hyvä lähtökohta sen kehitystyössä. HRV -kokeiden tulokset olivat yhdenmukaisia aiempien löydösten kanssa ja indikoivat, että koehenkilöiden sympaattinen aktiviteetti oli matalampaa ja parasympaattinen korkeampaa, kun he raportoivat epämiellyttäviä stimuleita verrattuna stimulien katseluun. Tätä dynamiikka ei havaittu miellyttävien stimuleiden kohdalla. HRV -kokeiden tulokset indikoivat, että HRV ja emootiot tulisi tulkita suhteessa alkuperäiseen kokemuksen valenssiin, mikä on raportoinnin kohteena.
35

Measurement of cardiac vagal outflow by beat-to-beat R-R interval dynamics

Kiviniemi, A. (Antti) 12 September 2006 (has links)
Abstract Analysis of beat-to-beat heart rate variability (HRV) provides information of cardiac vagal outflow to the sinus node. Some methodological problems might, however, be involved in the analysis of cardiac vagal outflow from ambulatory Holter recordings, such as saturation, physical activity, and abrubt prolongations of R-R intervals unrelated to respiration. The purpose of this thesis was to assess the physiological basis of beat-to-beat HRV and to develop and assess new methods for the quantification of cardiac autonomic modulation from ambulatory Holter recordings. The study population consisted of 89 healthy volunteers (age 24 ± 4 years) and 590 patients with a recent acute myocardial infarction (AMI, age 61 ± 10 years). The relationship between R-R interval length and the high-frequency (HF) spectral power of the R-R intervals was assessed in 76 healthy subjects and 82 post-AMI patients. The effects of aerobic exercise training on the dynamics between R-R interval and HF power were evaluated by means of a controlled 8-week training intervention (n = 17). The effects of sympathetic activation and concomitant sympathetic and vagal outflow on beat-to-beat HR dynamics were studied in laboratory conditions (n = 13). A new method for quantifying beat-to-beat HRV from the R-R interval lengths where the relationship between HF power and R-R interval is most linear was developed to avoid the confounding effects of possible saturation, physical activity, and random R-R interval dynamics. The clinical significance of the new method was assessed in a series of 590 post-AMI patients. Saturated HF R-R interval dynamics, expressed as a lack of increase in HF power despite an increased R-R interval, was observed in 35 healthy subjects and 9 post-AMI patients. In the training study, 7 subjects out of a total of 17 had saturated HF power before the intervention. After the training period, 5 new cases of saturated HF power were observed. In laboratory conditions, co-activation of sympathetic and vagal outflow resulted in random R-R interval dynamics. In post-AMI patients, HF power analyzed exclusively from the R-R intervals where the relationship between the R-R interval and HF power was most linear (Vindex) predicted independently the occurrence of SCD among post-AMI patients, while traditionally analyzed HF power did not. In conclusion, the saturation of beat-to-beat HRV in ambulatory conditions is a common phenomenon. The prevalence of saturated HF power increases due to enhanced cardiac vagal outflow induced by aerobic training. Finally, the novel analysis of vagally mediated HRV (Vindex) provides unique information that cannot be obtained by traditional analysis of HF R-R interval dynamics.
36

Markers of microvascular complications in adolescents with type 1 diabetes

Tossavainen née Riihimaa, P. (Päivi) 10 January 2003 (has links)
Abstract The markers of microvascular complications of type 1 diabetes were evaluated in adolescents in a cross sectional survey of 100 out of 138 eligible patients aged 9-19 years with a duration of diabetes over two years who visited the Paediatric Outpatient Clinic at Oulu University Hospital in 1997-1999, and one hundred healthy controls. Two patients in early or mid-puberty had non-proliferative diabetic retinopathy, but no other signs of microvascular complications. The five patients with persistent microalbuminuria were all girls; one prepubertal, one late pubertal and three postpubertal. Their mean glycated haemoglobin A1c (HbA1c) was higher, but they had a similar duration of diabetes and age distribution to those without microalbuminuria. The adolescent patients were predisposed to higher fasting serum total and low-density lipoprotein cholesterol and triglyceride levels and higher diastolic blood pressure than the control subjects. The proportional total body fat was highest in the girls with diabetes by the end of puberty, while serum leptin levels did not differ between the patients and healthy controls. The patients had low fasting serum insulin levels and high insulin-like growth factor-binding protein 1 levels, related to hypoinsulinaemia. Distal motor nerve function in the lower extremities were already affected before puberty, and distal and proximal nerve function deteriorated as puberty advanced. Ten patients had neurophysiologically confirmed distal diabetic polyneuropathy, and they were older and they had longer duration of diabetes and higher HbA1c than patients without polyneuropathy. Although cardiovascular function was in the main well preserved in the adolescents with type 1 diabetes, the power spectrum analysis of heart rate variability showed attenuated autonomic nervous system reactivity. Taken together these data show that a relatively small proportion of adolescents with type 1 diabetes have signs of microvascular complications. The prevalences of diabetic retinopathy, persistent microalbuminuria and distal diabetic polyneuropathy were 2%, 6% and 10%, respectively. Pubertal maturation seems to promote the progression of early signs of microvascular complications in patients affected by type 1 diabetes.
37

Changes in heart rate variability in varsity athletes from baseline to post-injury and return to play

Rodway, Allison 03 January 2018 (has links)
Objective: To determine the change in HRV in concussed varsity athletes from baseline to post-injury to return to play. Design: Quasi-experimental, repeated measures design. Participants: five male varsity athletes four rugby, one basketball (mean age 19.6 ± 1.52 years), number of previous concussion 1.6 ± 0.55. Measurements: HR & HRV frequency domain (LF n.u., HF n.u., LF/HF ratio, Total Power) & Heart rate (bpm) during both seated rest and steady state exercise using a stationary cycle. Results: Repeated measures ANOVA revealed a significant difference between baseline (pre- injury) resting heart rate and first post-injury assessment resting heart rate (p=0.037). Resting Total Power was significantly different between baseline (pre-injury) and first post-injury assessment (p=0.044) and between first post-injury and second post-injury assessment (p=0.010). No statistical significant differences in any variables were found during exercise, however the trends in the changes of HRV were similar to other research studies and could be of clinical importance. Conclusion: Athletes display dysfunction in neuroautonomic cardiovascular regulation post-concussion as seen with changes in HRV. Findings of this study warrant further investigation into the use of HRV as a marker of concussion and concussion recovery. / Graduate
38

Hyperacusis, Autonomous Regulation and Executive Functioning : Effects of noise exposure over time / Hyperakusi, Autonom Reglering och Exekutiva Funktioner : Effekter av brus-exponering över tid

Nilsson, Oskar January 2016 (has links)
Hyperacusis is a condition in which sufferers experience everyday sounds in their surroundings as unmanageable and disturbing. The condition is often associated with symptoms such fatigue, headaches, sleep disturbances and difficulties concentrating. Present study aimed to investigate how people are affected when exposed to noise over time. This was operationalized by collecting data from essentially three domains; subjective, physiological and cognitive. Since hyperacusis is largely defined by the individuals’ subjective experience, participants were divided into three groups based on their own subjective reports of discomfort during an exposure to white noise (60db). Cognitive performance was assessed using two well established measurements in the beginning and the end of the exposure session. Contrary to expectations, the groups did not differ significantly in cognitive performance. Heart rate variability was measured during the exposure session and was hypothesized to be lower in participants experiencing higher discomfort. As expected, the groups differed in their expressed variability in the direction of the hypothesis.
39

Heart rate variability used to assess changing autonomic functionin transmissible spongiform encephalopathies

Glover, David January 2011 (has links)
The dorsal vagal nucleus (DMNX) and nucleus ambiguus (NA) are two anatomically distinct regions of the medulla oblongata of the brainstem involved with the control of the heart on a beat to beat basis. The vagus nerve has parasympathetic cell bodies located in the DMNX and NA. The presence of the disease associated prion (PrPD) in the DMNX and NA is used in the post mortem diagnosis of transmissible spongiform encephalopathies (TSEs) in animals. It has been shown that PrPD alters the neuronal discharge properties of infected tissue (Barrow, Holmgren et al.1999; Collinge, Whittington et al. 1994). I wished to investigate whether a change in heart rate variability (HRV) influenced by the presence of PrPD deposits in brainstem areas of animals and people incubating TSEs would be detectable. Recordings from control and infected sheep, cattle and humans, consisting of three hundred-second samples of electrocardiogram (ECG) were collected from species specific healthy controls and subjects incubating TSE disease. Data were digitised at a sampling frequency of 1kHz and were translated and analysed using standard software (CED Spike2 ; IBM SPSS). Artefacts and missed beats were corrected based upon screening by eye. ECG R-wave timings were obtained in order to determine variability in the R-R intervals. An instantaneous tachogram was constructed from which power spectra were calculated. Power spectral analysis along with simpler time domain estimates of HRV, such as RMSSD, were employed to investigate differences between control and infected animals. In addition R wave variability within each breath was utilized to examine the vagal control of the heart in relation to breathing and thus investigate a change in function of the specific neurological areas of the brainstem used as diagnostic criteria for such diseases. It was found there were significant differences (p<0.05) in the HRV of infected sheep, cattle and humans incubating TSE disease compared to control samples. Repeated non-invasive longitudinal tests may provide a means to screen animals and humans for the presence of disease associated prions and may give applications in the objective assessments of putative therapeutics in addition to identifying TSE disease at a preclinical stage.
40

Analýza variability srdečního rytmu pomocí entropie / Entropy for heart rate variability analysis

Zemánek, Ladislav January 2013 (has links)
The analysis of HRV is an advanced and noninvasive method which is used to investigate the involuntary nervous system. It is also one of the important parameters of its proper function. Heart rate variability can also be analyzed by entropy, which studies the discrepancy of the RR intervals of the HRV signal and thus can be used to diagnose cardiac diseases

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