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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.
151

Neurophysiological findings in Guillain-Barré syndrome at different stages, a retrospective study

Norling, Maja January 2021 (has links)
Introduction: Guillain-Barré syndrome (GBS) is a neurological disease caused by an autoimmune attack on the peripheral nerves. The main symptoms are loss of motor and sensory skills in the upper and lower extremities. Autonomic dysfunction also occurs.Aim: To identify which parameters in neurography examination that are showing pathology at three different stages from the onset of symptoms. To practically perform and evaluate different electrode placements at RR-intervals.Materials and methods: The first part of this study was a retrospective study with results from 58 patients which were diagnosed with GBS in 2010-2020 at the University Hospital in Uppsala. The second part of this study included measurement of the heart rate variation with RR-intervals at different electrode placement in ten healthy volunteers. Results: In part 1 of the project, there were no significant differences between the groups at distal latency in the ulnar nerve, F-latency in the tibial nerve and in the conduction velocity in the sural nerve. However, there were significant differences in the amplitude of the radial nerve. In part 2 of the project, there were significant differences between the electrode placements, and most artifacts were found with electrodes placed on the shoulders.Conclusion: Examination with neurography and RR-intervals plays an important role in the diagnosis of GBS. As the amplitude in the radial nerve was the only one that showed significant differences between the groups, the nerve is recommended to be examined bilaterally. With a high presence of artifacts in RR-intervals with electrodes placed on the shoulders and wrists, placement on the chest is to be recommended.
152

The Relationship Between Traumatic Brain Injury and Disruptions in Heart Rate Variability and Heart Rate Variability Biofeedback: A Systematic Review

Talbert, Leah D. 08 April 2022 (has links)
Background: Traumatic brain injury is a significant public health problem. Heart rate variability is a potential modality to measure physiological dysfunction following traumatic brain injury to assist in determining recovery time and the relationship between traumatic brain injury severity and recovery. To date, a summary of the evidence across injury severities and the possible role of heart rate variability biofeedback in traumatic brain injury treatment is lacking but needed to determine potential clinical utility. Participants and Methods: We followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Systematic literature searches on CINAHL, Embase, PsycINFO, SPORTDiscus, and MEDLINE were conducted in August of 2020. There were two parts to this systematic review. Part I reviewed the relationship between heart rate variability and injury severity, recovery, and cognitive and emotional functioning. Part II reviewed the relationship between heart rate variability biofeedback and traumatic brain injury. Two coders coded each article and provided quality ratings with discrepancies resolved by consensus. Results: Regarding Part I, eighty-five papers met inclusion criteria. For outcome measures, eight studies (9%) focused on HRV as a predictor of mortality following moderate-to-severe traumatic brain injury; 9 studies (10%) included a measure of post-concussive symptom improvement; 7 studies (8%) included a measure of mood disturbance/change; 3 studies (3%) assessed return to consciousness. Overall, there appears to be a positive relationship between increased heart rate variability and recovery of clinical symptoms following traumatic brain injury. For Part II, seven papers met inclusion criteria. All studies included a measure of mood; 5 studies (71%) included neuropsychological functioning as an outcome measure; 1 study (14%) included a measure of life satisfaction. On average, participants completed 14 sessions of heart rate variability biofeedback (mean = 13.5, SD = 13.5, range = 1 to 40). Biofeedback was associated with improved heart rate variability following traumatic brain injury, though the methodological quality is questionable, and more controlled studies and randomized controlled trials are needed. Conclusions: Findings to date suggest a positive relationship between increased heart rate variability and recovery of clinical symptoms, including improvements in cognitive function and physical symptoms including headaches, dizziness, and sleep problems. Literature on traumatic brain injury and heart rate variability biofeedback treatment is in the early stages, and effectiveness is unclear due to poor-to-fair study quality, though early results are promising.
153

Development and Evaluation of Virtual Reality Heart Rate Variability Biofeedback Application / Utveckling och utvärdering av en Virtual Reality lösning för Biofeedback av hjärtfrekvensvariabilitet

Tang, Zihao January 2018 (has links)
Background: Reduced heart rate variability is an important factor in evaluation of autonomic nervous system and diseases. Resonance frequency breathing is a non-invasive and effective training method for increasing heart rate variability. Turing this breathing exercise into a video game is an efficient way to reduce training time and vapidity. Though there has been a successful implementation in 3D game, the influence of virtue reality technology application and interaction elements still need to be explored. Objective: The main objective is to build and evaluate the virtue reality game. Applying appropriate game design and interaction elements will also be discussed. The correct and efficient training should be ensured. Also, recognizing the relationship between game elements and efficiency is also included in the task. By evaluating the impact in heart rate variability biofeedback, the understanding of breathing training game design will be broadened and deepened. Methods: A 3D virtue reality running game is designed with biofeedback framework. Development process is conducted in a user-centred way with interface test. The summative evaluation will be performed 10 participants in a controlled setting. (participant age and health state) Each participant will fill a post-test questionnaire about game experience. The sensor data will be stored on local device. Qualitative analyse of data will be done. Results: VR environment game has shown more significant effects in helping increase heart rate variability than normal game (P<0.05). Both modes have shown more than 50% increase in standard deviation of heart rate variability. A high immersion and positive effects along was reported by a Game Experience Questionnaire. Conclusion: The results have shown that the VR game has the potential to help increase HRV via the resonance breathing training. The game can also allow long-term study by increasing the motivation of participants. Evaluation with GEQ are presented, which will give insights about the usability of this game. Additionally, the new tracks for future study have been explored.
154

Overexpression of human Cu/Zn Superoxide Dismutase in Mice; The Effect of Increase Superoxide Scavenging on Autonomic Control of the Heart.

Hatcher, Jeffrey 01 January 2015 (has links)
Dysregulation of the autonomic cardiovascular control is a complication of diseases including diabetes, hypertension, sleep apnea, and aging. A common factor in these conditions is an increase in reactive oxygen species (ROS) in neural, cardiac, and endothelial tissues. Cu/Zn superoxide dismutase (SOD1) is an intracellular anti-oxidant enzyme that catalyzes dismutation of the superoxide anion (O2.-) to hydrogen peroxide (H2O2). Expression and function of this enzyme are diminished in pathologies that impair cardiovascular autonomic control. This study employed mice overexpressing a transgene for human SOD1 (hSOD1) to determine if its overexpression would alter autonomic regulation of BP, HR, and BRS in healthy animals, and if this animal line (C57B6SJL-Tg (SOD1)2 Gur/J) could be used in future studies to determine if hSOD1 overexpression can preserve cardiac autonomic function in disease models. To accomplish this aim, using anesthetized SOD1 and C57 (control) mice, we recorded HR, and aortic depressor nerve (ADN) activity changes in response to pharmacologically-induced BP changes in order to measure baroreflex and baroreceptor sensitivity, respectively. In order to identify any alterations in central, efferent, and cardiac components of the baroreflex arc, we electrically stimulated the left ADN and left cervical vagus and compared the reductions in BP and HR between the C57 and SOD1 mice. Time- and frequency-domain analysis of heart rate variability (HRV) was performed using pulse pressure recordings prior to pharmacologic or surgical procedures. We found that hSOD1 overexpression in the SOD1 mouse line, in comparison to C57 controls did not significantly affect resting HR (C57: 558 ± 8 vs. SOD1:553 ± 13 beats-per-minute) or blood pressure (C57: 88.8 ± 2.9 vs.SOD1: 85.8 ± 2.1 mmHg). hSOD1 overexpression did not affect the decrease in average mean arterial pressure (MAP) following injection of sodium nitroprusside (SNP) (C57: 38.7 ± 1.4 vs. SOD1: 39.5 ± 1.3 mmHg) or increase in average MAP (C57: 135.8 ± 3.1 vs. SOD1: 136.6 ± 3.5 mmHg) following injection of phenylephrine (PE). BRS, as measured by the averaged regression lines for ΔHR/ΔMAP for the SNP-induced tachycardic baroreflex (C57: 0.57 ± 0.06 bpm/mmHg, SOD1: 0.61 ± 0.08 bpm/mmHg)) and the PE-induced bradycardic baroreflex (C57: -2.9 ± 0.57 bmp/mmHg, SOD1: -4.3 ± 0.84 bpm/mmHg) are not significantly different between C57 and SOD1. Baroreceptor activation showed a significant increase in gain (C57: 5.4 ± 0.3 vs. SOD1: 7.4 ± 0.5 %/mmHg, P < 0.01) in the SOD1 transgenic mice. Heart rate depression in response to electrical stimulation of the left ADN and cervical vagus was comparable between C57 and SOD1, though MAP reduction in response to ADN stimulation is slightly, but significantly increased at 50 Hz in SOD1 animals. Time- domain analysis of HRV did not reveal any significant difference in beat-to-beat variability between SOD1 and C57 (SDNN: C57: 2.78 ± 0.20, SOD1: 2.89 ± 0.27), although frequency-domain analysis uncovered a significant reduction in the low-frequency power component of the HRV power spectral distribution (C57: 1.19 ± 0.11, SOD1: 0.35 ± 0.06, P < 0.001). This study shows that although hSOD1 overexpression does not affect overall baroreflex function, it does potentiate baroreceptor sensitivity and brain stem control of arterial pressure, and reduces low-frequency beat-to-beat variations in HR, without affecting total HRV.
155

Autonome Dysfunktion bei Patienten mit Amyotropher Lateralsklerose

Menze, Ina Margarete 07 December 2022 (has links)
Vor dem Hintergrund, dass die ALS zunehmend als Multisystem- denn als reine Motoneuronerkrankung verstanden wird, stellt nicht-motorische Symptomatik bei ALS-Patienten ein Forschungsgebiet von Interesse dar. Eine genauere Kenntnis darüber kann Diagnostik, adäquate Therapie sowie das pathogenetische Verständnis der ALS verbessern. Ziel der vorliegenden monozentrischen Querschnittsstudie war, nicht-motorischer Symptomatik, konkret der Symptomatik autonomer Dysfunktion bei ALS-Patienten anhand eines multimodalen Ansatzes nachzugehen. Dazu erhoben wir zur Beurteilung klinisch relevanter Symptome einen Fragebogen zu nicht-motorischer Symptomatik (NMSS), einen hieraus abgeleiteten autonomen Subscore sowie ein kognitives Assessment (MoCA), führten eine Herzfrequenzvariabilitäts-Messung zur Beurteilung des kardioautonomen Systems durch und evaluierten die sonographische Querschnittsfläche des Vagusnerven auf Höhe der Schilddrüse als strukturelles Korrelat des autonomen Nervensystems und des Medianusnerven als peripherer Kontrollnerv bei 37 ALS-Patienten und 40 gesunden Kontrollen, rekrutiert zwischen September 2017 und September 2020. Mithilfe der verwendeten Methoden ließ sich keine spezifische, klinisch relevante Beeinträchtigung des autonomen Nervensystems bei ALS-Patienten erheben. Die Scores des Fragebogens zur nicht-motorischen Symptomatik fielen bei ALS-Patienten signifikant höher aus, vorwiegend jedoch aufgrund von Symptomen eigentlich motorischer Art. Bereits wissenschaftlich anerkannte nicht-motorische Symptomatik kognitiver Art ließ sich durch signifikant niedrigere Gesamtpunktzahlen im MoCA von ALS-Patienten im Vergleich zu Kontrollpatienten reproduzieren, was die Bedeutung von nicht-motorischen Symptomen neuropsychiatrischer Art erneut unterstreicht. Der Vagus-Nerv zeigte sich im Vergleich zum Kontrollkollektiv im ALS-Kollektiv sonographisch nicht größenverändert. Beobachtete erhöhte Ruhe-Herzfrequenzen in der Herzfrequenzvariabilitätsmessung können zur weiteren Evaluierung einer postulierten sympathischen Überaktivität bei ALS-Patienten anregen. Multizentrische, longitudinale Studien größerer Fallzahlen sowie methodische Spezifizierungen sind von Nöten, um Symptomen autonomer Dysfunktion bei ALS-Patienten weiter nachzugehen sowie um Testverfahren mit ausreichender Reliabilität und Validität zu generieren.
156

The Effect of Biofeedback on Coping for Patients with Depression

Atkinson, Amber L 01 January 2017 (has links)
Background: Individuals with depression have a higher incidence of comorbidity which significantly decreases their ability to function and increases their utilization of health care. Due to the severity of the economic burden resulting with depression, research is needed to further examine the most effective treatments for depression. Biofeedback is a therapy that teaches patients how to control the physical affects that manifest during depression. Aim: The purpose of this review of literature is to discover the benefits of biofeedback for patients diagnosed with depression. Method: An electronic literature search was conducted using various databases to retrieve articles examining biofeedback as an intervention for patients with depression or depressive symptoms. Results: Studies that used biofeedback as an intervention for depression reported significant physical benefits for patients, including decreased heart rate variability and respiratory rate, as well as improved function. Conclusion: Research indicates that treatments need to have the potential to empower individuals, relieve them of their negative symptoms, relieve their financial burden, and allow them the quality of life they deserve.
157

Improved Physiology and Psychosocial Well-Being for Children with Physical Disabilities Through Virtual Reality Immersion

Fralish, Bethany D 01 January 2017 (has links)
The purpose of this case study was to examine the physiological and psychosocial effects of an immersive virtual reality (VR) system in a female, young adult with right side paralysis following a left hemisphere brain bleed in order to determine the usefulness of immersive VR for children with physical disabilities, in particular, cerebral palsy (CP). The current study consisted of six sessions over a span of three weeks, with each session lasting approximately 45 minutes. Physiological factors (upper body mobility, heart rate variability) were assessed via a hand use questionnaire and a heart rate monitor, while psychosocial factors (e.g. positive mood) were assessed through post-session debriefing discussions with the participant. All measures were completed at each of the six VR sessions, with the exception of the hand use questionnaire, which was administered at baseline, and post-intervention. The VR programs selected were specifically chosen to engage upper body and arm movements. Descriptive analyses and coding of interviews were conducted to examine changes throughout the study sessions. The participant reported an increase in hand mobility and psychosocial well-being, such as improvement in mood, as a result of her participation in the VR sessions. The results of the current study suggest that the use of movement-specific VR programs may be beneficial to children with physical disabilities and CP, although due to the single-subject design of the study, further research is warranted.
158

Comparative Examination of the Empatica E4 to Record Heart Rate Variability Metrics

Rosero, Andres 01 January 2020 (has links)
The increased accessibility of cyber technology has resulted in advancements in international communications and information sharing never seen in human history. With this new age of digital software comes the proliferation of illegal online activity and cyber terrorism. Repercussions of cyber-attacks have ranged from identity theft to leaks of classified state secrets. To combat this threat, the Department of Defense (DoD) established the Cyber Mission Force (CMF) to head operations in the interests of protecting against cyber-attacks. One of the CMF’s initial projects involves the creation of a Performance Assessment Suite (PAS), a training program designed to improve the training of cyber team members via modeling behaviors and physiological data. One of the primary objectives of the PAS is to evaluate the efficacy of select physiological recording equipment in order to implement in cyber training missions. This project serves to determine the viability of the Empatica E4 as an HRV recording device by comparing its quality of data to another, reliable data collection device – the Equivital EQ02 by leveraging a project involving resonance breathing training with police cadets. The results of this project determined that the E4 was unable to compare favorably for some time domain indices to the EQ02 but did have some slight similarities in data with broader time domain metrics.
159

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.
160

Autonomic Nervous System Dysregulation and Cognitive Functioning in Patients with Congestive Heart Failure

Gathright, Emily C. 28 April 2014 (has links)
No description available.

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