Engineering Commons^™

Autonomic Activity In Gulf War Veterans Using Heart Rate And Systolic Blood Pressure Variability, Maryann S. Fam

Theses

Heart rate variability (HRV) describes variations of heart rate and is attributed to cyclic fluctuations in autonomic tone. The different methods of heart rate variability analysis allow for a non-invasive assessment of autonomic activity. This study analyzes the heart rate variability through both frequency domain methods and joint time-frequency domain methods which were executed through the LabVJEW graphical programming language. These algorithms were utilized to assess autonomic nervous system activity in Gulf War veterans with no health complaints versus Gulf War veterans with chronic fatigue syndrome. The heart rate variability analysis was obtained from acquired measurements of heart rate and …

Measurement Of The Baroreceptor Sensitivity Index (Brsi) In The Frequency Domains, Tanvir Raquib

Theses

Time domain analysis for calculating the Baroreceptor Sensitivity Index (BRSI) did not always provide an accurate result. It also had another limitation in that it could not show the influence of the autonomic nervous system for different subjects. The correlation coefficient is a mechanism that was used to either accept or reject the BRSI values in the time domain but the correlation coefficient values changed drastically depending on how many sample points were selected for the calculation.

On the other hand, frequency domain analysis for the BRSI calculation was relatively easier and provided more accurate information compared to the time …

Investigation Of Pathophysiologic Trends In Caucasian And Afro-American Hypertensives By Means Of Heart Rate Variability Recording During Upright Tilt-Table Testing, Jose F. Torrealba

Theses

The incidence of hypertension is more prevalent among the Afro-American population than the Caucasians and there is not a satisfactory explanation for this discrepancy.

Heart Rate Variability (HRV) has been demonstrated to reflect the relative activities of the sympathetic (SMP) and parasympathetic (PSMP) divisions of the autonomic nervous system (ANS).

This study consisted in comparing the HRV, as well as the blood pressure (BP) of four different groups during up-right tilt table testing. The subjects were grouped by age, gender, race and health condition. Analysis in time and frequency domain was applied to the data. In the frequency domain, the …

Using Heart Variability To Measure The Effects Of Manual Medicine On Autonomic Activity, Michael Zullow

Theses

A pilot study was performed to test the theory that manual medicine techniques known as the CV4 (compression of fourth cerebral ventricle) maneuver and a sacral hold/iliac bridge hold combination increase parasympathetic activity. Manual medicine techniques are widely practiced by Doctors of Osteopathy and Chiropractors to treat physical and mental health problems. Those who have received manual therapy have reported to experience less pain, better mobility, and a greater feeling of relaxation. To help us learn about the effects of manual therapy, autonomic activity was measured scientifically rather than subjectively in this study by monitoring respiration rate and heart rate, …

Bilinear Time-Frequency Representations Of Heart Rate Variability And Respiration During Stress, Rindala Saliba

Dissertations

Recently, joint time-frequency signal representation has received considerable attention as a powerful tool for analyzing a variety of signals and systems. In particular, if the frequency content is time varying as in signals of biological origin which often do not comply with the stationarity assumptions, then this approach is quite attractive. In this dissertation, we explore the possibility of better representation of two particular biological signals, namely heart rate variability (HRV) and respiration. We propose the use of time-frequency analysis as a new and innovative approach to examine the physical and mental exertion attributed to exercise. Two studies are used …

Signal Processing Techniques In Heart Rate And Systolic Arterial Blood Pressure Variability Studies, Christopher O'Bara

Theses

Power spectral analysis of heart rate and systolic arterial blood pressure variability provides a window to the activity of the autonomic nervous system. To derive power spectra from raw blood pressure and electrocardiogram signals, many steps of signal processing must be performed. Most popular methods of spectral analysis require evenly spaced samples; therefore interpolation and resampling techniques must be used.

The results of the present study indicate that different interpolation techniques result in spectral distortions that vary depending upon the interpolation methods used as well as physiological parameters such as heart and respiration rate. Different interpolation methods applied to heart …

Development Of A Multi-Lead Trans-Thoracic Impedance Pneumograph For Heart Rate Variability Studies, Curtis Bashford

Theses

In this study, a device that measures respiratory tidal volume and ECG for use in heart rate variability studies, was designed, built and tested. The device developed is a Multi-Lead Trans-Thoracic Impedance Pneumograph, which determines tidal volume on a breath by breath basis, utilizing both hardware and software. It uses standard ECG electrodes which provide increased comfort and inability to the subject over traditional spirometry methods. The device operates similar to traditional bipolar impedance pneumographs except that instead of only one lead (electrode pair), four leads are acquired simultaneously using time-division multiplexing; providing data from different locations and vectors on …

Measurement Of The Reaction To Stress And Meditation Using Brain Wave Coherence And Heart Rate Variability, Christopher B. King

Theses

Measurement of physiological parameters associated with the stress response and the relaxation response caused by various forms of meditation can provide valuable information about the reaction of the body to the mind and to the external environment.

This study used two different techniques to evaluate physiological parameters. The first part examined the meditation response by recording the EEG and calculating the coherence between brain waves originating from different parts of the brain. It was found that high levels of coherence in the alpha portion of the EEG frequency band coincided with a restful state associated with the relaxation response. In …

Influences Of Cardiac And Respiratory Parameters On Heart Rate Variability, Melissa Leifer

Theses

Heart rate variability is a result of variation in the activity of the sympathetic and parasympathetic nervous systems. Methods have been developed to determine the level of parasympathetic activity by observing the heart rate variability spectrum. Most of the previously published research uses only level of parasympathetic activity and respiratory rate to draw conclusions about the interactions of the autonomic nervous system with physiological parameters. In order to gain a complete understanding of the autonomic nervous system and the mechanisms responsible for heart rate variability, respiratory volume, cardiac variables and pulmonary variables need to be considered. In addition, amount of …

Heart Rate Variability Study Using Phase Response Curve, Peizhuan Zhang

Dissertations

A noninvasive phase resetting experiment on human subjects was investigated. The phase response curve was estimated and was used to demonstrate cardiac phase resetting due to a vagal input. The estimated running phase response curve showed that the cardiac cycle resetting depended on the time and the amplitude of the vagal stimulation. The phase response curve was then studied using time circle analysis, topological analysis and nonlinear dynamics analysis. Also phase entrainment and stimulus frequency dependence of the phase response were evaluated. Further, the Van Der Pol model, Generalized Additive model and Knight and Peskin's model were used to simulate …