Thesis (M.S.)--West Virginia University, 2000. / Title from document title page. Document formatted into pages; contains viii, 195 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 77-81).

Thesis (doctoral)--Freie Universität Berlin, 1980.

One of two project reports. The other is designated PART A: McMASTER (ON-CAMPUS) PROJECT / <p> It is well known that heart rate is an important physiological parameter. In some cases, continuous monitoring of active subjects is desireable. </p> <p> The report focuses on the feasibility of a miniaturized, portable heart rate monitor. Good artifact rejections, low power consumption small size and ease of use are of primary importance in such design. In order to keep size as low as possible a single cell (1 .5 V) supply voltage is used. </p> <p> A LED - phototransistor type of transducer was chosen for its good artifact rejection and simplicity of application. The transducer clips on the subject's earlobe. Light transmitted through the earlobe is amplitude modulated by the heart (blood) pulses and detected by the phototransistor thus providing electrical signal. </p> <p> In order to keep current drain low, the LED was powered by ~ 1% duty cycle pulses. The rest of the system was designed to comply with the requirements of the transducer. The detected train of pulses were preamplified and the original modulating waveform (heart pulse) reconstructed by a "sample and hold" circuit. The reconstructed signal was amplified by a narrow-band-pass amplifier filter. </p> <p> An astable and two monostable multivibrators perform the necessary timing. Two integrated circuits were also employed: a voltage regulator, to provide stable reference voltages where needed and the output amplifier filter, providing the bulk of the gain. </p> <p> A working prototype was built and suggests that a personalized heart rate monitor is quite feasible. The whole circuit can be integrated, with the exception of few capacitors and perhaps some trimming potentiometers. </p> / Thesis / Master of Engineering (MEngr)

The current study aimed to test sensation seeking as a mediator in the relationship between arousal and aggression. In addition, an experimental design was used to test whether arousal can be manipulated to alter levels of sensation seeking and aggression, both measured behaviorally. A sample of 128 undergraduate students completed state and trait measures of sensation seeking and aggression, and baseline measures of physiology. It was hypothesized that trait sensation seeking would mediate the relationship between baseline physiology and trait aggression. Also, state sensation seeking would mediate the relationship between an arousal manipulation and state aggression. The results failed to support the proposed mediation models. Furthermore, the arousal manipulation was insufficient to result in sustained heart rate differences, and therefore the malleability of state sensation seeking and aggression could not truly be tested. Exploratory analyses supported an interaction between arousal and sensation seeking, such that in individuals low on experience seeking, disinhibition and boredom susceptibility, low heart rate was associated with greater aggression. These findings suggest that arousal and sensation seeking may conjointly predict aggression through moderation rather than mediation, though future studies with improved experimental designs are needed. / Ph. D.

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Via the delivery of blood, heart transfers oxygen and nutrients to various organs and is thus a highly influential for circulatory system. To adapt to the variation of physiological conditions, the intensity and frequency of heart beats change with time. Careful observation finds that the time intervals between heartbeats are often different even if the body is at rest. Such heart rate variability (HRV) has been used to estimate the activity of the autonomic nervous system which can be divided into sympathetic and parasympathetic subsystems both of which can significantly affect the physiology of the human body. As a result, HRV has been used as a physiological indicator to assist doctors in making diagnostic decisions. Many studies have used HRV to analyze the ECG signal via studying the QRS complex waveform to determine the time intervals between R-peaks and analyze the R-R intervals from time and frequency domains. Different from the conventional R-R Interval based approach, this work introduces new HRV feature variables by computing spectrogram of the ECG signal waveform. In particular, based on the harmonics of the spectrum, we introduce the concepts of modes. By find the relative amount of energy associated with each mode and degree-of-energy-concentration associated with each mode, this work introduces two sets of new HRV features. In addition, we also investigate how these variables change with time and the correlations between these features. To demonstrate the potential of the proposed features, the differences of the values of the proposed features are compared for healthy individuals versus OSA patients, young versus old and male versus female. The experimental results show the differences between many of the tested features are statistically significant.

Measuring physiological parameters or vital sign using camera has become popular in recent years. Contact-less monitoring and extraction of vital signs can be important source of information in situations like medical care system and safety control system. This paper presents the implementation of real-time, non-contact method for extraction of vital signs, heart rate in this case. A better face tracking method is used for efficient face detection. This study extends some of the previous works done and have a comparison study with several methods. The developed system used filtering with window over the green channel of the signal and then Converted to frequency domain to analyze the signal to detect heart rate. The developed system achieved high correlation and showed small error while referencing with actual heart signal from ECG. This method delivers better result in better light condition but gives fairly good result on lower light as well.

Thesis (M.S.)--University of Hawaii at Manoa, 2006. / Includes bibliographical references (leaves 92-96). / 111 leaves, bound ill. (some col.) 29 cm

Thesis (M.S.)--University of Hawaii at Manoa, 2006. / Includes bibliographical references (leaves 78-82). / xiii, 82 leaves, bound ill. 29 cm

The present study addressed cognitive biases in anxiety and depression using the emotional Stroop task, and explored both the affective space and autonomic underpinnings of these disorders. In previous studies, anxiety has been associated with both an attentional bias toward threat information and low cardiac vagal control, as reflected in heart rate variability (HRV) indices. Depression has been linked to a memory bias for negative information; however, findings of low HRV for depression are mixed. The high comorbidity of these disorders renders such findings as difficult to interpret. In the present study, it was hypothesized that the negative affect groups (anxious, depressed, comorbid anxious/depressed) would have lower vagally mediated HRV across tasks compared to the control group and that the anxiety and depression groups would show biases for group specific words on the Stroop task. Results for the Stroop tasks generally support previous findings of an attention bias in anxiety. The comorbid anxiety/depression group generally showed lower vagal control across tasks compared to the other groups, although comparisons between the "pure" anxiety and depression groups and the controls were not significant. It is suggested that this is because the comorbid group had higher depression and anxiety than either of the "pure" groups. / Master of Science