UNT Theses and Dissertations - 3 Matching Results

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Effects of a Single Bout of Exercise on Neurocognitive Function following Acute Sleep Loss

Description: Acute sleep loss may lead to elevated fatigue, decreased energy, and diminished cognitive performance. Traditionally, sleep extension is used to restore mood and cognitive function to baseline levels following insufficient sleep, yet this method may not be feasible or preferred. Acute exercise may serve as an affordable and relatively safe intervention to reduce detriments to daytime functioning following sleep loss. The primary purpose of this study was to examine the effects of moderate-intensity aerobic exercise on neurocognitive function following acute sleep restriction. A secondary aim was to examine the effects of exercise in subjective reports of fatigue, energy, and sleepiness following acute sleep restriction. Fifty-six participants, matched by sex, age, and chronotype, were randomly assigned to either an exercise (EX) or seated control (SC) condition. Following a 4-hour sleep restriction protocol, participants completed the oddball paradigm before and after 20 minutes of exercise or stationary sitting. P3 amplitude and latency, arousal, sleepiness, energy, and fatigue were assessed during the experiment. After controlling for pre-test differences, P3 latency was significantly faster following exercise relative to the control group. No significant P3 amplitude differences were observed between conditions. The EX group displayed significant improvements in arousal, sleepiness, energy, and fatigue compared to the SC group. Findings suggest that 20 minutes of moderate-intensity aerobic exercise following acute sleep restriction may improve cognitive processing speeds, as well as improve arousal, sleepiness, energy, and fatigue.
Date: August 2018
Creator: Carmichael, Kaitlyn E.
Partner: UNT Libraries

The Effects of Low-Intensity Exercise on Neurocognitive Function

Description: Acute aerobic exercise exerts a small beneficial effect on cognition. Much of the research to date has focused on cognitive changes following a bout of exercise, while little is currently known about changes in cognitive performance during exercise. The limited research that has been conducted suggests either positive, negative, or no effects on cognitive performance during exercise. Thus, the primary purpose of this study was to examine the effects of low-intensity cycling on cognitive function in college-aged students, indexed by response accuracy, reaction time, P3 amplitude, and P3 latency. Twenty-seven (Mage = 22.9 ± 3.0 years old) college-aged individuals were counterbalanced into low-intensity exercise (EX) and seated control (SC) conditions. During each condition, participants completed a 10-minute resting baseline period, 20 minutes of either sustained cycling or seated rest, and a 20-minute recovery period. Primary outcomes were assessed at 10-minute intervals (5 blocks total) throughout each condition via a modified oddball task. Across time blocks, both conditions exhibited faster reaction times on frequent trials but reduced accuracy to rare trials, suggesting a speed-accuracy tradeoff. There were no differences between conditions in P3 latency whereas a significant reduction in P3 amplitude was observed during the 20-minute exercise period compared to the control condition. Taken together, the results suggest that exercise at lower doses may have minimal influence on behavioral outcomes of cognitive performance but may impact more basic measures of brain function. Information gathered from this study may aid in the development of appropriate exercise prescriptions for populations looking to specifically target cognitive function deficits.
Date: August 2018
Creator: Cleveland, David
Partner: UNT Libraries

Evaluating the Pulse Sensor as a Low-Cost and Portable Measurement of Blood Pulse Waveform

Description: This study was aimed at determining whether the digital volume pulse waveform using the Pulse Sensor can be used to extract features related to arterial compliance. The Pulse Sensor, a low-cost photoplethysmograph, measures green light reflection in the finger and generates output, which is indicative of blood flow and can be read by the low-cost Arduino UNO™. The Pulse Sensor code was modified to increase the sampling frequency and to capture the data in a file, which is subsequently used for waveform analysis using programs written in the R system. Waveforms were obtained using the Pulse Sensor during two 30-s periods of seated rest, in each of 44 participants, who were between the ages of 20 and 80 years. For each cardiac cycle, the first four derivatives of the waveform were calculated and low-pass filtered by convolution before every differentiation step. The program was written to extract 19 features from the pulse waveform and its derivatives. These features were selected from those that have been reported to relate to the physiopathology of hemodynamics. Results indicate that subtle features of the pulse waveform can be calculated from the fourth derivative. Feature misidentification occurred in cases of saturation or low voltage and resulted in outliers; therefore, trimmed means of the features were calculated by automatically discarding the outliers. There was a high efficiency of extraction for most features. Significant relationships were found between several of the features and age, and systolic, diastolic, and mean arterial blood pressure, suggesting that these features might be employed to predict arterial compliance. Further improvements in experimental design could lead to a more detailed evaluation of the Pulse Sensor with respect to its capability to predict factors related to arterial compliance.
Date: May 2016
Creator: Smithers, Breana Gray
Partner: UNT Libraries