by Jenny Hok-kun Hsu. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1990. / Bibliography: leaves 118-131. / Acknowledgements --- p.iv / List of Abbreviations --- p.v / Abstract --- p.vii / Chapter Chapter 1: --- Introduction --- p.1 / Chapter Chapter 2: --- Literature Review --- p.6 / Chapter 2.1 --- Some Basic Concepts/Situations of Sleep --- p.6 / Chapter 2.2 --- Visual Classification of Sleep Stages --- p.10 / Chapter 2.3 --- Computer Analysis of Sleep --- p.21 / Chapter 2.4 --- Medilog System --- p.29 / Chapter Chapter 3: --- Aims of the Study --- p.52 / Chapter Chapter 4: --- Methodology --- p.53 / Chapter 4.1 --- Sample --- p.53 / Chapter 4.2 --- Apparatus --- p.55 / Chapter 4.3 --- Procedures --- p.58 / Chapter 4.4 --- Scoring --- p.63 / Chapter 4.5 --- Statistical Methods --- p.66 / Chapter Chapter 5: --- Results --- p.69 / Chapter 5.1 --- Intra-Scorer Agreement --- p.70 / Chapter 5.2 --- Inter-Scorer Agreement --- p.73 / Chapter 5.3 --- Intra-Stager Agreement --- p.79 / Chapter 5.4 --- Stager-Scorer Agreement --- p.84 / Chapter 5.5 --- Normal Group Versus Patient Group --- p.88 / Chapter Chapter 6: --- Discussion --- p.94 / Chapter 6.1 --- General Considerations --- p.94 / Chapter 6.2 --- Reliability of Manual Scoring --- p.96 / Chapter 6.3 --- Reliability of Computer Staging --- p.101 / Chapter 6.4 --- Choice of Method for Statistical Analysis --- p.107 / Chapter 6.5 --- Some Methodological Limitations of This Study --- p.111 / Chapter 6.6 --- Some Considerations Regarding Further Studies --- p.113 / Chapter Chapter 7: --- Conclusions --- p.114 / References --- p.118 / Illustrations --- p.132

Thesis (M.D.)--University of Maryland, 1815. / Microform version available in the Readex Early American Imprints series.

Thesis (doctoral)--Ludwig Maximilians-Universität zu München, 1979.

Thesis (M.S.)--University of Wisconsin--Madison, 1972. / eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.

Sleep and circadian rhythm disruption (SCRD) is frequently found to co-occur in psychotic disorders. This can include a range of phenotypes such as insomnia, circadian delays, deficits in sleep spindles, and sleep-dependent cognitive impairments. However, increasing evidence suggests that psychosis occurs across a continuum of severity within the general population, yet few studies have investigated sleep and circadian rhythms prior to clinical diagnosis. Furthermore, SCRD and psychosis are posited to share underlying neuropathologies and although increasing evidence implicates shared genetic influence, little is known of the shared environmental risk. This thesis investigates sleep and circadian rhythms at multiple levels, from their occurrence in the general population, their disruption in high risk individuals, and a focus on sleep spindle oscillations in the brain. Firstly, the relationship between subjective measures of sleep and circadian rhythms, risk factors for psychosis, and psychotic-like experiences (PLEs) were studied in a large population sample. All three were highly related, with a subset of risk factors showing a strong association to both PLEs and SCRD. Secondly, sleep and circadian rhythms were assessed in individuals at high risk for developing psychosis based upon having a high load of risk factors and sub-clinical psychotic symptoms. High risk individuals showed subjective SCRD but this was not reflected in objective measures assessed by actigraphy and polysomnography. A subset of high risk individuals further showed substantially later melatonin rhythms compared to a low risk group. Thirdly, high and low risk individuals were assessed for measures of declarative and procedural sleep dependent memory consolidation. High risk individuals showed no evidence for sleep dependent cognitive impairment but did show a potential sensitivity in performance to the amount of sleep, not seen in low risk individuals. Finally, recordings in the somatosensory cortex (SCx) of mice were used as a model to explore the spatio-temporal dynamics and functional significance of sleep spindles. Distinct highly localised spindle events were discovered in the anterior SCx, with their complete absence just a fraction of a millimetre away, and their occurrence of which coincided with unique responses to global vigilance states. Together, this work pioneers research into sleep and circadian phenotypes associated with both sub-clinical psychotic symptoms and risk factors for disease and furthers our knowledge of particular sleep processes which could collectively help us to understand why SCRD and psychosis develop.

To detect REM and wake stages in sleep, this study generates feature variables from the correlation of two-channel EOG signals and the amplitude of LEOG signal. By using the VQ method to quantize these signals into different codewords and by calculating the number of appearances of these codewords, we are able to establish a feature vector for every epoch of the recorded EOG signals. Via a three-stage process, the personalized classification accuracy for REM and wake sleep stages are about 95% and 86%, respectively. By combining these personalized classifiers to perform REM and wake stages detection for other unseen individuals, the classification accuracy for REM and wake sleep stages, the classification accuracy become 85% and 92%. However, the sensitivity for the wake stage detection is merely 52%.

Over the last decade a substantial body of research has focused on the consequences of sleep disordered breathing (SDB) in children. This dissertation presents the results of two large laboratory-based studies. / Thesis (PhD)--University of South Australia, 2008.

Thesis (M. Mus.)--Michigan State University. Dept. of Music Therapy, 2008. / Title from PDF t.p. (viewed Sept. 14, 2009). Includes bibliographical references (p. 38-42). Also issued in print.

Background. The consolidation of episodic memory is particularly vulnerable to fluctuations in glucocorticoid levels, both during wakefulness and during sleep. Corticosteroid exposure is associated with changes in endogenous glucocorticoid activity, sleep disruption, episodic memory impairment, and reduced hippocampal volume. This dissertation had two primary aims. The first was to explore the relationship between corticosteroid exposure and sleep-dependent memory processes, including dreaming, with special focus on associations between corticosteroid exposure and (a) night-time glucocorticoid activity and (b) sleep organization. The second was to explore the neuroanatomical foundation for these relationships in young adults with asthma. To achieve these aims, I conducted three studies. Methods. Study 1 (N = 68) used a cross-sectional, matched-sample, quasiexperimental design to compare night-time salivary cortisol levels, memory performance preand post-sleep, sleep organization (measured using polysomnography), and dreaming in groups of asthmatics and non-asthmatics with varying degrees of corticosteroid exposure. Study 2 (N = 23) used a double-blind, randomized placebo-control true experimental design to test, in healthy young adults, the effects of a single 25 mg dose of prednisone on the same outcome measures. Study 3 (N = 19) used a quasi-experimental design to compare hippocampal volume of moderate-to-high corticosteroid-exposed asthmatics with that of matched healthy controls. That study also examined the relationship between (a) night-time cortisol levels and hippocampal volume, (b) night-time cortisol levels and declarative memory performance, (c) hippocampal volume and declarative memory performance. All participants were English-speaking university students, aged 18-39 years. Results. Studies 1 and 2 showed that, relative to healthy controls, night-time glucocorticoid activity was elevated and sleep organization was disrupted in corticosteroidexposed individuals. Furthermore, there were significant inverse associations between glucocorticoid activity and (a) the organization of slow wave sleep (SWS) and rapid-eye movement (REM) sleep, (b) performance on both declarative and procedural memory tasks, and (c) the episodic memory content of dreams. There were significant positive associations between (a) the proportions and the organization of SWS and REM sleep and performance on measures of both declarative and procedural memory, and (b) the organization of REM sleep and the episodic content of dreams. Study 3 data analyses detected significantly smaller hippocampal volume in asthmatics relative to controls. Severity of asthma was inversely related to left hippocampal volume, but corticosteroid exposure alone was not. Furthermore, a smaller hippocampus was associated with better memory performance among healthy controls, but not among asthmatics. Conclusions. The association between the organization of SWS and REM sleep and performance on measures of both declarative and procedural memory lends support to the sequential hypothesis of sleep-dependent memory processing. The current findings also suggest that glucocorticoid activity is associated with (a) dream content, (b) the organization of SWS and REM sleep, and (c) post-sleep memory performance after sleep, and that these relationships may intersect. Although asthmatics did not display memory deficits or aberrant dreaming patterns, their hippocampal volume data, patterns of night-time cortisol, and sleep disruptions suggest further investigation is warranted into the implications of subtle HPA-axis dysfunction and consequent atypical brain development on cognitive function and quality of life in asthmatics, whether exposed to corticosteroid treatment or otherwise.

Thesis (Ph. D.)--Auburn University, 2008. / Abstract. Vita. Includes bibliographical references (p. 57-66).