Nonrestorative sleep refers to the experience of sleep as insufficiently refreshing, often despite the appearance of normal sleep according to objective parameters. As a result, a valid and reliable measure of the subjective experience of NRS is required in order to allow for standardization and comparability in its assessment. This thesis reports the results of a study involving the development and validation of a scale to assess NRS, the Nonrestorative Sleep Scale (NRSS). The psychometric properties of the NRSS were assessed in a group of 256 participants recruited from a sleep clinic population. Principal component analysis revealed four domains. The scale demonstrated good internal and test-retest reliability and reasonable validity compared to other measures. Overnight polysomnographic variables were also compared to scores on the scale and a few were found to be weakly correlated with scale scores. These included alpha EEG, sleep efficiency, and REM latency.

Nonrestorative sleep refers to the experience of sleep as insufficiently refreshing, often despite the appearance of normal sleep according to objective parameters. As a result, a valid and reliable measure of the subjective experience of NRS is required in order to allow for standardization and comparability in its assessment. This thesis reports the results of a study involving the development and validation of a scale to assess NRS, the Nonrestorative Sleep Scale (NRSS). The psychometric properties of the NRSS were assessed in a group of 256 participants recruited from a sleep clinic population. Principal component analysis revealed four domains. The scale demonstrated good internal and test-retest reliability and reasonable validity compared to other measures. Overnight polysomnographic variables were also compared to scores on the scale and a few were found to be weakly correlated with scale scores. These included alpha EEG, sleep efficiency, and REM latency.

Narcolepsy is a disabling sleep disorder that is characterized by persistent sleepiness, and cataplexy – an involuntary loss of waking muscle tone. Cataplexy and narcolepsy are caused by the loss of hypocretin containing neurons in the hypothalamus. However, it is hypothesized that dopamine is also involved in sleep and motor control and plays a role in cataplexy. This study investigated how manipulating dopamine affected sleep and cataplexy in narcoleptic mice devoid of hypocretin. We used d-amphetamine to increase endogenous dopamine levels and quinpirole (D2 agonist) to agonize D2 receptor sites. Amphetamine promoted wakefulness while decreasing sleep in wild-type mice, but was less effective in narcoleptic mice. Amphetamine also reduced cataplexy as well as sleep attacks (an indicator of sleepiness) in narcoleptic mice. Quinpirole had no effect on sleep or wakefulness; however, it potently increased cataplexy without affecting sleep attacks in narcoleptic mice.

Sleep appears to play a critical role in regulating daytime functioning in children. However, few child-focused studies have used objective measures of sleep and examined its role in emotional functioning, memory, and attention. This dissertation consisted of 2 studies. Study 1 examined children’s typical sleep and how it correlates with daytime functioning in 32 typically developing children (14 boys, 18 girls), 8 to 12 years of age (M=9.8 y, SD=1.4). Participants wore actigraphs (recording devices that provide information about sleep and activity) for 1 week and then completed tasks to measure emotional functioning, memory, and attention. On average, children slept less than 9 h per night, which is approximately 1 h less than the recommended duration for this age. Older children had shorter sleep durations, higher sleep efficiency, and later sleep onset times. Correlational analyses revealed that within this group of typically developing children, small variations in sleep were associated with statistically significant effects on daytime functioning. Specifically, shorter sleep duration was associated with increased negative affective response, and lower sleep efficiency was associated with poorer performance on a divided attention task. Study 2 involved experimental manipulation of sleep duration in the same sample of children. Following a week of typical sleep, each child was randomly assigned to go to bed 1 h earlier for 4 nights (Extended condition) or 1 h hour later for 4 nights (Restricted condition) relative to their typical bedtime. Each child then completed the opposite condition. Following each condition, emotional functioning, memory, and attention were assessed using objective and subjective measures. The sleep manipulation was effective: the children slept significantly longer in the Extended (M=9.3 h, SD=0.6) versus Restricted (M=8.1 h, SD=0.7) condition, and children were significantly sleepier in the Restricted condition according to parent, child, and research assistant report. Positive affective response, emotion regulation, memory, and aspects of attention were worse in the Restricted, compared to Extended condition. These studies provide evidence that modest variations in sleep can have substantial effects on daytime functioning in children. Clinical implications are discussed, including the importance of identifying sleep problems and promoting healthy sleep habits in children.

No description available.

The purpose of this dissertation was to examine the associations between sleep problems, sleep hygiene and ADHD symptoms in young adults. The first chapter of this dissertation provides an overview of ADHD in adulthood, and a review of the literature that has associated ADHD and sleep problems. This chapter also highlights the need to develop a valid and reliable instrument to assess sleep hygiene. The second chapter presents a manuscript which outlines the development of a new self-report measure of sleep hygiene in young adults. Exploratory and confirmatory factor analyses were used to develop two sleep hygiene scales (substance abuse and poor sleep scheduling) and overall results indicated that the new instrument has sound psychometric properties, as well as good construct and convergent validity. The third chapter presents a manuscript which outlines two empirical studies that examined the associations between sleep problems, sleep hygiene and ADHD symptoms in young adults. Results indicated that young adults with elevated ADHD symptoms reported more sleep problems (specifically insomnia and sleepiness) and poorer sleep hygiene (specifically substance abuse and poor sleep scheduling) than young adults without elevated ADHD symptoms. Young adults with ADHD also reported more sleep problems even after accounting for substance abuse and poor sleep scheduling, suggesting that poor sleep hygiene is not responsible for the sleep problems of young adults with ADHD. The fourth chapter presents a summary of the research findings, as well as a discussion of the methodological limitations and directions for future research. / Thesis (Ph.D, Psychology) -- Queen's University, 2010-01-20 15:27:40.187

Narcolepsy is a disabling sleep disorder that is characterized by persistent sleepiness, and cataplexy – an involuntary loss of waking muscle tone. Cataplexy and narcolepsy are caused by the loss of hypocretin containing neurons in the hypothalamus. However, it is hypothesized that dopamine is also involved in sleep and motor control and plays a role in cataplexy. This study investigated how manipulating dopamine affected sleep and cataplexy in narcoleptic mice devoid of hypocretin. We used d-amphetamine to increase endogenous dopamine levels and quinpirole (D2 agonist) to agonize D2 receptor sites. Amphetamine promoted wakefulness while decreasing sleep in wild-type mice, but was less effective in narcoleptic mice. Amphetamine also reduced cataplexy as well as sleep attacks (an indicator of sleepiness) in narcoleptic mice. Quinpirole had no effect on sleep or wakefulness; however, it potently increased cataplexy without affecting sleep attacks in narcoleptic mice.

There is minimal research into behavioural interventions for typically developing preschoolers (2-5 years of age) with sleep problems. Often these children are not considered as a distinct developmental group and are incorporated into sleep intervention studies for infants or school-aged children. Yet preschoolers do differ in their language, social and cognitive abilities. The present study examines an intervention tailored to the developmental abilities of four preschool children with sleep problems. It utilised positive reinforcement in order to create a less restrictive intervention than those based on extinction alone. This was combined with a range of other behavioural strategies such as parental presence, standard and graduated extinction to reduce a variety of sleep problems. Problems targeted included bedtime refusal, co-sleeping, night waking and a possible diagnosis of sleep terrors. Behavioural interventions effectively reduced sleep problems in all four participants. Parental report demonstrated acceptance of strategies implemented and satisfaction in intervention outcomes.

Traumatic brain injury (TBI) is a major cause of death and disability throughout the world with few pharmacological treatments available for individuals who suffer from neurological morbidities associated with TBI. Cellular and molecular pathological processes initiated at the time of injury develop into neurological impairments, with chronic sleep disorders (insomnia, hypersomnolence) being among the somatic, cognitive and emotional neurological impairments. Immediately post-injury, TBI patients report excessive daytime sleepiness, however, discordant opinions suggest that individuals should not be allowed to sleep or should be frequently awoken following brain injury. To provide adequate medical care, it is imperative to understand the role of acute post-traumatic sleep on the recovery of neurological function after TBI. The aim of this thesis was to examine post-traumatic sleep after experimental TBI, defined as an increase in sleep during the first hours post-injury. In these studies, we non-invasively measured sleep activity following diffuse brain injury induced by midline fluid percussion injury to examine the architecture of post-traumatic sleep in mice. We detected significant injury-induced increases in acute sleep for six hours regardless of injury severity or time of day injury occurred. We found concurrent increases in cortical levels of the sleep promoting inflammatory cytokine interleukin 1-beta. We extended the timeline of post-injury sleep recording and found increases in post-traumatic sleep are distinctly acute with no changes in chronic sleep following diffuse TBI. Further, we investigated if post-traumatic sleep was beneficial to neurological outcome after brain-injury by disrupting post-traumatic sleep. Disruption of post-traumatic sleep did not worsen functional outcome (neuromotor, sensorimotor, cognition) at one week after diffuse TBI. With sufferers of TBI not always seeking medical attention, our final studies investigated over-the-counter analgesics and their effect on post-traumatic sleep and functional outcome. Acute administration of analgesics with varying anti-inflammatory properties had little effect on post-traumatic sleep and functional outcome. Overall, these studies demonstrated translational potential and suggest sleep after a concussion is part of the natural recovery from injury. While disrupting sleep does not worsen outcome, it is in no way beneficial to recovery. Additionally, a single analgesic dose for pain management following concussion plays little role in short term outcome.

This study addressed the lack of knowledge regarding the epidemiology of waking symptoms attributable to the cervico-thoraic spine. Five inter-linked studies were undertaken to investigate the relationships between reports of waking cervical pain, cervical stiffness, headache and scapular pain, cervico-thoracic spine posture in the side lying position and anthropometry. This has culminated in evidence based advice regarding pillow use. / Thesis (PhD)--University of South Australia, 2004.