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Charles D. West

Bio: Charles D. West is an academic researcher. The author has contributed to research in topics: Apathy & Sleep deprivation. The author has an hindex of 1, co-authored 1 publications receiving 90 citations.

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TL;DR: Sleep-deprived subjects have been able to perform normally on specific tests designed to measure work capacity, psychomotor performance, intellectual acumen, and personality structure, and measurements of the basal metabolic rate, blood sugar, alkaline reserve, blood and urinary adrenal steroids, etc., have not been found to change significantly with sleep deprivation.
Abstract: Introduction There were several reasons for investigating the effects of sleep deprivation in man. One was simply a curiosity about the unusual consequences of prolonged insomnia described by earlier investigators. Kleitman 1 and Tyler 2 cited in detail the hallucinations and "psychotic-like" symptoms that occur under these circumstances and also described subjects who developed short-lived "schizophrenic" psychoses. Psychological alterations, such as inattention, apathy, illusions, and hallucinations, which commonly appear after 36 to 50 hours of wakefulness, have been noted to coincide with an increase in high-frequency, low-amplitude waves on the electroencephalogogram. 3-5 In contrast to such spontaneous psychological disturbances, sleep-deprived subjects have been able to perform normally on specific tests designed to measure work capacity, psychomotor performance, intellectual acumen, and personality structure. 1,8 Measurements of the basal metabolic rate, blood sugar, alkaline reserve, blood and urinary adrenal steroids, etc., have not been found to change significantly with sleep deprivation. 1,5

91 citations


Cited by
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Journal ArticleDOI
TL;DR: Genetic studies suggest that brain mechanisms controlling waking and NREM sleep are strongly conserved throughout evolution, underscoring their enormous importance for brain function.
Abstract: This review summarizes the brain mechanisms controlling sleep and wakefulness. Wakefulness promoting systems cause low-voltage, fast activity in the electroencephalogram (EEG). Multiple interacting neurotransmitter systems in the brain stem, hypothalamus, and basal forebrain converge onto common effector systems in the thalamus and cortex. Sleep results from the inhibition of wake-promoting systems by homeostatic sleep factors such as adenosine and nitric oxide and GABAergic neurons in the preoptic area of the hypothalamus, resulting in large-amplitude, slow EEG oscillations. Local, activity-dependent factors modulate the amplitude and frequency of cortical slow oscillations. Non-rapid-eye-movement (NREM) sleep results in conservation of brain energy and facilitates memory consolidation through the modulation of synaptic weights. Rapid-eye-movement (REM) sleep results from the interaction of brain stem cholinergic, aminergic, and GABAergic neurons which control the activity of glutamatergic reticular formation neurons leading to REM sleep phenomena such as muscle atonia, REMs, dreaming, and cortical activation. Strong activation of limbic regions during REM sleep suggests a role in regulation of emotion. Genetic studies suggest that brain mechanisms controlling waking and NREM sleep are strongly conserved throughout evolution, underscoring their enormous importance for brain function. Sleep disruption interferes with the normal restorative functions of NREM and REM sleep, resulting in disruptions of breathing and cardiovascular function, changes in emotional reactivity, and cognitive impairments in attention, memory, and decision making.

1,101 citations

Journal ArticleDOI
TL;DR: The published PET data describe a very reproducible functional neuroanatomy in sleep, and more detailed explorations of sleep in humans are now accessible to experimental challenges using PET and other neuroimaging techniques, which will contribute to a better understanding of sleep functions.
Abstract: Functional neuroimaging using positron emission tomography has recently yielded original data on the functional neuroanatomy of human sleep. This paper attempts to describe the possibilities and limitations of the technique and clarify its usefulness in sleep research. A short overview of the methods of acquisition and statistical analysis (statistical parametric mapping, SPM) is presented before the results of PET sleep studies are reviewed. The discussion attempts to integrate the functional neuroimaging data into the body of knowledge already acquired on sleep in animals and humans using various other techniques (intracellular recordings, in situ neurophysiology, lesional and pharmacological trials, scalp EEG recordings, behavioural or psychological description). The published PET data describe a very reproducible functional neuroanatomy in sleep. The core characteristics of this 'canonical' sleep may be summarized as follows. In slow-wave sleep, most deactivated areas are located in the dorsal pons and mesencephalon, cerebellum, thalami, basal ganglia, basal forebrain/hypothalamus, prefrontal cortex, anterior cingulate cortex, precuneus and in the mesial aspect of the temporal lobe. During rapid-eye movement sleep, significant activations were found in the pontine tegmentum, thalamic nuclei, limbic areas (amygdaloid complexes, hippocampal formation, anterior cingulate cortex) and in the posterior cortices (temporo-occipital areas). In contrast, the dorso-lateral prefrontal cortex, parietal cortex, as well as the posterior cingulate cortex and precuneus, were the least active brain regions. These preliminary studies open up a whole field in sleep research. More detailed explorations of sleep in humans are now accessible to experimental challenges using PET and other neuroimaging techniques. These new methods will contribute to a better understanding of sleep functions.

630 citations

Journal ArticleDOI
TL;DR: In this article, the developmental psychobiology of sleep regulation is conceptualized within the context of close links to the control of arousal, affect, and attention, and the interactions among these systems are considered from an ontogenetic and evolutionary biological perspective.
Abstract: Throughout early development, a child spends more time asleep than in any waking activity. Yet, the specific role of sleep in brain maturation is a complete mystery. In this article, the developmental psychobiology of sleep regulation is conceptualized within the context of close links to the control of arousal, affect, and attention. The interactions among these systems are considered from an ontogenetic and evolutionary biological perspective. A model is proposed for the development of sleep and arousal regulation with the following major tenets:1. Sleep and vigilance represent opponent processes in a larger system of arousal regulation.2. The regulation of sleep, arousal, affect, and attention overlap in physiological, neuroanatomical, clinical, and developmental domains.3. Complex interactions among these regulatory systems are modulated and integrated in regions of the prefrontal cortex (PFC).4. Changes at the level of PFC underlie maturational shifts in the relative balance across these regulatory systems (such as decreases in the depth/length of sleep and increased capacity for vigilance and attention), which occur with normal development.5. The effects of sleep deprivation (including alterations in attention, emotions, and goal-directed behaviors) also involve changes at the level of PFC integration across regulatory systems.This model is then discussed in the context of developmental pathology in the control of affect and attention, with an emphasis on sleep changes in depression.

610 citations

Journal ArticleDOI
TL;DR: Findings are discussed in relation to a model of sleep loss influencing prefrontal cortex including executive functions involved in the control of attention and emotions that results in tiredness, difficulties with focussed attention, low threshold to express negative affect, and difficulty modulating impulses and emotions.

554 citations

Journal Article
TL;DR: The developmental psychobiology of sleep regulation is conceptualized within the context of close links to the control of arousal, affect, and attention, and a model is proposed for the development of sleep and arousal regulation.
Abstract: Throughout early development, a child spends more time asleep than in any waking activity. Yet, the specific role of sleep in brain maturation is a complete mystery. In this article, the developmental psychobiology of sleep regulation is conceptualized within the context of close links to the control of arousal, affect, and attention. The interactions among these systems are considered from an ontogenetic and evolutionary biological perspective. A model is proposed for the development of sleep and arousal regulation with the following major tenets:1. Sleep and vigilance represent opponent processes in a larger system of arousal regulation.2. The regulation of sleep, arousal, affect, and attention overlap in physiological, neuroanatomical, clinical, and developmental domains.3. Complex interactions among these regulatory systems are modulated and integrated in regions of the prefrontal cortex (PFC).4. Changes at the level of PFC underlie maturational shifts in the relative balance across these regulatory systems (such as decreases in the depth/length of sleep and increased capacity for vigilance and attention), which occur with normal development.5. The effects of sleep deprivation (including alterations in attention, emotions, and goal-directed behaviors) also involve changes at the level of PFC integration across regulatory systems.This model is then discussed in the context of developmental pathology in the control of affect and attention, with an emphasis on sleep changes in depression.

547 citations