wakefulness
Quick Summary
Wakefulness is a state of being alert and responsive to external stimuli, contrasting with sleep, which involves reduced responsiveness and complex physiological changes. While the exact purpose of sleep remains unclear, it significantly influences overall physiology. Wakefulness is characterized by heightened sensitivity and efficient responsiveness.1
Disorders related to sleep include insomnia, sleep apnea, narcolepsy, circadian rhythm disorders, parasomnias, and restless legs syndrome. Narcolepsy, for instance, is a genetic disorder causing overwhelming daytime sleepiness and can include vivid hallucinations, sleep paralysis, and sudden muscle weakness (cataplexy).23
The alternation between sleep and wakefulness is a fundamental periodicity observed in higher vertebrates, regulated by factors like the circadian pacemaker and homeostatic regulators. The ascending reticular activating system (ARAS) in the brainstem plays a crucial role in maintaining cortical arousal and thus wakefulness.4
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- sleepDevelopmental patterns of sleep and wakefulness
How much sleep does a person need? While the physiological bases of the need for sleep remain conjectural, rendering definitive answers to this question impossible despite contemporary knowledge, much evidence has been gathered on how much sleep people do in fact obtain. Perhaps the…
Read MoreHow much sleep does a person need? While the physiological bases of the need for sleep remain conjectural, rendering definitive answers to this question impossible despite contemporary knowledge, much evidence has been gathered on how much sleep people do in fact obtain. Perhaps the…
Read More - sleepFunctional theories
…so that information achieved in wakeful functioning is most efficiently assimilated. In their specification of functions and provision of evidence for such functions, such theories are necessarily vague and incomplete. The function of stage 2 NREM sleep is still unclear, for example. Such sleep is present in only rudimentary form…
Read More…so that information achieved in wakeful functioning is most efficiently assimilated. In their specification of functions and provision of evidence for such functions, such theories are necessarily vague and incomplete. The function of stage 2 NREM sleep is still unclear, for example. Such sleep is present in only rudimentary form…
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