Rapid eye movement sleep

Rapid eye movement (REM) sleep is a stage of sleep characterized by the rapid and random movement of the eyes. Rapid eye movement sleep is classified into two categories: tonic and phasic.[1] It was identified and defined by Nathaniel Kleitman and his student Eugene Aserinsky in 1953. Criteria for REM sleep includes rapid eye movement, low muscle tone and a rapid, low-voltage EEG; these features are easily discernible in a polysomnogram,[2] the sleep study typically done for patients with suspected sleep disorders.[3] REM sleep typically occupies 20–25% of total sleep, about 90–120 minutes of a night's sleep. REM sleep is physiologically different from the other phases of sleep, which are collectively referred to as non-REM sleep (NREM sleep). Physiology[edit] Polysomnographic record of REM Sleep. Theories about the function(s) of REM sleep[edit] While the function of REM sleep is not well understood, several theories have been proposed. Memory-related theories[edit] Shift of gaze[edit]

Insomnia Insomnia, or sleeplessness, is a sleep disorder in which there is an inability to fall asleep or to stay asleep as long as desired.[1][2] While the term is sometimes used to describe a disorder demonstrated by polysomnographic or actigraphic evidence of disturbed sleep, this sleep disorder is often practically defined as a positive response to either of two questions: "Do you experience difficulty sleeping?" or "Do you have difficulty falling or staying asleep?"[2] Those who are having trouble sleeping sometimes turn to sleeping pills, which can help when used occasionally but may lead to substance dependency or addiction if used regularly for an extended period.[6] §Classification[edit] §DSM-5 criteria for insomnia[edit] The DSM-5 criteria for insomnia include the following:[12] Predominant complaint of dissatisfaction with sleep quantity or quality, associated with one (or more) of the following symptoms: Difficulty initiating sleep. In addition, §Types of insomnia[edit] §Cortisol[edit]

International Classification of Sleep Disorders The International Classification of Sleep Disorders (ICSD) is "a primary diagnostic, epidemiological and coding resource for clinicians and researchers in the field of sleep and sleep medicine."[1] It is produced by the American Academy of Sleep Medicine, in association with the European Sleep Research Society, the Japanese Society of Sleep Research, and the Latin American Sleep Society. The ICSD was first published in 1990.

Narcolepsy Fact Sheet See a list of all NINDS Disorders Get Web page suited for printing Email this to a friend or colleague Request free mailed brochure Narcolepsia PDF version (311 KB) Table of Contents (click to jump to sections) What is narcolepsy? Narcolepsy is a chronic brain disorder that involves poor control of sleep-wake cycles. Narcolepsy can greatly affect daily activities. Contrary to common beliefs, people with narcolepsy do not spend a substantially greater proportion of their time asleep during a 24-hour period than do normal sleepers. For most adults, a normal night's sleep lasts about 8 hours and is composed of four to six separate sleep cycles. For normal sleepers a typical sleep cycle is about 100 to 110 minutes long, beginning with NREM sleep and transitioning to REM sleep after 80 to 100 minutes. Who gets narcolepsy? Narcolepsy affects both males and female equally and appears throughout the world. What are the symptoms? Excessive daytime sleepiness (EDS) Cataplexy Sleep paralysis Obesity