REM sleep

American  

noun

Physiology.

1. a recurrent period of sleep, typically totaling about two hours a night, during which most dreaming occurs as the eyes move under closed lids and the skeletal muscles are deeply relaxed.

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REM sleep Scientific  

/ rĕm /

1. Short for rapid eye movement sleep. A period of sleep characterized by rapid periodic twitching movements of the eye muscles and other physiological changes, such as accelerated respiration and heart rate, increased brain activity, and muscle relaxation. REM sleep is associated with activity in the pons of the brainstem; when the pons is eliminated, REM sleep does not occur. REM sleep is the stage of sleep in which most dreaming takes place and is thought to allow for the organization of memories and the retention of learning. REM sleep is the fifth and last stage of sleep that occurs in the sleep cycle, which repeats itself about five times throughout a period of sleep. It is preceded by four stages of non-REM sleep. REM stages become longer with each cycle and account for about 20–25 percent of total sleep in adult humans. In infants, roughly 50 percent of sleep is REM sleep, which is believed to be necessary for the maturation of the central nervous system.

2. Compare non-REM sleep See more at sleep

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Etymology

Origin of REM sleep

First recorded in 1965–70

Example Sentences

Some limited evidence, for instance, has found that those who wake from the deepest phase of the sleep cycle are more likely to make mistakes on math questions than those who wake from REM sleep.

From Seattle Times

But large deficits of REM sleep, no matter your age, can deprive you of its psychological benefits, Dasgupta said.

From Seattle Times

But alcohol suppresses REM sleep and causes sleep disruptions, which will worsen the overall quality of your sleep.

From New York Times

According to a YouTube video documenting the effort, when the participants awoke from REM sleep, five reported dreaming about Coors beer or seltzer.

From Science Magazine

At the time, researchers associated dreaming with REM sleep, a particularly “mindless” state.

From Washington Post