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Definition of REM sleep
: a state of sleep that recurs cyclically with non-REM sleep several times during a normal period of sleep, is characterized especially by greatly depressed muscle tone, dreaming with vivid imagery, rapid eye movements, and increased neuronal activity in certain brain regions (such as the pons), and typically comprises up to 25% of time spent in sleep
REM sleep, it soon became apparent, occurs in intervals throughout the night, usually four to six times, each lasting from ten minutes to an hour.— Martin Gardner People awakened during REM sleep usually report dreams with visual images and storylike narratives.— Lis Harris
— called also paradoxical sleep, rapid eye movement sleep
— compare slow-wave sleep, non-REM sleepKeep scrolling for more
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Merriam-Webster unabridgedWords at Play
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Time Traveler for REM sleep
The first known use of REM sleep was in 1963
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