REM sleep
noun
: 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
Martin GardnerPeople awakened during REM sleep usually report dreams with visual images and storylike narratives.—Lis Harris
Lis Harriscalled also paradoxical sleep, rapid eye movement sleep
compare slow-wave sleep, non-REM sleepExamples of REM sleep in a Sentence
Recent Examples on the Web
How To Sleep To Reduce Alzheimer's Risk The researchers advise people who are concerned about their own risk of Alzheimer's to practice healthy sleep habits that can help ease the transition from light into REM sleep.
—Barbara A. Perry, Newsweek, 27 Jan. 2025
Walker, in fact, explains that one of the by-products of alcohol metabolism is a class of chemicals, known as aldehydes, that are especially prone to impede REM sleep.
—Adam Gopnik, The New Yorker, 20 Jan. 2025
The team observed the opposite during the REM sleep phase, where the norepinephrine levels were consistently low.
—Ars Technica, 20 Jan. 2025
Cycles of REM sleep primarily occur in the last third of the night.
—Lynne Peeples, TIME, 6 Jan. 2025
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Barbara A. Perry, Newsweek, 27 Jan. 2025
Walker, in fact, explains that one of the by-products of alcohol metabolism is a class of chemicals, known as aldehydes, that are especially prone to impede REM sleep.
—Adam Gopnik, The New Yorker, 20 Jan. 2025
The team observed the opposite during the REM sleep phase, where the norepinephrine levels were consistently low.
—Ars Technica, 20 Jan. 2025
Cycles of REM sleep primarily occur in the last third of the night.
—Lynne Peeples, TIME, 6 Jan. 2025
See all Example Sentences for REM sleep
Dictionary Entries Near REM sleep
Cite this Entry
“REM sleep.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/REM%20sleep. Accessed 2 Feb. 2025.
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REM sleep
noun
: 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 (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
Martin GardnerPeople awakened during REM sleep usually report dreams with visual images and storylike narratives.—Lis Harris
Lis Harriscalled also desynchronized sleep, paradoxical sleep, rapid eye movement sleep
compare non-rem sleepLove words? Need even more definitions?
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