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
More than half of people hit the snooze button, a new study finds, which likely disrupts important, restorative REM sleep.
—Tom Gavin, EverydayHealth.com, 30 May 2025
More specifically, both past research and the current study suggest that REM sleep plays a crucial role in restoring the prefrontal cortex's ability to regulate memory and emotions.
—Jenny Lehmann, Discover Magazine, 21 Feb. 2025
Even a single glass can interfere with brain waves and suppress REM sleep.
—Dr. Samanta Dall’agnese, CNBC, 13 May 2025
Fever can also reduce overall REM sleep time and promote bizarre dreams or nightmares.9
6.
—Ann Pietrangelo, Verywell Health, 28 Mar. 2025
See All Example Sentences for REM sleep
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Tom Gavin, EverydayHealth.com, 30 May 2025
More specifically, both past research and the current study suggest that REM sleep plays a crucial role in restoring the prefrontal cortex's ability to regulate memory and emotions.
—Jenny Lehmann, Discover Magazine, 21 Feb. 2025
Even a single glass can interfere with brain waves and suppress REM sleep.
—Dr. Samanta Dall’agnese, CNBC, 13 May 2025
Fever can also reduce overall REM sleep time and promote bizarre dreams or nightmares.9
6.
—Ann Pietrangelo, Verywell Health, 28 Mar. 2025
See All Example Sentences for REM sleep
Cite this Entry
“REM sleep.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/REM%20sleep. Accessed 6 Jun. 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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