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
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
Couples who sleep next to each other might also experience synchronized heart rhythms and have more REM sleep.
—Caroline C. Boyle, USA Today, 28 Mar. 2025
Researchers divided the patients into those who reached REM sleep early (in less than 98 minutes after falling asleep) and those who reached REM sleep late (more than 193 minutes after falling asleep).
—Tom Gavin, EverydayHealth.com, 4 Feb. 2025
See All Example Sentences for REM sleep
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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
Couples who sleep next to each other might also experience synchronized heart rhythms and have more REM sleep.
—Caroline C. Boyle, USA Today, 28 Mar. 2025
Researchers divided the patients into those who reached REM sleep early (in less than 98 minutes after falling asleep) and those who reached REM sleep late (more than 193 minutes after falling asleep).
—Tom Gavin, EverydayHealth.com, 4 Feb. 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 27 May. 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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