non-REM sleep

noun

variants or NREM sleep
: a state of sleep that occurs regularly during a normal period of sleep with intervening periods of REM sleep and is characterized by delta wave brain activity, little dreaming, and a reduced level of autonomic physiological activity
Non-REM sleep is a quiet sleep state. The muscles are relaxed but maintain some tone, breathing is regular, the cerebral cortex generates high-voltage waves, and consumption of energy by the brain is minimal.Jerome M. Siegel
For most people the few dreams found in non-REM sleep tend to have a rather thought-like character. During REM sleep, on the other hand, dreams occur more frequently and usually have a perceptual vividness …Francis Crick et al.
NREM sleep … is crucial to memory retention, and to acquiring and refining our motor skills.David Kamp
compare rem sleep, slow-wave sleep

Examples of non-REM sleep in a Sentence

Recent Examples on the Web Sleep research has shown that parasomnias often arise during the transitions to and from non-REM sleep. Steve Nadis, Discover Magazine, 26 Nov. 2023 Marsupial mammals called echidnas show characteristics of REM and non-REM sleep at the same time. Carolyn Wilke, Smithsonian Magazine, 13 Sep. 2023 The researchers also departed from the traditional approach of examining brain waves in segregated sleep stages—like rapid eye movement (REM) and non-REM sleep—and instead analyzed wave patterns as part of a full continuum of gradual changes that occur during sleep. Lucy Tu, Smithsonian Magazine, 24 Mar. 2023

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'non-REM sleep.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

First Known Use

1963, in the meaning defined above

Time Traveler
The first known use of non-REM sleep was in 1963

Dictionary Entries Near non-REM sleep

Cite this Entry

“Non-REM sleep.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/non-REM%20sleep. Accessed 16 Apr. 2024.

Medical Definition

non-REM sleep

noun
variants or NREM sleep
: a state of sleep that occurs regularly during a normal period of sleep with intervening periods of REM sleep and is characterized by delta wave brain activity, little dreaming, and a reduced level of autonomic physiological activity
Non-REM sleep is a quiet sleep state. The muscles are relaxed but maintain some tone, breathing is regular, the cerebral cortex generates high-voltage waves, and consumption of energy by the brain is minimal.Jerome M. Siegel
NREM sleep … is crucial to memory retention, and to acquiring and refining our motor skills.David Kamp

called also orthodox sleep, S sleep, synchronized sleep

compare rem sleep, slow-wave sleep
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