non-REM sleep

American  

[nahn-rem sleep] / ˌnɑnˈrɛm ˈslip /

noun

1. Physiology. NREM sleep.

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non-REM sleep Scientific  

/ nŏn′rĕm′ /

1. A period of sleep characterized by decreased metabolic activity, slowed breathing and heart rate, and the absence of dreaming. In humans and certain other animals, the sleep cycle occurs in five stages, the first four consisting of non-REM sleep and the last stage consisting of REM sleep. This cycle repeats itself about five times during a normal episode of sleep. In non-REM sleep, Stage I is characterized by drowsiness, Stage II by light sleep, and Stages III and IV by deep sleep. In adult humans, non-REM sleep accounts for about 75–80 percent of total sleep.

2. Also called NREM sleep

3. Compare REM sleep See more at sleep

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Example Sentences

"The more reindeer ruminate, the less additional non-REM sleep they need," says first author and neuroscientist Melanie Furrer of the University of Zurich.

From Science Daily • Dec. 22, 2023

Muller and his colleagues found that rotating wave patterns called spindles that occur during non-REM sleep – when our brains, breathing and heart rate slow – could enable plasticity required for storing memories during sleep.

From Salon • Jul. 29, 2023

Your breathing and heart rate decelerate and your muscles relax as you slip into the second stage of non-REM sleep, where your body temperature drops and your brain waves get slower.

From Seattle Times • Feb. 27, 2023

Sleepwalking and sleep talking, which occur more often during childhood and adolescence, take place during non-REM sleep.

From Scientific American • Jan. 24, 2023

Salas said research suggests that dreams about things that happened at work or home, or about people you know, occur during non-REM sleep, the type of sleep that accounts for about 75 percent of our slumber.

From Washington Post • Jul. 12, 2017