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

See Examples For:

non-REM sleep

The findings build on previous research connecting physical activity with non-REM sleep, a stage that includes the deep sleep essential for physical recovery and healthy brain function.

From Science Daily ● Oct. 12, 2026

"Being able to reduce interruptions during the important stages of non-REM sleep by suppressing VGLUT2 activity would be groundbreaking for individuals struggling with disrupted sleep from disorders like insomnia or PTSD."

From Science Daily ● Dec. 13, 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

They also spent 23 percent of their time in slow-wave sleep, which is the deepest kind of non-REM sleep.

From Salon ● Jul. 24, 2021

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