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Stages of Sleep

Table of Contents


Topic Overview

Sleep stages are divided into non–rapid eye movement (non-REM) and rapid eye movement (REM).

Non-REM (NREM) sleep

Non–rapid eye movement (NREM) sleep has 3 stages:

REM (R) sleep

Rapid eye movement sleep is deeper than non-REM sleep. During REM sleep:

You do most of your dreaming during REM sleep. But your brain paralyzes your muscles so you do not act out the dreams.

During sleep, a person usually progresses through the 3 stages of non-REM sleep before entering REM sleep. This takes about 1 to 2 hours after falling asleep. The cycle is repeated three to four times each night. An adult spends more time in NREM sleep than in REM sleep. An infant usually spends about half of the sleeping time in NREM and half in REM stages.


Credits for Stages of Sleep

Current as of: July 6, 2021

Author: Healthwise Staff
Medical Review: Anne C. Poinier MD - Internal Medicine
Adam Husney MD - Family Medicine
Hasmeena Kathuria MD - Pulmonology, Critical Care Medicine, Sleep Medicine


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