NCI Dictionary of Cancer Terms
The NCI Dictionary of Cancer Terms features 8,188 terms related to cancer and medicine.
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- REM sleep
- listen (… sleep)
- One of the five stages of sleep. During REM sleep, the eyes move rapidly while closed and dreams occur. REM sleep is the lightest stage of sleep, during which a person may wake easily. During several hours of normal sleep, a person will go through several sleep cycles that include REM sleep and the 4 stages of non-REM (light to deep sleep). Also called rapid eye movement sleep.