NREM sleep

sleep (slēp) a period of rest for the body and mind, during which volition and consciousness are in abeyance and bodily functions are partially suspended; also described as a behavioral state, with characteristic immobile posture and diminished but readily reversible sensitivity to external stimuli.

---

NREM sleep  non-rapid eye movement sleep; the deep, dreamless period of sleep during which the brain waves are slow and of high voltage, and autonomic activities, such as heart rate and blood pressure, are low and regular.

REM sleep  the period of sleep during which the brain waves are fast and of low voltage, and autonomic activities, such as heart rate and respiration, are irregular. This type of sleep is associated with dreaming, mild involuntary muscle jerks, and rapid eye movements (REM). It usually occurs three to four times each night at intervals of 80 to 120 minutes, each occurrence lasting from 5 minutes to more than an hour.

---

Non-rapid eye movement (NREM) sleep

A type of sleep that differs from rapid eye movement (REM) sleep. The four stages of NREM sleep account for 75-80% of total sleeping time.

Mentioned in: Sleep Disorders