Rapid eye movement sleep

Phase of sleep characterized by random and rapid eye movements

Rapid eye movement sleep (REM sleep or REMS) is a unique phase of sleep in all mammals (including humans) and birds and in some reptiles, characterized by random rapid movement of the eyes, accompanied by low muscle tone throughout the body, and the propensity of the sleeper to dream vividly. The core body and brain temperatures increase during REM sleep and skin temperature decreases to the lowest values. The REM phase is also known as paradoxical sleep (PS) and sometimes desynchronized sleep or dreamy sleep, because of physiological similarities to waking states including rapid, low-voltage desynchronized brain waves.

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