Human Body

Nerves and Senses

What is REM sleep?

Almost all dreams occur during rapid eye movement (REM) sleep. It appears that the content of dreams is stored in short-term memory and cannot be transferred into long-term memory unless they are somehow articulated. Sleep studies show that when individuals who believe they never dream are awakened at various intervals during the night they are in the middle of a dream.

REM sleep is rapid eye movement sleep. It is characterized by faster breathing and heart rates than NREM (non-rapid eye movement) sleep. The only people who do not have REM sleep are those who have been blind from birth. REM sleep usually occurs in four to five periods, varying from five minutes to about an hour, growing progressively longer as sleep continues.


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