Final answer:
During REM sleep, body paralysis occurs to prevent individuals from physically acting out their dreams.
Step-by-step explanation:
During the stage of REM (Rapid Eye Movement) sleep, body paralysis occurs. REM sleep is the stage of sleep in which most dreaming occurs. During this stage, the brain is highly active, but the body experiences temporary paralysis, known as REM atonia. This paralysis is necessary to prevent individuals from physically acting out their dreams.
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