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Motor neuron inhibition prevents acting out vivid dream sequences physically. The figure is taken from NIH, which is linked in full on this page. Every fact on Mondo Knows names its source rather than repeating an unsourced claim.

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The brain paralyzes major muscles during REM dream sleep

Motor neuron inhibition prevents acting out vivid dream sequences physically

During rapid eye movement sleep, the brainstem sends inhibitory signals to motor neurons in the spinal cord, causing temporary muscle paralysis called atonia. This protective safety mechanism keeps sleepers from physically acting out their vivid dreams while dreaming.

Where this comes from

NIH

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Tags: sleep, rem, muscles

The brain paralyzes major muscles during REM dream sleep: the short answers

Where does this come from, and can I check it?: Motor neuron inhibition prevents acting out vivid dream sequences physically. The figure is taken from NIH, which is linked in full on this page. Every fact on Mondo Knows names its source rather than repeating an unsourced claim.
Is this really a human body fact?: Yes. It sits on the Human Body shelf, one of 1,090 sourced facts grouped into space, animals, the human body, history, science and more. Category pages collect every fact in the same field.
What else can I read about it?: The links under the fact point to a quiz, game, puzzle or calculator on the same subject, and the shelf below shows related facts. The wording here is original, and quoted phrases are marked as quotations.