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Sleep & circadian

REM sleep

DEREM-Schlaf

REM sleep is named for its rapid eye movements. It is a distinct sleep stage with four signatures. Your eyes dart quickly. You dream vividly. Your brain activity is near-waking. And your skeletal muscles go almost fully limp (atonia). REM builds up toward the second half of the night. It supports memory consolidation, emotional processing, and synaptic plasticity (your brain rewiring its connections). In population studies, less REM has been linked to higher all-cause death, cognitive decline, and worse mood.

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Sources

  1. Aserinsky E, Kleitman N. (1953). Regularly occurring periods of eye motility, and concomitant phenomena, during sleep. *Science*doi:10.1126/science.118.3062.273