Body & HealthFact

You don't sleep one night, you sleep five short ones.

Your sleep runs in cycles of about 90 minutes, typically 4 to 6 per night. Each cycle moves from light sleep through deep sleep into REM sleep, where most dreaming happens. The mix shifts over the night: deep sleep dominates the first cycles, while REM phases grow longer toward morning.

Useful: That is why cutting a night short by two hours costs a disproportionate amount of REM sleep.

Source: en.wikipedia.org

Gehirn Schlaf

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