Fact
Why vivid dreams come before dawn
Most REM sleep happens in the last third of the night.
Strong evidence1 min readReviewed
Sleep runs in cycles of about 90 minutes. Early cycles are rich in deep sleep; later cycles hold longer and longer stretches of REM, the stage with the most vivid dreams. That is why so many people wake from a bad dream between 3 and 5 in the morning, and why Nightlight is there at exactly that hour.
Sources
- Carskadon & Dement, Normal human sleep: an overview, Principles and Practice of Sleep Medicine, 2017
Evidence label: Strong evidence. What the labels mean.
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