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Sleep architecture

“Sleep architecture” refers to the stages of a normal sleep cycle. It comprises REM sleep and the three stages of non-REM (NREM) sleep.

Our evidence-based analysis on sleep architecture features 1 unique references to scientific papers.

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Summary of Sleep architecture

Sleep architecture refers to the stages of a normal sleep cycle. It comprises REM sleep, which last 10 to 60 minutes, and the three stages of non-REM (NREM) sleep: N1 lasts minutes, just after falling asleep; N2 is a bit deeper sleep that lasts 10 to 60 minutes; and N3 is a deep sleep that lasts 20 to 40 minutes.

There used to be four NREM stages, but since no physiological or clinical differences could be found between N3 and N4, in 2007 the American Academy of Sleep Medicine combined these two stages.[1]

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