A subject undergoes sleep deprivation followed by recovery sleep. Why does REM sleep duration typically increase during recovery, particularly in the latter half of the sleep period?

💡 Explanation

REM rebound occurs because the brain attempts to compensate for the REM sleep lost during deprivation via increased REM pressure during recovery. Therefore, REM sleep is prioritized, particularly in the later sleep cycles, rather than cortisol or circadian mechanisms directly regulating REM duration after deprivation.

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