Research

Hormonal

The circadian pacemaker significantly modulates the amount of REM sleep, with maximum REM sleep occurring shortly after the minimum of the core body temperature rhythm, and minimum REM sleep occurring during the plateau phase.

If you are concerned about REM sleep deprivation, note that REM sleep is naturally higher in the early morning hours (shortly after the body temperature minimum). Disrupting this phase (e.g., by waking up too early) may disproportionately reduce REM sleep.

StrongSupportsHIGH confidence
A pronounced circadian modulation of REMS was observed... with maximum values of approximately 35% of TST. This maximum was located shortly after the minimum of the endogenous rhythm of core body temperature. Hereafter, REMS dropped sharply with minimum values of approximately 17% of TST at the plateau phase of the core body temperature rhythm.
Derk‐Jan Dijk et al. · Journal of Neuroscience · 1995

Why this rating

Robust experimental design.

Source

Contribution of the circadian pacemaker and the sleep homeostat to sleep propensity, sleep structure, electroencephalographic slow waves, and sleep spindle activity in humans

Derk‐Jan Dijk et al. · Journal of Neuroscience · 1995

DOI 10.1523/jneurosci.15-05-03526.1995

rct · n=8Cited 1,346×
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DOI resolved against Crossref · corpus check 2026-06-10

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