Full text is available at the source.
Contribution of the circadian pacemaker and the sleep homeostat to sleep propensity, sleep structure, electroencephalographic slow waves, and sleep spindle activity in humans
How the body clock and sleep pressure influence sleepiness, sleep patterns, slow brain waves, and sleep spindles in people
AI simplified
Abstract
A robust circadian rhythm of REM sleep peaks shortly after the core body temperature's lowest point.
- Sleep episodes of 9.33 hours occurred at all phases of the endogenous circadian cycle over 33-36 days in an environment free of time cues.
- An increase in REM sleep was observed to be sleep-dependent and interacted with the circadian rhythm, resulting in the highest REM sleep values coinciding with habitual wake-time.
- Slow-wave activity decreased while sleep spindle activity increased across all sleep episodes.
- Slow-wave activity in non-REM sleep showed low amplitude circadian modulation that did not align with the circadian rhythm of sleep propensity.
- Sleep spindle activity exhibited a distinct circadian rhythm, peaking at the start of the habitual sleep episode.
- The interaction between circadian and sleep-dependent components of sleep structure supports the consolidation of sleep and wakefulness.
AI simplified