Feeling awake does not prove you slept enough
Your sense of sleepiness can level off while your attention keeps getting worse. Feeling used to short nights is not the same as adapting to them.
Make room for a full night of sleep instead of using how alert you feel as the test.
In a lab trial, 14 nights limited to 6 hours in bed led to accumulating cognitive deficits.
Why consider it?
The sleep-restriction experiment involved healthy young adults. The finding concerns accumulated cognitive-performance deficits, which differed by task, not every bodily effect of sleep loss. Participants' subjective sleepiness did not track the continuing deterioration. A controlled laboratory result is not a precise forecast for your schedule.
Read the sources
Source grade A is reproduced from the original work. It does not establish suitability for everyone.
- Van Dongen, Maislin, Mullington & Dinges (2003). The Cumulative Cost of Additional Wakefulness: Dose-Response Effects on Neurobehavioral Functions and Sleep Physiology From Chronic Sleep Restriction and Total Sleep Deprivation. Sleep.
- Lim & Dinges (2010). A meta-analysis of the impact of short-term sleep deprivation on cognitive variables. Psychological Bulletin.
Adaptation: Rewritten in English from the locked Chinese original; retained evidence grade and study limits. Effect sizes quoted from the cited source: estimates are kept in their original comparison and population; observational associations are not described as proven personal gains. r3 AI review: Corrected the intervention to time in bed, not measured sleep; traced the original trial definition.
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