Research

Mixed

Partial sleep deprivation (sleeping <5 hours in 24 hours) has a greater negative impact on cognitive performance and mood than short-term or long-term total sleep deprivation.

Consistently getting less than 5 hours of sleep is more damaging to your brain and mood than staying awake for a full day. Prioritize getting adequate sleep every night over occasional all-nighters.

GoodQualifiesHIGH confidence
partial sleep deprivation appeared to have a considerably greater overall impact on subjects than either short-term or long-term deprivation.
June J. Pilcher et al. · SLEEP · 1996

Why this rating

Meta-analysis, but some subgroup analyses (e.g., partial cognitive) had smaller sample sizes.

Source

Effects of Sleep Deprivation on Performance: A Meta-Analysis

June J. Pilcher et al. · SLEEP · 1996

DOI 10.1093/sleep/19.4.318

Meta-analysis · 19 studiesCited 1,545×
Read the paper
DOI resolved against Crossref · corpus check 2026-06-10

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