Cues of fatigue: effects of sleep deprivation on facial appearance.
Level 3 - non-randomized controlled study
Within-subject experimental laboratory study assessing observer ratings
PubMed 23997369 · doi:10.5665/sleep.2964
What was done
Forty observers (20 women, mean age 25 ± 5 years) rated 20 facial photographs on 100-mm visual analog scales for fatigue, sadness, and 10 specific facial cues. The photographic stimuli were obtained from 10 individuals (5 women) photographed at 14:30 under two conditions: after normal sleep and after 31 hours of sleep deprivation preceded by a night with 5 hours of sleep.
What was found
Compared to normal sleep, sleep-deprived faces were rated as having significantly more hanging eyelids, redder eyes, more swollen eyes, darker under-eye circles, paler skin, more wrinkles/fine lines, and droopier mouth corners (effects ranging from b = +3 ± 1 to b = +15 ± 1 mm on 100-mm visual analog scales, P < 0.01). Overall fatigue ratings were related to glazed eyes and to all facial cues affected by sleep deprivation (P < 0.01). Sleep-deprived individuals were also rated as looking sadder than after normal sleep, and sadness was related to looking fatigued (P < 0.01). Ratings of rash/eczema and tense lips were not significantly affected by sleep deprivation.
Why it matters
This study identifies specific facial features around the eyes, mouth, and skin that communicate sleep loss to observers. It demonstrates that acute sleep deprivation alters facial appearance in ways that carry potential social consequences.
Limits
The stimulus set consisted of only 10 photographed individuals, limiting generalizability across different ages, ethnicities, and skin types. The severe sleep deprivation protocol (31 hours of continuous wakefulness) does not reflect typical chronic partial sleep restriction, and static photographs do not capture dynamic facial movements or interactions.
Cited by
- partial Periorbital puffiness and bags under the eyes caused by sleep deprivation are directly due to the pooling and impaired clearance of lymphatic fluid.