Does being very tired make it harder for you to tell if someone is angry or happy?

Study Objectives: Investigate the impact of sleep deprivation on the ability to recognize the intensity of human facial emotions.
Design: Randomized total sleep-deprivation or sleep-rested conditions, involving between-group and within-group repeated measures analysis.
Setting: Experimental laboratory study.
Participants: Thirty-seven healthy participants, (21 females) aged 18–25 y, were randomly assigned to the sleep control (SC: n = 17) or total sleep deprivation group (TSD: n = 20).
Interventions: Participants performed an emotional face recognition task, in which they evaluated 3 different affective face categories: Sad, Happy, and Angry, each ranging in a gradient from neutral to increasingly emotional. In the TSD group, the task was performed once under conditions of sleep deprivation, and twice under sleep-rested conditions following different durations of sleep recovery. In the SC group, the task was performed twice under sleep-rested conditions, controlling for repeatability.
Measurements and Results: In the TSD group, when sleep-deprived, there was a marked and significant blunting in the recognition of Angry and Happy affective expressions in the moderate (but not extreme) emotional intensity range; differences that were most reliable and significant in female participants. No change in the recognition of Sad expressions was observed. These recognition deficits were, however, ameliorated following one night of recovery sleep. No changes in task performance were observed in the SC group.
Conclusions: Sleep deprivation selectively impairs the accurate judgment of human facial emotions, especially threat relevant (Anger) and reward relevant (Happy) categories, an effect observed most significantly in females. Such findings suggest that sleep loss impairs discrete affective neural systems, disrupting the identification of salient affective social cues.

Source: “Sleep Deprivation Impairs the Accurate Recognition of Human Emotions” from SLEEP

This may shock you but I actually recommend this book. It was his first one and I got something out of it. I’m not recommending his show or any of his subsequent books.

Related posts:

Does having a lot on your mind reduce your ability to experience emotion?

Why are women better at detecting non-verbal emotion?

Do the emotions related to how you received money affect how you spend that money?

Are you less likely to get in a car accident if your GPS unit’s voice matches your own emotional state?

If you’re emotionally distant, where should you live?

Feeling tired and burned out? Did you make a lot of decisions today?