It's about 2.30pm and you're ready for your photo shoot. It's not exactly vogue - you're given a dark grey T-shirt to wear, have your hair pulled back, and you're not allowed any make-up. You take a seat, look straight into the camera and you're told to 'relax your face.' But at least you're feeling refreshed - for the two previous nights you've had a full 8 hours of sleep. The instructions from the researchers were to get to sleep sometime between 10pm and midnight, and to wake up somewhere between 6-8am.
So, when you come back to the lab a week later, things are a little different. This time you've been instructed to get 4 hours of sleep over the past two nights. Your instructions were to go to bed sometime from midnight to 2am and get up between 4-6am! Now, it's 2.30pm again and you're not so ready for the photo shoot: same T-shirt, same 'relaxed' face with no make-up.
So what was happening with these photos? And the photos taken of the 24 other people taking part in this study?
Well, you're being rated - by 122 members of the public (they even get a movie ticket for taking part). These people are rating your face on seven-point scale for:
sociability (How much would you like to socialise with this person?)
trustworthiness (How trustworthy is this person?)
attractiveness (How attractive is this person?)
health (How healthy is this person?)
sleepiness (How sleepy is this person?)
The raters were significantly less willing to socialize with the sleepy-you (compared to the refreshed-you). They also rated sleepy-you as less attractive and less healthy. In fact, the only thing that was unaffected by sleepiness was trustworthiness - sleepy-you was rated just as trustworthy as refreshed-you.
Sundelin T, Lekander M, Sorjonen K, Axelsson J. 2017 Negative effects of restricted sleep on facial appearance and social appeal. R. Soc. open sci. 4: 160918.