"The finding that sleep-deprived subjects in our experiment rated angry faces as less trustworthy and healthy-looking and neutral and fearful faces as less attractive indicates that sleep loss is associated with more negative social impressions of others. This could result in less motivation to interact socially," says senior author Christian Benedict, associate professor of neuroscience.
"Our participants were young adults. Thus, we do not know whether our results are generalisable to other age groups. Moreover, we do not know if similar results would be seen among those suffering from chronic sleep loss," says Lieve van Egmond.