Sleep facilitates long-term face adaptation Sleep facilitates long-term face adaptation

Adaptation is an automatic neural mechanism supporting the optimization of visual processing on the basis of previous experiences. While the short-term effects of adaptation on behaviour and physiology have been studied exten- sively, perceptual long-term changes associated with adaptation are still poorlyunderstood.Here,we showthat the integrationofadaptation-dependent long-term shifts in neural function is facilitated by sleep. Perceptual shifts induced by adaptation to a distorted image of a famous person were larger in a group of participants who had slept (experiment 1) or merely napped for 90 min (experiment 2) during the interval between adaptation and test com- pared with controls who stayed awake. Participants’ individual rapid eye movement sleep duration predicted the size of post-sleep behavioural adap- tation effects. Our data suggest that sleep prevented decay of adaptation in a way that is qualitatively different from the effects of reduced visual interfer- ence known as ‘storage’. In the light of the well-established link between sleep andmemory consolidation, our findings link the perceptual mechanisms of sensory adaptation—which are usually not considered to play a relevant role in mnemonic processes—with learning and memory, and at the same time reveal a new function of sleep in cognition.