Prolonged Visual Experience in Adulthood Modulates Holistic Face Perception

Background: Using the well-known composite illusion as a marker of the holistic perception of faces, we tested how prolonged visual experience with a specific population of faces (4- to 6-year-old children) modulates the face perception system in adulthood. Methodology/Principal Findings: We report a face composite effect that is larger for adult than children faces in a group of adults without experience with children faces ("children-face novices''), while it is of equal magnitude for adults and children faces in a population of preschool teachers ("children-face experts''). When considering preschool teachers only, we observed a significant correlation between the number of years of experience with children faces and the differential face composite effect between children and adults faces. Participants with at least 10 years of qualitative experience with children faces had a larger composite face effect for children than adult faces. Conclusions/Significance: Overall, these observations indicate that even in adulthood face processes can be reshaped qualitatively, presumably to facilitate efficient processing of the differential morphological features of the frequently encountered population of faces.