The effect of aging, encoding order, and race in contextual face recognition

The ability to recognize faces of cooperators and cheaters is essential to social exchanges. This study investigated the effect of age, encoding order, and race in the recognition of groups of faces tagged with different reputations (trustworthy, untrustworthy or neutral) using an "old/new" recognition task. The encoding duration for each group of four faces was brief (6s). Participants showed lower hit rates and longer reaction time for untrustworthy than trustworthy and neutral faces (all Caucasian faces), but no primacy or recency effects. The second experiment showed that young (18-29 years old) and intermediate-age adults (30-59 years old) had lower hit rates for untrustworthy faces than trustworthy ones, whereas seniors ([less than or equal to] 60 years old) were equally sensitive to all faces. As expected, RT and false alarm rates increased with age. In the third experiment half of the faces to be memorized were Caucasian and half were African (avatars generated with FaceGen software). Participants (34 Caucasian, 36 Afro-Caribbean) recognized the Caucasian faces significantly more accurately than African ones, and trustworthy faces better than untrustworthy ones. Participants tended to recognize faces of their own race better than the other race. Untrustworthy faces of the same race of the participants were better recognized than the other race. The findings suggest that face recognition is not solely based on a stereotypical evolutionary response. but rather on flexible cognitive processes that are sensitive to aging and race, and finely tuned to the changes in the context in which faces were encoded.