Perceiving the facial trustworthiness: Facial age, emotional expression, and attractiveness

People can make trustworthiness judgements based on facial characteristics. However, the previous findings regarding whether facial age influences interpersonal trust are inconsistent. Using the trust game, the current study investigated the interactions of facial age with attractiveness and emotional expression in regard to trustworthiness judgements. In Experiments 1 and 2, younger participants were asked to invest in either younger or older faces that were shown for 2,000 and 33 ms, respectively. The results showed that people trust the faces of older people more than they do younger people. There was also an interaction between facial age and attractiveness. Participants invested more money in older faces than in younger faces only when they perceived the faces to be less attractive. However, the interaction between facial age and emotional expression was slightly inconsistent in the two experiments. Participants invested more money in older faces that were shown for 2,000 ms when they perceived the happy and sad emotions, but they invested more money in older faces that were shown for 33 ms when they perceived the happy emotion. These results reveal that people make trustworthiness judgements based on multiple facial cues when they view strangers of different ages.