Designing an Intelligent Agent? Vertical and Horizontal Features Activate Different Face Schemas

Participants rated machine “faces” which varied in terms of color scheme (white on black or black on white), feature shape (round or square), verticality of eyes, verticality of nose, and verticality of mouth. Ratings were made for aggression, friendliness, intelligence, trustworthiness, and attractiveness. Equally proportioned features yielded the most positive ratings, but all features were important in predicting the magnitude of the difference. Trustworthiness ratings appeared to require the most complex facial processing. Design of intelligent agents needs to take into account the minimal features that elicit an anthropomorphic response.