WHEN THE INTERFACE IS A FACE

People behave differently in the presence of other people than they do when they are alone. People also may behave differently when designer s introduce more human-like qualities into computer interfaces. In an experimental study we demonstrate that people's responses to a talking -face interface differ from their responses to a text-display interfac e. They attribute some personality traits to it; they are more aroused by it; they present themselves in a more positive light. We use theor ies of person perception, social facilitation, and self-presentation t o predict and interpret these results. We suggest that as computer int erfaces become more ''human-like,'' people who use those interfaces ma y change their own personas in response to them.