Why are you smiling? In a strategic context, people's affective responses reflect the meaning of android's facial expressions.

Facial expressions play an important role in human emotional communication. Observers' reactions to facial expressions can be simple (e.g., smiling to a smile). However, they can also reflect the contextual meaning of an expression (e.g., smiling to an opponent's frown). Our current study provides evidence for contextual modulation of human responses to facial expressions of a hyper-realistic android. Such modulation occurred when human participants engaged in a strategic game with or against a facially expressive robot. These findings suggest a high level of sophistication in facial communication between humans and robots that can be utilized in future robot design to promote natural social rapport with their users.