On posture as a modality for expressing and recognizing emotions

The aim of this paper is to promote posture as an important tool for controlling and monitoring the interaction between user and technology. This form of bodily expression of affects presents two facets of interest to our community: (a) It is a powerful modality of communication. As evidence, we summarize some of our previous studies showing how systems can be trained to accurately recognize emotions, even across different cultural backgrounds; (b) Body postures have been shown to have a powerful regulatory role on emotions. This opens the door to the development of systems that, by involving the body of its users, can induce specific affective states and therefore improve user engagement. To support our discussion, we briefly review a very preliminary study showing how incorporating full-body movements in the control of a game results in users reporting a higher sense of engagement. We hypothesize that involving more degrees of freedom in the control of the game facilitated the expression of associated affective states (e.g., excitement) which in turn resulted in the participant experiencing those states more fully.