A study of human performance in recognizing expressive hand movements

This paper presents a study on human performance in recognizing affective expressions conveyed through movements of hand-like structures. One movement sequence, closing and opening the hand, was performed by a demonstrator in 3 sets of 5 repeated trials, each set intending to convey a different affective expression. Three different expressions, sadness, happiness and anger, were considered. Expressive movement animations were replicated with a human-like hand model, a stick hand model and with a model resembling a palm frond structure. The structures tested have identical kinematics but different physical appearance. The ability of a human to correctly identify the intended expressive movements performed on these different structures was tested with 66 users viewing videos of the animated structures and reporting via an online questionnaire. Results show that anger is reliably perceived by observers from animated movements on different structures, while the other emotions are easily misperceived. The physical appearance of the structure has some impact on perception performance, but was not found to be statistically significant in this study. Furthermore, analyzing the participants' responses in the context of the valence-arousal model of emotion shows that the subjects were able to recognize the arousal component of the affective hand movements across all structures.