Although humans can infer other people’s intentions from their visual actions (Blakemore, & Decety, 2001), it is not well understood how auditory information can influence this process. We investigated whether auditory emotional information can influence the perceived intention of another from their visual body motion. Participants viewed a set of videos which presented point light displays (PLDs) of 10 actors (5 male) who were asked to portray a ‘hero’ or a ‘villain’ character. Based on a 2-AFC design, participants categorised each visual character as having ‘good’ or ‘bad’ intentions. Response accuracy and speed were recorded. Performance on visual-only trials exceeded chance performance suggesting that participants were efficient at judging intentions from PLDs. We then paired auditory vocal stimuli which were associated with either positive (happy) or negative (angry) emotions with each of the PLDs. The auditory stimuli were taken from Belin et al., (2008) and consisted of nonverbal bursts (‘ah’) recorded from 10 actors (5 male). Each vocalisation was randomly paired with a sex-matched PLD (60 PLD-voice combinations). We found that both the categorisation responses and the speed of those responses were affected by the inclusion of the auditory stimuli. Specifically, reaction times were facilitated when the auditory emotion (positive or negative) matched the perceived intentions (good or bad respectively) relative to unisensory conditions. Our findings suggest important interactions between audition and visual actions in perceiving intentions in others and are consistent with previous findings of audio-visual interactions in action-specific visual regions of the brain (e.g. Barraclough et al. 2005).

audio-visual interaction; intention perception; action perception