Auditory footsteps affect visual biological motion orientation detection

Abstract

This study investigated audiovisual interaction in the perception of the direction of biological motion using point-light walkers (PLW). It continues the work of Vanrie and colleagues (Vanrie et al, 2004 Perception 33 547 - 560) about the bistable character and the perceptual bias of PLW, which has shown that ambiguous PLW are preferably interpreted as being oriented towards the viewer. Each participant made judgements about the direction of a PLW's motion in three conditions: visual, audiovisual, and auditory. It was found that the auditory footsteps simultaneous and congruent with the visual representations diminished, but did not eliminate, the visual bias. The reaction times reveal a strong bimodal facilitation effect, even when both stimuli could be interpreted as incongruent.