Effects of visual stimuli on auditory separation of sound images spatially split by synthesized binaural signal

Abstract

In order to clarify the effect of visual stimuli on the spatially split perception of sound images by interaural differences, we conducted spatially split perception experiments under conditions in which visual stimuli were presented on a head mounted display. The auditory stimuli were synthesized binaural signals consisting of two uncorrelated pink noises convolved with the receiver's own head related impulse responses. As manipulated by the listener using the mouse scroll-wheel, the visual and auditory stimuli spread to the left and right in front of the listener, and the listener was made to answer at what point the sound images were spatially split into two. As a result, the detection limit was smaller in the conditions with split visual stimuli than in the condition without visual stimulus. These results suggest that visual stimuli that give the impression of separation reduce the detection limit of the auditorily perceived spatially split sound images.