Audio-visual sound localization in virtual reality

Virtual reality (VR) can be a strong research tool in audio-visual (AV) experiments. It allows us to investigate AV integration in complex and realistic settings. Here, using a VR setup-up in combination with a loudspeaker array, 16 normal-hearing participants were tested on their sound localization abilities.

The virtual environment consisted of a 1:1 model of the experimental environment except with the loudspeaker array replaced by a ring. This ring indicated the height, but not the position of the loudspeakers. The visual component of the stimuli consisted of a ball falling and then bouncing once on the ring after which it disappeared.

As the ball collided with the ring, an impact sound was played from a loudspeaker. Participants were asked to indicate the apparent sound origin, for both congruent and incongruent visual and audio spatial positions ranging from -30 to 30 degrees. The VR visual stimuli in combination with real auditory stimuli were capable of inducing AV integration.

The range of this integration extended, for several participants, over large ranges of AV disparity compared to some earlier studies.