Effects of spatial visual information and head motion cues on auditory spatial judgments

Virtual audio systems are commonly used today to create auditory environments for various listening tasks. The dimensions and absorption characteristics of the surrounding real visual space often do not match the virtual auditory listening space. This mismatch in spatial information has been shown to have a small or negligible effect in the perceived direction of sound sources. However, spatial cues can have a large effect on perceived auditory distance. The most veridical auditory spatial renderings are ones that match the visual space around the observer. Several experiments were conducted to investigate the effects of visual spatial information and head motion cues on perceived auditory distance. In the first experimental condition, naive observers were deprived of all visual cues while making judgments on the egocentric distance of sound sources played over loudspeakers. In the second condition, subjects were presented with mismatched visual and auditory spatial cues via a manikin. The acoustic manikin was either non-moving or would rotate in correlation with the listener’s head motion. In the last (control) condition, sound sources were presented from loudspeakers with matching visual and auditory cues. The effects of the visual spatial cues and head motion cues on auditory distance judgments will be described.