The precedence effect: Fusion and localization dominance

Abstract

Fusion and localization dominance are two aspects of processing sounds in reverberant spaces. If a single sound source is perceived when a source and its reflections are presented then a perceptual fusion of the source and reflection has occurred. Localization dominance refers to the spatial location of a sound source and its reflections being dominated by the location of the source. Four listeners were presented a transient sound from one loudspeaker (source) in a sound-deadened room followed a few milliseconds later by the presentation of the transient at another loudspeaker (reflection). The listeners determined how many sound sources were detected (fusion) and the spatial location of these sources (localization dominance). The results will be discussed in terms of the temporal delay between the source and reflection (0.5 to 64 ms), the number of presentations of the source and reflection (1, 3, 6, 7, 9, 12), and three conditions of switching the source and reflection after the sixth presentation: no switch, the location of the source and the reflection were reversed (reversal switch), and the location of the source and reflection were moved in the same direction (lateral switch). [Work suported by NIDCD and AFOSR.]