title: The effect of an additional reflection in a precedence effect experiment.
abstract: Studies on the precedence effect typically utilize a two-source paradigm, which is not realistic relative to real world situations where multiple reflections exist. A step closer to multiple-reflection situations was studied using a three-source paradigm. Discrimination of interaural time differences (ITDs) was measured for one-, two-, and three-source stimuli, using clicks presented over headphones. The ITD was varied in either the first, second, or the third source. The inter-source intervals ranged from 0-130 ms. A perceptual weighting model was extended to incorporate the three-source stimuli and used to interpret the data. The effect of adding a third source could mostly, but not entirely, be understood by the interaction of effects observed in the precedence effect with two sources. Specifically, for delays between 1 and 8 ms, the ITD information of prior sources was typically weighted more heavily than subsequent sources. For delays greater than 8 ms, subsequent sources were typically weighted slightly more heavily than prior sources. However, there were specific conditions that showed a more complex interaction between the sources. These findings suggest that the two-source paradigm provides a strong basis for understanding how the auditory system processes reflections in spatial hearing tasks.
authors.affiliation: Waisman Center, University of Wisconsin, 1500 Highland Avenue, Madison, Wisconsin 53705, USA. goupell@umd.edu
authors.forename: Matthew J
authors.initials: MJ
authors.lastname: Goupell
authors.forename: Gongqiang
authors.initials: G
authors.lastname: Yu
authors.forename: Ruth Y
authors.initials: RY
authors.lastname: Litovsky
mesh_terms: D000161:Acoustic Stimulation / Q000379:methods; D000328:Adult; D003463:Cues; D004192:Discrimination, Psychological / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D015588:Observer Variation; D010469:Perceptual Distortion / Q000502:physiology; D011930:Reaction Time / Q000502:physiology; D013017:Sound Localization / Q000502:physiology*; D013997:Time Factors; D055815:Young Adult