Precedence effect in children and adults: Effects of heard and unheard echoes on localization accuracy.

Abstract

The precedence effect is thought to facilitate sound localization in reverberant environments through localization dominance. This is demonstrated at short lead‐lag delays, when a single fused auditory image is heard whose perceived location is dominated by the leading source. We studied localization dominance in children ages 4–5 and in adults. Stimuli were brief noise bursts, with lead‐lag delays ranging from 1–100 ms; the lead location varied along the azimuth (−60, −40, −20, 20, 40, 60 deg) and the lag was fixed at 0 deg. Subjects indicated the perceived location(s) of each heard source. Localization accuracy was computed for the lead and lag at each delay. On a separate task, with delays varying randomly, subjects indicated whether they heard one or two auditory events, and echo threshold was obtained. Results show that localization accuracy for the lead declined as delays increased, suggesting that as the lag became more audible its interference in the localization process increased. For most subjec...