Masker–Signal Interaction in a Localization Task with a Moving Sound Source under the Influence of Precedence Effect

Abstract

The precedence effect refers to a group of auditory phenomena related to the ability to localize sound sources in reverberant environment. The precedence effect was investigated using a localization task in the free sound field. The signal consisted of a direct sound (lead) and a moving target sound (lag). Lead–lag delays ranged from 1 to 40 ms. The lead was always stationary (+15°). The moving lag traveled to or from the lead along two paths situated at two locations (from –86° to –52° and from –52° to –86°). The subjects marked the start and end points of the trajectory of the moving sounds. Localization of the start and end points of the lag was compared with localization of the single source. It was found that the lead affected the start and end points of the lag trajectory. The shift depended on the direction of movement. The start points were always shifted in the direction of motion of the lag. The end points were shifted in the opposite direction. The shifts were decreasing as the delay was increasing. The effect of the lag on the lead localization was small.