COVERT SPATIAL ORIENTING IN AUDITION - EXOGENOUS AND ENDOGENOUS MECHANISMS

Covert orienting in hearing was examined by presenting auditory spatial cues prior to an auditory target, requiring either a choice or detection response. Targets and cues appeared on the left or right of Ss' midline. Localization of the target in orthogonal directions (up vs. down or front vs. back, independent of target side) was faster when cue and target appeared on the same rather than opposite sides. This benefit was larger and more durable when the cue predicted target side. These effects cannot reflect criterion shifts, suggesting that covert orienting enhances auditory localization. Fine frequency discriminations also benefited from predictive spatial cues, although uninformative cues only affected spatial discriminations. No cuing effects were observed in a detection task.