ROLE OF AUDITORY CORTEX IN DISCRIMINATION REQUIRING LOCALIZATION OF SOUND IN SPACE

Abstract

Cats were trained to make a response requiring localization of sound in space. Lesions were then made in the cortical projection areas of the auditory system. After bilateral ablation of AI and, in some cases, of All and Ep, a severe deficit in performance was found. In contrast, response to visual cues in the same situation was readily learned, and control animals with ablation of nonauditory cortex retain the sound-localization habit and showed no deficit in performance. Performance improved when the experimental situation was changed so that less accurate localization of sound in space was required and less chance was allowed for a change from the initial direction of a response. Several hypotheses are suggested as to the role of the auditory projection areas in the control of behavior involving localization of sound in space.