KAINIC ACID LESIONS OF THE SUPERIOR OLIVARY COMPLEX - EFFECTS ON SOUND LOCALIZATION BY THE ALBINO-RAT

The ability of rats to localize sounds in space was determined before and after kainic acid lesions of the superior olivary complex (SOC). A nimals were tested with a 45-ms noise burst delivered from loudspeaker s on the right or left of midline. Anatomical data showed that the les ions destroyed neurons in SOC while preserving fibers of passage in th e trapezoid body and other decussating pathways of the auditory brains tem. Animals with either unilateral or bilateral SOC lesions were impa ired in their ability to localize a single noise burst postoperatively . Deficits were also found after unilateral lesions restricted primari ly to the lateral superior olive. SOC lesions resulted in an elevation in minimum audible angles for sound localization.