VISUAL AND AUDITORY CORTICAL-LESIONS FOLLOWING ACQUISITION OF AN INTENSITY DISCRIMINATION IN RATS FAIL TO DISRUPT CROSS-MODAL TRANSFER

The effect of visual or auditory decortication on cross-modal transfer of an intensity discrimination was examined in rats. Twenty animals w ere first trained under either visual-auditory (V-A) or auditory-visua l (A-V) cross-modal transfer (CMT) in a shuttlebox using a shock avoid ance pardigm. Prior to the second training session, five of the A-V an imals received auditory ablations and five V-A animals received visual ablations. The other 10 animals served as controls and received sham operations. The results reveal that CMT occurred in both experimental groups following cortical ablations. It is possible that information r egarding stimulus intensity was transferred from a cortical region use d during the original training session to the cortex used in the secon d or retraining session, prior to surgery. Alternatively, it may be th at some subcortical structure (e.g. the amygdala, superior colliculus, or reticular formation) may be involved in CMT of intensity.