An experimental test of the theory that visual information is stored in the inferotemporal cortex

This experiment employed reversible cold lesions to assess the possible storage functions of inferotemporal cortex (IT) for visual information. Four Macaca fascicularis were chronically implanted with 4 bilateral sets of cryodes which covered dorsal and ventral IT. Animals learned visual discrimination problems while subsections of IT were cooled. Retention was then tested with the previously warm tissue cold as well as with all of IT cold. In addition, an attempt was made to replicate previous studies showing spared retention of visual discriminations with preoperative overtraining. When animals learned a visual discrimination with partial bilateral IT cooling, retention was good when the previously warm tissue was cooled. If learning occurred with partial IT cooling confined to a single hemisphere, retention was lost when the previously warm tissue was cooled. When acquisition occurred without any cooling, retention was severely impaired when IT was cooled, even if animals received 1000 trials of overtraining. The results are attributed to distributed stimulus-analyzing properties of IT.