Concurrent discrimination learning of monkeys after hippocampal, XXXX .

@entity1 @entity227 @entity131 @entity75 @entity16
Ablations of anterior inferotemporal cortex in monkeys are known to impair learning when discriminations between members of several pairs of objects are taught concurrently. This deficit has been attributed to a loss of @entity227 . But ablations of hippocampus have also been shown to impair retention, and this impairment transcends the @entity227 . Therefore, in the first of two experiments, we compared the behavioral effects of @entity75 with those of either hippocampus, entorhinal area, or fornix, using a visual concurrent discrimination task. Monkeys with either @entity131 were impaired, while those with fornix sections were not. However, ablations of hippocampus included inadvertent damage of the inferotemporal cortex. Therefore, in the second experiment, behavioral effects of @entity75 were compared with those of hippocampus (without additional @entity16 ) on the concurrent task in both @entity227 . In the visual mode, monkeys with hippocampal removals were as impaired as those with inferotemporal ablations. In the tactual mode, however, hippocampal, but no inferotemporal, ablations were followed by a deficit. Our results, taken together with other existing evidence, emphasize the role of the hippocampus in mediating associative learning in more than one modality. These results, obtained with non- @entity1 primates, are in line with clinical findings.
