Alterations in pattern equivalence following inferotemporal and lateral striate lesions in rhesus monkeys.

Abstract

Monkeys with lesions of inferotemporal cortex, monkeys with partial lesions of striate cortex, and unoperated controls were trained to discriminate between 2 figures differing with respect to several cues. Then Ss received equivalence tests to determine whether they had utlized these cues. Inferotemporal animals, unlike striate animals, were impaired in discrimination learning. Equivalence test results suggested that for unoperated Ss position of the figure on the plaque was more effective than configuration. For all operated Ss, position of the figure appeared to be even more dominant over configuration than for unoperated controls. These findings suggest that both inferotemporal and striate lesions produce selective impairment in utilizing less salient features of visual patterns.