Lesions of the perirhinal cortex do not impair integration of visual and geometric information in rats.

Rats with lesions of the perirhinal cortex and a control group were required to find a platform in 1 corner of a white rectangle and in the reflection of this corner in a black rectangle. Test trials revealed that these groups were able to integrate information regarding the shape of the pool and the color of its walls (black or white) to identify the correct location of the platform. A clear effect of the perirhinal cortex lesions was, however, revealed using an object recognition task that involved the spontaneous exploration of novel objects. The results challenge the view that the perirhinal cortex enables rats to solve discriminations involving feature ambiguity.