MEMORY IMPAIRMENT ON A DELAYED NON-MATCHING-TO-POSITION TASK AFTER LESIONS OF THE PERIRHINAL CORTEX IN THE RAT

Previous research conducted in monkeys and rats has established that t he perirhinal cortex is critically involved in object- or stimulus-rec ognition memory, whereas other research suggests this region may contr ibute to memory for object discriminations. These findings do not rule out the possibility that the perirhinal cortex plays a more general r ole in memory. The present experiment addressed whether selective lesi ons of the perirhinal cortex would result in a delay-dependent deficit on a test of memory that did not involve stimulus recognition or obje ct memory. Rats with bilateral perirhinal lesions were tested on a del ayed non-matching-to-position task. Lesions of the perirhinal cortex d id not interfere with acquisition or performance at short (0-4 s)-dela y intervals, but lesions did impair performance at longer delays. It i s suggested that the perirhinal cortex is involved in maintaining repr esentations of trial-specific information over time.