Brief high frequency tetanization trains reliably induced input-specific long-term potentiation (LTP) in slices of rat perirhinal cortex maintained in vitro. Furthermore, associative interactions between inputs were observed following simultaneous tetanization of separate inputs. This associativity may be mediated via NMDA receptors as LTP was blocked in the presence of APV. These results suggest that LTP may underline participation of perirhinal cortex in memory processes.