It is now clear that the perirhinal cortex has functions that are distinct and dissociable from those of the hippocampus, and thus recent research has focussed on the question of how best to characterise these functions. I will present a model of perirhinal cortex function that accounts for extant data, and makes novel predictions, regarding the effects of perirhinal cortex lesions on visual discrimination (Bussey & Saksida 2002). The fundamental premise of the model is that perirhinal cortex can be thought of as an extension of the hierarchically organised ventral visual stream for object identification. The perirhinal cortex is thought to reside at the top of this hierarchy, containing complex conjunctive visual representations that are important for resolving feature ambiguity in visual discriminations. I will describe novel predictions, generated by the model, which have been subsequently tested in our experiments with rhesus monkeys (Bussey et al. 2002, 2003). These computer simulations and monkey experiments reveal a perceptual-mnemonic function for perirhinal cortex, and suggest that perception and memory may not be neatly organised into anatomically distinct modules in the brain.