The role of perirhinal cortex in visual discrimination learning for visual secondary reinforcement in rats

Eacott, M.J., Norman, G. and Gaffan, E.A. (2003) The role of perirhinal cortex in visual discrimination learning for visual secondary reinforcement in rats. Behavioral Neuroscience, 117 (6). pp. 1318-1325. ISSN 0735-7044 doi: 10.1037/0735-7044.117.6.1318

Abstract/Summary

Perirhinal cortex in monkeys has been thought to be involved in visual associative learning. The authors examined rats' ability to make associations between visual stimuli in a visual secondary reinforcement task. Rats learned 2-choice visual discriminations for secondary visual reinforcement. They showed significant learning of discriminations before any primary reinforcement. Following bilateral perirhinal cortex lesions, rats continued to learn visual discriminations for visual secondary reinforcement at the same rate as before surgery. Thus, this study does not support a critical role of perirhinal cortex in learning for visual secondary reinforcement. Contrasting this result with other positive results, the authors suggest that the role of perirhinal cortex is in "within-object" associations and that it plays a much lesser role in stimulus-stimulus associations between objects.