The amygdala and perirhinal cortex sometimes cooperate but often compete during information processing in rats, cats, and people.

The amygdala is a medial temporal lobe (MTL) structure that processes emotionally significant information. It is strongly interconnected with other MTL regions, including the perirhinal cortex (PRh) which is a site of convergence for different types of sensory information, e.g., auditory, visual, olfactory, gustatory and tactile. The amygdala and PRh have been shown to cooperate when processing emotional and sensory information via the amygdala modulating or facilitating sensory processing in the PRh. However, the two regions have also been shown to compete during some types of tasks, raising questions about the nature of their interaction. This paper reviews theories of amygdala and perirhinal cortex function derived from studies in monkeys, cats and rats. It also reviews findings from a sensory preconditioning protocol which has been used to study how these regions encode and integrate different types of information in rats, and a selection of neuroimaging studies that have produced analogous results in people. It concludes with a perspective on amygdala-rhinal interactions that addresses how and why the amygdala and PRh sometimes cooperate and often compete when processing different types of information.