The Anatomy of Context.

For most of my career, I focused on understanding how and where spatial context, the place where things happen, is represented in the brain. My interest in this began in the early 1990's, during my postdoctoral training with David Amaral, when we defined the rodent homolog of the primate parahippocampal cortex, a region implicated in processing spatial and contextual information. We parceled out the caudal portion of the rat perirhinal cortex (PER) and called it the postrhinal cortex (POR). In my own lab at Brown University, I continued to study the anatomy of the PER, POR, and entorhinal cortices. I also began to characterize and differentiate the functions of these regions, particularly the newly defined POR and the redefined PER. Our electrophysiological and behavioral evidence supports a view of POR function that aligns with our anatomical evidence. Briefly, the POR integrates object and feature information from the PER with spatial information from the retrosplenial, posterior parietal, and secondary visual cortices and the pulvinar and uses this information to represent specific environmental contexts, including the spatial arrangement of objects and features within each context. In addition to maintaining a representation of the current context, the POR plays an attentional role by continually monitoring the context for changes and updating the context representation when changes occur. This context representation is accessible to other regions for cognitive processes, including binding life events with context to form episodic memories, guiding context-relevant behavior, and recognizing objects within scenes and contexts.