Posterior parietal cortex maps progress along routes sharing the same meta-structure

Neurons of posterior parietal cortex were recorded as rats performed a working memory task within a network of intersecting paths. The specific routes utilized in task performance provided opportunity to contrast responses of posterior parietal cortex sub-populations to linear and angular velocity with more complex responses that map route progress. We found evidence for the presence of posterior parietal cortex neurons that generalize in their firing patterns across routes having the same shape but opposite action series. The results indicate that posterior parietal cortex has the capacity to generalize the mapping of route progress independent of the specific actions taken to move through those routes. We suggest that such encoding can form the basis for learning the meta-structural organization of a non-random path network structure, such as that commonly found in cities.