Abstract
Posterior parietal cortex (PPC) has been involved in controlling body movement and navigation, and in making decisions based on vision. To evaluate these views, we measured PPC activity while mice performed a visual decision task by virtual navigation. We discovered that PPC neurons are selective for specific combinations of the animal’s position in the environment and of its heading angle. This selectivity closely predicted the activity of PPC cells, including their apparent selectivity for the mouse’s decision and the arrangement of their firing patterns in sequences, both of which simply reflected the influence on PPC of the animal’s navigation trajectory. Alternative models based on visual or motor variables were not as successful. We conclude that when mice use vision to make spatial choices, parietal cortex encodes navigational attributes such as position and heading rather than decisions.