Dissecting the neural components of the hippocampal cognitive map (360G-Wellcome-203020_Z_16_Z)

The existence of place, directional, boundary and grid cells in the rat hippocampal formation provides strong evidence that this part of the brain functions as a cognitive map. This theory suggests that the hippocampal formation contains map -like representations of familiar environments which enable the animal to identify its current location together with desirable and undesirable locations and to generate the vectors to move towards or away from these. I propose to use novel behavioural tasks, high-density extracellular recording probes, 2-photon imaging, and pharmacological and optogenetic manipulation of cell activity to explore in-depth the properties of these spatial cells and the role of different components of the hippocampal formation in spatial memory and navigation. Specifically I will address the following questions: How well does the activity of place, head direction and grid cells correlate with the animal’s perception of the different aspects of space and which cells are important in supporting navigation to an unmarked goal? What are the relative roles of external landmarks versus internal path integration signals in determining the firing of place cells? Do the l grid cells signal distance travelled in a particular direction or something else such as the shape of the environment?