Research goals of the group "Neural bases of spatial cognition"
Our research takes a multidisciplinary approach to the problem of how animals process spatial information to navigate in space. Recent progress on the neurophysiological bases of spatial knowledge provides support for biologically realistic computational models inspired by the concepts of cognitive psychology. Accordingly, we study not only how animals perceive and navigate in space but also the involvement of several neural systems in these abilities.
Emphasis is put on the role of the hippocampus and several neocortical areas (entorhinal, prefrontal, parietal, ...) thought to subserve distinct functions in spatial processing and spatial navigation. Lesion studies are aimed at describing the differential effects induced by damage of each area. Reversible inactivation studies allow us to address the specific phase of information processing for each system.
Our first studies of unit activity in freely moving rats have demonstrated the existence of "place cells" in the ventral hippocampus. We showed that the control of dorsal hippocampal place cell firing is exerted by selective classes of spatial information stemming from the distal environment. We also demonstrated that blind rats have place cells very similar to normal rats. We have studied the coupling between the spatial firing of place cells and navigation performance to establish that place cells participate in an important way in the calculation of paths.
Our future research is based on the assumption that spatial navigation depends on interactions between the hippocampus and neocortical structures. These interactions will be investigated by recording single-unit activity simultaneously from several areas. We also shall continue to develop original behavioral paradigms designed to show how space is represented in animals, with the goal of building biologically realistic models based on behavioral and brain data. Broadly speaking, our work will focus on (1) the neural bases of spatial cognition, (2) the properties of spatial representations in animals, (3) the neural substrates of goal-directed behaviors.