Understanding large-scale spatial navigation using virtual reality, multi-site electrophysiological recordings in the hippocampus
Alla Solod – Equipe Mécanismes neuronaux de la cognition spatiale

Résumé
Animals can navigate an environment using various strategies. One of these is the ability to build an internal cognitive map of the space. Place cells in the hippocampus are believed to be the building blocks of the cognitive map and participate in encoding environmental information. In small-scale laboratory mazes, place cells usually exhibit one place field. In studies of large-scale environments, it has been shown that place cells exhibit multiscale coding with quasi-homogeneous coverage of the space. However, little is known about how place cells encode large naturalistic environments that are highly dynamic, with typically inhomogeneous distributions of cues and reward locations. Considering that various factors have been shown to modulate place cell activity in small-scale environments, it is possible that this modulation can also occur during the encoding of dynamic large-scale environments. In this study, we aimed to investigate which factors could modulate place cell coding in a large-scale environment using a semi-naturalistic virtual reality (VR) setup with various inhomogeneously distributed objects and stochastically distributed rewards that are similar to natural settings. In such a setting, we did not observe place cell type spatial encoding; instead, we found that mice could learn a general rule about the environment, abstract it from the spatial layout, and navigate the large-scale environment, likely using schema-based navigation.

Jury
Anna Montagnini, Présidente – INT, Marseille
Sylvia Wirth, Rapporteure – ISC Marc Jeannerod, Lyon
Caswell Barry, Rapporteur – UCL, Londres
Christoph Shmidt Hieber, Examinatreur – University of Jena
Jérôme Epsztein, Directeur de thèse – Inmed, Marseille
Hervé Ruault, Co-directeur de thèse – Centuri, Marseille

Mercredi 18 décembre à 14h30 – Salle de conférence de l’Inmed