EFFECT OF REWARD DISTRIBUTION AND EXTINCTION ON MOUSE BEHAVIOR AND PLACE CELL DISTRIBUTION IN AN OPEN-FIELD TASK

We investigated how reward distribution and behavioral policy shape hippocampal place cell organization and how place cell distributions may influence navigation, providing a neural basis for subjective space in mice. We recorded hippocampal CA1 activity in freely moving mice using calcium imaging while animals navigated open-field arenas containing both lateral and central reward regions. Behavioral trajectories, occupancy, and running speed were quantified, and place cell density is being analyzed across experimental conditions. We further explored how changes in reward structure influences behavioral policy by analyzing mouse trajectories during reward extinction. We observed robust behavioral effects, including increased occupancy and reduced running speed in reward regions. These effects persisted for several sessions after reward extinction before dissipating. These findings demonstrate reward-dependent distortions in navigation behavior, consistent with a subjective representation of space. We will test how these behavioral effects relate to changes in place cell density and organization.