Spatial Egocentric

The hippocampus has previously been implicated in the encoding of spatial memories on a neuronal level. This encoding is accomplished through modulating firing of CA1 pyramidal cells in response to different actions performed in the same egocentric and allocentric space. In this experiment we aimed to determine the different type of CA1 cell firing rate modulation in response to movement through 2 different trajectories existing on the same track. We specifically focused on the area on our Plus-track where these two trajectories overlapped. We recorded single cells from rats and found place cells with fields on the overlapping portion of the track. About half of these cells did not show a significant change in the firing of their place field when the two trajectories were compared. However, we did find that the other half modulated their firing in three ways. First, the place field changed in magnitude of firing between the two routes. Second, the place field’s center of mass shifted depending on the route. Lastly, we found that a small percentage exhibited both forms of encoding. Our results suggest that hippocampal place cells are capable of a highly specific level of modulation affected by more then the specific location, and grand changes in direction/behavior. According to our results, these cells can distinguish between at least