Session: 2

PS2-16 | Place cells activity correlates with the memory expressed in an unrewarded contextual memory task

Azul Silva


Place cells (PC) are hippocampal neurons that are tuned to spatial location and are able to change their tuning when sensory inputs change (remapping). Collectively, they are thought to form the neural basis of a cognitive map and provide the spatial dimension of episodic memory. Moreover, it has been suggested that the hippocampal ability of storing and distinguishing between different situations and contexts can be related with PC’s remapping.
Several studies have shown how PC can either remap or not as a consequence of changes in the environment. However, it is still unclear the role that PC have in episodic memory. The aim of this project is to understand how the PC activity of CA1 and CA3, two hippocampal regions, correlates with the evocation of contextual memories. To tackle this question we performed electrophysiological recordings in CA3 and CA1 while the animal was performing a task that allows us to discriminate if it recognizes a context as new, or as one it already knows. We found a significant correlation between CA3 PC activity and the memory that the animal is recalling. In particular the amount of remapping and the spatial correlation of PC activity between contexts is related with the animal’s behavioral output. These results suggest that PC activity not only is important for spatial navigation but also for evocation of contextual memories.