Venue: Centre Broca
Defense in English 
Alena Spitsyn
Team Olfaction and memory
IINS
Thesis supervisor: Lisa Roux
Title
“Beyond social memories: hippocampal CA2 activity when navigating for rewards”
Abstract
Animals’ survival largely depends on their ability to learn and remember how to navigate towards sites of interest such as food locations or home. The hippocampus is a key brain structure for spatial memory. Hippocampal place cells fire at discrete locations (their place fields) as subjects move through their environment, thereby providing a neural code for current location during locomotion. However, in the CA1 region of the hippocampus, this cognitive spatial map is not homogeneous: several studies indicate that place fields tend to accumulate next to salient cues such as rewards, a process called “goal-oriented remapping”. The mechanisms underlying the establishment of this “biased” map are very little understood. Moreover, whether the often overlooked CA2 region of the hippocampus also presents such map goal-oriented bias and/or contributes to CA1 remapping is unknown.
The goal of this PhD project was to characterize the activity of the CA2 region during spatial navigation towards rewards and during reward consumption to test the hypothesis that it participates in biasing the hippocampal cognitive towards salient locations.
Keywords
memory, hippocampus, reward, spatial navigation, electrophysiology
Publication
Maïthé Loisy, Guillaume Bouisset, Sebastien Lopez, Maud Muller, Alena Spitsyn, Jeanne Duval, Rebecca Ann Piskorowski, Laure Verret, Vivien Chevaleyre (2022) Sequential inhibitory plasticities in hippocampal area CA2 and social memory formation. Neuron Vol110, I17
Jury
- Lisa ROUX
- Azahara OLIVA
- Stéphanie TROUCHE
- François GEORGES
- Rebecca Ann PISKOROWSKI
- Tristan STÖBER