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bioRxiv · 10.1101/2022.09.25.509420

Hippocampo-cortical circuits for selective memory encoding, routing, and replay

Harvey, R. E.·Robinson, H. L.·Liu, C.·Oliva, A.·Fernandez-Ruiz, A.
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Abstract

Traditionally considered a homogeneous cell type, hippocampal pyramidal cells have been recently shown to be highly diverse. However, how this cellular diversity relates to the different hippocampal network computations that support memory-guided behavior is not yet known. We discovered that the anatomical identity of pyramidal cells is a major organizing principle of CA1 assembly dynamics, the emergence of memory replay, and cortical projection patterns. Segregated pyramidal cell subpopulations encoded trajectory and choice-specific information or tracked changes in reward configuration respectively, and selectively routed these representations to different cortical targets. Furthermore, distinct hippocampo-cortical assemblies coordinated the reactivation of complementary memory representations. These findings reveal the existence of specialized hippocampo-cortical subcircuits and provide a cellular mechanism that supports the computational flexibility and memory capacities of these structures.

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Harvey, R. E., Robinson, H. L., Liu, C., Oliva, A., Fernandez-Ruiz, A.. 2022-09-27. Hippocampo-cortical circuits for selective memory encoding, routing, and replay. https://doi.org/10.1101/2022.09.25.509420

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