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bioRxiv · 10.1101/676593

Hippocampal Neuron Functional Phenotype Influences the Stability of Its Neural Code

Abstract

Trajectory-dependent splitter neurons in the hippocampus encode information about a rodents prior trajectory during performance of a continuous alternation task. As such, they provide valuable information for supporting memory-guided behavior. Here, we employed single-photon calcium imaging in freely moving mice to investigate the emergence and fate of trajectory-dependent activity through learning and mastery of a continuous spatial alternation task. We found that the quality of trajectory-dependent information in hippocampal neurons correlated with task performance. We thus hypothesized that, due to their utility, splitter neurons would exhibit heightened stability. We found that splitter neurons were more likely to remain active and retained more consistent spatial information across multiple days than did place cells. Furthermore, we found that both splitter neurons and place cells emerged rapidly and maintained stable trajectory-dependent/spatial activity thereafter. Our results suggest that neurons with useful functional coding properties exhibit heightened stability to support memory guided behavior.

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BibTeXRIS

Kinsky, N. R., Mau, W., Sullivan, D. W., Levy, S. J., Ruesch, E. A., Hasselmo, M. E.. 2019-06-20. Hippocampal Neuron Functional Phenotype Influences the Stability of Its Neural Code. https://doi.org/10.1101/676593

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