An alternative explanation for reported integration and competition between space and time in the hippocampus

Szmidt, F.; Mininni, C. J.

doi:10.1101/2025.03.10.642114

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bioRxiv · 10.1101/2025.03.10.642114

An alternative explanation for reported integration and competition between space and time in the hippocampus

Szmidt, F.·Mininni, C. J.

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Abstract

Hippocampal place and time cells are thought to be part of the brains spatial and temporal representation. In the article "Integration and competition between space and time in the hippocampus", Chen et al. showed that hippocampal neurons with mixed selectivity for space and time shift their firing fields depending on the animals speed. Here, we reproduce this phenomenon with a simple continuous line attractor that only integrates the animals velocity. Since our model has no genuine time-encoding capabilities, it constitutes an alternative explanation for Chen et al. findings and challenges the claim that the observed firing field shifts are sufficient evidence for a competitive and integrated representation of space-time, as the authors suggested.

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Szmidt, F., Mininni, C. J.. 2025-03-11. An alternative explanation for reported integration and competition between space and time in the hippocampus. https://doi.org/10.1101/2025.03.10.642114

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