Flexible coding of time or distance in hippocampal cells
- Technion - Israel Institute of Technology, Israel
- Boston University, United States
Abstract
Analysis of neuronal activity in the hippocampus of behaving animals has revealed cells acting as 'Time Cells', which exhibit selective spiking patterns at specific time intervals since a triggering event, and 'Distance Cells', which encode the traversal of specific distances. Other neurons exhibit a combination of these features, alongside place selectivity. This study aims to investigate how the task performed by animals during recording sessions influences the formation of these representations. We analyzed data from a treadmill running study conducted by Kraus et al.1 in which rats were trained to run at different velocities. The rats were recorded in two trial contexts: a 'fixed time' condition, where the animal ran on the treadmill for a predetermined duration before proceeding, and a 'fixed distance' condition, where the animal ran a specific distance on the treadmill. Our findings indicate that the type of experimental condition significantly influenced the encoding of hippocampal cells. Specifically, distance-encoding cells dominated in fixed-distance experiments, whereas time-encoding cells dominated in fixed-time experiments. These results underscore the flexible coding capabilities of the hippocampus, which are shaped by over-representation of salient variables associated with reward conditions.
Data availability
The current manuscript is a re-analysis of data collected for a previously published paper (Kraus, Benjamin J., Robert J. Robinson II, John A. White, Howard Eichenbaum, and Michael E. Hasselmo. "Hippocampal "time cells": time versus path integration." Neuron 78, no. 6 (2013): 1090-1101).Data used in this paper is available as Matlab files on Dryad:Abramson, Shai et al. (2022), Data for Time or distance: predictive coding of Hippocampal cells, Dryad, Dataset, https://doi.org/10.5061/dryad.ngf1vhhxp
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Data for Time or distance: predictive coding of Hippocampal cellsDryad Digital Repository, doi:10.5061/dryad.ngf1vhhxp.
Article and author information
Author details
Funding
Israel Science Foundation (2183/21)
- Dori Derdikman
Binational Science Foundation -NIH CRCNS (BSF:2019807 (NIH: 1R01 MH125544-01 ))
- Dori Derdikman
Prince Center for the Aging Brain
- Dori Derdikman
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2023, Abramson et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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Flexible coding of time or distance in hippocampal cells
eLife 12:e83930.
https://doi.org/10.7554/eLife.83930
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