1. Neuroscience

Flexible coding of time or distance in hippocampal cells

  1. Shai Abramson
  2. Benjamin J Kraus
  3. John A White
  4. Michael E Hasselmo
  5. Dori Derdikman  Is a corresponding author
  6. Genela Morris  Is a corresponding author
  1. Technion - Israel Institute of Technology, Israel
  2. Boston University, United States
https://doi.org/10.7554/eLife.83930
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  1. Shai Abramson
  2. Benjamin J Kraus
  3. John A White
  4. Michael E Hasselmo
  5. Dori Derdikman
  6. Genela Morris
(2023)
Flexible coding of time or distance in hippocampal cells
eLife 12:e83930.
https://doi.org/10.7554/eLife.83930
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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

The following previously published data sets were used

Article and author information

Author details

  1. Shai Abramson

    Rappaport Faculty of Medicine and Research Institute, Technion - Israel Institute of Technology, Haifa, Israel
    Competing interests
    The authors declare that no competing interests exist.

  2. Benjamin J Kraus

    Center for Memory and Brain, Boston University, Boston, United States
    Competing interests
    The authors declare that no competing interests exist.

  3. John A White

    Department of Biomedical Engineering, Boston University, Boston, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-1073-2638

  4. Michael E Hasselmo

    Center for Memory and Brain, Boston University, Boston, United States
    Competing interests
    The authors declare that no competing interests exist.

  5. Dori Derdikman

    Rappaport Faculty of Medicine and Research Institute, Technion - Israel Institute of Technology, Haifa, Israel
    For correspondence
    derdik@technion.ac.il
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-3677-6321

  6. Genela Morris

    Rappaport Faculty of Medicine and Research Institute, Technion - Israel Institute of Technology, Haifa, Israel
    For correspondence
    gmorris@sci.haifa.ac.il
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-5417-8977

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.

Reviewing Editor

  1. Laura L Colgin, University of Texas at Austin, United States

Version history

  1. Received: October 4, 2022
  2. Preprint posted: October 24, 2022 (view preprint)
  3. Accepted: October 12, 2023
  4. Accepted Manuscript published: October 16, 2023 (version 1)
  5. Version of Record published: December 11, 2023 (version 2)

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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  1. Shai Abramson
  2. Benjamin J Kraus
  3. John A White
  4. Michael E Hasselmo
  5. Dori Derdikman
  6. Genela Morris
(2023)
Flexible coding of time or distance in hippocampal cells
eLife 12:e83930.
https://doi.org/10.7554/eLife.83930

Share this article

https://doi.org/10.7554/eLife.83930

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