Reconceiving the hippocampal map as a topological template

  1. Yuri Dabaghian  Is a corresponding author
  2. Vicky L Brandt
  3. Loren M Frank
  1. Jan and Dan Duncan Neurological Research Institute at Texas Children's Hospital, United States
  2. University of California, San Francisco, United States

Abstract

The role of the hippocampus in spatial cognition is incontrovertible yet controversial. Place cells, initially thought to be location-specifiers, turn out to respond promiscuously to a wide range of stimuli. Here we test the idea, which we have recently shown works in a computational model, that the hippocampal place cells may ultimately be interested in a space's topological qualities (its connectivity) more than its geometry (distances and angles); such higher-order functioning would be more consistent with other known hippocampal functions. We recorded place cell activity in rats exploring morphing linear tracks that allowed us to dissociate the geometry of the track from its topology. The resulting place fields preserved the relative sequence of places visited along the track but did not vary with the metrical features of the track or the direction of the rat's movement. These results suggest a reinterpretation of previous studies and new directions for future experiments.

Article and author information

Author details

  1. Yuri Dabaghian

    Jan and Dan Duncan Neurological Research Institute at Texas Children's Hospital, Houston, United States
    For correspondence
    dabaghia@bcm.edu
    Competing interests
    The authors declare that no competing interests exist.
  2. Vicky L Brandt

    Jan and Dan Duncan Neurological Research Institute at Texas Children's Hospital, Houston, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. Loren M Frank

    University of California, San Francisco, San Francisco, United States
    Competing interests
    The authors declare that no competing interests exist.

Ethics

Animal experimentation: All the experimental procedures were approved by the Institutional Animal Care and Use Committee at UCSF, Approval Number: AN081431-03D

Reviewing Editor

  1. Howard Eichenbaum, Boston University, United States

Publication history

  1. Received: May 26, 2014
  2. Accepted: August 19, 2014
  3. Accepted Manuscript published: August 20, 2014 (version 1)
  4. Version of Record published: September 12, 2014 (version 2)

Copyright

© 2014, Dabaghian 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. Yuri Dabaghian
  2. Vicky L Brandt
  3. Loren M Frank
(2014)
Reconceiving the hippocampal map as a topological template
eLife 3:e03476.
https://doi.org/10.7554/eLife.03476

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