Framing of grid cells within and beyond navigation boundaries

  1. Francesco Savelli  Is a corresponding author
  2. JD Luck
  3. James J Knierim  Is a corresponding author
  1. Johns Hopkins University, United States

Abstract

Grid cells represent an ideal candidate to investigate the allocentric determinants of the brain's cognitive map. Most studies of grid cells emphasized the roles of geometric boundaries within the navigational range of the animal. Behaviors such as novel route-taking between local environments indicate the presence of additional inputs from remote cues beyond the navigational borders. To investigate these influences, we recorded grid cells as rats explored an open-field platform in a room with salient, remote cues. The platform was rotated or translated relative to the room frame of reference. Although the local, geometric frame of reference often exerted the strongest control over the grids, the remote cues demonstrated a consistent, sometimes dominant, countervailing influence. Thus, grid cells are controlled by both local geometric boundaries and remote spatial cues, consistent with prior studies of hippocampal place cells and providing a rich representational repertoire to support complex navigational (and perhaps mnemonic) processes.

Article and author information

Author details

  1. Francesco Savelli

    Zanvyl Krieger Mind/Brain Institute, Johns Hopkins University, Baltimore, United States
    For correspondence
    fsavelli@jhu.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-8588-0865
  2. JD Luck

    Zanvyl Krieger Mind/Brain Institute, Johns Hopkins University, Baltimore, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. James J Knierim

    Zanvyl Krieger Mind/Brain Institute, Johns Hopkins University, Baltimore, United States
    For correspondence
    jknierim@jhu.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-1796-2930

Funding

National Institute of Neurological Disorders and Stroke (R01 NS039456)

  • James J Knierim

Human Frontier Science Program (LT00683/2006-C)

  • Francesco Savelli

National Institute of Mental Health (R01 MH079511)

  • James J Knierim

The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.

Ethics

Animal experimentation: All animal care and housing procedures followed the recommendations in the Guide for the Care and Use of Laboratory Animals of the National Institutes of Health and protocols approved by the Institutional Animal Care and Use Committee at Johns Hopkins University (Protocols RA08A540 and RA11A486).

Reviewing Editor

  1. Upinder S Bhalla, National Centre for Biological Sciences, India

Publication history

  1. Received: September 7, 2016
  2. Accepted: January 11, 2017
  3. Accepted Manuscript published: January 13, 2017 (version 1)
  4. Version of Record published: January 27, 2017 (version 2)

Copyright

© 2017, Savelli 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. Francesco Savelli
  2. JD Luck
  3. James J Knierim
(2017)
Framing of grid cells within and beyond navigation boundaries
eLife 6:e21354.
https://doi.org/10.7554/eLife.21354

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