Framing of grid cells within and beyond navigation boundaries
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
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).
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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