Reconceiving the hippocampal map as a topological template

Abstract
Article and author information
Metrics

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

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.
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.
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

Copyright

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.