A principle of economy predicts the functional architecture of grid cells
Grid cells in the brain respond when an animal occupies a periodic lattice of 'grid fields' during navigation. Grids are organized in modules with different periodicity. We propose that the grid system implements a hierarchical code for space that economizes the number of neurons required to encode location with a given resolution across a range equal to the largest period. This theory predicts: (i) grid fields should lie on a triangular lattice, (ii) grid scales should follow a geometric progression, (iii) the ratio between adjacent grid scales should be e^1/2 for idealized neurons, and lie between 1.4-1.7 for realistic neurons, (iv) the scale ratio should vary modestly within and between animals. These results explain the measured grid structure in rodents. We also predict optimal organization in one and three dimensions, the number of modules, and, with added assumptions, the ratio between grid periods and field widths.
Article and author information
- Frances K Skinner, University Health Network, Canada
- Received: April 27, 2015
- Accepted: September 1, 2015
- Accepted Manuscript published: September 3, 2015 (version 1)
- Version of Record published: October 23, 2015 (version 2)
© 2015, Wei 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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