Place-cell capacity and volatility with grid-like inputs
Abstract
What factors constrain the arrangement of the multiple fields of a place cell? By modeling place cells as perceptrons that act on multiscale periodic grid-cell inputs, we analytically enumerate a place cell's repertoire - how many field arrangements it can realize without external cues while its grid inputs are unique; and derive its capacity - the spatial range over which it can achieve any field arrangement. We show that the repertoire is very large and relatively noise-robust. However, the repertoire is a vanishing fraction of all arrangements, while capacity scales only as the sum of the grid periods so field arrangements are constrained over larger distances. Thus, grid-driven place field arrangements define a large response scaffold that is strongly constrained by its structured inputs. Finally, we show that altering grid-place weights to generate an arbitrary new place field strongly affects existing arrangements, which could explain the volatility of the place code.
Data availability
The authors confirm that the data supporting the findings of this study are available within the article. Implementation details and code are available at: https://github.com/myyim/placecellperceptron.
Article and author information
Author details
Funding
Simons Foundation (Simons Collaboration on the Global Brain)
- Man Yi Yim
- Ila R Fiete
Howard Hughes Medical Institute (Faculty Scholars Program)
- Ila R Fiete
Alfred P. Sloan Foundation (Alfred P. Sloan Research Fellowship FG-2017-9554)
- Thibaud Taillefumier
Office of Naval Research (S&T BAA Award N00014-19-1-2584)
- Ila R Fiete
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2021, Yim 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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