Learning place cells, grid cells and invariances with excitatory and inhibitory plasticity
Abstract
Neurons in the hippocampus and adjacent brain areas show a large diversity in their tuning to location and head direction. The underlying circuit mechanisms are not resolved. In particular, it is unclear why certain cell types are selective to one spatial variable, but invariant to another. For example, place cells are typically invariant to head direction. We propose that all observed spatial tuning patterns - in both their selectivity and their invariance - arise from the same mechanism: Excitatory and inhibitory synaptic plasticity that is driven by the spatial tuning statistics of synaptic inputs. Using simulations and a mathematical analysis, we show that combined excitatory and inhibitory plasticity can lead to localized, grid-like or invariant activity. Combinations of different input statistics along different spatial dimensions reproduce all major spatial tuning patterns observed in rodents. The model is robust to changes in parameters, develops patterns on behavioral timescales and makes distinctive experimental predictions.
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Author details
Funding
German Federal Ministry for Education and Research (FKZ 01GQ1201)
- Henning Sprekeler
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- David Foster, University of California, Berkeley, United States
Version history
- Received: December 21, 2017
- Accepted: February 19, 2018
- Accepted Manuscript published: February 21, 2018 (version 1)
- Version of Record published: April 30, 2018 (version 2)
Copyright
© 2018, Weber & Sprekeler
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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