A visual sense of number emerges from divisive normalization in a simple center-surround convolutional network
- University of Massachusetts Amherst, United States
Abstract
Many species of animals exhibit an intuitive sense of number, suggesting a fundamental neural mechanism for representing numerosity in a visual scene. Recent empirical studies demonstrate that early feedforward visual responses are sensitive to numerosity of a dot array but substantially less so to continuous dimensions orthogonal to numerosity, such as size and spacing of the dots. However, the mechanisms that extract numerosity are unknown. Here we identified the core neurocomputational principles underlying these effects: (1) center-surround contrast filters; (2) at different spatial scales; with (3) divisive normalization across network units. In an untrained computational model, these principles eliminated sensitivity to size and spacing, making numerosity the main determinant of the neuronal response magnitude. Moreover, a model implementation of these principles explained both well-known and relatively novel illusions of numerosity perception across space and time. This supports the conclusion that the neural structures and feedforward processes that encode numerosity naturally produce visual illusions of numerosity. Together, these results identify a set of neurocomputational properties that gives rise to the ubiquity of the number sense in the animal kingdom.
Data availability
The current manuscript is a computational study, so no data have been generated for this manuscript. Modelling code is uploaded in the following public repository: https://osf.io/4rwjs/.
Article and author information
Author details
Funding
National Science Foundation (BCS 1654089)
- Joonkoo Park
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- John T Serences, University of California, San Diego, United States
Version history
- Preprint posted: June 1, 2022 (view preprint)
- Received: June 11, 2022
- Accepted: October 2, 2022
- Accepted Manuscript published: October 3, 2022 (version 1)
- Version of Record published: October 19, 2022 (version 2)
Copyright
© 2022, Park & Huber
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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A visual sense of number emerges from divisive normalization in a simple center-surround convolutional network
eLife 11:e80990.
https://doi.org/10.7554/eLife.80990
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