A visual sense of number emerges from divisive normalization in a simple center-surround convolutional network

  1. Joonkoo Park  Is a corresponding author
  2. David E Huber
  1. 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

  1. Joonkoo Park

    Department of Psychological and Brain Sciences, University of Massachusetts Amherst, Amherst, United States
    For correspondence
    joonkoo@umass.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-6703-3961
  2. David E Huber

    Department of Psychological and Brain Sciences, University of Massachusetts Amherst, Amherst, United States
    Competing interests
    The authors declare that no competing interests exist.

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.

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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  1. Joonkoo Park
  2. David E Huber
(2022)
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

Share this article

https://doi.org/10.7554/eLife.80990

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