Gain, not concomitant changes in spatial receptive field properties, improves task performance in a neural network attention model
Attention allows us to focus sensory processing on behaviorally relevant aspects of the visual world. One potential mechanism of attention is a change in the gain of sensory responses. However, changing gain at early stages could have multiple downstream consequences for visual processing. Which, if any, of these effects can account for the benefits of attention for detection and discrimination? Using a model of primate visual cortex we document how a Gaussian-shaped gain modulation results in changes to spatial tuning properties. Forcing the model to use only these changes failed to produce any benefit in task performance. Instead, we found that gain alone was both necessary and sufficient to explain category detection and discrimination during attention. Our results show how gain can give rise to changes in receptive fields which are not necessary for enhancing task performance.
The images and composite grids used in this study as well as the code necessary to replicate our analyses are available in the Open Science Framework with the identifier 10.17605/OSF.IO/AGHQK.
Article and author information
Washington Ressearch Foundation (Postdoctoral Fellowship)
- Daniel Birman
Research to Prevent Blindness
- Justin L Gardner
Lions Club International
- Justin L Gardner
Hellman Fellows Fund
- Justin L Gardner
National Eye Institute (T32EY07031)
- Daniel Birman
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Human subjects: Procedures were approved in advance by the Stanford Institutional Review Board on human participants research and all observers gave prior written informed consent before participating (Protocol IRB-32120).
- John T Serences, University of California, San Diego, United States
- Received: March 5, 2022
- Accepted: May 12, 2023
- Accepted Manuscript published: May 15, 2023 (version 1)
© 2023, Fox 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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