1. Neuroscience

A quadratic model captures the human V1 response to variations in chromatic direction and contrast

  1. Michael A Barnett  Is a corresponding author
  2. Geoffrey K Aguirre
  3. David Brainard
  1. University of Pennsylvania, United States
https://doi.org/10.7554/eLife.65590
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  1. Michael A Barnett
  2. Geoffrey K Aguirre
  3. David Brainard
(2021)
A quadratic model captures the human V1 response to variations in chromatic direction and contrast
eLife 10:e65590.
https://doi.org/10.7554/eLife.65590
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Abstract

An important goal for vision science is to develop quantitative models of the representation of visual signals at post-receptoral sites. To this end, we develop the quadratic color model (QCM) and examine its ability to account for the BOLD fMRI response in human V1 to spatially-uniform, temporal chromatic modulations that systematically vary in chromatic direction and contrast. We find that the QCM explains the same, cross-validated variance as a conventional general linear model, with far fewer free parameters. The QCM generalizes to allow prediction of V1 responses to a large range of modulations. We replicate the results for each subject and find good agreement across both replications and subjects. We find that within the LM cone contrast plane, V1 is most sensitive to L-M contrast modulations and least sensitive to L+M contrast modulations. Within V1, we observe little to no change in chromatic sensitivity as a function of eccentricity.

Data availability

The raw fMRI data from our experiment have been deposited to OpenNeuro, under the doi:10.18112/openneuro.ds003752.v1.0.0.

The following data sets were generated

Article and author information

Author details

  1. Michael A Barnett

    Department of Psychology, University of Pennsylvania, Philadelphia, United States
    For correspondence
    micalan@sas.upenn.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-8355-4601

  2. Geoffrey K Aguirre

    Neurology, University of Pennsylvania, Philadelphia, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-4028-3100

  3. David Brainard

    Neurology, University of Pennsylvania, Philadelphia, United States
    Competing interests
    The authors declare that no competing interests exist.

Funding

National Science Foundation (DGE-1845298)

  • Michael A Barnett

National Institutes of Health (RO1 EY10016)

  • David Brainard

National Institutes of Health (Core GrantP30 EY001583)

  • David Brainard

The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.

Ethics

Human subjects: The research was approved by the University of Pennsylvania Institutional Review Board (Protocol: Photoreceptor directed light modulation 817774). All subjects gave informed written consent and were financially compensated for their participation.

Copyright

© 2021, Barnett 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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  1. Michael A Barnett
  2. Geoffrey K Aguirre
  3. David Brainard
(2021)
A quadratic model captures the human V1 response to variations in chromatic direction and contrast
eLife 10:e65590.
https://doi.org/10.7554/eLife.65590

Share this article

https://doi.org/10.7554/eLife.65590

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