Cortical magnification eliminates differences in contrast sensitivity across but not around the visual field

  1. Michael Jigo
  2. Daniel Tavdy
  3. Marc Himmelberg
  4. Marisa Carrasco  Is a corresponding author
  1. New York University, United States

Abstract

Human visual performance changes dramatically both across (eccentricity) and around (polar angle) the visual field. Performance is better at the fovea, decreases with eccentricity, and is better along the horizontal than vertical meridian and along the lower than the upper vertical meridian. However, all neurophysiological and virtually all behavioral studies of cortical magnification have investigated eccentricity effects without considering polar angle. Most performance differences due to eccentricity are eliminated when stimulus size is cortically magnified (M-scaled) to equate the size of its cortical representation in primary visual cortex (V1). But does cortical magnification underlie performance differences around the visual field? Here, to assess contrast sensitivity, human adult observers performed an orientation discrimination task with constant stimulus size at different locations as well as when stimulus size was M-scaled according to stimulus eccentricity and polar angle location. We found that although M-scaling stimulus size eliminates differences across eccentricity, it does not eliminate differences around the polar angle. This finding indicates that limits in contrast sensitivity across eccentricity and around the visual field are mediated by different anatomical and computational constraints.

Data availability

Data and code pertaining to the experiment are available on the OSF repository (https://osf.io/gvkdh/; Jigo et al., 2023)

The following data sets were generated

Article and author information

Author details

  1. Michael Jigo

    Department of Psychology, New York University, New York City, United States
    Competing interests
    No competing interests declared.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-9742-4576
  2. Daniel Tavdy

    Department of Psychology, New York University, New York City, United States
    Competing interests
    No competing interests declared.
  3. Marc Himmelberg

    Department of Psychology, New York University, New York, United States
    Competing interests
    No competing interests declared.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-9133-7984
  4. Marisa Carrasco

    Department of Psychology, New York University, New York, United States
    For correspondence
    marisa.carrasco@nyu.edu
    Competing interests
    Marisa Carrasco, Reviewing editor, eLife.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-1002-9056

Funding

National Eye Institute (R01-EY027401)

  • Marisa Carrasco

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

Reviewing Editor

  1. Ming Meng, South China Normal University, China

Ethics

Human subjects: All observers provided written informed consent under the University Committee's protocol on Activities Involving Human Subjects at New York University agreeing to participate in the study and the public release of their data. All experimental procedures were approved by the Ethics Committee at the NYU Department of Psychology (IRB: FY2016-466) and were in agreement with the Declaration of Helsinki.

Version history

  1. Preprint posted: April 28, 2022 (view preprint)
  2. Received: October 14, 2022
  3. Accepted: March 16, 2023
  4. Accepted Manuscript published: March 24, 2023 (version 1)
  5. Version of Record published: April 11, 2023 (version 2)

Copyright

© 2023, Jigo 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 Jigo
  2. Daniel Tavdy
  3. Marc Himmelberg
  4. Marisa Carrasco
(2023)
Cortical magnification eliminates differences in contrast sensitivity across but not around the visual field
eLife 12:e84205.
https://doi.org/10.7554/eLife.84205

Share this article

https://doi.org/10.7554/eLife.84205

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