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The large-scale organization of shape processing in the ventral and dorsal pathways

  1. Erez Freud  Is a corresponding author
  2. Jody C Culham
  3. David C Plaut
  4. Marlene Behrmann
  1. Carnegie Mellon University, United States
  2. University of Western Ontario, Canada
Research Article
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Cite this article as: eLife 2017;6:e27576 doi: 10.7554/eLife.27576

Abstract

Although shape perception is considered a function of the ventral visual pathway, evidence suggests that the dorsal pathway also derives shape-based representations. In two psychophysics and neuroimaging experiments, we characterized the response properties, topographical organization and perceptual relevance of these representations. In both pathways, shape sensitivity increased from early visual cortex to extrastriate cortex but then decreased in anterior regions. Moreover, the lateral aspect of the ventral pathway and posterior regions of the dorsal pathway were sensitive to the availability of fundamental shape properties, even for unrecognizable images. This apparent representational similarity between the posterior-dorsal and lateral-ventral regions was corroborated by a multivariate analysis. Finally, as with ventral pathway, the activation profile of posterior dorsal regions was correlated with recognition performance, suggesting a possible contribution to perception. These findings challenge a strict functional dichotomy between the pathways and suggest a more distributed model of shape processing.

Article and author information

Author details

  1. Erez Freud

    Department of Psychology, Carnegie Mellon University, Pittsburgh, United States
    For correspondence
    erezfreud@gmail.com
    Competing interests
    No competing interests declared.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-3758-3855

  2. Jody C Culham

    The Brain and Mind Institute, University of Western Ontario, London, Canada
    Competing interests
    Jody C Culham, Reviewing editor, eLife.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-0754-2999

  3. David C Plaut

    Department of Psychology, Carnegie Mellon University, Pittsburgh, United States
    Competing interests
    No competing interests declared.

  4. Marlene Behrmann

    Department of Psychology, Carnegie Mellon University, Pittsburgh, United States
    Competing interests
    No competing interests declared.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-3814-1015

Funding

Israel Science Foundation (grant No. 65/15)

  • Erez Freud

Yad Hanadiv Postdoctoral Fellowship

  • Erez Freud

National Science Foundation (BCS-1354350)

  • David C Plaut
  • Marlene Behrmann

Pennsylvania Department of Health (Commonwealth Universal Research Enhancement Program)

  • David C Plaut

Canadian Institutes of Health Research (MOP 130345)

  • Jody C Culham

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

Ethics

Human subjects: As detailed in the manuscript, all subjects had normal or corrected-to-normal vision and were financially compensated for their participation. Informed consent and consent to publish was obtained in accordance with ethical standards set out by the Declaration of Helsinki (1964) and with procedures approved by the IRB committee of Carnegie Mellon University.

Reviewing Editor

  1. Nicholas Turk-Browne, Princeton University, United States

Publication history

  1. Received: April 7, 2017
  2. Accepted: September 29, 2017
  3. Accepted Manuscript published: October 5, 2017 (version 1)
  4. Version of Record published: October 27, 2017 (version 2)
  5. Version of Record updated: December 20, 2017 (version 3)

Copyright

© 2017, Freud 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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