Bidirectional encoding of motion contrast in the mouse superior colliculus

  1. Jad Barchini
  2. Xuefeng Shi
  3. Hui Chen
  4. Jianhua Cang  Is a corresponding author
  1. Northwestern University, United States

Abstract

Detection of salient objects in the visual scene is a vital aspect of an animal's interactions with its environment. Here, we show that neurons in the mouse superior colliculus (SC) encode visual saliency by detecting motion contrast between stimulus center and surround. Excitatory neurons in the most superficial lamina of the SC are contextually modulated, monotonically increasing their response from suppression by the same-direction surround to maximal potentiation by an oppositely-moving surround. The degree of this potentiation declines with depth in the SC. Inhibitory neurons are suppressed by any surround at all depths. These response modulations in both neuronal populations are much more prominent to direction contrast than to phase, temporal frequency, or static orientation contrast, suggesting feature-specific saliency encoding in the mouse SC. Together, our findings provide evidence supporting locally generated feature representations in the SC, and lay the foundations towards a mechanistic and evolutionary understanding of their emergence.

Data availability

Source data files have been provided for Figures 1-7.

Article and author information

Author details

  1. Jad Barchini

    Department of Neurobiology, Northwestern University, Evanston, United States
    Competing interests
    The authors declare that no competing interests exist.
  2. Xuefeng Shi

    Department of Neurobiology, Northwestern University, Evanston, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. Hui Chen

    Department of Neurobiology, Northwestern University, Evanston, United States
    Competing interests
    The authors declare that no competing interests exist.
  4. Jianhua Cang

    Department of Neurobiology, Northwestern University, Evanston, United States
    For correspondence
    cang@virginia.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-0760-7468

Funding

National Institutes of Health (R01EY020950)

  • Jianhua Cang

National Institutes of Health (R01EY026286)

  • Jianhua Cang

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

Reviewing Editor

  1. Fred Rieke, University of Washington, United States

Ethics

Animal experimentation: All experimental procedures were approved by the Northwestern University Institutional Animal Care and Use Committee, protocol #IS00001946.

Version history

  1. Received: January 20, 2018
  2. Accepted: July 1, 2018
  3. Accepted Manuscript published: July 2, 2018 (version 1)
  4. Version of Record published: July 17, 2018 (version 2)

Copyright

© 2018, Barchini 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. Jad Barchini
  2. Xuefeng Shi
  3. Hui Chen
  4. Jianhua Cang
(2018)
Bidirectional encoding of motion contrast in the mouse superior colliculus
eLife 7:e35261.
https://doi.org/10.7554/eLife.35261

Share this article

https://doi.org/10.7554/eLife.35261

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