A new no-report paradigm reveals that face cells encode both consciously perceived and suppressed stimuli

  1. Janis Karan Hesse  Is a corresponding author
  2. Doris Y Tsao  Is a corresponding author
  1. California Institute of Technology, United States

Abstract

A powerful paradigm to identify neural correlates of consciousness is binocular rivalry, wherein a constant visual stimulus evokes a varying conscious percept. It has recently been suggested that activity modulations observed during rivalry may represent the act of report rather than the conscious percept itself. Here, we performed single-unit recordings from face patches in macaque inferotemporal (IT) cortex using a no-report paradigm in which the animal's conscious percept was inferred from eye movements. We found that high proportions of IT neurons represented the conscious percept even without active report. Furthermore, on single trials we could decode both the conscious percept and the suppressed stimulus. Together, these findings indicate that (1) IT cortex possesses a true neural correlate of consciousness, and (2) this correlate consists of a population code wherein single cells multiplex representation of the conscious percept and veridical physical stimulus, rather than a subset of cells perfectly reflecting consciousness.

Data availability

All data generated or analysed during this study are included in the manuscript and supporting files.

Article and author information

Author details

  1. Janis Karan Hesse

    Biology, California Institute of Technology, Pasadena, United States
    For correspondence
    jhesse@caltech.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-0405-8632
  2. Doris Y Tsao

    Biology and Biological Engineering, California Institute of Technology, Pasadena, United States
    For correspondence
    dortsao@caltech.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-1083-1919

Funding

Howard Hughes Medical Institute

  • Doris Y Tsao

Simons Foundation

  • Doris Y Tsao

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

Ethics

Animal experimentation: All animal procedures in this study complied with local and National Institute of Health guidelines including the US National Institutes of Health Guide for Care and Use of Laboratory Animals. All experiments were performed with the approval of the Caltech Institutional Animal Care and Use Committee (IACUC), under protocol #1574.

Human subjects: The behavioral experiment with human subjects for the human psychophysics experiment complied with a protocol approved by the Caltech Institutional Review Board (IRB 19-0903). Informed consent was obtained from all subjects.

Reviewing Editor

  1. Ming Meng, South China Normal University, China

Publication history

  1. Received: April 28, 2020
  2. Accepted: November 9, 2020
  3. Accepted Manuscript published: November 11, 2020 (version 1)
  4. Version of Record published: November 19, 2020 (version 2)

Copyright

© 2020, Hesse & Tsao

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. Janis Karan Hesse
  2. Doris Y Tsao
(2020)
A new no-report paradigm reveals that face cells encode both consciously perceived and suppressed stimuli
eLife 9:e58360.
https://doi.org/10.7554/eLife.58360
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