Distinct cortical codes and temporal dynamics for conscious and unconscious percepts

  1. Moti Salti  Is a corresponding author
  2. Simo Monto
  3. Lucie Charles
  4. Jean-Remi King
  5. Lauri Parkkonen
  6. Stanislas Dehaene
  1. Institut national de la santé et de la recherche médicale, France

Abstract

The neural correlates of consciousness are typically sought by comparing the overall brain responses to perceived and unperceived stimuli. However, this comparison may be contaminated by non-specific attention, alerting, performance and reporting confounds. Here, we pursue a novel approach, tracking the neuronal coding of consciously and unconsciously perceived contents while keeping behavior identical (blindsight). EEG and MEG were recorded while participants reported the spatial location and visibility of a briefly presented target. Multivariate pattern analysis demonstrated that considerable information about spatial location traverses the cortex on blindsight trials, but that starting ≈270ms post-onset, information unique to consciously perceived stimuli emerges in superior-parietal and superior-frontal regions. Conscious access appears characterized by the entry of the perceived stimulus into a series of additional brain processes, each restricted in time, while the failure of conscious access results in the breaking of this chain and a subsequent slow decay of the lingering unconscious activity.

Article and author information

Author details

  1. Moti Salti

    Cognitive Neuroimaging Unit, Institut national de la santé et de la recherche médicale, Gif sur Yvette, France
    For correspondence
    motisalti@gmail.com
    Competing interests
    The authors declare that no competing interests exist.
  2. Simo Monto

    Cognitive Neuroimaging Unit, Institut national de la santé et de la recherche médicale, Gif sur Yvette, France
    Competing interests
    The authors declare that no competing interests exist.
  3. Lucie Charles

    Cognitive Neuroimaging Unit, Institut national de la santé et de la recherche médicale, Gif sur Yvette, France
    Competing interests
    The authors declare that no competing interests exist.
  4. Jean-Remi King

    Cognitive Neuroimaging Unit, Institut national de la santé et de la recherche médicale, Gif sur Yvette, France
    Competing interests
    The authors declare that no competing interests exist.
  5. Lauri Parkkonen

    Cognitive Neuroimaging Unit, Institut national de la santé et de la recherche médicale, Gif sur Yvette, France
    Competing interests
    The authors declare that no competing interests exist.
  6. Stanislas Dehaene

    Cognitive Neuroimaging Unit, Institut national de la santé et de la recherche médicale, Gif sur Yvette, France
    Competing interests
    The authors declare that no competing interests exist.

Reviewing Editor

  1. Heidi Johansen-Berg, University of Oxford, United Kingdom

Ethics

Human subjects: The study was approved by the by CPP IDF under the reference CPP 08 021. All subjects gave written informed consent and consent to publish before participating in the study.

Version history

  1. Received: December 8, 2014
  2. Accepted: May 20, 2015
  3. Accepted Manuscript published: May 21, 2015 (version 1)
  4. Version of Record published: June 15, 2015 (version 2)

Copyright

© 2015, Salti 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. Moti Salti
  2. Simo Monto
  3. Lucie Charles
  4. Jean-Remi King
  5. Lauri Parkkonen
  6. Stanislas Dehaene
(2015)
Distinct cortical codes and temporal dynamics for conscious and unconscious percepts
eLife 4:e05652.
https://doi.org/10.7554/eLife.05652

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https://doi.org/10.7554/eLife.05652

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