A theory of working memory without consciousness or sustained activity

  1. Darinka Trübutschek  Is a corresponding author
  2. Sébastien Marti
  3. Andrés Ojeda
  4. Jean-Rémi King
  5. Yuanyuan Mi
  6. Misha Tsodyks
  7. Stanislas Dehaene
  1. Ecole des Neurosciences de Paris Ile-de-France, France
  2. Université Paris-Sud, France
  3. University of Oxford, United Kingdom
  4. New York University, United States
  5. Institute of Basic Medical Sciences, China
  6. Weizmann Institute of Science, Israel
  7. Institut national de la santé et de la recherche médicale, France

Abstract

Working memory and conscious perception are thought to share similar brain mechanisms, yet recent reports of non-conscious working memory challenge this view. Combining visual masking with magnetoencephalography, we investigate the reality of non-conscious working memory and dissect its neural mechanisms. In a spatial delayed-response task, participants reported the location of a subjectively unseen target above chance-level after several seconds. Conscious perception and conscious working memory were characterized by similar signatures: a sustained desynchronization in the alpha/beta band over frontal cortex, and a decodable representation of target location in posterior sensors. During non-conscious working memory, such activity vanished. Our findings contradict models that identify working memory with sustained neural firing, but are compatible with recent proposals of ‘activity-silent’ working memory. We present a theoretical framework and simulations showing how slowly decaying synaptic changes allow cell assemblies to go dormant during the delay, yet be retrieved above chance-level after several seconds.

Article and author information

Author details

  1. Darinka Trübutschek

    Ecole des Neurosciences de Paris Ile-de-France, Paris, France
    For correspondence
    darinkat87@gmail.com
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-7977-1366
  2. Sébastien Marti

    Cognitive Neuroimaging Unit, CEA DSV/I2BM, INSERM, Université Paris-Sud, Gif-sur-Yvette, France
    Competing interests
    The authors declare that no competing interests exist.
  3. Andrés Ojeda

    Department of Zoology, University of Oxford, Oxford, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  4. Jean-Rémi King

    Department of Psychology, New York University, New York, United States
    Competing interests
    The authors declare that no competing interests exist.
  5. Yuanyuan Mi

    Brain Science Center, Institute of Basic Medical Sciences, Beijing, China
    Competing interests
    The authors declare that no competing interests exist.
  6. Misha Tsodyks

    Department of Neurobiology, Weizmann Institute of Science, Rehovot, Israel
    Competing interests
    The authors declare that no competing interests exist.
  7. 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.

Funding

Ecole des Neurosciences de Paris (PhD Fellowship)

  • Darinka Trübutschek

Fondation Schneider Electric (PhD Fellowship)

  • Darinka Trübutschek

CEA

  • Stanislas Dehaene

INSERM

  • Stanislas Dehaene

Collège de France

  • Stanislas Dehaene

European Research Council (Senior Grant,NeuroConsc)

  • Stanislas Dehaene

Fondation Roger de Spoelberch

  • Stanislas Dehaene

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

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.

Reviewing Editor

  1. Tatiana Pasternak, University of Rochester, United States

Version history

  1. Received: December 2, 2016
  2. Accepted: July 13, 2017
  3. Accepted Manuscript published: July 18, 2017 (version 1)
  4. Version of Record published: September 7, 2017 (version 2)

Copyright

© 2017, Trübutschek 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. Darinka Trübutschek
  2. Sébastien Marti
  3. Andrés Ojeda
  4. Jean-Rémi King
  5. Yuanyuan Mi
  6. Misha Tsodyks
  7. Stanislas Dehaene
(2017)
A theory of working memory without consciousness or sustained activity
eLife 6:e23871.
https://doi.org/10.7554/eLife.23871

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