Recurrent processes support a cascade of hierarchical decisions

  1. Laura Gwilliams  Is a corresponding author
  2. Jean-Remi King
  1. New York University, United States
  2. École normale supérieure, PSL University, CNRS, France

Abstract

Perception depends on a complex interplay between feedforward and recurrent processing. Yet, while the former has been extensively characterized, the computational organization of the latter remains largely unknown. Here, we use magneto-encephalography to localize, track and decode the feedforward and recurrent processes of reading, as elicited by letters and digits whose level of ambiguity was parametrically manipulated. We first confirm that a feedforward response propagates through the ventral and dorsal pathways within the first 200 ms. The subsequent activity is distributed across temporal, parietal and prefrontal cortices, which sequentially generate five levels of representations culminating in action-specific motor signals. Our decoding analyses reveal that both the content and the timing of these brain responses are best explained by a hierarchy of recurrent neural assemblies, which both maintain and broadcast increasingly rich representations. Together, these results show how recurrent processes generate, over extended time periods, a cascade of decisions that ultimately accounts for subjects' perceptual reports and reaction times.

Data availability

Anonymised source data for figures have been uploaded to Dryad: https://datadryad.org/stash/share/Brtqvoy74YhoHxvaBZMsCeL5JOvWdI_Yuaui5fyIJPA

The following data sets were generated

Article and author information

Author details

  1. Laura Gwilliams

    Psychology, New York University, New York, United States
    For correspondence
    leg5@nyu.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-9213-588X
  2. Jean-Remi King

    Departement d'Etudes Cognitives, École normale supérieure, PSL University, CNRS, Paris, France
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-2121-170X

Funding

William Orr Dingwall Dissertation Fellowship (Dissertation Fellowship)

  • Laura Gwilliams

Abu Dhabi Institute Grant (G1001)

  • Laura Gwilliams

Horizon 2020 Framework Programme (660086)

  • Jean-Remi King

Bettencourt-Schueller Foundation (Bettencourt-Schueller Foundation)

  • Jean-Remi King

Fondation Roger de Spoelberch (Fondation Roger de Spoelberch)

  • Jean-Remi King

Philippe Foundation (Philippe Foundation)

  • Jean-Remi King

National Institutes of Health (R01DC05660)

  • Laura Gwilliams

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

Ethics

Human subjects: This study was ethically approved by the comité de protection des personnes (CPP) IDF 7 under the reference CPP 08 021. All subjects gave written informed consent to participate in this study, which was approved by the local Ethics Committee, in accordance with the Declaration of Helsinki. Participants were compensated for their participation.

Reviewing Editor

  1. Thomas Serre, Brown University, United States

Publication history

  1. Received: March 3, 2020
  2. Accepted: August 30, 2020
  3. Accepted Manuscript published: September 1, 2020 (version 1)
  4. Version of Record published: September 18, 2020 (version 2)

Copyright

© 2020, Gwilliams & King

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. Laura Gwilliams
  2. Jean-Remi King
(2020)
Recurrent processes support a cascade of hierarchical decisions
eLife 9:e56603.
https://doi.org/10.7554/eLife.56603

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