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Typical and atypical language brain organization based on intrinsic connectivity and multitask functional asymmetries

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Cite this article as: eLife 2020;9:e58722 doi: 10.7554/eLife.58722

Abstract

Based on the joint investigation in 287 healthy volunteers (150 Left-Handers (LH)) of language task-induced asymmetries and intrinsic connectivity strength of the sentence-processing supramodal network, we show that individuals with atypical rightward language lateralization (N = 30, 25 LH) do not rely on an organization that simply mirrors that of typical leftward lateralized individuals. Actually, the resting-state organization in the atypicals showed that their sentence processing was underpinned by left and right networks both wired for language processing and highly interacting by strong interhemispheric intrinsic connectivity and larger corpus callosum volume. Such a loose hemispheric specialization for language permits the hosting of language in either the left and/or right hemisphere as assessed by a very high incidence of dissociations across various language task-induced asymmetries in this group.

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Author details

  1. Loïc Labache

    Institut des Maladies Neurodégénératives, UMR5293, Université de Bordeaux, CNRS, CEA, Bordeaux, France
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-5733-0743
  2. Bernard Mazoyer

    Institut des Maladies Neurodégénératives, UMR5293, Université de Bordeaux, CNRS, CEA, Bordeaux, France
    For correspondence
    bernard.mazoyer@u-bordeaux.fr
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-0970-2837
  3. Marc Joliot

    Institut des Maladies Neurodégénératives, UMR5293, Université de Bordeaux, CNRS, CEA, Bordeaux, France
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-7792-308X
  4. Fabrice Crivello

    Institut des Maladies Neurodégénératives, UMR5293, Université de Bordeaux, CNRS, CEA, Bordeaux, France
    Competing interests
    The authors declare that no competing interests exist.
  5. Isabelle Hesling

    Institut des Maladies Neurodégénératives, UMR5293, Université de Bordeaux, CNRS, CEA, Bordeaux, France
    Competing interests
    The authors declare that no competing interests exist.
  6. Nathalie Tzourio-Mazoyer

    Institut des Maladies Neurodégénératives, UMR5293, Université de Bordeaux, CNRS, CEA, Bordeaux, France
    Competing interests
    The authors declare that no competing interests exist.

Funding

Agence Nationale de la Recherche (ANR 16-LCV2-0006-01)

  • Marc Joliot

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 Comité pour la Protection des Personnes dans la Recherche Biomédicale de Basse-Normandie approved the study protocol. All participants gave their informed, written consent, and received an allowance for their participation.

Reviewing Editor

  1. Ingrid S Johnsrude, University of Western Ontario, Canada

Publication history

  1. Received: May 8, 2020
  2. Accepted: October 16, 2020
  3. Accepted Manuscript published: October 16, 2020 (version 1)

Copyright

© 2020, Labache 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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