Typical and atypical language brain organization based on intrinsic connectivity and multitask functional asymmetries
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.
All data generated or analysed during this study are included in the manuscript and supporting files. Source data files have been provided for all figures and tables
BIL&GIN Sentence and Rest asymmetries - eLifeDryad Digital Repository, doi:10.5061/dryad.ht76hdrcf.
Article and author information
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.
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.
- Ingrid S Johnsrude, University of Western Ontario, Canada
- Received: May 8, 2020
- Accepted: October 16, 2020
- Accepted Manuscript published: October 16, 2020 (version 1)
- Version of Record published: November 2, 2020 (version 2)
© 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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