Convergent and divergent brain structural and functional abnormalities associated with developmental dyslexia

  1. Xiaohui Yan
  2. Ke Jiang
  3. Hui Li
  4. Ziyi Wang
  5. Kyle Perkins
  6. Fan Cao  Is a corresponding author
  1. Sun Yat-sen University, China
  2. Sun Yat-Sen University, China
  3. Anyang Preschool Education College, China
  4. Jining University, China
  5. Florida International University, United States

Abstract

Brain abnormalities in the reading network have been repeatedly reported in individuals with developmental dyslexia (DD); however, it is still not totally understood where the structural and functional abnormalities are consistent/inconsistent across languages. In the current multimodal meta-analysis, we found convergent structural and functional alterations in the left superior temporal gyrus across languages, suggesting a neural signature of DD. We found greater reduction in grey matter volume and brain activation in the left inferior frontal gyrus in morpho-syllabic languages (e.g. Chinese) than in alphabetic languages, and greater reduction in brain activation in the left middle temporal gyrus and fusiform gyrus in alphabetic languages than in morpho-syllabic languages. These language differences are explained as consequences of being DD while learning a specific language. In addition, we also found brain regions that showed increased grey matter volume and brain activation, presumably suggesting compensations and brain regions that showed inconsistent alterations in brain structure and function. Our study provides important insights about the etiology of DD from a cross-linguistic perspective with considerations of consistency/inconsistency between structural and functional alterations.

Data availability

All data generated or analysed during this study are included in the manuscript and supporting files. Meta-analysis data is deposited to Dryad.

The following data sets were generated
    1. Yan X
    (2021) meta-analysis data
    Dryad Digital Repository, doi:10.5061/dryad.0p2ngf222.

Article and author information

Author details

  1. Xiaohui Yan

    Sun Yat-sen University, Guangzhou, China
    Competing interests
    The authors declare that no competing interests exist.
  2. Ke Jiang

    Sun Yat-Sen University, Guangzhou, China
    Competing interests
    The authors declare that no competing interests exist.
  3. Hui Li

    Anyang Preschool Education College, Anyang, China
    Competing interests
    The authors declare that no competing interests exist.
  4. Ziyi Wang

    Jining University, Jining, China
    Competing interests
    The authors declare that no competing interests exist.
  5. Kyle Perkins

    Florida International University, Florida, United States
    Competing interests
    The authors declare that no competing interests exist.
  6. Fan Cao

    Sun Yat-sen University, Guangzhou, China
    For correspondence
    caofan3@mail.sysu.edu.cn
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-3786-1600

Funding

Fundamental Research Funds for the Central Universities

  • Fan Cao

Guangdong Planning Office of Philosophy and Social Science (GD19CXL05)

  • Fan Cao

Science and Technology Program of Guangzhou, China, Key Area Research and Development Program (202007030011)

  • Fan Cao

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

Reviewing Editor

  1. Ruth de Diego-Balaguer, Universitat de Barcelona, Spain

Publication history

  1. Received: April 17, 2021
  2. Preprint posted: May 10, 2021 (view preprint)
  3. Accepted: September 24, 2021
  4. Accepted Manuscript published: September 27, 2021 (version 1)
  5. Version of Record published: October 7, 2021 (version 2)

Copyright

© 2021, Yan 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. Xiaohui Yan
  2. Ke Jiang
  3. Hui Li
  4. Ziyi Wang
  5. Kyle Perkins
  6. Fan Cao
(2021)
Convergent and divergent brain structural and functional abnormalities associated with developmental dyslexia
eLife 10:e69523.
https://doi.org/10.7554/eLife.69523

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