Shorter cortical adaptation in dyslexia is broadly distributed in the superior temporal lobe and includes the primary auditory cortex

  1. Sagi Jaffe-Dax  Is a corresponding author
  2. Eva Kimel
  3. Merav Ahissar
  1. Princeton University, United States
  2. The Hebrew University of Jerusalem, Israel

Abstract

Studies of performance of individuals with dyslexia on perceptual tasks suggest that their implicit inference of sound statistics is impaired. Previously, using two-tone frequency discrimination, we found that the effect of previous trials' frequencies on judgments of individuals with dyslexia decayed faster than the effect on controls' judgments, and that the adaptation (decrease of neural response to repeated stimuli) of their ERP responses to tones was shorter (Jaffe-Dax et al., 2017). Here, we show the cortical distribution of this abnormal dynamics of adaptation using fast acquisition fMRI. We find that faster decay of adaptation in dyslexia is widespread, though the most significant effects are found in the left superior temporal lobe, including the auditory cortex. This broad distribution suggests that the faster decay of implicit memory of individuals with dyslexia is a general characteristic of their cortical dynamics, which affects also sensory cortices.

Article and author information

Author details

  1. Sagi Jaffe-Dax

    Department of Psychology, Princeton University, Princeton, United States
    For correspondence
    jaffedax@princeton.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-8759-6980
  2. Eva Kimel

    Edmond And Lily Safra Center for Brain Sciences, The Hebrew University of Jerusalem, Jerusalem, Israel
    Competing interests
    The authors declare that no competing interests exist.
  3. Merav Ahissar

    Edmond And Lily Safra Center for Brain Sciences, The Hebrew University of Jerusalem, Jerusalem, Israel
    Competing interests
    The authors declare that no competing interests exist.

Funding

Israel Science Foundation (616/11)

  • Merav Ahissar

Gatsby Charitable Foundation

  • Merav Ahissar

German-Israeli Foundation for Scientific Research and Development (I-1303-105.4/2015)

  • Merav Ahissar

Israel Science Foundation (2425/15)

  • Merav Ahissar

Canadian Institute for Advanced Research

  • Merav Ahissar

Azrieli Foundation

  • Merav Ahissar

International Development Research Centre

  • Merav Ahissar

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

Ethics

Human subjects: Informed consent was acquired from all participants. The study was approved by The Hebrew University Committee for the Use of Human Subject in Research.

Reviewing Editor

  1. Andrew J King, University of Oxford, United Kingdom

Publication history

  1. Received: November 15, 2017
  2. Accepted: February 27, 2018
  3. Accepted Manuscript published: February 28, 2018 (version 1)
  4. Version of Record published: March 20, 2018 (version 2)

Copyright

© 2018, Jaffe-Dax 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. Sagi Jaffe-Dax
  2. Eva Kimel
  3. Merav Ahissar
(2018)
Shorter cortical adaptation in dyslexia is broadly distributed in the superior temporal lobe and includes the primary auditory cortex
eLife 7:e30018.
https://doi.org/10.7554/eLife.30018

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