A compositional neural code in high-level visual cortex can explain jumbled word reading

  1. Aakash Agrawal
  2. KVS Hari
  3. SP Arun  Is a corresponding author
  1. Indian Institute of Science, Bangalore, India


We read jubmled wrods effortlessly, but the neural correlates of this remarkable ability remain poorly understood. We hypothesized that viewing a jumbled word activates a visual representation that is compared to known words. To test this hypothesis, we devised a purely visual model in which neurons tuned to letter shape respond to longer strings in a compositional manner by linearly summing letter responses. We found that dissimilarities between letter strings in this model can explain human performance on visual search, and responses to jumbled words in word reading tasks. Brain imaging revealed that viewing a string activates this letter-based code in the lateral occipital (LO) region and that subsequent comparisons to stored words are consistent with activations of the visual word form area (VWFA). Thus, a compositional neural code potentially contributes to efficient reading.

Data availability

Data and code necessary to reproduce the results are available in an Open Science Framework repository at https://osf.io/384zw/

The following data sets were generated
    1. VisionLabIISc
    (2020) jumbledwordsfMRI
    Open Science Framework, 384zw.

Article and author information

Author details

  1. Aakash Agrawal

    Centre for BioSystems Science and Engineering, Indian Institute of Science, Bangalore, Bangalore, India
    Competing interests
    The authors declare that no competing interests exist.
  2. KVS Hari

    Department of Electrical Communication Engineering, Indian Institute of Science, Bangalore, Bangalore, India
    Competing interests
    The authors declare that no competing interests exist.
  3. SP Arun

    Centre for Neuroscience, Indian Institute of Science, Bangalore, Bangalore, India
    For correspondence
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-9602-5066


Wellcome Trust/DBT India Alliance (IA/S/17/1/503081)

  • SP Arun

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


Human subjects: All subjects gave informed consent to an experimental protocol approved by the Institutional Human Ethics Committee of the Indian Institute of Science (IHEC # 6-15092017).

Reviewing Editor

  1. Chris I Baker, National Institute of Mental Health, National Institutes of Health, United States

Publication history

  1. Received: January 2, 2020
  2. Accepted: May 4, 2020
  3. Accepted Manuscript published: May 5, 2020 (version 1)
  4. Accepted Manuscript updated: May 7, 2020 (version 2)
  5. Version of Record published: June 4, 2020 (version 3)


© 2020, Agrawal 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. Aakash Agrawal
  2. KVS Hari
  3. SP Arun
A compositional neural code in high-level visual cortex can explain jumbled word reading
eLife 9:e54846.

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