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Uncovering the functional anatomy of the human insula during speech

  1. Oscar Woolnough  Is a corresponding author
  2. Kiefer James Forseth
  3. Patrick Sarahan Rollo
  4. Nitin Tandon  Is a corresponding author
  1. University of Texas Health Houston, United States
Research Article
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Cite this article as: eLife 2019;8:e53086 doi: 10.7554/eLife.53086

Abstract

The contribution of insular cortex to speech production remains unclear and controversial given diverse findings from functional neuroimaging and lesional data. To create a precise spatiotemporal map of insular activity, we performed a series of experiments: single-word articulations of varying complexity, non-speech orofacial movements and speech listening, in a cohort of 27 patients implanted with penetrating intracranial electrodes. The posterior insula was robustly active bilaterally, but after the onset of articulation, during listening to speech and during production of non-speech mouth movements. Preceding articulation there was very sparse activity, localized primarily to the frontal operculum rather than the insula. Posterior insular was active coincident with superior temporal gyrus, but was more active for self-generated speech than external speech, the opposite of the superior temporal gyrus. These findings support the conclusion that the insula does not serve pre-articulatory preparatory roles.

Data availability

Source data files and a MATLAB plotting function have been provided for Figures 2, 3, 5 and 6.

Article and author information

Author details

  1. Oscar Woolnough

    Vivian L Smith Department of Neurosurgery, McGovern Medical School, University of Texas Health Houston, Houston, United States
    For correspondence
    oscar.woolnough@uth.tmc.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-5878-6865

  2. Kiefer James Forseth

    Vivian L Smith Department of Neurosurgery, McGovern Medical School, University of Texas Health Houston, Houston, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-1624-8329

  3. Patrick Sarahan Rollo

    Vivian L Smith Department of Neurosurgery, McGovern Medical School, University of Texas Health Houston, Houston, United States
    Competing interests
    The authors declare that no competing interests exist.

  4. Nitin Tandon

    Vivian L Smith Department of Neurosurgery, McGovern Medical School, University of Texas Health Houston, Houston, United States
    For correspondence
    Nitin.Tandon@uth.tmc.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-2752-2365

Funding

National Institute on Deafness and Other Communication Disorders (DC014589)

  • Oscar Woolnough
  • Kiefer James Forseth
  • Patrick Sarahan Rollo
  • Nitin Tandon

National Institute of Neurological Disorders and Stroke (NS098981)

  • Oscar Woolnough
  • Kiefer James Forseth
  • Patrick Sarahan Rollo
  • Nitin Tandon

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

Ethics

Human subjects: Patients participated in the experiments after written informed consent was obtained. All experimental procedures were reviewed and approved by the Committee for the Protection of Human Subjects (CPHS) of the University of Texas Health Science Center at Houston as Protocol Number: HSC-MS-06-0385

Reviewing Editor

  1. Barbara G Shinn-Cunningham, Carnegie Mellon University, United States

Publication history

  1. Received: October 27, 2019
  2. Accepted: December 12, 2019
  3. Accepted Manuscript published: December 19, 2019 (version 1)
  4. Version of Record published: January 3, 2020 (version 2)

Copyright

© 2019, Woolnough 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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