1. Neuroscience
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A causal role for the precuneus in network-wide theta and gamma oscillatory activity during complex memory retrieval

  1. Melissa Hebscher  Is a corresponding author
  2. Jed A Meltzer
  3. Asaf Gilboa  Is a corresponding author
  1. Northwestern University Feinberg School of Medicine, United States
  2. Rotman Research Institute, Canada
Research Article
  • Cited 27
  • Views 2,684
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Cite this article as: eLife 2019;8:e43114 doi: 10.7554/eLife.43114

Abstract

Complex memory of personal events is thought to depend on coordinated reinstatement of cortical representations by the medial temporal lobes (MTL). MTL-cortical theta and gamma coupling is believed to mediate such coordination, but which cortical structures are critical for retrieval and how they influence oscillatory coupling is unclear. We used magnetoencephalography (MEG) combined with continuous theta burst stimulation (cTBS) to (i) clarify the roles of theta and gamma oscillations in network-wide communication during naturalistic memory retrieval, and (ii) understand the causal relationship between cortical network nodes and oscillatory communication. Retrieval was associated with MTL-posterior neocortical theta phase coupling and theta-gamma phase-amplitude coupling relative to a rest period. Precuneus cTBS altered MTL-neocortical communication by modulating theta and gamma oscillatory coupling. These findings provide a mechanistic account for MTL-cortical communication and demonstrate that the precuneus is a critical cortical node of oscillatory activity, coordinating cross-regional interactions that drive remembering.

Data availability

All data generated during this study are included in the manuscript and supporting files. Source data files have been provided for Figures 2, 3C, and 4C.

The following data sets were generated

Article and author information

Author details

  1. Melissa Hebscher

    Department of Medical Social Sciences, Northwestern University Feinberg School of Medicine, Chicago, United States
    For correspondence
    melhebscher@gmail.com
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-1863-5464
  2. Jed A Meltzer

    Rotman Research Institute, Toronto, Canada
    Competing interests
    The authors declare that no competing interests exist.
  3. Asaf Gilboa

    Rotman Research Institute, Toronto, Canada
    For correspondence
    agilboa@research.baycrest.org
    Competing interests
    The authors declare that no competing interests exist.

Funding

Natural Sciences and Engineering Research Council of Canada (Discovery Grant 378291)

  • Asaf Gilboa

Natural Sciences and Engineering Research Council of Canada (Postgraduate Scholarship- Doctoral)

  • Melissa Hebscher

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

Ethics

Human subjects: The study was approved by the Rotman Research Institute/Baycrest Hospital ethics committee (REB #16-33). All participants provided informed consent prior to participating in the experiment.

Reviewing Editor

  1. David Badre, Brown University, United States

Publication history

  1. Received: October 25, 2018
  2. Accepted: February 9, 2019
  3. Accepted Manuscript published: February 11, 2019 (version 1)
  4. Version of Record published: March 1, 2019 (version 2)

Copyright

© 2019, Hebscher 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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