A causal role for the precuneus in network-wide theta and gamma oscillatory activity during complex memory retrieval
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.
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Data from: A causal role for the precuneus in network-wide theta and gamma oscillatory activity during complex memory retrievalDryad Digital Repository, doi:10.5061/dryad.gf4f363.
Article and author information
Author details
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.
Reviewing Editor
- David Badre, Brown University, United States
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.
Version history
- Received: October 25, 2018
- Accepted: February 9, 2019
- Accepted Manuscript published: February 11, 2019 (version 1)
- 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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