Spatially bivariate EEG-neurofeedback can manipulate interhemispheric inhibition
Abstract
Human behavior requires interregional crosstalk to employ the sensorimotor processes in the brain. Although external neuromodulation techniques have been used to manipulate interhemispheric sensorimotor activity, a central controversy concerns whether this activity can be volitionally controlled. Experimental tools lack the power to up- or down-regulate the state of the targeted hemisphere over a large dynamic range and, therefore, cannot evaluate the possible volitional control of the activity. We addressed this difficulty by using the recently developed method of spatially bivariate electroencephalography (EEG)-neurofeedback to systematically enable the participants to modulate their bilateral sensorimotor activities. Herein, we report that participants learn to up- and down-regulate the ipsilateral excitability to the imagined hand while maintaining constant the contralateral excitability; this modulates the magnitude of interhemispheric inhibition (IHI) assessed by the paired-pulse transcranial magnetic stimulation (TMS) paradigm. Further physiological analyses revealed that the manipulation capability of IHI magnitude reflected interhemispheric connectivity in EEG and TMS, which was accompanied by intrinsic bilateral cortical oscillatory activities. Our results show an interesting approach for neuromodulation, which might identify new treatment opportunities, for example, in patients suffering from a stroke.
Data availability
Source data used to generate the figures are publicly available via Dryad Digital Repository, accessible here:Hayashi, Masaaki (2021), Spatially bivariate EEG-neurofeedback can manipulate interhemispheric rebalancing of M1 excitability, Dryad, Dataset, https://doi.org/10.5061/dryad.hhmgqnkj3Scripts used for the neurofeedback experiment are available on GitHub (https://github.com/MasaakiHayashi/elife-neurofeedback-experiment).
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Data from Spatially bivariate EEG-neurofeedback can manipulate interhemispheric rebalancing of M1 excitabilityDryad Digital Repository, doi:10.5061/dryad.hhmgqnkj3.
Article and author information
Author details
Funding
Ministry of Education, Culture, Sports, Science and Technology (Grant-in-Aid for Transformative Research Areas (A) (#20H05923))
- Junichi Ushiba
Japan Agency for Medical Research and Development (Strategic International Brain Science Research Promotion Program (#JP20dm030702))
- Junichi Ushiba
Ushioda Memorial Fund (The Keio University Doctorate Student Grant-in-Aid Program)
- Masaaki Hayashi
Japan Science and Technology Agency (Moonshot R&D program (Grant Number JPMJMS2012))
- Junichi Ushiba
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 experiments conformed to the Declaration of Helsinki and were performed in accordance with the current TMS safety guidelines of the International Federation of Clinical Neurophysiology (Rossi et al., 2009). The experimental procedure was approved by the Ethics Committee of the Faculty of Science and Technology, Keio University (no.: 31-89, 2020-38, and 2021-74). Written informed consent was obtained from participants prior to the experiments.
Copyright
© 2022, Hayashi 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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