Tagging motor memories with transcranial direct current stimulation allows later artificially-controlled retrieval
Abstract
We demonstrate that human motor memories can be artificially tagged and later retrieved by noninvasive transcranial direct-current stimulation (tDCS). Participants learned to adapt reaching movements to two conflicting dynamical environments that were each associated with a different tDCS polarity (anodal or cathodal tDCS) on the sensorimotor cortex. That is, we sought to determine whether divergent background activity levels within the sensorimotor cortex (anodal: higher activity; cathodal: lower activity) give rise to distinct motor memories. After a training session, application of each tDCS polarity automatically resulted in the retrieval of the motor memory corresponding to that polarity. These results reveal that artificial modulation of neural activity in the sensorimotor cortex through tDCS can act as a context for the formation and recollection of motor memories.
Article and author information
Author details
Funding
Ministry of Education, Culture, Sports, Science, and Technology (KAKENHI A26242062)
- Daichi Nozaki
- Masaya Hirashima
NEXT Program (LS034)
- Daichi Nozaki
Japan Society for the Promotion of Science (Japan-Belgium Research Cooperative Program)
- Daichi Nozaki
- Jean-Jacques Orban de Xivry
Brains Back to Brussels fellowship
- Jean-Jacques Orban de Xivry
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- Richard Ivry, University of California, Berkeley, United States
Ethics
Human subjects: The experiments were conducted in accordance with the Declaration of Helsinki. The ethics committee from The University of Tokyo approved all experimental procedures. Prior to the experiments, participants provided informed consent.
Version history
- Received: February 19, 2016
- Accepted: July 28, 2016
- Accepted Manuscript published: July 29, 2016 (version 1)
- Version of Record published: August 22, 2016 (version 2)
- Version of Record updated: September 2, 2016 (version 3)
Copyright
© 2016, Nozaki 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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