Neural mechanisms underlying perilesional transcranial direct current stimulation in aphasia: A feasibility study

Ulm, Lena, McMahon, Katie, Copland, David, de Zubicaray, Greig I., & Meinzer, Marcus (2015) Neural mechanisms underlying perilesional transcranial direct current stimulation in aphasia: A feasibility study. Frontiers in Human Neuroscience, 9, Article Number-550.

View at publisher (open access)

Abstract

Little is known about the neural mechanisms by which transcranial direct current stimulation (tDCS) impacts on language processing in post-stroke aphasia. This was addressed in a proof-of-principle study that explored the effects of tDCS application in aphasia during simultaneous functional magnetic resonance imaging (fMRI). We employed a single subject, cross-over, sham-tDCS controlled design, and the stimulation was administered to an individualized perilesional stimulation site that was identified by a baseline fMRI scan and a picture naming task. Peak activity during the baseline scan was located in the spared left inferior frontal gyrus and this area was stimulated during a subsequent cross-over phase. tDCS was successfully administered to the target region and anodal- vs. sham-tDCS resulted in selectively increased activity at the stimulation site. Our results thus demonstrate that it is feasible to precisely target an individualized stimulation site in aphasia patients during simultaneous fMRI, which allows assessing the neural mechanisms underlying tDCS application. The functional imaging results of this case report highlight one possible mechanism that may have contributed to beneficial behavioral stimulation effects in previous clinical tDCS trials in aphasia. In the future, this approach will allow identifying distinct patterns of stimulation effects on neural processing in larger cohorts of patients. This may ultimately yield information about the variability of tDCS effects on brain functions in aphasia.

Impact and interest:

3 citations in Scopus
Search Google Scholar™
3 citations in Web of Science®

Citation counts are sourced monthly from Scopus and Web of Science® citation databases.

These databases contain citations from different subsets of available publications and different time periods and thus the citation count from each is usually different. Some works are not in either database and no count is displayed. Scopus includes citations from articles published in 1996 onwards, and Web of Science® generally from 1980 onwards.

Citations counts from the Google Scholar™ indexing service can be viewed at the linked Google Scholar™ search.

Full-text downloads:

11 since deposited on 15 Apr 2016
11 in the past twelve months

Full-text downloads displays the total number of times this work’s files (e.g., a PDF) have been downloaded from QUT ePrints as well as the number of downloads in the previous 365 days. The count includes downloads for all files if a work has more than one.

ID Code: 94874
Item Type: Journal Article
Refereed: Yes
Keywords: Anomia, Aphasia, functional magnetic resonance imaging, stroke, transcranial direct current stimulation
DOI: 10.3389/fnhum.2015.00550
ISSN: 1662-5161
Divisions: Current > QUT Faculties and Divisions > Faculty of Health
Funding:
Copyright Owner: Copyright 2015 Ulm, McMahon, Copland, de Zubicaray and Meinzer.
Copyright Statement: This is an
open-access article distributed under the terms of the Creative Commons Attribution
License (CC BY). The use, distribution or reproduction in other forums is permitted,
provided the original author(s) or licensor are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use,
distribution or reproduction is permitted which does not comply with these terms.
Deposited On: 15 Apr 2016 01:35
Last Modified: 17 Apr 2016 21:29

Export: EndNote | Dublin Core | BibTeX

Repository Staff Only: item control page