Event Abstract Back to Event Transcranial Direct Current Stimulation with an M1 / Orbitofrontal Montage shows No Effect on Simple Visual Motor Reaction Time Jared Horvath1*, Olivia Carter1 and Jason Forte1 1 University of Melbourne, Psychological Sciences, Australia Background During the past fifteen years, several lines of evidence have emerged that suggest transcranial direct current stimulation (tDCS) of the motor cortex can modulate corticospinal excitability as measured using varied evoked muscular potential paradigms. Unfortunately, evidence as to whether or not these physiological changes lead to commensurate behavioral effects is heavily conflicted. To address this, we systematically examined the effects of an M1 / Orbitofrontal tDCS montage on a well-elucidate neurobehavioral system: short duration simple visual motor reaction time (RT). Methods Fifty healthy participants were randomly divided into five groups: 2 mA anodal, 2 mA cathodal, 1 mA anodal, 1 mA cathodal, and sham tDCS (20 minutes stimulation time). Starting ~5 minutes prior to stimulation and running continuously for ~30 minutes, participants were repeatedly presented with an easily perceivable gabor patch centered on a computer monitor and asked to press a response button as quickly as possible at onset of stimuli (stimuli number: 100 pre-, 400 during-, and 100-post stimulation - interstimulus interval: 1-3 seconds). Medians were determined for each batch of 100 RTs, normalized to pre-stimulation levels, and compared using a two-way ANOVA. Results Although each group completed the experiment with a significantly slower reaction time than at the start (F(5, 270)=8.966, p<0.001: suggesting a boredom effect), there were no significant effects of stimulation type on RT times (F(4, 270)=0.637, p=0.636) nor significant interaction effects (F(20, 270)=0.414, p=0.989). Discussion Our results suggest that an M1 / Orbitofrontal tDCS montage, regardless of stimulation strength, does not modulate short duration simple visual motor reaction time. This finding raises interesting questions with regards to the utility and behavioral translatability of the often reported physiological modulations generated by tDCS. In addition, our finding calls into question the simplistic mechanisms by which several researchers have argued motor behavioral modulation by tDCS may be generated. However, our findings do not rule out the possibility that other tDCS parameters (such as varied electrode montages or stimulation durations) may have an effect on simple Keywords: Reaction Time, transcranial direct current stimulation (tDCS), Brain Stimulation, motor behavior, Simple RT Conference: XII International Conference on Cognitive Neuroscience (ICON-XII), Brisbane, Queensland, Australia, 27 Jul - 31 Jul, 2014. Presentation Type: Poster Topic: Motor Behaviour Citation: Horvath J, Carter O and Forte J (2015). Transcranial Direct Current Stimulation with an M1 / Orbitofrontal Montage shows No Effect on Simple Visual Motor Reaction Time. Conference Abstract: XII International Conference on Cognitive Neuroscience (ICON-XII). doi: 10.3389/conf.fnhum.2015.217.00180 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 19 Feb 2015; Published Online: 24 Apr 2015. * Correspondence: Mr. Jared Horvath, University of Melbourne, Psychological Sciences, Melbourne, Australia, jch155@mail.harvard.edu Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers Jared Horvath Olivia Carter Jason Forte Google Jared Horvath Olivia Carter Jason Forte Google Scholar Jared Horvath Olivia Carter Jason Forte PubMed Jared Horvath Olivia Carter Jason Forte Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.