TITLE
Does Transcranial Alternating Current Stimulation Induce Cerebellum Plasticity? Feasibility, Safety and Efficacy of a Novel Electrophysiological Approach
AUTHORS
Naro A; Leo A; Russo M; Cannavo A; Milardi D; Bramanti P; Calabro RS. Institution Naro, Antonino. IRCCS Centro Neurolesi “Bonino-Pulejo”, Messina, Italy. Leo, Antonino. IRCCS Centro Neurolesi “Bonino-Pulejo”, Messina, Italy. Russo, Margherita. IRCCS Centro Neurolesi “Bonino-Pulejo”, Messina, Italy. Cannavo, Antonino. IRCCS Centro Neurolesi “Bonino-Pulejo”, Messina, Italy. Milardi, Demetrio. IRCCS Centro Neurolesi “Bonino-Pulejo”, Messina, Italy; Department of Biomedical Sciences and Morphological and Functional Images, University of Messina, Italy. Bramanti, Placido. IRCCS Centro Neurolesi “Bonino-Pulejo”, Messina, Italy. Calabro, Rocco Salvatore. IRCCS Centro Neurolesi “Bonino-Pulejo”, Messina, Italy.
ELECTRONIC ADDRESS
salbro77@tiscali.it
SOURCE
Brain Stimulation. 9(3):388-395, 2016 May-Jun.
BACKGROUND
Cerebellum-brain functional connectivity can be shaped through different non-invasive neurostimulation approaches. In this study, we propose a novel approach to perturb the cerebellum-brain functional connectivity by means of transcranial alternating current stimulation (tACS).
METHODS
Twenty-five healthy individuals underwent a cerebellar tACS protocol employing different frequencies (10, 50, and 300Hz) and a sham-tACS over the right cerebellar hemisphere. We measured their after-effects on the motor evoked potential (MEP) amplitude, the cerebellum-brain inhibition (CBI), the long-latency intracortical inhibition (LICI), from the primary motor cortex of both the hemispheres. In addition, we assessed the functional adaptation to a right hand sequential tapping motor task.
RESULTS
None of the participants had any side-effect. Following 50Hz-tACS, we observed a clear contralateral CBI weakening, paralleled by a MEP increase with a better adaptation to frequency variations during the sequential tapping. The 300Hz-tACS induced a contralateral CBI strengthening, without significant MEP and kinematic after-effects. The 10Hz-tACS conditioning was instead ineffective.
CONCLUSIONS
We may argue that tACS protocols could have interfered with the activity of CBI-sustaining Purkinje cell, affecting motor adaptation. Our safe approach seems promising in studying the cerebellum-brain functional connectivity, with possible implications in neurorehabilitative settings.
Copyright © 2016 Elsevier Inc. All rights reserved.
