Andrea Cancelli1, Carlo Cottone2, Giancarlo Zito3, Marina Di Giorgio4, Patrizio Pasqualetti5, Franca Tecchio6. 1. Laboratory of Electrophysiology for Translational neuroScience (LET'S) - ISTC - CNR, at Department of Neuroscience, Fatebenefratelli Hospital, Rome, Italy Institute of Neurology, Department of Geriatrics, Neurosciences & Orthopaedics, Catholic University of Sacred Heart, Rome, Italy. 2. Laboratory of Electrophysiology for Translational neuroScience (LET'S) - ISTC - CNR, at Department of Neuroscience, Fatebenefratelli Hospital, Rome, Italy Department of Neuroscience and Imaging, G. d'Annunzio University of Chieti - Pescara, Italy. 3. Laboratory of Electrophysiology for Translational neuroScience (LET'S) - ISTC - CNR, at Department of Neuroscience, Fatebenefratelli Hospital, Rome, Italy Department of Clinical Neuroscience, Fatebenefratelli Hospital, Rome, Italy. 4. Department of Clinical Neuroscience, Fatebenefratelli Hospital, Rome, Italy. 5. Medical Statistics and Information Technology, Fatebenefratelli Foundation for Health Research and Education, AFaR Division, Rome, Italy Unit of Neuroimaging, IRCCS San Raffaele Pisana, Rome, Italy. 6. Laboratory of Electrophysiology for Translational neuroScience (LET'S) - ISTC - CNR, at Department of Neuroscience, Fatebenefratelli Hospital, Rome, Italy Unit of Neuroimaging, IRCCS San Raffaele Pisana, Rome, Italy.
Abstract
PURPOSE: Transcranial electric stimulations (tES) with amplitude-modulated currents are promising tools to enhance neuromodulation effects. It is essential to select the correct cortical targets and inhibitory/excitatory protocols to reverse changes in specific networks. We aimed at assessing the dependence of cortical excitability changes on the current amplitude of 20 Hz transcranial alternating current stimulation (tACS) over the bilateral primary motor cortex. METHODS: We chose two amplitude ranges of the stimulations, around 25 μA/cm2 and 63 μA/cm2 from peak to peak, with three values (at steps of about 2.5%) around each, to generate, respectively, inhibitory and excitatory effects of the primary motor cortex. We checked such changes online through transcranial magnetic stimulation (TMS)-induced motor evoked potentials (MEPs). RESULTS: Cortical excitability changes depended upon current density (p = 0.001). Low current densities decreased MEP amplitudes (inhibition) while high current densities increased them (excitation). CONCLUSIONS: tACS targeting bilateral homologous cortical areas can induce online inhibition or excitation as a function of the current density.
PURPOSE: Transcranial electric stimulations (tES) with amplitude-modulated currents are promising tools to enhance neuromodulation effects. It is essential to select the correct cortical targets and inhibitory/excitatory protocols to reverse changes in specific networks. We aimed at assessing the dependence of cortical excitability changes on the current amplitude of 20 Hz transcranial alternating current stimulation (tACS) over the bilateral primary motor cortex. METHODS: We chose two amplitude ranges of the stimulations, around 25 μA/cm2 and 63 μA/cm2 from peak to peak, with three values (at steps of about 2.5%) around each, to generate, respectively, inhibitory and excitatory effects of the primary motor cortex. We checked such changes online through transcranial magnetic stimulation (TMS)-induced motor evoked potentials (MEPs). RESULTS: Cortical excitability changes depended upon current density (p = 0.001). Low current densities decreased MEP amplitudes (inhibition) while high current densities increased them (excitation). CONCLUSIONS: tACS targeting bilateral homologous cortical areas can induce online inhibition or excitation as a function of the current density.
Keywords:
Neuromodulation; motor cortex (M1); neuronavigation; personalized electrode; superficial current density; transcranial alternating current stimulation (tACS)
Authors: Franca Tecchio; Andrea Cancelli; Carlo Cottone; Roberta Ferrucci; Maurizio Vergari; Giancarlo Zito; Patrizio Pasqualetti; Maria Maddalena Filippi; Anna Ghazaryan; Domenico Lupoi; Fenne M Smits; Alessandro Giordani; Simone Migliore; Camillo Porcaro; Carlo Salustri; Paolo M Rossini; Alberto Priori Journal: Front Neurol Date: 2015-07-03 Impact factor: 4.003
Authors: Camillo Porcaro; Carlo Cottone; Andrea Cancelli; Paolo M Rossini; Giancarlo Zito; Franca Tecchio Journal: Sci Rep Date: 2019-12-03 Impact factor: 4.379