title: Evaluation of a Modified High-Definition Electrode Montage for Transcranial Alternating Current Stimulation (tACS) of Pre-Central Areas.
abstract: To evaluate a modified electrode montage with respect to its effect on tACS-dependent modulation of corticospinal excitability and discomfort caused by neurosensory side effects accompanying stimulation.
  
  
  
  In a double-blind cross-over design, the classical electrode montage for primary motor cortex (M1) stimulation (two patch electrodes over M1 and contralateral supraorbital area) was compared with an M1 centre-ring montage. Corticospinal excitability was evaluated before, during, immediately after and 15 minutes after tACS (10 min., 20 Hz vs. 30 s low-frequency transcranial random noise stimulation).
  
  
  
  Corticospinal excitability increased significantly during and immediately after tACS with the centre-ring montage. This was not the case with the classical montage or tRNS stimulation. Level of discomfort was rated on average lower with the centre-ring montage.
  
  
  
  In comparison to the classic montage, the M1 centre-ring montage enables a more focal stimulation of the target area and, at the same time, significantly reduces neurosensory side effects, essential for placebo-controlled study designs.
authors.affiliation: Movement Control and Neuroplasticity Research Group, Department of Kinesiology, KU Leuven, Tervuurse Vest 101, 3001 Leuven, Belgium. Electronic address: kirstin.heise@kuleuven.be.
authors.forename: Kirstin-Friederike
authors.initials: KF
authors.lastname: Heise
authors.affiliation: Movement Control and Neuroplasticity Research Group, Department of Kinesiology, KU Leuven, Tervuurse Vest 101, 3001 Leuven, Belgium.
authors.forename: Nick
authors.initials: N
authors.lastname: Kortzorg
authors.affiliation: Danish Research Centre for Magnetic Resonance, Copenhagen University Hospital Hvidovre, Kettegård Allé 30, DK-2650 Hvidovre, Denmark; DTU Elektro, Technical University of Denmark, Ørsteds Plads, Bygning 349, DK-2800 Kongens Lyngby, Denmark.
authors.forename: Guilherme Bicalho
authors.initials: GB
authors.lastname: Saturnino
authors.affiliation: Movement Control and Neuroplasticity Research Group, Department of Kinesiology, KU Leuven, Tervuurse Vest 101, 3001 Leuven, Belgium.
authors.forename: Hakuei
authors.initials: H
authors.lastname: Fujiyama
authors.affiliation: Movement Control and Neuroplasticity Research Group, Department of Kinesiology, KU Leuven, Tervuurse Vest 101, 3001 Leuven, Belgium; REVAL Rehabilitation Research Centre, Biomedical Research Institute, Faculty of Medicine and Life Sciences, Hasselt University, Diepenbeek, Belgium.
authors.forename: Koen
authors.initials: K
authors.lastname: Cuypers
authors.affiliation: Danish Research Centre for Magnetic Resonance, Copenhagen University Hospital Hvidovre, Kettegård Allé 30, DK-2650 Hvidovre, Denmark; DTU Elektro, Technical University of Denmark, Ørsteds Plads, Bygning 349, DK-2800 Kongens Lyngby, Denmark; Max Planck Institute for Biological Cybernetics, Tübingen, Germany.
authors.forename: Axel
authors.initials: A
authors.lastname: Thielscher
authors.affiliation: Movement Control and Neuroplasticity Research Group, Department of Kinesiology, KU Leuven, Tervuurse Vest 101, 3001 Leuven, Belgium; Leuven Research Institute for Neuroscience & Disease (LIND), KU Leuven, Belgium.
authors.forename: Stephan P
authors.initials: SP
authors.lastname: Swinnen
mesh_terms: D000328:Adult; D018592:Cross-Over Studies; D004311:Double-Blind Method; D004566:Electrodes; D004867:Equipment Design; D005260:Female; D006801:Humans; D008297:Male; D009044:Motor Cortex / Q000502:physiology*; D065908:Transcranial Direct Current Stimulation / Q000295:instrumentation*; D055815:Young Adult
keywords: Beta frequency; Corticospinal excitability; High-density electrode montage; Neurosensory effects; Transcranial alternating current stimulation