1 Department of Neurology, Hochzirl Hospital, Zirl, Austria. Electronic address: markus.kofler@i-med.ac.at.
2 National Institute of Neurological Disorders and Stroke, NIH, USA. Electronic address: hallettm@ninds.nih.gov.
3 University College London, United Kingdom; Italian Institute of Technology (IIT), Rome, Italy. Electronic address: giandomenico.iannetti@gmail.com.
4 Department of Neurorehabilitation, Hospital of Vipiteno (SABES-ASDAA), Teaching Hospital of the Paracelsus Medical Private University (PMU), Vipiteno-Sterzing, Italy. Electronic address: viviana.versace@sabes.it.