1. Department of Neurosciences, University of Turin, Via Cherasco 15, 10100 Torino, Italy
2. Institute of Electronics, Information Engineering and Telecommunication, National Research Council, Corso Duca degli Abruzzi 24, 10129 Torino, Italy
3. Department of Control and Computer Engineering, Politecnico di Torino, Corso Duca degli Abruzzi 24, 10129 Torino, Italy
4. Istituto Auxologico Italiano, IRCCS, Department of Neurology and Neurorehabilitation, S. Giuseppe Hospital, Oggebbio (Piancavallo), 28824 Verbania, Italy