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.