1. Department of Neurology, Inselspital, University Hospital Bern, University of Bern, Bern, Switzerland
2. Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, Maryland
3. Department of Otorhinolaryngology, Head and Neck Surgery, Inselspital, University Hospital Bern, University of Bern, Bern, Switzerland
4. Laboratory of Bioengineering, Department of Electrical, Computer and Biomedical Engineering, University of Pavia, Pavia, Italy