[1] Aristotle Univ Thessaloniki, Multiple Sclerosis Ctr, Sch Med, Dept Neurol 2, Thessaloniki, Greece
[2] Aristotle Univ Thessaloniki, Sch Med, Dept Psychiat 3, Thessaloniki, Greece
[3] Univ Cyprus, Med Sch, Dept Neurol, Nicosia, Cyprus
[4] Yeshiva Univ, Ferkauf Grad Sch Psychol, Bronx, NY USA
[5] Holy Name Med Ctr, Multiple Sclerosis Ctr, Teaneck, NJ USA
[6] Aristotle Univ Thessaloniki, Dept Neurol 2, GR-54636 Thessaloniki, Greece