[1] Tel Aviv Sourasky Med Ctr, Movement Disorders Unit, Dept Neurol, IL-64239 Tel Aviv, Israel
[2] Tel Aviv Univ, Sackler Sch Med, Dept Phys Therapy, IL-69978 Tel Aviv, Israel
[3] Harvard Univ, Sch Med, Div Aging, Boston, MA 02115 USA
[4] Tel Aviv Univ, Sackler Sch Med, Dept Neurol, IL-69978 Tel Aviv, Israel