[1] Weizmann Inst Sci, Dept Neurobiol, IL-76100 Rehovot, Israel
[2] UCL, Inst Cognit Neurosci, London WC1N 3AR, England
[3] Interdisciplinary Ctr IDC, Sch Psychol, IL-46150 Herzliyya, Israel
[4] UCL, Inst Neurol, Natl Hosp Neurol & Neurosurg, Sobell Res Dept Motor Neurosci & Movement Disorde, London WC1N 3BG, England