University College London Institute of Neurology, London, United Kingdom
University of Cambridge Dept of Clinical Neurosciences, Cambridge, Cambridgeshire, United Kingdom
Clinical Pharmacology Unit, Box 110, Level 3 ACCI, Addenbrookes Hospital, Cambridge, United Kingdom
Addenbrooke's Hospital, Cambridge, Cambs, United Kingdom
Department of Neurosurgery, Addenbrooke's Hospital, Cambridge, Cambridgeshire, United Kingdom