1. Department of Neurosurgery (MPP, PM, LG, ICC), Royal Victoria Infirmary, Newcastle; Transitional and Clinical Research Institute (MPP, IAW), Newcastle University, Newcastle; Department of Neurology (KTY), National Hospital for Neurology and Neurosurgery, London; Nuffield Department of Clinical Neurosciences (KTY), John Radcliffe Hospital, Oxford; and Department of Clinical Neuropsychology (IAW), Royal Victoria Infirmary, Newcastle, United Kingdom.