Abdul Q. Rana, MD, FRCPC, Consultant Neurologist and Director, Parkinson’s Clinic of Eastern Toronto & Movement Disorders Centre, Toronto, Ontario, Canada Dr Rana is author of two other Springer books: Neurological Emergencies in Clinical Practice and Neuroradiology in Clinical Practice.Peter Hedera, MD, PhD, Associate Professor, Department of Neurology, Division of Movement Disorders, Vanderbilt University, Nashville, TN, USA