Functional neurosurgery [electronic resource] : the essentials / Jeffrey A. Brown, MD, FACS, FAANS, Neurosurgery Director, NYU-Winthrop Hospital CyberKnife® Program, Private Practice, Neurological Surgery, PC., Lake Success, New York Julie G. Pilitsis, MD, PhD, Chair, Department of Neuroscience & Experimental Therapeutics, Professor of Neurosurgery, Department of Neurosurgery, Albany Medical College, Albany, New York, Michael Schulder, MD, FAANS, Neurosurgery Program Director, and Vice Chair and Professor, Department of Neurosurgery, Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, Hempstead, New York.