Arthur P. Hays, MD is Associate Professor of Clinical Neuropathology and is Director of the Muscle & Nerve Laboratory of the Division of Neuropathology at Columbia Presbyterian Medical Center. He evaluates nerve and muscle biopsies for diagnostic purposes and has specialized in amyotrophic lateral sclerosis (ALS) for over 15 years. His research has focused on the pathology of ALS and the potentially treatable disorder, multifocal motor neuropathy. He is also investigating the role of the cytoskeletal proteins, neurofilament protein and peripherin, in motor nerve cells of patients with ALS.