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Editor: Roger N. Rosenberg, MD Department of Neurology University of Texas Southwestern Medical Center 5323 Harry Hines Blvd Dallas, TX 75390-9108

Associate Editors: Hassan M. Fathallah-Shaykh, MD, PhD, Birmingham, Alabama Lawrence S. Honig, MD, PhD, New York, New York Olaf Stüve, MD, PhD, Dallas, Texas Matthew Menken, MD, Princeton, New Jersey David E. Pleasure, MD, Sacramento, California E. S. Roach, MD, Columbus, Ohio Ira Shoulson, MD, Rochester, New York

Editorial Assistant: Yeong-Hee Shin, Dallas, Texas Editorial Office: (214) 648-9383 fax: (214) 648-9388 e-mail: archneurol@jama-archives.org

Neurological Review Editor: David E. Pleasure, MD, Sacramento, California Commentary in Neurology Editor: E. S. Roach, MD, Columbus, Ohio Clinical Implications of Basic Neuroscience Research Editor: Hassan M. Fathallah-Shaykh, MD, PhD, Birmingham, Alabama Clinical Trials Editor: Ira Shoulson, MD, Rochester, New York Neurology and Public Health Editor: Matthew Menken, MD, Princeton, New Jersey Book Reviews Editor: Olaf Stüve, MD, PhD, Dallas, Texas Web Editor: Lawrence S. Honig, MD, PhD, New York, New York CME Editor: Matthew Menken, MD, Princeton, New Jersey

James I. Ausman, MD, PhD, Rancho Mirage, California Louis R. Caplan, MD, Boston, Massachusetts Helena C. Chui, MD, Los Angeles, California Steven T. DeKosky, MD, Charlottesville, Virginia James A. Ferrendelli, MD, Houston, Texas John H. Growdon, MD, Boston, Massachusetts Vladimir Hachinski, MD, DSc, London, Ontario Audrey S. Penn, MD, Bethesda, Maryland Stanley B. Prusiner, MD, San Francisco, California Michael K. Racke, MD, Columbus, Ohio Mya C. Schiess, MD, Houston, Texas Thomas R. Swift, MD, Augusta, Georgia Kenneth L. Tyler, MD, Denver, Colorado Paul C. Van Ness, MD, Dallas, Texas

Johan A. Aarli, MD, Bergen, Norway Oded Abramsky, MD, PhD, Jerusalem, Israel Samir F. Atweh, MD, Beirut, Lebanon Paula Coutinho, MD, PhD, Porto, Portugal Alexandra Dürr, MD, Paris, France Bruno Estanol, MD, Mexico City, Mexico Cesare Fieschi, MDN, Rome, Italy Wang Guo-Xiang, MD, Beijing, China Bernhard Hemmer, MD, Munich, Germany Sang-Bok Lee, MD, PhD, Seoul, Korea Olle Lindvall, MD, PhD, Lund, Sweden Colin Masters, MD, Melbourne, Victoria, Australia Sergio Novis, MD, Rio de Janeiro, Brazil Michael Piradov, MD, Moscow, Russia Niphon Poungvarin, MD, FRCP, Bangkok, Thailand Anthony H. V. Schapira, DSc, MD, FRCP, London, England Bhim S. Singhal, MD, Bombay, India Eduardo Tolosa, MD, Barcelona, Spain Shoji Tsuji, MD, PhD, Tokyo, Japan

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