This report has been reviewed in draft form by individuals chosen for their diverse perspectives and technical expertise, in accordance with procedures approved by the National Research Council's Report Review Committee. The purpose of this independent review is to provide candid and critical comments that will assist the institution in making the published report as sound as possible and to ensure that the report meets institutional standards for objectivity, evidence, and responsiveness to the study charge. The review comments and draft manuscript remain confidential to protect the integrity of the deliberative process. We wish to thank the following individuals for their participation in the review of this report: Rene L.Binder, Langley Porter Psychiatric Institute; Ann M.Graybiel, Massachusetts Institute of Technology; Herbert D.Kleber, Columbia University College of Physicians and Surgeons; and Wilkie A.Wilson, Duke University Medical Center.

While the individuals listed above have provided constructive comments and suggestions, it must be emphasized that responsibility for the final content of this report rests entirely with the Board on Neuroscience and Behavioral Health and the Institute of Medicine.