Bruce S. McEwen, Ph.D., is the Alfred E. Mirsky Professor and head of the Harold and Margaret Milliken Hatch Laboratory of Neuroendocrinology at The Rockefeller University. He is a member of the National Academy of Sciences, the Institute of Medicine, and the American Academy of Arts and Sciences, and a fellow of the New York Academy of Sciences. As a neuroscientist and neuroendocrinologist, Dr. McEwen’s laboratory discovered adrenal steroid receptors in the hippocampus in 1968. His current research focuses on stress’ effects on the amygdala, prefrontal cortex, and hippocampus, along with sex-hormone effects and sex differences in these brain regions. Dr. McEwen is author of The End of Stress as We Know It (Dana Press/Joseph Henry Press, 2002) and The Hostage Brain (The Rockefeller University Press, 1994).