Norman E. Rosenthal, M.D., is a clinical professor of psychiatry at Georgetown Medical School and the author of "Transcendence: Healing and Transformation through Transcendental Meditation" and "Winter Blues" (among others). He conducted research at the National Institute of Mental Health, as a Research Fellow, Researcher, and Senior Researcher for over twenty years. It was there that he first described and diagnosed Seasonal Affective Disorder (SAD). Dr. Rosenthal has received the prestigious Anna Monika Foundation Research prize for his contribution to research in treating depression and has been listed in The Best Doctors in America and the Consumers’ Research Council of America’s Guide to America’s Top Psychiatrists. Rosenthal is the author or co-author of over 200 professional articles. He can be found online at www.normanrosenthal.com.