A student and practitioner of Buddhism since the early 1960s, PAUL DENNISON, PhD, is a founding member and former chairman of the Samatha Trust, an organization dedicated to the preservation and teaching of Buddhist samatha meditation. He has been a research physicist, a goldsmith and gem dealer, a monk in rural Thailand, and, for the past two and a half decades, a psychotherapist and psychoanalyst. He is also currently an independent researcher on the neuroscience of meditation and consciousness.