Aldous Huxley called humankind's basic trend toward spiritual growth the "perennial philosophy." In the view of James Austin, the trend implies a "perennial psychophysiology" -- because awakening, or enlightenment, occurs only when the human brain undergoes substantial changes. What are the peak experiences of enlightenment? How could these states profoundly enhance, and yet simplify, the workings of the brain? Zen and the Brain presents the latest evidence. In this book Zen Buddhism becomes the opening wedge for an extraordinarily wide-ranging exploration of consciousness. In order to understand which brain mechanisms produce Zen states, one needs some understanding of the anatomy, physiology, and chemistry of the brain. Austin, both a neurologist and a Zen practitioner, interweaves the most recent brain research with the personal narrative of his Zen experiences. The science is both inclusive and rigorous; the Zen sections are clear and evocative. Along the way, Austin examines such topics as similar states in other disciplines and religions, sleep and dreams, mental illness, consciousness-altering drugs, and the social consequences of the advanced stage of ongoing enlightenment.