Why do people have near-death experiences? Are there physical explanations for those out-of-body sensations and tunnels of light? And what about moments of spiritual ecstasy? If Buddha had been in an MRI machine and not under the Bodhi tree when he attained enlightenment, what would we have seen on the monitor?

Kevin Nelson, a neurologist with three decades' experience examining the biology behind human spirituality, deconstructs the spiritual self, uncovering its origin in the most primitive areas of our brain. Through his revolutionary studies on near-death experience, Nelson has discovered that spiritual experience is an incidental product of several different neurological processes acting independently. When we feel close to God or sense the presence of departed relatives, we may believe that we are standing at the border of this world and the next as individual, autonomous, rational creatures-touching God. The reality is far different: our brain function resembles a Cubist painting by Picasso or Braque, and the experiences we regard as the height of our humanity are in fact produced by primal reflexes.

Nelson takes us on a journey into what he calls the borderlands of consciousness. The book offers the first comprehensive, empirically-tested, peer-reviewed examination of the reasons we are capable of near-death experience, out-of-body experience, and the mystical states produced by hallucinogenic drugs.