We’ve historically tended to separate mental and spiritual processes from biological processes. We had no choice. Scientific technology that could examine body parts and functions couldn’t observe the biology of thought and belief. Philosophers and theologians thus explored a disembodied mind and soul, and biologists focused on body systems.

Mind and brain merged during the second half of the 20th century, as scientists gradually discovered brain correlates for such mental functions as learning/memory, logic/reason, decision/behavior, and even emotion (an especially difficult system to understand). Still, scientists couldn’t explain the neurobiology of our subjective response to such simple sensory qualities as a blue sky or a gentle breeze (commonly called qualia), so how could they ever explain the biology of the more complex subjective and transcendent elements of thought and belief? Well, they could try.

Brain imaging technology became more powerful during the last decade of the 20th century, and scientists used it to seek solutions to the deeper mysteries of consciousness, the Holy Grail of the neurosciences. At the turn of the century, world-renowned neuroscientists Antonio Damasio (1999) and Nobel Laureate Gerald Edelman (2000) published separate but related acclaimed theories of the neurobiology of consciousness. The 21st century thus began with an ascendant Biology. Biologists completed the Genome Project – an explanation of the objective nature of life, and they also discovered the neurobiology of consciousness – an explanation of the subjective meaning of life.

Andrew Newberg holds a joint appointment in the Medical School and Department of Religion, and (the late) Eugene D’Aquili was in the Department of Psychiatry at the University of Pennsylvania. Their extended research focused on the search for the underlying biology of religious belief and mystical experiences. Brain imaging technology allowed them to probe into areas that had long eluded exploration, and they’ve now published their discoveries in an intriguing, thoughtprovoking, non-technical book, Why God Won’t Go Away: Brain Science and the Biology of Belief (2001).

Since they realized that the book’s focus would appeal to many with a very limited background in the neurosciences, they tended to describe brain systems and processes in functional rather than in technical terms. The book reads easily (probably partly because science writer Vince Rause helped to write the book).

The book contains commentary that will both delight and irritate just about every reader. The authors focus on the basic question: Why do religion and spirituality continue to thrive in an era of unprecedented scientific and technological enlightenment? Their answer is that religion and spirituality are a natural outcome of the way our brain is organized to respond to the dangers and opportunities it confronts, and so they consider religion and spirituality to be biologically real and not trivial foolish phenomena.

All religions arise from and are maintained by transcendent experiences, so the authors explored the underlying neurobiology of myth, ritual, and mysticism, which are central to religious practice. Their research led them to reject the belief that these arose out of cultural drives to maintain social cohesiveness. Rather, they are deeply rooted in the manner in which specific brain systems respond to internal and external stimuli. Further, since myth, ritual, and mysticism are driven by neurobiology, it’s not surprising that they exhibit striking similarities across all religions.

An especially intriguing discovery emerged out of brain imaging studies that Newberg and D’Aquili conducted with meditating Tibetan Buddhists and praying Franciscan nuns. The research focused on regions of the parietal lobes (in the top rear section of our brain) that orient us in and allow us to navigate through physical space. The left hemisphere segment of this system processes our inner sense of self, and the right hemisphere segment processes our outer sense of the surrounding environment. So this is our brain’s self/non-self system, an important component of consciousness.

They discovered that both hemispheric segments are normally quite active, but that they (and especially the left hemisphere/self segment) exhibit a marked decrease in neuronal activity during peak transcendent periods. In effect, the self/non-self system loses its ability to locate the mental border between self and the surrounding world — and so it perceives the biological reality of an endless self that’s at one with all creation, a merging with God. Transcendence thus meets biology.

The chapters on myth, ritual, mysticism, and religion first discuss their intriguing nature and cultural significance, and then explain how the relevant brain systems functionally combine to process the phenomenon — and in the process, to move cognition into a transcendent level. It’s a good literary device in that it helps readers with a limited understanding of the cognitive neurosciences to easily comprehend what is otherwise pretty complex biology.

Newberg and D’Aquili have written a well-researched, thoughtful, balanced, accessible book on an important issue. It’s a book that couldn’t have been written earlier, but expect more developments in this emerging field of neurotheology. The book will stimulate both religious and non-religious readers, and religious professionals will discover much in it that they can effectively use in their work.