Seeking the Biology of Spirituality

With a brain scanner, a University of Pennsylvania scientist eavesdrops on the mind of a meditating Buddhist monk, sifting through the activity of neurons for evidence of spiritual grace.

Using skin sensors, a UC San Diego researcher measures the power of holy words by testing how synapses respond to religious texts.

A neuropsychiatrist at New York University assesses the effects of prayer. Another scientist measures brain function among those who report feelings of a union with God and the cosmos.

Marshaling high-speed medical imaging devices, radioactive tracers and new theories of mental activity, these researchers are probing the neurobiology of religious experience in search of a scientific perspective on the divine.

Where in the scientific cosmology of the mind does spiritual activity--the intangible essence of faith and moral sensibility--fit?

What are the physical foundations of metaphysical enlightenment, as embodied by Hindu samadhi, Zen satori, Sufi fana or the born-again experience of Pentecostal Christians?

Is there a biochemistry of belief?

“Does religion require a soul? Does science allow one?” asked UC San Diego theologian Michael J. McClymond, who recently organized a symposium to bring together neuroscientists and religious thinkers.

Such questions--long the province of theologians and philosophers--arise anew from a remarkable flowering in the study of the biology of behavior.

They reflect an upsurge of scientific interest in spirituality at a time when the largest percentage of Americans in a decade say they never doubt the existence of God, value daily prayer and believe in divine miracles.

However, such experiments also pose an unusual challenge to conventional religious thinking, so much so that the Vatican plans a conference in Poland in June to consider the implications of brain research.

“The issues are huge,” said Robert John Russell, director of the Center for Theology and Natural Science in Berkeley, which is convening its own meeting with the Templeton Foundation of scientists and religious leaders this spring.

“We cannot approach theology without some sense of the intricacy of the human brain,” said Michael A. Arbib, an expert on brain theory at the USC Center of Neural Engineering. New insights into brain function may challenge cherished religious precepts, he said. “A lot of what people hold as articles of faith are eroded by neuroscience.”

A number of theologians said they welcomed any scientific insights into spiritual practice, be it meditation, prayer, ritual behavior, or inspired visions of a higher plane of being.

But they also cautioned against any effort to reduce spiritual experience to biochemistry and neurons. Instead, several theologians said, the research is a tangible expression of the mind’s own remarkable struggle to know itself.

“If we recognize the brain does all the things that we [traditionally] attributed to the soul, then God must have some way of interacting with human brains,” said Nancey Murphy, a philosopher of science and religion at the Fuller Seminary in Pasadena.

Consequently, Murphy said, this new wave of research can be seen as an attempt to give “an account of divine action--one of the most difficult and pressing theological questions now--how God acts in the brain.”

*

Already there is evidence suggesting that the human brain may be naturally calibrated--by experience or by design--to spirituality.

Eventually, researchers pioneering such studies hope to approach questions that have challenged religious thinkers for centuries, from the neural nature of revelation to the changes in brain function that might accompany a religious conversion experience.

But the challenges of such research are enormous.

The range of religious and spiritual experience is so vast--from the intellectual discourse of a Talmudic scholar to the passionate rapture of someone speaking in tongues--that brain researchers are hard-pressed to frame scientific experiments that could address them. Until recently, there was little interest in funding such studies.

As a practical matter, moreover, the spirit is an elusive quarry.

“If someone has a spontaneous mystical experience, that is terrific, but it is hard to study in a laboratory,” said Andrew Newberg at the University of Pennsylvania, who is using single positron emission computed tomography (SPECT) to peer into minds in meditation.

Newberg and his colleagues chose to investigate the neurobiology of meditation precisely because it is a spiritual state easily duplicated in the laboratory. The study was funded by the Templeton Foundation, which is interested in fostering ties between science and religion.

Brains of Buddhist Monks Are Scanned

So far, they have scanned the brains of nine Buddhist monks during prolonged meditation. In the coming weeks, they plan to carry out a similar study of Catholic Franciscan nuns at prayer for comparison.

To photograph the neural activity during meditation, the researchers injected each monk with a faintly radioactive tracer chemical that quickly infuses into brain cells, where it illuminates neural activity for the SPECT camera.

The images reveal distinctive changes in brain activity as the mind settles into a meditative state, Newberg said.

In particular, activity diminished in those parts of the brain involved in generating a sense of three-dimensional orientation in space. The loss of one’s sense of place, in turn, could account for a spiritual feeling of release into a place beyond space and time.

This suggests that an essential element of the religious experience of transcendence may be hard-wired in the brain. Several experts said, however, that other factors like upbringing, belief and education could be just as important in influencing the brain’s sensitivity to a liturgical practice like meditation.

At UC San Diego’s Center for Brain and Cognition, V.S. Ramachandran has taken a more clinical approach.

A pioneer in experimental neurology, he studies patients with epilepsy, brain lesions, strokes or head injuries as a way of uncovering the fundamental architecture of the mind.

By testing patients who suffer seizures from temporal lobe epilepsy, his team found provocative hints of “dedicated neural machinery” that affects how intensely someone may respond to spiritual or mystical experiences.

As a side effect of their condition, these epileptics display an unusual obsession with religious matters and, during seizures, report overwhelming feelings of union with the universe. The researchers discovered that these people also have a heightened--completely involuntary--neural response to religious language.

“Something has happened in their temporal lobes that heightened their response to religious terms and icons,” Ramachandran said. “There may be a selective enhancement of emotions that are conducive to religious experience.”

He cautions that his work “does not prove” that brain mechanisms have evolved to respond to religion. Indeed, several brain researchers say that spirituality simply is too subjective an experience for any objective experiment.

Still, such research findings have prompted several religious thinkers to mull the possibility of something in the brain that may be naturally attuned to spiritual matters.

“I would not be surprised that there were parts of the brain that were involved in religious experience; otherwise it would not be clear why religious experience would be so distinct,” said Russell in Berkeley.

“But I don’t think religious experience or spirituality is a distinct category of neural activity. It is not just those parts of my brain twitching and nothing else.”

John Haught, a theologian at the Georgetown University Center for the Study of Science and Religion, said researchers have to resist the temptation to think that the mind and spirit can be fully specified and fully understood in terms of physical and chemical analysis.

New Discoveries Called ‘Wonderful’

The new findings are “wonderful knowledge,” Haught said.

“I admit something has to be there and functioning reliably in order for consciousness and spirituality to come about.” However, he said, “we can acknowledge the dependency of mind on body without that having to imply that mind is reducible to chemistry.”

Yet many leading brain researchers are prepared to claim just that.

They are confident that science will be able to explain everything about the higher functions of the human brain, including its capacity for spirituality and, by extension, religious belief.

Shaped by social experience and the action of genes, consciousness knits itself from the myriad threads of trillions of neural connections. So densely packed is brain tissue that a cubic millimeter contains almost four miles of neural wiring.

To many researchers, spirituality is just one of several powerful mental states generated by this unique network of interlaced neurons, synapses and glial cells.

“Mind has properties--self-consciousness, wonder, emotion and reason--that make it seem more than merely material,” said Arbib at USC.

“Yet I argue that all of this can be explained eventually by the physical properties of the brain. In 20 years, we will understand what happens in the brain when people have religious experiences.”

Even if scientists can explain the physical underpinnings of spiritual experiences, however, it is unlikely to settle the debate over what those experiences may mean or whether they signal an existence beyond the body.

*

The earliest physical token of humanity’s spiritual yearnings are traces of ancient pollen from hyacinth and hollyhock flowers--the remains of what many scholars believe was a garland placed by a mourner in a Neanderthal grave more than 44,000 years ago. Prehistoric cave paintings and rock carvings also attest to primordial mystical stirrings.

As a matter of evolutionary biology, there is only the most indirect evidence of how or when the physical brain developed a spiritual dimension.

In the process of evolution, each brain hemisphere developed its particular mode of perceiving, processing and experiencing information received through the senses.

The ability to form complex systems of belief may be linked to the brain’s prefrontal cortex, which appears responsible for the most sophisticated aspects of the human mind and its relationship with the world around it, said anthropologist and neuroscientist Marc D. Hauser at Harvard University.

“The crucial part of the brain is the part that has grown the largest in our evolutionary history. For linking up to something like religion and morality, the prefrontal cortex is critical,” Hauser said.

“Ours is about 200% larger than you would expect for a primate our size. It is absolutely immense.”

Human-Primate Gap Is Not Explained

Even so, that does not explain why there should be such a fundamental leap in mental ability between humans and other primates or why it should include a capacity for transcendental experience. Nor does it answer why some people should hear a spiritual call so clearly, while others seem effectively deaf to it.

Whatever the reason, most brain experts think that neurobiology some day will yield the ultimate answer.

“A modern neuroscientist has no need for the religious concept of a soul to explain the behavior of humans and other animals,” said Nobel laureate Francis Crick at the Salk Institute for Biological Studies in La Jolla. “Not all neuroscientists believe the concept of the soul is a myth, but certainly the majority do.

“A religious person would say there is no way you can explain what they experience in terms of what goes on inside their brain, that it must be their soul,” said Crick, who with James Watson discovered the structure of DNA, revealing how the inanimate chemical sequences of genes could give rise to living things.

“I think that is an open question.”

Indeed, for just that reason, laboratory investigations into the spiritual side of mental activity often raise hackles among those who see such research as an attack on religion.

There is a real risk, they say, that the effort to explain the biology underlying spiritual experience will simply reduce religious phenomena to a kind of unusual medical condition.

As a devout Lutheran and a neuropsychiatrist who studies prayer, Anglea Hegarty at NYU questions whether many researchers can objectively assess spiritual experience. “Most of my colleagues basically see religion as a sort of pathological state,” she said. “That is terrible thinking.”

Yet how else are clinicians to diagnose the subjective experience of an ecstatic vision, of disembodied voices or of direct personal communication with another plane of being?

“There are bits and pieces about neural activity that can give clues to what might be happening in normal religious experience without implying that normal religious experience is an illness,” said UCLA psychiatrist Leslie A. Brothers, who has been working for the past year with the organizers of the Vatican conference.

“The real issue is whether there will be room for a divine being once we can explain the phenomenon of subjective experience through neural mechanisms or social mechanisms.”

*

In one sense, the debate over the biology of spiritual experience reflects an argument over human significance that dates to the Renaissance, when astronomers discovered that the Earth is not the center of the physical universe. Darwin’s 19th-century insights into evolution further diminished mankind’s sense of primacy.

Today, people are wrestling with new frontiers in the meaning of life. Molecular biologists mapping the human genome have reduced life to its inanimate chemical sequences. Further, scientists seek, in the action of genes, the origins of virtue, altruism and moral behavior.

Humanity’s Claim to Uniqueness

For better or worse, neuroscience is encroaching on what some consider humanity’s last hold on uniqueness.

Moreover, new scientific ideas about the nature of mental activity, which appear to be at odds with some Judeo-Christian beliefs, are well within the mainstream of Buddhist, Hindu or Islamic thought.

One’s sense of a separate self may be simply a tenuous mental construct--as evidenced by many brain studies--and that echoes Hindu and Buddhist beliefs about the illusion of the material world, Ramachandran at UC San Diego said.

“The sense of the self being aloof from the rest of creation--that is indeed an illusion,” he said. “You can do clinical experiments to show this is true.”

In the end, however, it is more likely that the emerging insights of neuroscience will help shape theology of the next century, just as underlying precepts of Western philosophy and religious thought have helped steer past scientific endeavor, several experts said.

Only six years ago, the Vatican formally apologized for finding Galileo guilty of heresy in 1663 for insisting that the Earth orbits the sun. More recently, Pope John Paul II acknowledged that evolution may be more than a hypothesis.

In the same way, scientific insights into mental activity eventually may be incorporated into church doctrines and precepts of belief, some researchers maintain.

“My task as a neuroscientist is to help theologians gain respect for the wonderful subtleties of the brain,” said Arbib.

“Perhaps what we share is a question, even though we may disagree on the fundamental answer.”

(BEGIN TEXT OF INFOBOX / INFOGRAPHIC)

Tuning in to Spirituality

University of Pennsylvania researchers watched how mental activity changes during meditation by scanning the brains of Buddhist monks with single positron emission computed tomography.

The images show that mental activity during meditation diminished in the parietal lobe and the frontal lobe compared to baseline images taken when the monks were just resting.

Those parts of the brain help the mind orient itself. The loss of one’s sense of place, in turn, could account for a transcendent feeling of release into a place beyond space and time.

Source: Andrew Newberg, University of Pennsylvania Medical Center