Science's biggest mystery

By RICH HEFFERN

A baffling and profound mystery lies at the heart of one of the fastest-growing research areas in science today.

The mystery is human consciousness and how -- or even whether -- it arises out of our fleshy brains.

How does it happen that billions of nerve cells collaborate in an organ no bigger than half a football, allowing us not only to navigate intricate math equations and entertain elaborate thoughts, but to observe ourselves as we perform such functions, to feel exquisite emotions that a computer couldn’t begin to comprehend?

It is a fascinating field of study that is luring some of the nation’s best and brightest scientists, including some with a religious bent. They are drawn because they know that the explanation, when it comes, will be as stunningly mind-boggling as the discovery of DNA or the development of quantum physics. And -- because it stands to potentially overthrow the reigning scientific assumption that everything has a material explanation -- it could unite science and religion in a way no discovery has before.

Scientists know a lot about the brain’s structure and functions, yet know next to nothing about the process that leads to the clear sense of identity that emerges from our experiences and to our richly diverse inner lives.

Consciousness is not simply the opposite of unconsciousness. It involves a definite sense that someone is in the driver’s seat, an executive “I” who constantly monitors input from the senses, from inner states, from emotions, from the environment, then orders behavior and speech with access to both a memory library and an imagination.

It is comprised of our sense of identity, location and time, of our perceptions of the world around us, the memories that lace our stories and beliefs about the world, our emotional states and inclinations, our capacity to direct perceptions and thoughts, our sense of well-being, our zest for life, and much more. Consciousness is the brain’s overall awareness of the competing claims of all that information at any given time.

The quest to understand it has captured the imaginations of cognitive neuroscientists, psychologists and philosophers, who tend to line up on either side of a classic matter-spirit divide.

Those holding to the “materialist” view contend that the overwhelming evidence points to consciousness as a product of the inert gray matter in our skulls and nothing more. Harvard psychologist Steven Pinker asserts that “the supposedly immaterial soul we now know can be bisected with a knife, altered by chemicals, started or stopped by electricity, and extinguished by a sharp blow or by insufficient oxygen.”

But there’s another group willing to consider an alternative view, one found in many spiritual traditions: that consciousness arises from something beyond the material world; that it is conceivably a key component of the cosmos, as fundamental as space, time and matter.

As answers are found, they may bridge the gap in scientific worldviews. But for now, both groups agree that ethical and religious questions abound in the area of consciousness research. “Questions once confined to theological speculations and late-night dorm room bull sessions are now at the forefront,” Pinker says.

At what point does a fetus acquire consciousness? Could we “raise” a mind like pioneers raised a barn, by building a sufficiently intricate machine? Is a cat’s mind quantitatively or qualitatively different from ours? What kind of consciousness exists in the partly fused brains of a pair of Siamese twins? When the physiological activity of the brain finally ceases, does that executive “I” go entirely out of existence?

Pinker describes the current state of research: “With some problems a modicum of consensus has taken shape. With others, the puzzlement is so deep that they may never be resolved. Some of our deepest convictions about what it means to be human have been shaken. It shouldn’t be surprising that research on consciousness is alternately exhilarating and disturbing. No other topic is like it.”

Cognitive neuroscientists agree that it’s a field that still awaits its Einstein or its Francis Crick, the co-discoverer of DNA. In fact, Crick himself was working in the area of cognitive neuroscience until he died in 2004.

Woven on an enchanted loom

The physical building blocks of the mind are neurons, highly specialized, electrically excitable nerve cells down which voltage travels. Those currents are sent down the axon, a long stalk for transmitting the information over distance. At the axon’s tip are tree-like branching dendrites receiving signals from other neurons. The information jumps between the neurons across synapses by means of chemical transmitters.

The result is a rich tapestry woven together moment by moment on the brain’s enchanted loom. It cannot be located in one specific area of that organ, scientists say. It’s distributed over many parts and perhaps beyond.

How far beyond is the elusive question.

Is consciousness simply what the brain -- an organized, folded clump of billions of those neurons -- produces? Is it just one more biological phenomenon like the digestive process? Our kidneys produce urine; our brains produce thoughts, feelings and an inner life.

Or is the mind animated from outside by some supernatural vapor or wonder principle we as yet know nothing about?

It is also the famous mind-body problem that philosophers from Aristotle through Descartes, Kant, Liebniz and Berkeley have debated for thousands of years. How exactly do two entities as apparently different as body and mind interact?

Our seemingly ethereal minds have physical effects. You feel hungry. Your mind suggests possibilities. Then your legs and arms work in concert to get you off the couch to go make sandwiches in the kitchen.

Meanwhile the body can affect the mind. Chemical neurotransmitters gone awry cause the hallucinations of schizophrenia. Severe pain can drive every other thought out of your head.

In the view of many scientists and philosophers, conscious states, while produced by lower-level neurobiological processes, are themselves higher-level features of the brain.

John Searle, professor of philosophy at the University of California, Berkeley, explains: “In nature there are numerous instances where a higher- level feature of a system is caused by its lower-level elements. Think of water’s liquidity or the transparency of glass. You can’t reach into a glass of water, pick out a molecule and say, ‘This is wet.’ Yet wetness pervades.”

“Just so,” he adds, “one cannot point to a single neuron in the brain and say ‘this one is thinking about my grandmother.’ As far as we know anything about it, thoughts about grandmothers occur at a much higher level than that of the single neuron, just as liquidity occurs at a much higher level than that of a single molecule of hydrogen or oxygen.”

In the materialist’s world, there is no need to separate “physical” and “mental.” The brain’s biological processes cause consciousness but the consciousness that arises there is not some extra entity.

Free will, or the robust sense we have of human agency directing our affairs, is an illusion, the materialists hold. We are just “meat puppets” reacting to physical states that are pre-determined solely by genes, upbringing and biological activity responding to outside input.

As Pinker puts it, “We wouldn’t find someone guilty of murder if his finger pulled the trigger when it was mechanically connected to a roulette wheel; why should it be any different if the roulette wheel is inside his skull?”

Biologist Crick called this “the astonishing hypothesis,” the idea that “our ideas, sensations, joys, aches and sorrows arise entirely out of physiological activity in the meaty folds of the physical brain, and nothing more.” This is as good a summary as any of the materialist position.

A gap that is an abyss

Among those who find the materialist explanations wanting is one of the foremost researchers in cognitive science, David J. Chalmers, a philosopher at the Australian National University. He divides its exploration, arguing that each phenomenon of mind requires examination, but believes some will be easier to describe than others.

Examples of the “easy” problems include accounting for how memory or attention really work, how we react to outside stimuli, how the mind interacts with the body to get us around in the world; the ability of the mind to access the body’s inner states, such as the need for sleep or food; the difference between wakefulness and sleep. Chalmers believes that in each case an appropriate physiological model can do the explanatory work.

The really “hard” problem is the problem of experience, the subjective aspect of consciousness, the executive “I” and its amazingly private nature.

“Why should physical processing give rise to a rich and private inner life at all?” asks Chalmers. “It’s a mystery.”

The science of consciousness is just beginning what Chalmers calls its “correlation” stage, where scientists systematically find this area of the brain goes with that discrete aspect of mind, this brain process correlates with this color perception or ability to access a memory, and so on. The process is made possible by new brain imaging technologies such as functional magnetic resonance imaging (fMRI) and positron emission tomography (PET).

In moving beyond such basic correlations to an overall explanation, “we’re still wholly in the dark,” Chalmers says.

Some researchers offer recent discoveries in quantum physics as an explanation of mind. “Consciousness is a strange, mysterious subject, and it’s possible it will take some strange, mysterious force to explain it,” Chalmers says. “But using quantum physics is still a materialist explanation. It doesn’t account for the wide explanatory gap between the ‘easy’ and the ‘hard’ problems.”

Even if every single behavioral and cognitive function were explained, he says, there would still remain a further mystery: “Why is the performance of these functions accompanied by conscious experience?”

Even a detailed knowledge of neural workings and the physical correlates of consciousness may fail to explain in the end how or why humans have self-aware minds that can create epic poems and grand operas, make up puns and jokes or launch intuitive leaps of the imagination.

It’s easy to imagine a “zombie,” Chalmers says, a creature physically identical to a human, functioning in all the right ways, having conversations, playing chess, but simply lacking all conscious experience. So if a person can be physically identical to us yet without consciousness, then it would seem that consciousness is not a physical thing.

“There is an explanatory gap here that is really something of an abyss,” says Chalmers.

He surmises that a solution to the hard problem will probably take two or three big breakthroughs. “In understanding life and genetics, for example, it took some profound conceptual revolutions to get to the bottom of the problem there. Nobody expected the breakthrough in biology that was the discovery of DNA.”

The same process will happen with consciousness, he says. It will take some creative neuroscientists to break through, and it will probably take decades for this to play out.

At bottom, Chalmers suspects some hitherto unknown physical quality of the universe might be involved, some component of the universe such as time or gravity, not derivable from or reducible to anything else.

Beyond the brain

New challenges to materialism in neuroscience such as Chalmers’ come at a time when private sources of money are emerging to support investigations into areas where religion and science touch. The John Templeton Foundation, a philanthropic organization run by the financier’s evangelical son, John M. Templeton Jr., spent $36 million last year promoting efforts to bridge the gap between science and religion, including funding for some consciousness studies. The Mind and Life Institute, in Louisville, Colo., has been providing funds for experiments and conferences that explore the mental activities of Tibetan Buddhist meditators.

That sort of investigation makes sense to researchers such as Andrew Newberg, professor of psychiatry at the University of Pennsylvania, who boldly question the materialist presumption. “Is consciousness perhaps something that exists out there beyond the brain, as many religious traditions like Buddhism and Hinduism might consider?” Newberg asks.

Other scientists posing similarly heretical questions include Jeffrey M. Schwartz, a research professor of psychiatry at the University of California at Los Angeles. Schwartz has been treating people with obsessive-compulsive disorders to counter their urges through focused attention of the mind. Scans of his patients’ brains reveal that such mental therapy can alter the behavior of their brains, something that could not happen if the mind emerged entirely from the brain, he says.

These scientists openly wonder whether consciousness has an immaterial aspect, perhaps related to what theologians have traditionally called the soul.

Stephen F. Heinemann, president of the Society for Neuroscience and a professor in the molecular neurobiology lab at the Salk Institute for Biological Studies in La Jolla, Calif., echoes many scientists’ reactions to such nonmaterialist speculation when he says, “I think the concept of the mind outside the brain is absurd.”

Mario Beauregard, coauthor of The Spiritual Brain: How Neuroscience Is Revealing the Existence of God and associate professor in the departments of radiology and psychology at the University of Montreal, regards human free will, an important concept in religion and theology, as a serious obstacle to the materialist explanation of human consciousness.

The problem for materialists, according to Beauregard, is that the subjective experience of free will necessitates an agent that can sometimes completely override that alleged biological predetermination, or “the roulette wheel’s spin.”

A bystander selflessly jumps into a freezing river to save survivors of an airplane crash. That overriding agency cannot be explained in purely materialist terms.

He finds further evidence for a non-materialist explanation of consciousness in widespread reports on the medical placebo effect, and in accounts of near-death experiences.

His own research with Carmelite nuns in Montreal, using magnetic resonance imaging and quantitative electroencephalography to learn more about brain activity during a prayer experience, showed that neuroscience can provide useful information about religious experiences.

“Contemplation produces brain states not associated with ordinary consciousness, and the signatures left behind in the brain by such experiences indicate that the experiencer contacts a reality outside herself.”

Beauregard says that the hard problem ceases to be a problem once we understand the universe itself as the realm of consciousness that was there from the beginning.

“We might expect living beings to evolve toward mind if consciousness underlies the universe. Consciousness study in the 21st century promises to be an exciting endeavor but it will be stymied if the only purpose is to reduce consciousness to something it is not or to show it’s an illusion,” Beauregard says.

He is not the only scientist suggesting that the very foundations of modern science are being undermined by consciousness research.

John Haught, Senior Fellow in Science and Religion at the Woodstock Theological Center at Georgetown University in Washington, told NCR: “After the philosopher Descartes’ famous formulation, ‘I think, therefore I am,’ mind and matter were separated in such a way that modern science and philosophy don’t see subjectivity or mind as really a part of the universe.”

Haught recognizes that, for hard-nosed materialists, bridging the explanatory gap necessarily involves a sort of alchemy, or magic. To get the richness of our consciousness to somehow emerge out of nothing more than primordial dust and primeval rocks for the materialists is like pulling a rabbit out of a hat. “The qualitative feel of consciousness, each person’s unshakable private experience, is a deeply puzzling phenomenon for them,” he said.

Haught’s view is that consciousness, or mind, was there from the beginning; human consciousness developed over an evolutionary course that has taken billions of years.

“This more aptly fits both the Christian Trinitarian approach and our Catholic sacramental and biblical views,” Haught said, adding that the universe, the Earth, evolution and the Christian scriptures are all about promise.

“Theologically I link that sense of promise to the presence of the divine that permeates the universe from the very beginning into the future.”

Mind research aligns the whole of nature with us, in our status of anticipating union with God, he said. “Surprisingly, the study of consciousness or mind thoroughly re-values the natural world, and we desperately need that today.”

While answers remain elusive, one thing is sure: Scientists and philosophers will continue to probe deeply into this territory, seeking to understand how the breathtaking range of our human experience, imagination, creativity and faith arise out of three pounds of wet, electrified meat encased within our skulls.

Rich Heffern is an NCR staff writer. His e-mail address is rheffern@ncronline.org.

National Catholic Reporter, February 8, 2008