Neural pathways to enlightenment

Stephen Pincock
December 8, 2006

Researchers are exploring the science behind mystical experiences.

They're among the most personal and mysterious sensations we might encounter - a vision of blinding light as death draws near, the ecstasy of prayer or meditation or the sensation of floating outside our own bodies.

For millenniums, people have given these experiences religious significance. But in recent years, scientists have begun exploring this spiritual realm, asking their own questions about what goes on in our brains during these extraordinary events and coming up with some fascinating answers.

In laboratories around the world, a few specialists have had their own insights into the neurology of spiritual experiences, using precise techniques to stimulate and monitor the brain's function.

These new studies delve into questions that have long fascinated scientists, says John Watson, a neurologist at the University of Sydney.

"Neuroscientists are now doing bolder and bolder things," Watson says. "We've already seen studies into the neurology of things like love, thirst and hunger, so it wasn't a big step for them to start wondering about these religious and quasi-religious experiences."

Some people call this new field "neurotheology", a term coined by Aldous Huxley in his 1962 novel Island. Scientists often refer to it as the cognitive neuroscience of religious experience and spirituality.

In 1997, researchers from the University of California in San Diego announced there might be dedicated neural machinery in the brain's temporal lobes specifically linked with religion. Vilayanur Ramachandran and his team studied the brains of people with an unusual type of epilepsy that affects the brain's temporal lobes.

People who suffer this kind of seizure often report having intense mystical and religious experiences as part of their attacks. The researchers found that one effect of the seizures was to strengthen the involuntary response of the patient's brain to religious words.

It wasn't long before these regions were being referred to by newspapers as the "God spot" or "God module" - areas of the brain that become electrically excited when people think about their deity.

Most scientists, including Ramachandran, regard the idea of a single "God spot" as too simplistic. Last September, for example, a Canadian researcher, Mario Beauregard, and his student Vincent Paquette used a technique called functional magnetic resonance imaging (fMRI) to study the brain activity of Carmelite nuns while they were reliving the experience of unio mystica, an intense sensation in which they feel the physical presence of God.

With this imaging, researchers monitor changes in blood flow in the brain almost in real time, allowing them to see which regions of the brain become more or less active under different conditions.

Beauregard reported that the nuns' ecstatic state was associated with a distinct pattern of activity in several brain areas. The results suggest, according to the researchers, that "mystical experiences are mediated by several brain regions and systems" - not just one.

Meanwhile, other researchers have probed the experiences of people with temporal lobe epilepsy with more interesting results. In Switzerland, for example, a neurologist, Olaf Blanke, and his colleagues found that electrically stimulating specific brain regions can trigger repeated out-of-body experiences.

Roughly one person in 10 has this kind of experience, but rigorous study was rare until a few years ago when Blanke came across a case in a 43-year-old woman he was also testing and treating for epilepsy.

On that occasion, the experience was triggered when a part of her brain near the junction point of the temporal and parietal lobes was stimulated with an electrode. Every time that part of her brain was stimulated, the woman described "floating above her own body and watching herself".

Blanke's colleague Shahar Arzy has suggested the junction between the temporal and parietal lobes also may have played a part in some of the central events in world religions.

As Arzy and his co-authors pointed out in an article two years ago, many of the world's religions feature revelation experiences that take place on mountains. Meanwhile, acutely non-mystic mountaineers have similar experiences regularly too. Long stays at high altitudes may affect the brain, he says, and "facilitate the experience of a revelation".

He suggests a few mechanisms that could be involved. Crucially, lack of oxygen can affect the temporoparietal junction and long stays at high altitudes, especially in solitude, might lead to low resistance to stress and loss of inhibition.

These same issues might even have played a part in one of the most famous mystical phenomena of ancient times - the oracle of Delphi - researchers suggested in October.

George Papatheodorou, an emeritus professor of geology at Patras University, and his colleagues were examining the narrow cave where the Delphic priestesses were believed to have delivered their messages. They found high levels of methane, ethanol and carbon dioxide in the cave's air.

"The site lies on a fault where gases leak out. These gases cause an oxygen reduction that induces a mild hypnotic state that could well produce hallucinations," Papatheodorou told the Greek Kathimerini newspaper.

At a laboratory at the University of Kentucky in Lexington, another researcher is exploring one of the most powerful spiritual phenomena of all, the near-death experience.

Neurophysiologist Kevin Nelson believes these experiences may be dream-like states triggered by stress and a common sleep disorder known as sleep paralysis.

As people with this condition begin to wake, part of their brain stays in the random eye movement (REM) phase of sleep. They find themselves unable to move and experience frightening hallucinations.

Nelson studied 55 people who had near-death experiences in a range of circumstances, including heart attacks, traffic accidents and fainting and found that about 60 per cent reported symptoms of sleep paralysis.

In a matched group of 55 healthy volunteers, only 24 per cent had those symptoms.

Nelson and his colleagues reported in April that "these findings anticipate that under circumstances of peril, a near-death experience is more likely in those with previous REM intrusion".

The evidence is preliminary and the same could be said for much of the research into spiritual neurology, but that does not make it any less fascinating. "The philosophical question we're really asking is 'can the brain understand the brain?' " Watson says.

Beauregard reported that the nuns' ecstatic state was associated with a distinct pattern of activity in several brain areas. The results suggest, according to the researchers, that "mystical experiences are mediated by several brain regions and systems" - not just one.

Meanwhile, other researchers have probed the experiences of people with temporal lobe epilepsy with more interesting results. In Switzerland, for example, a neurologist, Olaf Blanke, and his colleagues found that electrically stimulating specific brain regions can trigger repeated out-of-body experiences.

Roughly one person in 10 has this kind of experience, but rigorous study was rare until a few years ago when Blanke came across a case in a 43-year-old woman he was also testing and treating for epilepsy.

On that occasion, the experience was triggered when a part of her brain near the junction point of the temporal and parietal lobes was stimulated with an electrode. Every time that part of her brain was stimulated, the woman described "floating above her own body and watching herself".

Blanke's colleague Shahar Arzy has suggested the junction between the temporal and parietal lobes also may have played a part in some of the central events in world religions.

As Arzy and his co-authors pointed out in an article two years ago, many of the world's religions feature revelation experiences that take place on mountains. Meanwhile, acutely non-mystic mountaineers have similar experiences regularly too. Long stays at high altitudes may affect the brain, he says, and "facilitate the experience of a revelation".

He suggests a few mechanisms that could be involved. Crucially, lack of oxygen can affect the temporoparietal junction and long stays at high altitudes, especially in solitude, might lead to low resistance to stress and loss of inhibition.

These same issues might even have played a part in one of the most famous mystical phenomena of ancient times - the oracle of Delphi - researchers suggested in October.

George Papatheodorou, an emeritus professor of geology at Patras University, and his colleagues were examining the narrow cave where the Delphic priestesses were believed to have delivered their messages. They found high levels of methane, ethanol and carbon dioxide in the cave's air.

At a laboratory at the University of Kentucky in Lexington, another researcher is exploring one of the most powerful spiritual phenomena of all, the near-death experience.

Neurophysiologist Kevin Nelson believes these experiences may be dream-like states triggered by stress and a common sleep disorder known as sleep paralysis.

As people with this condition begin to wake, part of their brain stays in the random eye movement (REM) phase of sleep. They find themselves unable to move and experience frightening hallucinations.

Nelson studied 55 people who had near-death experiences in a range of circumstances, including heart attacks, traffic accidents and fainting and found that about 60 per cent reported symptoms of sleep paralysis.

In a matched group of 55 healthy volunteers, only 24 per cent had those symptoms.

Nelson and his colleagues reported in April that "these findings anticipate that under circumstances of peril, a near-death experience is more likely in those with previous REM intrusion".

The evidence is preliminary and the same could be said for much of the research into spiritual neurology, but that does not make it any less fascinating. "The philosophical question we're really asking is 'can the brain understand the brain?' " Watson says.