new pain research

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February 20, 2004 Los Angeles Times/THE NATION

Studies Suggest the Mind Makes, Breaks Its Misery Brain research

indicates that people are hard-wired for empathy, and that faith affects

the experience of their own agony and that of others.

By Lee Hotz, Times Staff Writer

Pain, like beauty, is in the mind's eye.It is altered by empathy and

tempered by faith, three new brain-imaging studies suggest.

The bewitching effect of belief can alter directly how strongly people

feel pain, causing measurable changes in brain cells and synapses

whether the torment is theirs or

a loved one's.

The new findings, made public today by independent research teams at the

University

of Michigan, Princeton University, UCLA, and University College London,

offer the

strongest evidence yet of how the brain thinks about pain.

Mapping the neural anatomy of pain, the researchers documented the ways

in which the brain created a world of its own from the raw material of

physical sensation.

Using medical imaging scanners to monitor brain activity, researchers at

Michigan, UCLA and Princeton revealed that simple faith in a placebo

could alter the neural circuits that process pain, easing the agony.

In a separate experiment, the researchers at University College showed

that the brain was a mirror of suffering, reflecting through many of the

same neural circuits the pain that others feel, much as if the sensation

were its own genuine torment.

Indeed, the brain's ability to share another's response to pain at such

a fundamental cellular level may be the key to a sense of empathy, the

personality trait that underpins so many human relationships,

researchers said.

" These brain regions are critical to the interplay between the outside

world and you, " said neuropsychologist Helen Mayberg at Emory University

in Atlanta.

By directly monitoring mental activity, the researchers showed how

expectations and anticipation molded the brain's response to the

physical sensation of pain. To a certain degree, pain is an act of

imagination.

" We are zeroing in on some pathways where our thoughts and beliefs are

changing our physical and emotional experience, " UCLA psychologist

Lieberman said. " We don't typically think of those as things we

can control. "

Each team used brain mapping techniques to survey the same neural

terrain from three slightly different perspectives.

Two of the studies were published today in the journal Science. The

third will be published next month in Neuroimaging.

To better understand pain and empathy, a team led by social psychologist

Tania Singer at the Institute of Neurology at University College tested

19 couples who, because they were romantically involved, could be

expected to be attuned to each other.

One woman from each pair was monitored with a functional magnetic

resonance imaging scanner. Her neural activity was recorded first as

researchers gave her a brief electric shock, then as her partner

received the same shock. The researchers discovered that the same

critical brain regions involved in processing the physical sensation of

pain were activated in each case.

Feelings of empathy for another's pain triggered regions of the brain

responsible for processing pain, much as if it were a direct sensation,

researchers discovered.

To Singer and her colleagues, it strongly suggested that humans were

hard-wired for empathy. " We are pretty sure that it is a universal

mechanism, " Singer said. " It is how we can put ourselves emotionally in

another's shoes. "

To investigate how belief affects the brain's response to pain,

Lieberman and his UCLA colleagues conducted brain scans of 14 patients

given a placebo to treat their chronic abdominal pain.

The experiment revealed that the patients' faith in the substance they

were given eased their symptoms and also produced physical changes in

areas of the brain that processed pain.

The greater the brain changes, the greater the reduction in pain, the

researchers determined.

At Michigan and Princeton, researchers produced even more compelling

evidence that the expectation of relief caused physical changes in how

the brain handled pain. They tested dozens of volunteers by giving them

shocks while monitoring their neural activity in a brain scanner.

Then researchers gave all the volunteers a placebo in the form of a

harmless cream the patients were told would prevent the pain. Then the

scientists conducted another round of shocks.

The expectation of relief was enough to cause physical changes in those

pain-processing areas of the brain, offering evidence of the placebo

effect. " We actually see physical changes in the brain that correspond

closely to changes in symptoms that the patients report, " said

psychologist Tor Wager, who led the Michigan research team.

The researchers determined that pain depended not only on the actual

sensory signals from nerves that the brain received but also on a

person's emotional state.