THURSDAY, Feb. 19, 2004 (HealthDayNews) -- It turns out that when Bill Clinton uttered those immortal words, "I feel your pain," he may well have.
Researchers in Britain have shown that feeling empathy for another person's pain actually does activate some, if not all, of the emotional circuitry in the human brain.
The findings appear in the Feb. 20 issue of Science, along with additional research showing, for the first time, that the placebo effect also involves changes in the brain.
"There have been doubts over the years about whether [the placebo effect] is a physiological reality or whether people are simply reporting the benefits of treatment because they want the physician to be pleased," says study co-author Dr. Kenneth L. Casey, a neurology consultant at Ann Arbor VA Health Care System in Michigan.
"We were able to demonstrate that the pain pathways in the brain show reduced activity during the placebo effect, which can be interpreted to mean that they are actually are experiencing less pain," he adds.
Both studies relied on advanced imaging technology to prove their points.
Empathy refers to the ability to feel what others feel and is part of the glue that holds together relationships and societies.
According to the study authors, empathy may have two evolutionary functions: to create attachments between mother and child and later between mates and to help people predict the actions of others.
Until now, however, there has been very little research into how the brain actually responds to empathy.
Tania Singer, lead author of the empathy study, and her colleagues decided to use functional magnetic resonance imaging (fMRI) to look at the brain activity of volunteers who experienced a direct painful stimulus (electrode to the hand) and then observed a loved one experiencing the same painful stimulus.
Sixteen couples were asked to come to the lab. While the female partner lay in the scanner, her partner sat in a chair next to the scanner. Both had electrodes attached to their right hands, which delivered short painful or non-painful stimulation. Both partners could see their own electrodes and those on their partner.
The researchers were mainly interested in the differences in brain function when the woman was experiencing the pain directly and when she was witnessing her partner feel pain.
As it turned out, only part of the pain matrix was activated when feeling empathy for others. It appears the affective section was activated, while the sensory component was not.
Empathy was activated by an emotional cue, such as a facial expression, and also by a less personal cue, such as an arrow indicating whether the pulse was painful or not.
"One question was whether this whole big network was involved, and what we found is that it's only the emotionally affective section and not the sensory section," Singer says.
In other words, the partner feeling empathy did not feel the actual bee sting of the electrode on the right hand (the sensory component). "That is about the source of the pain, where it comes from," Singer explains. "This information only lights up when you actually have pain."
They did, however, feel emotion at the sight of their partner in pain. "That is what we call the affective component," Singer says.
There were also different degrees of empathy, indicated by differing levels of brain activity. "Women who scored high on empathy questionnaires had higher brain activity in empathy-related areas," Singer says.
These findings open up many possibilities. Next, Singer plans to try to answer the question of whether people have any control over their empathy.
"This has implications for medical personnel or therapists who can't automatically feel the pain of others because they would be rushed at the end of the day," Singer says.
There are also implications for sociopaths and others who show particular cruelty towards groups of people.
While sociopaths may be "hard-wired" not to feel, other individuals may be inhibiting their empathy.
The new knowledge of the placebo effect may help researchers come up with new treatments for chronic or acute pain, the study authors say. It also reinforces the need for the physician to portray a treatment in a positive light. If the patient expects that it will work, he or she may then reap at least some benefit.