Meanwhile, Richard Davidson, professor of psychology and psychiatry at the University of Wisconsin School of Medicine and Public Health, has been using the same technique to study the neurological effect of meditation. Participants in his study ranged from meditation newcomers to Tibetan monks with 54,000 hours of meditation experience.
Those brain scans also showed an increase in activity in the prefrontal cortex, which is — among its many functions — involved in the control and regulation of attention. The Wisconsin researchers, who published their work in a recent issue of the Proceedings of the National Academy of Sciences, even resorted to a little psychological warfare to see whether they could distract the attention of the participants. It wasn't hard to derail the newcomers, because meditation isn't as easy as it sounds, but the monks had no trouble at all.
"Most people, if they heard a baby screaming, would have some emotional response," Davidson said. But the monks remained nonplussed. "They do hear the sound — we can detect that in the auditory cortex— but they don't have the emotional reaction." In other words, less amygdala, more prefrontal cortex, the same result that the UCLA researchers found.
Davidson's research grew out of a scientific relationship with the Dalai Lama, spiritual leader of Tibetan Buddhists, and he has studied them for 15 years.
Lieberman hopes that the research will eventually lead to a more enlightened approach to treating patients with severe emotional problems. If the amygdala, for example, is running out of control, there's little chance that the prefrontal cortex will be able to correct the course. And if the prefrontal cortex isn't up to the task, "talk therapy isn't going to work because the machine doesn't work right," he said.
Of course, it isn't practical to give every patient a brain scan to see whether medication, or therapy, is the right course.
"It would be ridiculous to have somebody get a $1,000 scan to see if they should be getting $80 therapy," Lieberman said.
"The hope is that in five or 10 years we'll have some simple tasks, and have patients do a simple emotional task," to determine whether the problem lies in the amygdala or in the prefrontal cortex, he said. "That would be a very cheap instrument for health providers."
Lee Dye is a former science writer for the Los Angeles Times. He now lives in Juneau, Alaska.