By Daniel Strain, Science News
If a tree falls on you in the forest while you're meditating, does it still hurt?
Well, yes. But maybe not quite as much as it would if you weren't meditating, researchers from North Carolina and Wisconsin report in the April 6 Journal of Neuroscience. Individuals who practiced mindfulness meditation, or samatha, during a pain experiment reported much less discomfort than they did in earlier, meditation-free sessions. Samatha, the team says, flipped switches on or off in diverse regions of the brain underlying attention, expectation and even the awareness of thoughts themselves.
Getting hit by a tree limb will hurt, but it won't hurt everyone in the same way, says study coauthor Robert Coghill, a neuroscientist at the Wake Forest University School of Medicine in Winston-Salem, N.C. The conscious mind, which is informed by personal experience and context, is an expert at deciding which sensations to take note of and which to ignore. "All the time we're hanging out, our brain is being bombarded with all sorts of information," he says. "But we let it go." A falling tree is more jarring than the tickle of a forearm hair, but meditation may help people to similarly let "ouch!" and "yowza!" reflexes go.
In the study, Coghill and his colleagues prodded 15 volunteers with a hot poker of sorts, then used MRI to watch their brains respond to the hot but humane torture. Subjects found the 49 degree Celsius pulses, on average, 57 percent less unpleasant and 40 percent less intense while meditating as opposed to resting normally.
Study coauthor Fadel Zeidan, himself a meditation practitioner for over a decade, taught the newbie subjects mindfulness meditation. In just four 20-minute sessions, the dilettantes got a crash course in how to focus their attention on their breathing without becoming derailed by sore bottoms or anxious thoughts.
Meditation, often associated with tranquility, in fact lights up parts of the brain like a Christmas tree. The anterior insula, for instance, which lies in a deep fold on the side of the brain and has been associated with sensing heat, cold and pain, shined bright in the meditation experiments. This region may also preside over the awareness of thoughts themselves, says Zeidan, a cognitive neuroscientist also at Wake Forest. If you've ever suppressed the desire to honk your horn rudely in traffic, you may have your anterior insula to thank. "The meditators were able to take a step back from their thoughts and look at them for what they were," he says.
Parts of the thalamus, on the other hand, flicked off during meditation. The thalamus filters the endless trains of sensory signals arriving to the brain from the body. Meditation could, then, ensure that fewer ouch-inducing signals reach the conscious mind in the first place.
This study illustrates what a powerful pain reliever psychology can be, says Donald Price, who researches pain and the placebo effect at the University of Florida in Gainesville. In some cases, changing a patient's outlook on pain can be just as soothing as certain doses of morphine. But, he admits, most doctors and nurses don't have the time to turn the lights down low and lead meditation sessions.
Rolling meditation into the hospital setting will take time, suggests Susan Smalley, director of the Mindful Awareness Research Center at UCLA. Few studies, including this one, have looked at the health impacts of meditation using controlled, clinical-style studies. Still, she hopes it's only a matter of time before meditation becomes a regular activity for most Americans. Few people, she notes, wore seat belts when they first came on the market. "Now everyone wears them," she says. "I kind of think mindfulness and practices like that are at that early stage."