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  Just Relax
Photo of Alan being monitored for stress

Herbert Benson measures Alan's stress.

Quick! What is 6,046 minus 13? Don't know? Well, that's okay. We were just trying to stress you out, like we did to Alan in Herbert Benson's lab at the Mind/Body Medical Institute in Boston. In "Just Relax," Benson and his colleagues stress out Alan's mind while gauging his body's reaction, expressed via his skin conductance (sweatiness) and muscle tension.

Once Alan is suitably riled up, he's then guided through what Benson has dubbed the "relaxation response." Benson has long been an advocate of the potential health benefits provided by relaxation. First he asks Alan to close his eyes and relax all his muscles, from head to toe. Then Alan has to focus on his breathing while at the same time silently repeating the mantra, "calm" to himself. It's a simple form of meditation. Alan responds well and reports feeling both more relaxed and, mysteriously, warmer. He's not the only one. In 1981 Benson led expeditions to study Tibetan monks who practice Tum-mo yoga as part of their spiritual practice. Benson documented the monks' ability to raise the temperature of their extremities as much as 15 degrees, simply by using their minds.

Photo of a woman meditating
Why does Meditation feel relaxing?  

How can meditation have such an impact on the body? To find out, psychologist Sara Lazar is looking into Hari Mandir Kaur Khalsa's brain. Khalsa, an expert in Kundalini yoga, is able to meditate while inside a MRI machine. First, Lazar asks Khalsa to think randomly, to see what a brain that's not meditating looks like. In this trial, her breathing rate is a normal 12 breaths per minute.

Next Lazar asks Khalsa to start meditating. Her breathing rate falls off dramatically-to about 4 breaths per minute--and a region of the brain called the amygdala becomes active. Researchers used to think meditation was a bit like falling asleep, so Lazar's discovery that it activates the amygdala, which is associated with vigilance, is a surprise. The discovery does match the heightened awareness that Khalsa herself reports during meditation, however. It also sheds some light on how meditation reduces stress, since the amygdala is involved in controlling the fight or flight stress response. But researchers still don't know how meditators can change such responses seemingly at will.

For more on this topic, see the web feature:
Relaxation 101
Running for the Shelter

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