Tuesday, November 15, 2005
MEDITATORS HAVE THICKER BRAINS
CanWest News Service
Monday, November 14, 2005
People who meditate have thicker brains, according to scientists who believe they have found the first structural evidence the popular mental exercise may increase grey matter.
Using magnetic resonance imaging, or MRI, Boston researchers found that parts of the brain important for attention and sensory processing, meaning how we take in and make sense of things, were thicker in meditators.
While all were extensively experienced in Buddhist Insight meditation, "these are normal people with jobs and families" who meditated, on average, 40 minutes per day, said Dr. Jeremy Gray, assistant professor of psychology at Yale University and co-author of the study. "You don't have to be a monk to see these changes in the actual structure of the brain."
The sample size was small, just 35 people. So were the differences in brain thickness.
"It's not like they grew a new chunk of the brain," Gray said. "These were not huge differences but they were statistically significant. The exciting part was that there was any difference at all."
Supported by the U.S. National Institutes of Health, the MIND Institute and the U.S. Centers for Disease Control and Prevention, the research is published in the journal, NeuroReport. It was presented Sunday at the Society for Neuroscience meeting in Washington, D.C.
Earlier research has found Transcendental Meditation lowers blood pressure, reduces cholesterol and hardening of the arteries. A study published in May in the American Journal of Cardiology found Transcendental Meditation reduces death rates by 23 per cent.
People who meditate report less stress, and scientists have linked long-term stress to shrinking of the part of the brain involved in memory and learning. By contrast, meditation might promote brain "plasticity" -- meaning its ability to be moulded or shaped. Studies, mostly in Buddhist monks, have found meditation changes brain activity as measured by an EEG.
The Boston scientists hypothesized that it might change the brain's actual physical structure, too.
Led by Dr. Sara Lazar, of the Psychiatric Neuroimaging Research Program at Massachusetts General Hospital, the researchers measured cortical thickness in 20 people trained in Buddhist Insight meditation, a popular form of the mental exercise that doesn't use mantra or chanting, but rather focuses on "mindfulness", being aware of sensations, feelings and state of mind.
The average age was 38 and people had, on average, nine years of meditation experience. Two were full-time mediation teachers.
They were matched by age, gender and education to 15 people who had never meditated or done yoga. MRI studies found parts of the cerebral cortex, the outer layer of the brain, were thicker in those who meditated.
Buddha says; "A mind which is not protected by mindfulness is as helpless as a blind man walking over uneven ground without a guide."