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Sunday, August 5, 2012

Meditation found to increase brain size By William J. Cromie

Meditation found to increase brain size 
Mental calisthenics bulk up some layers 
By William J. Cromie
Harvard News Office
Harvard University Gazette
February 2, 2006 
Sara Lazar (center) talks to research assistant Michael Treadway and
technologist Shruthi Chakrapami about the results of experiments
showing that meditation can increase brain size. (Staff photo Kris
Snibbe/Harvard News Office) 
People who meditate grow bigger brains than those who don't.
Researchers at Harvard, Yale, and the Massachusetts Institute of
Technology have found the first evidence that meditation can alter
the physical structure of our brains. Brain scans they conducted
reveal that experienced meditators boasted increased thickness in
parts of the brain that deal with attention and processing sensory
In one area of gray matter, the thickening turns out to be more
pronounced in older than in younger people. That's intriguing because
those sections of the human cortex, or thinking cap, normally get
thinner as we age. 
"Our data suggest that meditation practice can promote cortical
plasticity in adults in areas important for cognitive and emotional
processing and well-being," says Sara Lazar, leader of the study and
a psychologist at Harvard Medical School. "These findings are
consistent with other studies that demonstrated increased thickness
of music areas in the brains of musicians, and visual and motor areas
in the brains of jugglers. In other words, the structure of an adult
brain can change in response to repeated practice." 
The researchers compared brain scans of 20 experienced meditators
with those of 15 nonmeditators. Four of the former taught meditation
or yoga, but they were not monks living in seclusion. The rest worked
in careers such as law, health care, and journalism. All the
participants were white. During scanning, the meditators meditated;
the others just relaxed and thought about whatever they wanted. 
Meditators did Buddhist "insight meditation," which focuses on
whatever is there, like noise or body sensations. It doesn't involve
"om," other mantras, or chanting. 
"The goal is to pay attention to sensory experience, rather than to
your thoughts about the sensory experience," Lazar explains. "For
example, if you suddenly hear a noise, you just listen to it rather
than thinking about it. If your leg falls asleep, you just notice the
physical sensations. If nothing is there, you pay attention to your
breathing." Successful meditators get used to not thinking or
elaborating things in their mind. 
Study participants meditated an average of about 40 minutes a day.
Some had been doing it for only a year, others for decades. Depth of
the meditation was measured by the slowing of breathing rates. Those
most deeply involved in the meditation showed the greatest changes in
brain structure. "This strongly suggests," Lazar concludes, "that the
differences in brain structure were caused by the meditation, rather
than that differences in brain thickness got them into meditation in
the first place." 
Lazar took up meditation about 10 years ago and now practices insight
meditation about three times a week. At first she was not sure it
would work. But "I have definitely experienced beneficial changes,"
she says. "It reduces stress [and] increases my clarity of thought
and my tolerance for staying focused in difficult situations." 
Controlling random thoughts 
Insight meditation can be practiced anytime, anywhere. "People who do
it quickly realize that much of what goes on in their heads involves
random thoughts that often have little substance," Lazar comments.
"The goal is not so much to 'empty' your head, but to not get caught
up in random thoughts that pop into consciousness." 
She uses this example: Facing an important deadline, people tend to
worry about what will happen if they miss it, or if the end product
will be good enough to suit the boss. You can drive yourself crazy
with unproductive "what if" worry. "If, instead, you focus on the
present moment, on what needs to be done and what is happening right
now, then much of the feeling of stress goes away," Lazar says.
"Feelings become less obstructive and more motivational." 
The increased thickness of gray matter is not very much, 4 to 8
thousandths of an inch. "These increases are proportional to the time
a person has been meditating during their lives," Lazar notes. "This
suggests that the thickness differences are acquired through
extensive practice and not simply due to differences between
meditators and nonmeditators." 
As small as they are, you can bet those differences are going to lead
to lots more studies to find out just what is going on and how
meditation might better be used to improve health and well-being, and
even slow aging. 
More basic questions need to be answered. What causes the increased
thickness? Does meditation produce more connections between brain
cells, or more blood vessels? How does increased brain thickness
influence daily behavior? Does it promote increased communication
between intellectual and emotional areas of the brain? 
To get answers, larger studies are planned at Massachusetts General
Hospital, the Harvard-affiliated facility where Lazar is a research
scientist and where these first studies were done. That work included
only 20 meditators and their brains were scanned only once. 
"The results were very encouraging," Lazar remarks. "But further
research needs to be done using a larger number of people and testing
them multiple times. We also need to examine their brains both before
and after learning to meditate. Our group is currently planning to do
this. Eventually, such research should reveal more about the function
of the thickening; that is, how it affects emotions and knowing in
terms of both awareness and judgment." 
Slowing aging? 
Since this type of meditation counteracts the natural thinning of the
thinking surface of the brain, could it play a role in slowing - even
reversing - aging? That could really be mind-boggling in the most
positive sense. 
Lazar is cautious in her answer. "Our data suggest that one small bit
of brain appears to have a slower rate of cortical thinning, so
meditation may help slow some aspects of cognitive aging," she
agrees. "But it's important to remember that monks and yogis suffer
from the same ailments as the rest of us. They get old and die, too.
However, they do claim to enjoy an increased capacity for attention
and memory." 

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