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Thursday, December 15, 2011

Meditation found to increase brain size

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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