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Meditation Gives Brain a Charge, Study Finds
By Marc Kaufman
Washington Post Staff Writer
Monday, January 3, 2005; Page A05
Brain research is beginning to produce concrete evidence for something that
Buddhist practitioners of meditation have maintained for centuries: Mental
discipline and meditative practice can change the workings of the brain and
allow people to achieve different levels of awareness.
Those transformed states have traditionally been understood in transcendent
terms, as something outside the world of physical measurement and objective
evaluation. But over the past few years, researchers at the University of
Wisconsin working with Tibetan monks have been able to translate those
mental experiences into the scientific language of high-frequency gamma
waves and brain synchrony, or coordination. And they have pinpointed the
left prefrontal cortex, an area just behind the left forehead, as the place
where brain activity associated with meditation is especially intense.
"What we found is that the longtime practitioners showed brain activation on
a scale we have never seen before," said Richard Davidson, a neuroscientist
at the university's new $10 million W.M. Keck Laboratory for Functional
Brain Imaging and Behavior. "Their mental practice is having an effect on
the brain in the same way golf or tennis practice will enhance performance."
It demonstrates, he said, that the brain is capable of being trained and
physically modified in ways few people can imagine.
Scientists used to believe the opposite -- that connections among brain
nerve cells were fixed early in life and did not change in adulthood. But
that assumption was disproved over the past decade with the help of advances
in brain imaging and other techniques, and in its place, scientists have
embraced the concept of ongoing brain development and "neuroplasticity."
Davidson says his newest results from the meditation study, published in the
Proceedings of the National Academy of Sciences in November, take the
concept of neuroplasticity a step further by showing that mental training
through meditation (and presumably other disciplines) can itself change the
inner workings and circuitry of the brain.
The new findings are the result of a long, if unlikely, collaboration
between Davidson and Tibet's Dalai Lama, the world's best-known practitioner
of Buddhism. The Dalai Lama first invited Davidson to his home in
Dharamsala, India, in 1992 after learning about Davidson's innovative
research into the neuroscience of emotions. The Tibetans have a
centuries-old tradition of intensive meditation and, from the start, the
Dalai Lama was interested in having Davidson scientifically explore the
workings of his monks' meditating minds. Three years ago, the Dalai Lama
spent two days visiting Davidson's lab.
The Dalai Lama ultimately dispatched eight of his most accomplished
practitioners to Davidson's lab to have them hooked up for
electroencephalograph (EEG) testing and brain scanning. The Buddhist
practitioners in the experiment had undergone training in the Tibetan
Nyingmapa and Kagyupa traditions of meditation for an estimated 10,000 to
50,000 hours, over time periods of 15 to 40 years. As a control, 10 student
volunteers with no previous meditation experience were also tested after one
week of training.
The monks and volunteers were fitted with a net of 256 electrical sensors
and asked to meditate for short periods. Thinking and other mental activity
are known to produce slight, but detectable, bursts of electrical activity
as large groupings of neurons send messages to each other, and that's what
the sensors picked up. Davidson was especially interested in measuring gamma
waves, some of the highest-frequency and most important electrical brain
impulses.
Both groups were asked to meditate, specifically on unconditional
compassion. Buddhist teaching describes that state, which is at the heart of
the Dalai Lama's teaching, as the "unrestricted readiness and availability
to help living beings." The researchers chose that focus because it does not
require concentrating on particular objects, memories or images, and
cultivates instead a transformed state of being.
Davidson said that the results unambiguously showed that meditation
activated the trained minds of the monks in significantly different ways
from those of the volunteers. Most important, the electrodes picked up much
greater activation of fast-moving and unusually powerful gamma waves in the
monks, and found that the movement of the waves through the brain was far
better organized and coordinated than in the students. The meditation
novices showed only a slight increase in gamma wave activity while
meditating, but some of the monks produced gamma wave activity more powerful
than any previously reported in a healthy person, Davidson said.
The monks who had spent the most years meditating had the highest levels of
gamma waves, he added. This "dose response" -- where higher levels of a drug
or activity have greater effect than lower levels -- is what researchers
look for to assess cause and effect.
In previous studies, mental activities such as focus, memory, learning and
consciousness were associated with the kind of enhanced neural coordination
found in the monks. The intense gamma waves found in the monks have also
been associated with knitting together disparate brain circuits, and so are
connected to higher mental activity and heightened awareness, as well.
Davidson's research is consistent with his earlier work that pinpointed the
left prefrontal cortex as a brain region associated with happiness and
positive thoughts and emotions. Using functional magnetic resonance
imagining (fMRI) on the meditating monks, Davidson found that their brain
activity -- as measured by the EEG -- was especially high in this area.
Davidson concludes from the research that meditation not only changes the
workings of the brain in the short term, but also quite possibly produces
permanent changes. That finding, he said, is based on the fact that the
monks had considerably more gamma wave activity than the control group even
before they started meditating. A researcher at the University of
Massachusetts, Jon Kabat-Zinn, came to a similar conclusion several years
ago.
Researchers at Harvard and Princeton universities are now testing some of
the same monks on different aspects of their meditation practice: their
ability to visualize images and control their thinking. Davidson is also
planning further research.
"What we found is that the trained mind, or brain, is physically different
from the untrained one," he said. In time, "we'll be able to better
understand the potential importance of this kind of mental training and
increase the likelihood that it will be taken seriously."
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