Brain Re-Wiring

[sanjuro_ronin]

Kind of an old article from Time, but something that shows the value of meditation and visualization training:

How The Brain Rewires Itself

By Sharon Begley

It was a fairly modest experiment, as these things go, with volunteers
trooping into the lab at Harvard Medical School to learn and practice a
little five-finger piano exercise. Neuroscientist Alvaro Pascual-Leone
instructed the members of one group to play as fluidly as they could,
trying to keep to the metronome's 60 beats per minute. Every day for
five days, the volunteers practiced for two hours. Then they took a test.

At the end of each day's practice session, they sat beneath a coil of
wire that sent a brief magnetic pulse into the motor cortex of their
brain, located in a strip running from the crown of the head toward each
ear. The so-called transcranial-magnetic-stimulation (TMS) test allows
scientists to infer the function of neurons just beneath the coil. In
the piano players, the TMS mapped how much of the motor cortex
controlled the finger movements needed for the piano exercise. What the
scientists found was that after a week of practice, the stretch of motor
cortex devoted to these finger movements took over surrounding areas
like dandelions on a suburban lawn.

The finding was in line with a growing number of discoveries at the time
showing that greater use of a particular muscle causes the brain to
devote more cortical real estate to it. But Pascual-Leone did not stop
there. He extended the experiment by having another group of volunteers
merely think about practicing the piano exercise. They played the simple
piece of music in their head, holding their hands still while imagining
how they would move their fingers. Then they too sat beneath the TMS coil.

When the scientists compared the TMS data on the two groups--those who
actually tickled the ivories and those who only imagined doing so--they
glimpsed a revolutionary idea about the brain: the ability of mere
thought to alter the physical structure and function of our gray matter.
For what the TMS revealed was that the region of motor cortex that
controls the piano-playing fingers also expanded in the brains of
volunteers who imagined playing the music--just as it had in those who
actually played it.

"Mental practice resulted in a similar reorganization" of the brain,
Pascual-Leone later wrote. If his results hold for other forms of
movement (and there is no reason to think they don't), then mentally
practicing a golf swing or a forward pass or a swimming turn could lead
to mastery with less physical practice. Even more profound, the
discovery showed that mental training had the power to change the
physical structure of the brain.

OVERTHROWING THE DOGMA

FOR DECADES, THE PREVAILING DOGMA IN neuroscience was that the adult
human brain is essentially immutable, hardwired, fixed in form and
function, so that by the time we reach adulthood we are pretty much
stuck with what we have. Yes, it can create (and lose) synapses, the
connections between neurons that encode memories and learning. And it
can suffer injury and degeneration. But this view held that if genes and
development dictate that one cluster of neurons will process signals
from the eye and another cluster will move the fingers of the right
hand, then they'll do that and nothing else until the day you die. There
was good reason for lavishly illustrated brain books to show the
function, size and location of the brain's structures in permanent ink.

The doctrine of the unchanging human brain has had profound
ramifications. For one thing, it lowered expectations about the value of
rehabilitation for adults who had suffered brain damage from a stroke or
about the possibility of fixing the pathological wiring that underlies
psychiatric diseases. And it implied that other brain-based fixities,
such as the happiness set point that, according to a growing body of
research, a person returns to after the deepest tragedy or the greatest
joy, are nearly unalterable.

But research in the past few years has overthrown the dogma. In its
place has come the realization that the adult brain retains impressive
powers of "neuroplasticity"--the ability to change its structure and
function in response to experience. These aren't minor tweaks either.
Something as basic as the function of the visual or auditory cortex can
change as a result of a person's experience of becoming deaf or blind at
a young age. Even when the brain suffers a trauma late in life, it can
rezone itself like a city in a frenzy of urban renewal. If a stroke
knocks out, say, the neighborhood of motor cortex that moves the right
arm, a new technique called constraint-induced movement therapy can coax
next-door regions to take over the function of the damaged area. The
brain can be rewired.

The first discoveries of neuroplasticity came from studies of how
changes in the messages the brain receives through the senses can alter
its structure and function. When no transmissions arrive from the eyes
in someone who has been blind from a young age, for instance, the visual
cortex can learn to hear or feel or even support verbal memory. When
signals from the skin or muscles bombard the motor cortex or the
somatosensory cortex (which processes touch), the brain expands the area
that is wired to move, say, the fingers. In this sense, the very
structure of our brain--the relative size of different regions, the
strength of connections between them, even their functions--reflects the
lives we have led. Like sand on a beach, the brain bears the footprints
of the decisions we have made, the skills we have learned, the actions
we have taken.

[sanjuro_ronin]

Same article:

SCRATCHING A PHANTOM LIMB

AN EXTREME EXAMPLE OF HOW CHANGES IN the input reaching the brain can
alter its structure is the silence that falls over the somatosensory
cortex after its owner has lost a limb. Soon after a car crash took
Victor Quintero's left arm from just above the elbow, he told
neuroscientist V.S. Ramachandran of the University of California at San
Diego that he could still feel the missing arm. Ramachandran decided to
investigate. He had Victor sit still with his eyes closed and lightly
brushed the teenager's left cheek with a cotton swab.

Where do you feel that? Ramachandran asked. On his left cheek, Victor
answered--and the back of his missing hand. Ramachandran stroked another
spot on the cheek. Where do you feel that? On his absent thumb, Victor
replied. Ramachandran touched the skin between Victor's nose and mouth.
His missing index finger was being brushed, Victor said. A spot just
below Victor's left nostril caused the boy to feel a tingling on his
left pinkie. And when Victor felt an itch in his phantom hand,
scratching his lower face relieved the itch. In people who have lost a
limb, Ramachandran concluded, the brain reorganizes: the strip of cortex
that processes input from the face takes over the area that originally
received input from a now missing hand. That's why touching Victor's
face caused brain to "feel" his missing hand.

Similarly, because the regions of cortex that handle sensations from the
feet abut those that process sensations from the surface of the
genitals, some people who have lost a leg report feeling phantom
sensations during sex. Ramachandran's was the first report of a living
being knowingly experiencing the results of his brain rewiring.

THINKING ABOUT THINKING

AS SCIENTISTS PROBE the limits of neuroplasticity, they are finding that
mind sculpting can occur even without input from the outside world. The
brain can change as a result of the thoughts we think, as with
Pascual-Leone's virtual piano players. This has important implications
for health: something as seemingly insubstantial as a thought can affect
the very stuff of the brain, altering neuronal connections in a way that
can treat mental illness or, perhaps, lead to a greater capacity for
empathy and compassion. It may even dial up the supposedly immovable
happiness set point.

In a series of experiments, for instance, Jeffrey Schwartz and
colleagues at the University of California, Los Angeles, found that
cognitive behavior therapy (CBT) can quiet activity in the circuit that
underlies obsessive-compulsive disorder (OCD), just as drugs do.
Schwartz had become intrigued with the therapeutic potential of
mindfulness meditation, the Buddhist practice of observing one's inner
experiences as if they were happening to someone else.

When OCD patients were plagued by an obsessive thought, Schwartz
instructed them to think, "My brain is generating another obsessive
thought. Don't I know it is just some garbage thrown up by a faulty
circuit?" After 10 weeks of mindfulness-based therapy, 12 out of 18
patients improved significantly. Before-and-after brain scans showed
that activity in the orbital frontal cortex, the core of the OCD
circuit, had fallen dramatically and in exactly the way that drugs
effective against OCD affect the brain. Schwartz called it
"self-directed neuroplasticity," concluding that "the mind can change
the brain."

The same is true when cognitive techniques are used to treat depression.
Scientists at the University of Toronto had 14 depressed adults undergo
CBT, which teaches patients to view their own thoughts differently--to
see a failed date, for instance, not as proof that "I will never be
loved" but as a minor thing that didn't work out. Thirteen other
patients received paroxetine (the generic form of the antidepressant
Paxil). All experienced comparable improvement after treatment. Then the
scientists scanned the patients' brains. "Our hypothesis was, if you do
well with treatment, your brain will have changed in the same way no
matter which treatment you received," said Toronto's Zindel Segal.

But no. Depressed brains responded differently to the two kinds of
treatment--and in a very interesting way. CBT muted overactivity in the
frontal cortex, the seat of reasoning, logic and higher thought as well
as of endless rumination about that disastrous date. Paroxetine, by
contrast, raised activity there. On the other hand, CBT raised activity
in the hippocampus of the limbic system, the brain's emotion center.
Paroxetine lowered activity there. As Toronto's Helen Mayberg explains,
"Cognitive therapy targets the cortex, the thinking brain, reshaping how
you process information and changing your thinking pattern. It decreases
rumination, and trains the brain to adopt different thinking circuits."
As with Schwartz's OCD patients, thinking had changed a pattern of
activity--in this case, a pattern associated with depression--in the brain.

HAPPINESS AND MEDITATION

COULD THINKING ABOUT THOUGHTS IN A new way affect not only such
pathological brain states as OCD and depression but also normal
activity? To find out, neuroscientist Richard Davidson of the University
of Wisconsin at Madison turned to Buddhist monks, the Olympic athletes
of mental training. Some monks have spent more than 10,000 hours of
their lives in meditation. Earlier in Davidson's career, he had found
that activity greater in the left prefrontal cortex than in the right
correlates with a higher baseline level of contentment. The relative
left/right activity came to be seen as a marker for the happiness set
point, since people tend to return to this level no matter whether they
win the lottery or lose their spouse. If mental training can alter
activity characteristic of OCD and depression, might meditation or other
forms of mental training, Davidson wondered, produce changes that
underlie enduring happiness and other positive emotions? "That's the
hypothesis," he says, "that we can think of emotions, moods and states
such as compassion as trainable mental skills."

With the help and encouragement of the Dalai Lama, Davidson recruited
Buddhist monks to go to Madison and meditate inside his functional
magnetic resonance imaging (fMRI) tube while he measured their brain
activity during various mental states. For comparison, he used
undergraduates who had had no experience with meditation but got a crash
course in the basic techniques. During the generation of pure
compassion, a standard Buddhist meditation technique, brain regions that
keep track of what is self and what is other became quieter, the fMRI
showed, as if the subjects--experienced meditators as well as
novices--opened their minds and hearts to others.

More interesting were the differences between the so-called adepts and
the novices. In the former, there was significantly greater activation
in a brain network linked to empathy and maternal love. Connections from
the frontal regions, so active during compassion meditation, to the
brain's emotional regions seemed to become stronger with more years of
meditation practice, as if the brain had forged more robust connections
between thinking and feeling.

But perhaps the most striking difference was in an area in the left
prefrontal cortex--the site of activity that marks happiness. While the
monks were generating feelings of compassion, activity in the left
prefrontal swamped activity in the right prefrontal (associated with
negative moods) to a degree never before seen from purely mental
activity. By contrast, the undergraduate controls showed no such
differences between the left and right prefrontal cortex. This suggests,
says Davidson, that the positive state is a skill that can be trained.

For the monks as well as the patients with depression or OCD, the
conscious act of thinking about their thoughts in a particular way
rearranged the brain. The discovery of neuroplasticity, in particular
the power of the mind to change the brain, is still too new for
scientists, let alone the rest of us, to grasp its full meaning. But
even as it offers new therapies for illnesses of the mind, it promises
something more fundamental: a new understanding of what it means to be
human.

[sanjuro_ronin]

For centuries, visualization was used in meditation, recently, sports has come to value the substancial benefit of visualization.

A case of "everything old is new again", perhaps ?