The Brain That Changes Itself:
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Recently
I wrote a book about the revolutionary
discovery that the human brain can
change itself, as told through the
stories of the scientists, doctors, and
patients who have together brought about
these astonishing transformations.
Without operations or medications, they
have made use of the brain's hitherto
unknown ability to change.
Some were patients who had what were thought to be incurable brain problems; others were people without specific problems who simply wanted to improve the functioning of their brains or preserve them as they aged. For four hundred years this venture would have been inconceivable because mainstream medicine and science believed that brain anatomy was fixed. The common wisdom was that after childhood the brain changed only when it began the long process of decline; that when brain cells failed to develop properly, or were injured, or died, they could not be replaced. Nor could the brain ever alter its structure and find a new way to function if part of it was damaged.
The theory of the unchanging
brain decreed that people who were born
with brain or mental limitations, or who
sustained brain damage, would be limited
or damaged for life. Scientists who
wondered if the healthy brain might be
improved or preserved through activity
or mental exercise were told not to
waste their time. A neurological
nihilism -- a sense that treatment for
many brain problems was ineffective or
even unwarranted -- had taken hold, and
it spread through our culture, even
stunting our overall view of human
nature. Since the brain could not
change, human nature, which emerges from
it, seemed necessarily fixed and
unalterable as well.
The belief that the brain could not
change had three major sources: the fact
that brain-damaged patients could so
rarely make full recoveries; our
inability to observe the living brain's
microscopic activities; and the idea --
dating back to the beginnings of modern
science -- that the brain is like a
glorious machine. And while machines do
many extraordinary things, they don't
change and grow.
I became interested in the idea of a
changing brain because of my work as a
research psychiatrist and psychoanalyst.
When patients did not progress
psychologically as much as hoped, often
the conventional medical wisdom was that
their problems were deeply "hardwired"
into an unchangeable brain. "Hardwiring"
was another machine metaphor coming from
the idea of the brain as computer
hardware, with permanently connected
circuits, each designed to perform a
specific, unchangeable function.
When I first heard news that the human
brain might not be hardwired, I had to
investigate and weigh the evidence for
myself. These investigations took me far
from my consulting room.
I began a series of travels, and in the
process I met a band of brilliant
scientists, at the frontiers of brain
science, who had, in the late 1960s or
early 1970s, made a series of unexpected
discoveries. They showed that the brain
changed its very structure with each
different activity it performed,
perfecting its circuits so it was better
suited to the task at hand. If certain
"parts" failed, then other parts could
sometimes take over. The machine
metaphor, of the brain as an organ with
specialized parts, could not fully
account for changes the scientists were
seeing. They began to call this
fundamental brain property "neuroplasticity."
Neuro is for "neuron," the nerve cells
in our brains and nervous systems.
Plastic is for "changeable, malleable,
modifiable." At first many of the
scientists didn't dare use the word "neuroplasticity"
in their publications, and their peers
belittled them for promoting a fanciful
notion. Yet they persisted, slowly
overturning the doctrine of the
unchanging brain. They showed that
children are not always stuck with the
mental abilities they are born with;
that the damaged brain can often
reorganize itself so that when one part
fails, another can often substitute;
that if brain cells die, they can at
times be replaced; that many "circuits"
and even basic reflexes that we think
are hardwired are not. One of these
scientists even showed that thinking,
learning, and acting can turn our genes
on or off, thus shaping our brain
anatomy and our behavior -- surely one
of the most extraordinary discoveries of
the twentieth century.
In the course of my travels I met a
scientist who enabled people who had
been blind since birth to begin to see,
another who enabled the deaf to hear; I
spoke with people who had had strokes
decades before and had been declared
incurable, who were helped to recover
with neuroplastic treatments; I met
people whose learning disorders were
cured and whose IQs were raised; I saw
evidence that it is possible for
eighty-year-olds to sharpen their
memories to function the way they did
when they were fifty-five. I saw people
rewire their brains with their thoughts,
to cure previously incurable obsessions
and traumas. I spoke with Nobel
laureates who were hotly debating how we
must rethink our model of the brain now
that we know it is ever changing.
The idea that the brain can change its
own structure and function through
thought and activity is, I believe, the
most important alteration in our view of
the brain since we first sketched out
its basic anatomy and the workings of
its basic component, the neuron. Like
all revolutions, this one will have
profound effects. The neuroplastic
revolution has implications for, among
other things, our understanding of how
love, sex, grief, relationships,
learning, addictions, culture,
technology, and psychotherapies change
our brains. All of the humanities,
social sciences, and physical sciences,
insofar as they deal with human nature,
are affected, as are all forms of
training. All of these disciplines will
have to come to terms with the fact of
the self-changing brain and with the
realization that the architecture of the
brain differs from one person to the
next and that it changes in the course
of our individual lives.
While the human brain has apparently
underestimated itself, neuroplasticity
isn't all good news; it renders our
brains not only more resourceful but
also more vulnerable to outside
influences. Neuroplasticity has the
power to produce more flexible but also
more rigid behaviors -- a phenomenon I
call "the plastic paradox." Ironically,
some of our most stubborn habits and
disorders are products of our
plasticity. Once a particular plastic
change occurs in the brain and becomes
well established, it can prevent other
changes from occurring. It is by
understanding both the positive and
negative effects of plasticity that we
can truly understand the extent of human
possibilities.
from the book The Brain That Changes
Itself by Norman Doidge, M.D.
Published
by Penguin; December
2007;$16.00US/$27.50CAN;
978-0-14-311310-2
Copyright © 2008 Norman Doidge, M.D.
About The
Author:
Norman Doidge, M.D., is a psychiatrist,
psychoanalyst, and researcher on the
faculty at the Columbia University
Center for Psychoanalytic Training and
Research in New York and the University
of Toronto's department of psychiatry,
as well as an author, essayist, and
poet. He is a four-time recipient of
Canada's National Magazine Gold Award.
He divides his time between Toronto and
New York. His book, The Brain That
Changes Itself
is available at all
booksellers.
Visit the author's Web site at
www.normandoidge.com.

