EXCERPT - Part 1
Welcome to the Age of the Miracle Brain
Popular Myth: You are born with a genetically determined
brain of a certain size and potential, and that's it. There's
little or no way to alter its capabilities and functioning; thus,
your chances in life are predestined, your fate sealed.
New Scientific Reality: The brain is a growing, changing
organ, its capabilities and vitality dependent to a large degree
on how you nourish and treat it. Thus, you can dramatically influence
your brain's functioning and your own destiny. The long neglected
brain is now being exposed to intense biological scrutiny, and
the news is good for all of us.
Good-bye, "Brain as Machine"
In every century, philosophers, scientists, clergy, and scholars
put their particular spin on the nature of the brain. In the
mid 1700s, a British philosopher described the brain as "an
ingenious system of vibrating hollow tubes," similar to
a church organ. In the industrial age, the appropriate metaphor
is brain as machine, currently that ultimate information processor,
the computer--hardwired, forged of immutable metal and chips
to be programmed, with a preordained memory and capacity.
But new brain discoveries render
the metaphor unsuitable. If the demands on your computer outstrip
its capabilities, it becomes junk. It does not grow a few more
chips, nor rev up its inner byte resources to improve memory
or performance. No, its physical structure is decreed forever
by circumstances of its birth in some computer factory. You can
kick it, pour nutrients over it, make it listen to music, give
it smart drugs, but it does not get smarter. Not so with a real,
living brain.
The notion of brain as computer
or machine is a relic of yesterday's science. Exciting new investigations
of the brain show it to be a growing, ever-changing massive complexity
of cells, a miraculous living organ malleable by external and
internal influences. Just as the structure and function of the
heart changes-improving or deteriorating-in response to diet,
drugs, and exercise, so do those of the brain.
Neuroscientists now know the
brain is an organ of mind-boggling plasticity--like the rest
of your body, dynamic, not "fixed" for life. Larry
Squire, professor of neuroscience at the University of California
at San Diego and past president of the national Society for Neuroscience,
has said: "If you could use a video camera to watch the
brain respond to experiences, I have no doubt you would see it
growing, retracting, reshaping."
"The most important thing
is to realize that the brain is growing and changing all the
time," agrees leading brain researcher Bruce McEwen at New
York's Rockefeller University.
"The chemical composition
of the neurons themselves is changing, and hence there is no
separate and unchanging hardware, in contrast to a programmable
range of software. "
-- Susan Greenfield,
The Human Brain: A Guided Tour, 1997
Until recently, we have known
little about the biological architecture of the brain compared
with other organs, such as the liver, kidney, and heart. Why?
Very simple, says British neurologist Richard S.J. Frackowiak
at London's Institute of Neurology, in a fascinating article
in Daedalus, published in 1998 by the American Academy
of Arts and Sciences. The brain was simply not available for
examination. Hidden in "a relatively impenetrable box, the
skull," the human brain could not be readily probed or excised
during life, but only after death. All knowledge about how the
brain functioned was remote, deduced from human behavior. That
began to change in 1972 with the arrival of computerized tomography
(CT) scans and later positron-emission tomography (PET) scans
which could turn out clear images of brain anatomy and metabolism
and track chemicals as they made their way through elaborate
pathways in the brain. With this remarkable new noninvasive technology,
our interest definitely perked up. For the first time, we humans
can now begin to understand in remarkable detail the structure
and function of the source of our unique place in the universe-how
our brain works and how we can make it work even better. The
ancient mystery is yielding to twenty-first century knowledge.
Fantastic Pictures of
the Living Brain
At one time, the only way scientists
could study the anatomy of the brain was by examining dead brain
tissue. Of course, they still study autopsied brain slices under
electron microscopes. But the study of dead brain cells has given
way to exquisite observations of live brain cells in action.
Much of the revolutionary thinking about the brain is made possible
by new technology that allows scientists to peer inside the brain
as it is thinking, processing information, learning new things,
consolidating memory and expressing anger, depression, even having
hallucinations and psychotic episodes. The remarkable new field
of brain imaging can reveal even the voices of demons lurking
in the brains of schizophrenics. For example, the October 1995
issue of Time magazine showed a "snapshot of a hallucination,"
a freeze-frame of a brain with six red-orange blobs, indicating
hot spots of intense activity captured on a PET scan. The hot
colors occurred every time a twenty-three-year-old paranoid schizophrenic
pressed a button to signal he was having a hallucination of disembodied
heads shouting abuse and commands at him. These brain images
not only confirm brain activity and help diagnose mental problems,
but also offer concrete evidence of beneficial brain changes
induced by various nutrients, drugs, hormones, and herbal treatments.
Sophisticated colorful 3-D
brain images can trace the routes of neurotransmitters as they
congregate to elicit mood changes and lay down long-term memory.
Scientists using brain images can witness the amount of blood
flow to areas of the brain and how much energy the brain useshow
it bums glucose-to perform a task. Generally, the greater the
blood flow and the more glucose consumed, the harder the brain
is working. In some studies...
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