Here is
one definition of “neuroplasticity”: The brain’s ability “to reorganize itself
by forming new neural connections throughout life.” Neurons, also called nerve
cells, can compensate to some extent for head injuries as well as neurological damage
caused by diseases such as Parkinson’s and Alzheimer’s. At one time, scientists
thought that neurons (nerve cells) were finite. But now we know there are ways
to continually give birth to neurons throughout one’s life.
Earlier this week I paid $8 to obtain an article in the
venerable British science journal Nature, titled “Probing plasticity.” But
I would be lying if I claimed to fully understand this text. It was written in
a scientific dialect that would have taken days, maybe weeks, for me to learn. At
the other end of the spectrum, I consulted the website Neuroscience for Kids,
which noted that the human brain has roughly 100 billion neurons at any one
time. An interesting fact, but one that failed to illuminate neuroplasticity.
Elsewhere, I learned that DARPA—the U.S. Defense Advanced
Research Projects Agency—plans to collaborate with seven public research universities
to develop better ways to explore how “stimulation of the human body’s
peripheral nerves can help facilitate cognitive learning.” In the fifteen-plus
years since 9/11, many soldiers have been diagnosed with traumatic brain
injuries.
Most relevant on this topic is an article by Carolyn A.
Scott, who works on behalf of Rainbow Rehabilitation Centers. “An individual
who experiences a traumatic brain injury may also experience deficits in
cognition,” Scott wrote in a lengthy article. “To better understand how the
brain works and recovers from an injury, we must have an understanding of how
the brain learns and adapts to experience. This understanding may also help us determine
which treatments are most effective.”
Two studies completed
in the early years of this century have proven illuminating. In the first
study, published in 2000, established that taxi drivers in London needed three
to four years to master all the routes within the metropolis. In a second study
(2003), the researchers concluded that the immense time the drivers spent on
the road over the years increased their brains’ gray matter, making them, for want
of a more precise term, more intelligent. Particularly impressive were the
gains in short-term memory, which resides in the bilateral hippocampus—the part
of the brain that, in cases of Alzheimer’s, typically experiences the first effects
of the disease.
For the legions of veterans who have sustained serious
brain injuries in combat in Iraq or Afghanistan
over the past fifteen years, neuroplasticity is a crucial concept. According to
the medical definition of plasticity, the brain has the ability “to reorganize
by forming new neural connections throughout life.” Neuroplasticity allows
nerve cells in the brain and adjust their activities to new situations or to
changes in the environment.” In other words, some brain damage that once would
have regarded as permanent now can be treated.
No comments:
Post a Comment