10 Rew i r e
Yo u r
B r a i n
The neurons that were required to fi re
with their partners had
teamed up and wired together.
As you become more talented at a specifi c skill, a greater amount
of space in your brain is devoted to making that possible. Alvaro
Pascual - Leone of Harvard Medical School used transcranial mag-
netic stimulation (TMS) to measure specifi c areas of the cortex. He
studied blind people who read braille and found that the cortical
maps for their reading fi ngers were larger than the cortical maps
for their other fi ngers and also for the fi ngers of sighted readers. In
other words, the sensitivity of their reading
fi ngers required more
space. Thus, cultivated movement enhances neuroplasticity, which
creates extra space in the brain.
In another example of the power of neuroplasticity, musicians
who play string instruments were examined to see if their brains had
reorganized to accommodate more space.
There was no difference
between the string - instrument players and the nonmusicians in
how much space was made available in the sensory motor strip (the
area in the center of the brain that controls movement and physical
sensation) for the fi ngers of the right hand (in right - handed players).
However, the area of the brain devoted to the fi ngers of the left hand
(in right - handed players) showed a dramatic difference. The fi ngers
of the left hand must be nimble and dexterous in order to make all
the fretting movements. The cortical space
devoted to the fi ngers
involved in fretting was signifi cantly greater in these musicians than
in nonmusicians. This difference was greatest if the musician had
started playing the instrument before the age of twelve. In other
words, although this use - dependent neuroplasticity occurs during
adulthood, it is more dramatic the earlier and the longer that the
person plays the instrument.
Not only does behavior change the structure
of the brain through
neuroplasticity; just thinking about or imagining particular behaviors
can change brain structure as well. For example, researchers have
shown that simply imagining a session of piano practice contributes
to neuroplasticity in the area of the brain associated with the fi nger
movements of playing the piano. Thus,
mental practice alone con-
tributes to the rewiring of the brain.
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F i r i n g t h e R i g h t C e l l s To g e t h e r
11
How Neuroplasticity Occurs
A process called
long - term potentiation
(LTP) occurs when the exci-
tation between cells is prolonged. This
strengthens the connections
between the cells and makes them more apt to fi re together in the
future. Thus, LTP is relatively long - lasting.
LTP essentially strengthens the affi nity between neurons by
reconfi guring their electrochemical relationship. On the sending
side of the synapse, the stores of glutamate (the excitatory neu-
rotransmitter)
are enhanced, and the receptor side is reconfi gured
to receive more. The voltage on the receptor side becomes stronger
in its resting state, which attracts more glutamate. If the fi ring
between these neurons continues, the
genes within the neurons
are turned on in order to construct more building blocks for the
infrastructure and enhance the relationship.
One of the most important players in both neuroplasticity and
neurogenesis is something called
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