Page 46 - Advanced Biblical Counseling Student Textbook

The Brain’s Plasticity

When damaged, can the brain repair or reorganize itself?

Plasticity is the brain’s ability to change, especially during childhood, by reorganizing after damage or by
building new pathways based on experience. Some of the effects of brain damage can be traced to two
hard facts. (1) Severed neurons, unlike cut skin, usually do not repair themselves. (If your spinal cord
were severed, you probably would be permanently paralyzed.) And (2) some brain functions seem
forever linked to specific areas. One newborn who suffered damage to the facial recognition areas on
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both temporal lobes later remained unable to recognize faces.

But there is good news: Plasticity is the brain’s ability to change, especially during childhood, by
reorganizing after damage or by building new pathways based on experience. The brain’s impressive
plasticity allows it to modify itself after some types of damage. Some brain tissue can reorganize in
response to damage. Under the surface of our awareness, the brain is constantly changing, building new
pathways as it adjusts to little mishaps and new experiences.

Plasticity may also occur after serious damage, especially in young children. If a slow-growing tumor
disrupts language, the right hemisphere may compensate. If a finger is lost, the sensory cortex that
received its input will begin to pick up signals from the neighboring fingers, which then become more
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sensitive.

Although the brain often attempts self-repair by reorganizing existing tissue, it sometimes attempts to
mend itself by producing new neurons. Evidence of this process, known as neurogenesis, has been found
in adult mice and humans. These baby neurons originate
deep in the brain. They may then migrate elsewhere and
form connections with neighboring neurons.
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Left Brain – Right Brain
How many brains do you have – one or two? You only
have one brain, but the cerebral hemispheres are divided
right down the middle into a right hemisphere and a left
hemisphere. Each hemisphere appears to be specialized
for some behaviors. The hemispheres communicate with
each other through a thick band of 200-250 million nerve
fibers called the corpus callosum.
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Handedness
Are you right-handed or left-handed? As you probably
know, 90% of the population are right-handed. They
prefer to use their right hand to write, eat and throw a

71 Ibid.
72 Ibid.
73 Ibid.
74 Ibid.

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