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Brain Plasticity
By:
Rebecca Daly

It was a mere twenty years ago that people thought the brain developed during childhood and thereafter there was little room for alterations in the brain. Today, psychologist know that the brain has an enormous capacity for changes. The term that describes the ability of the nervous system to adapt to changed circumstances and to find new ways of learning is plasticity. An excellent example of brain plasticity is a five-year old having to have his entire left hemisphere removed so as to prevent severe seizures. Although half of his skull is filled with cerebrospinal fluid, the child has completed college and is attending graduate school. This is all possible because of the brain’s incredible ability to reorganize itself, even after such a trauma as this one. Previously, most psychologists had willingly gone along with the idea that the brain’s highest point of plasticity is during childhood, before cortical regions’ functions become set. However, some psychologists are questioning this idea through studies with violinists and even Braille readers. Professor Thomas Elbert is one of these psychologists calling forth the issue of malleability and plasticity in the brain. Elbert’s main point is that the adult brain is nearly as malleable and plastic as the child’s.

The reason he chose to look at violin players, Elbert says, is because they use their left hand to finger the strings, which is a prime example of the representation of the left-hand fingers and the right hemisphere of the brain. It is known that the left hemisphere, which is the dominant hemisphere, dictates the movements for the right side of the body and the right hemisphere for the left side of the body. In fact, the hand representation in the brain gets enlarged and so, the brain assigns more tissue and more neural components to the processing of the fingers. All of these findings are compared to non-string players, confirms Elbert. Many other studies that he is conducting have found that if adult people start playing the violin, they too will change their representation, but not to the extent of when someone starts playing at a younger age. This may be a very shocking discovery for some considering that it was once believed the brain only changed throughout childhood and stopped after that.

All of this is not studied through cutting someone’s skull open. That is simply not accepted today. There was once a famous Canadian neurosurgeon who measured with electrodes physically while he happened to be operating on a patient’s brain. This man would get the patient’s to move their hands so that he could measure. Because neural elements function electronically, an example of this is in how neurotransmitters communicate, Elbert tells that every electric current has a magnetic field , which is shaped by the electric current and psychologists are able to detect this magnetic radiation inside the brain. Elbert not only studied violinists, but he also studied Braille readers in his studies of brain plasticity.

Elbert’s work with Braille readers have also been of great importance and value in this study of brain reorganization. Elbert investigated Braille readers that used only one finger to read and others that used various fingers at a time to read. Much like the violin players, these people that use several fingers to read many hours a day have developed a “kind of merged, giant large finger, or a large representation of all the fingers simultaneously in the brain.” Elbert feels that it is quite amazing how these people perceive in their brain all that information from all those different fingertips at the same time. One down side is, though, that the Braille readers cannot determine where the information comes from. One type of comparison of this disordered representation, Elbert says, is how normal people do not see nor move the toes as individuals. When people wiggle their toes in their shoes, they simultaneously wiggle all of the toes, not each one separately, but we do develop separate representations of our fingers in the brain. These blind Braille readers, who use three fingers to read, would not be sure which finger was being touched if one of the three were touched. Normal people can distinguish between fingers if they were touched. This example is similar to that of touching someone’s toes; they would not be able to tell which toe was being touched. Those who use three fingers to read are not able to do this because the information fuses together inside the brain and then they can no longer tell where the information comes from. As for one-finger Braille readers, their one finger that is used becomes an enlarged representation and, in a way, a super finger. The amount of adaptation for those adults that start to read Braille at an older age compared to children who started much earlier is smaller and has a plasticity of about half as large as that of an adult’s. In conclusion, these findings may help when applied to various disorders and for some musicians that have their fingers seen as one in the brain, which will cause hand-cramping. To fix this problem, though, Elbert says that a training schedule and ways to move the fingers to separate these brain regions again will help these people.

Much of this information expanded my knowledge on brain plasticity, being that we only briefly discussed this in class. In Chapters two and three we studied about how the brain is capable of taking over the operations and functions of one part if something were to happen to that particular region. A child even had half of her brain removed to stop unbearable seizures from occurring, but still leads an almost normal life, with the exception of a paralyzed side of her body. I really chose this article because non of the others caught my attention when I read over them, but did remember watching a movie in class about the little girl and the amazing ability of plasticity. After reading this article, it is very shocking to me how our bodies and minds take over and reorganize themselves. I liked this article because it did not have that many scientific terminology, but did explain everything very clearly. It gave alot of examples to clarify any confusing points that were covered. I would recommend this article to someone if they enjoy learning about the brain and its capabilities. It is not a hard reading and I think is very interesting. Some of the examples, such as the toes example, really explained some points I did not understand. This is just a good article and really expands on brain plasticity.

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This article is copyrighted Rebecca Daly, 1999, and must not be removed from this page without the written consent of the original author.