In the Argument section, Shenk tries to make the point of
development dynamics by referring to the work of Darold Treffert, psychiatrist
at the University of Wisconsin. Treffert is a leading expert in what is known
as “savant syndrome”. Savant syndrome is illustrated with men like Daniel
Tammet, who lives with autism but can recite 22,514 digits of pi, and Kim Peek,
a man who is extremely disabled physically with a low IQ score but can memorize
thousands of books. Treffert says that these examples are caused by a damaged
left hemisphere which allows the opportunity for the right hemisphere to
develop further. Allan W. Synder provided evidence in his 2003 experiment for
Treffert’s and Shenk’s claim that savant syndrome can potentially develop in anyone.
Although
these savants have incredible abilities, they also have severe impairments as
well. But since Treferret suggests that 1 in 10 patients with autism have
savant abilities to some degree, whatever genes that are part of the autism
dynamic still exists in the gene pool. Could savant abilities be or have been an evolutionary advantage
despite the physical damage it brings? If so, what environmental factors could have promoted them? If not, why are they still prevalent today? Could nature select the “right
brained” people over the left? Explain your answer. (85-90)
Alvin Varghese (alvin.varghese@hotmail.com)
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ReplyDeleteSavant syndrome is defined by Darold Treffert as a rare, but extraordinary, condition in which persons with serious mental disabilities, including autistic disorder, have some 'island of genius' that stands in marked, incongruous contrast to overall handicap” (http://www.wisconsinmedicalsociety.org/savant_syndrome/overview_of_savant_syndrome). While savant syndrome brings about incredible abilities, the severe impairments experienced by savants would make it an evolutionary disadvantage, not an evolutionary advantage. Campbell defines evolution as “a change in the genetic composition of a population from generation to generation” (452). Mutations and genetic recombination generate heritable variation that is subjected to natural selection. In order for the population to obtain these abilities of the savants through natural selection, the savants must enter the gene pool. However, their social impairments make their entrance improbable.
ReplyDeleteMore importantly, savant syndrome is not related to genetics and thus could not be passed on. Savant syndrome is caused by damage to the left-brain hemisphere that causes the right brain to compensate for the loss. The reason for savant abilities being still prevalent is due to the plasticity of the brain and “the brain’s ability to recruit the other areas to be put to use” (89). Savant ability shows the evolutionary marvel of the brain in that even after severe damage it is still able to function.
Nature does not select “right brained people” over “left brained people”. The right brain vs. left brain theory has been distorted and exaggeraged. Research shows that the brain is not as dichotomous as once thought. For example, research shows that ability is math is strongest when both halves of the brain work together (http://psychology.about.com/od/ cognitivepsychology/a/left-brain-right-brain.htm). Natural selection would not select right brained people over left because one side of the brain is not superior over the other one.
Jessica Hua (jhua33@yahoo.com)