Argument53 [Jet小组]第五次作业（降黑素与害羞）

michael_1984UID: 2327441

Argument53 [Jet小组]第5次作业

TOPIC: ARGUMENT53 - Thirteen years ago, researchers studied a group of 25 infants who showed signs of mild distress when exposed to unfamiliar stimuli such as an unusual odor or a tape recording of an unknown voice. They discovered that these infants were more likely than other infants to have been conceived in early autumn, a time when their mothers' production of melatonin-a hormone known to affect some brain functions-would naturally increase in response to decreased daylight. In a follow-up study conducted earlier this year, more than half of these children-now teenagers-who had shown signs of distress identified themselves as shy. Clearly, increased levels of melatonin before birth cause shyness during infancy and this shyness continues into later life.
WORDS: 450          TIME: 01:26:04          DATE: 2008-2-14 17:06:08

In the argument the author points out a study showing a group of 25 infants who showed sighs of mild distress when exposed to unfamiliar stimuli were more likely to be conceived in early autumn, when their mothers' production of melatonin would increase. And the author also cites a follow-up study showing those infancies involving in the earlier study are more likely becoming shy. On the basis of these evidence, the author conclude that the high levels of melatonin before birth lead to shyness in their life. Close scrutiny of these supporting evidence, however, reveals they lend little credible support to the conclusion.

The threshold problem is about the definition of shyness, which the author fails to define this critical term. Without the clear definition of shyness, we are not informed whether the signs of mild distress when exposed to unfamiliar stimuli illustrated signs of shyness. It is entirely possible that those signs just resulted from uncomfortable physical feeling when those infants were exposed to unfamiliar stimuli. Absent the clear definition of shyness, the author's contention is unjustifiable.

Even if concede the signs shown in the first study could manifest feelings of shyness, the author assumes that there's no other factors leading to the mild distress instead of levels of melatonin before birth, yet the author fails to provide any information to substantiate the crucial assumption. Perhaps levels of melatonin are unnecessary to those signs of mild distress. Moreover, the author even fails to point out whether the affection of melatonin is to the mother or to the baby. Maybe the melatonin affected some brain functions of the mother, but not that of he baby. In each event, the author's contention about the relationship between melatonin and shyness is untenable.

Before I come to my conclusion, it is necessary to point out another flaw appeared in the argument. Even if I concede the melatonin can affect the baby's brain functions, the author commits a hasty generalization from the later study about reasons for teenagers' showing shyness. We are not provided any information about growing circumstances of those teenagers, which may play a critical role in forming one's characteristic including shyness. Moreover, common sense indicates the later experiences also contribute to one's features and may change one's characteristic. Without ruling out other possibilities of forming the characteristic of shyness, I cannot accept the author's conclusion that increased levels of melatonin before birth cause shyness and this shyness will continues into later life with confidence.

To sum up, since the author fails to consider and eliminate other possibilities, his or her conclusion cannot be taken seriously. To better his or her conclusion, the author should provide more information about the affection of the melatonin.