【09GRE作文冲刺组】ccd2月23日作文

ccdUID: 2535452

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: 453
TIME: 00:45:00
DATE: 2009-2-23 20:48:30

In this argument, the speaker infers that the increased levels of melatonin before birth cause shyness during infancy and later life. To support this conclusion, the speaker cites a stduy contained 25 infants and fingers out that those who have showed signs of mild distress when exposed to unfamiliar stimuli are more likely to be born in early autumn, when their mothers’ melatonin increased. And the follow-up study shows that thoes children, now teenagers, identified themselves as shy. This argument is actually groundless as the assumptions it stands are unpersuasive.

First of all, study conducted thirteen years ago is flawed since the sample size is too small and the experimental method is questionable. To begin with, 25 infants is not an enough sample size. Only 25 infants cannot exclude all the exceptations and coincedance. Perhaps only one or two infants in the 25 are responded the experiment with signs of mild distress, and the one or two is "luckly" the infants conceived in early autumn. Then, the experiment to stimulate the infants with an unusual odor or a tape recording of an unknown vice can possibly cause the same result to most infants as an instinct. Thus, the speaker cannot simplely define the signs of mild distress as shyness.

What's more, the evidence is not provided to suggest that the melatonin have the influence upon the infants. Even if the study is objective, the speaker cannot ruling out all the possible factors, except the melatonin, that could make a difference upon the infants. For example, the cool climate of the early autumn which can paceate the mothers, and indirectly influence the little babies. The argument only informs us that the melatonin is a hormone known to affect some brain functions, even overlooks the important fact that which one, the mother or the infants, would be affected.

Finally, the follow-up study is unpersuasive as well. On one hand, the date of the follow-up study is too vague to support the speaker’s conclusion in spite of the small sample size. On the other hand, the augument also relies on the assumption the response themselves are reliable. Yet, the speaker overlooks the possibilities that those teenagers cannot identify themselves objectively. Even so, one’s charactoristic is influenced by many factors, such as the background and the environment. Without being informed with more exact evidence, the speaker could hardly convince me that the increased levels of melatonin before birth would cause shyness and it will
continues into later life.

In conclusion, the speaker should improve the experiment method and provide more scientific data to support the function of the melatonin. What’s more, the speaker should find an objective standard to evaluate the true type of the teenagers’ characteristics.