argument53 酒香

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Argument-53 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.

Based on an experiment and its follow-up study, and the fact that the production of melatonin increase in response to decreased daylight, the writer attributes shyness during infancy and in later life to increased levels of melatonin before birth. The argument seems at first glance to be reasonable, but it contains several facets that are questionable.


Firstly, the author assumes that melatonin in mother’s corpora does have effects on foetus. Truly it is the fact that melatonin affect some brain functions, but there is no further research to probe into whether melatonin affects mothers or foetus, or both. If melatonin does not penetrate the placenta at all, the remaining argument is certainly unwarranted. Even if melatonin enter into baby’s body, Lacking more specific information about how melatonin function in the body, it is impossible to make an informed recommendation. It is suggested that the author offers detailed physiological action of melatonin.


Secondly, there are some problems in the study done before thirteen years ago. On the one hand, 25 is too little to be representative. Maybe it can be persuasive if the objects are hundreds and selected randomly. On the other hand, as said in the argument, 25 infants showed signs of mild distress when exposed to unfamiliar stimuli. What is worth noticing is that mild distress does not really mean shyness. It is probably that an unusual odor caused sort of queasy, or the tape volume went beyond acceptable level and then infants showed mild distress, after all they cannot express themselves through words. Consequently, unless prove those infants were shy when they showed mild distress, the research cannot support the conclusion in the least.



Thirdly, the argument ignores many more factors beyond hormone are involved in shaping one’s character. For example, how parents behave when they are exposed to unfamiliar environment can impress their children indirectly. In other words, if parents are sanguine children may be also sanguine and self-confident, while parents are shy, then children are more likely shy too. And such kind of factors can be, to illustrate more, friends, teachers, and even the whole social atmosphere. However, the follow-up study, which only provides the self-assessments of those teenagers, is too narrow to evaluate the reason they feel shy. Therefore, to be more exact, more inquiries should be included in order to get an exact comprehensive result.

Overall, the argument, while it seems logical at first, has several flaws as discussed above. The argument could be improved by providing evidence that the correlation is indeed a causal relationship—that increased level of melatonin before birth cause shyness during infancy and this shyness continues into later life.