求助OG 114题！！！

elaine0

114. Normally, the pineal gland governs a person’s sleep-wake cycle by secreting melatonin in response to the daily cycle of light and darkness as detected by the eye. Nonetheless, many people who are totally blind due to lesions in the visual cortex of the brain easily maintain a 24-hour sleep-wake cycle. So the neural pathway by which the pineal gland receives information from the eye probably does not pass through the visual cortex.
For purposes of evaluating the argument it would be most useful to establish which of the following?

(A) Whether melatonin supplements help people who have difficulty maintaining a 24-hour sleep cycle to establish such a pattern
(B) Whether the melatonin levels of most totally blind people who successfully maintain a 24-hour sleep-wake cycle change in response to changes in exposure to light and darkness
(C) Whether melatonin is the only substance secreted by the pineal gland
(D) Whether most people who do not have a 24-hour sleep-wake cycle nevertheless have a cycle of consistent duration
(E) Whether there are any people with normal vision whose melatonin levels respond abnormally to periods of light and darkness

这题到底为什么选B啊 OG的解释完全没看懂啊 求nn解释一下T T
What additional information would be most helpful in evaluating the argument? The argument's conclusion is that the neural pathway by which the pineal gland receives information probably does not pass through the visual cortex.This is suggested by the fact that people without a well-functioning visualcortex (e.g., people with a certain type of blindness) can nonetheless maintain a 24-hour sleep-wake cycle. Is it by the pineal gland's secretion of melaton in that they do so? The argument tells us that normally (i.e.,insightedpeople), this is the mechanism for sleep regulation. But the argument depends on assuming that a similar mechanism is operating in people who are blind but have well-regulated sleep cycles. The best choice will be the one that helps us decide whether that assumption is correct.
A This question would not give us an answer that would help in evaluating the argument. A"no" answer would not clarify whether the pineal gland-melaton in mechanism operates in people who
are blind. A "yes" answer would do no better.The question refers only to people who have sleep dysfunctions (which the argument does not address).
B Correct. Answering this question would provide the most useful information for evaluating the argument. A "yes" answer would help confirm a key assumption of the argument: that blind people rely on the pineal gland-melaton in mechanism for sleep regulation. A"no"answer would help disconfirm that assumption.
C Whether or not there are other substances secreted by the pineal gland makes no difference to the
reasoning. The argument relies on the premise that the pineal gland governs the sleep cycle by secreting melatonin. For example, if the pineal gland sometimes secreted adrenaline, that would still have no bearing on the argument.
D The consistency or inconsistency of the duration of some people's sleep  patterns has no relevance to the reasoning. Their sleep patterns could be due to any of a number of factors.
E This does not help,for there could be sighted people whose melaton in levels respond abnormally simply because of a pineal-gland abnormality.
The correct answer is B.
B选项说：A "yes" answer would help confirm a key assumption of the argument: that blind people rely on the pineal gland-melaton in mechanism for sleep regulation. A"no"answer would help disconfirm that assumption.可是blind people rely on the pineal gland-melaton in mechanism for sleep regulation和题中So the neural pathway by which the pineal gland receives information from the eye probably does not pass through the visual cortex.的结论又有什么关系呢？

huasususu

题目：前提1：一般来说：eye感受光→PG接收信息→分泌M→醒睡周期
          前提2：但是，很多VC损伤的盲人依旧能正常维持醒睡周期
          结论：所以，PG接收来自眼睛的信息的神经通道可能并不是穿过VC的
分析：题目有个隐含前提------就是盲人也是通过eye→PG→M→醒睡周期 这个方式来控制醒睡周期的
          那么我们首先假设这个前提是正确的，那么题目就是：
          前提1：一般来说：eye感受光→PG接收信息→分泌M→醒睡周期
          隐含前提：盲人也是通过eye→PG→M→醒睡周期 这个方式来控制醒睡周期的
          前提2：但是，很多VC损伤的盲人依旧能正常维持醒睡周期
          结论：所以，PG接收来自眼睛的信息的神经通道可能并不是穿过VC的
          我们会发现，这样的argument天衣无缝
          接下来我们假设这个隐含前提错误，也就是说盲人并不是通过eye→PG→M→醒睡周期 这样一个途径来控制醒睡周期 而是通过另一个mechanism来控制醒睡周期
          这样一来VC受伤的盲人能维持醒睡周期这样的事实就完全不能为结论提供有力的依据，因为盲人是通过完全不一样的机制来控制醒睡周期的，已经和PG无关了。
          最后我们来看，我们要评价这个argument，就必须先解决这个隐含前提到底是正确还是错误的！
          而B选项----能维持正常醒睡功能的盲人的M是否随着光的变化而变化→回答是：说明隐含前提正确，argument天衣无缝
                                                                                                                  →回答不是：说明隐含前提错误，argument有缺陷

果然写一遍更能理顺自己的思路！！！

爱吃醋的牙牙

huasususu 发表于 2014-8-31 22:04
题目：前提1：一般来说：eye感受光→PG接收信息→分泌M→醒睡周期
          前提2：但是，很多VC损伤的盲 ...

同意！               

茄子要加油

huasususu 发表于 2014-8-31 22:04
题目：前提1：一般来说：eye感受光→PG接收信息→分泌M→醒睡周期
          前提2：但是，很多VC损伤的盲 ...

Mark一下！               

Ccqy

huasususu 发表于 2014-8-31 22:04
题目：前提1：一般来说：eye感受光→PG接收信息→分泌M→醒睡周期
          前提2：但是，很多VC损伤的盲 ...

看一下！               

暗中观察biubiu

看一下！