Learning disabilities are very common. They affect perhaps 10 percent of all children. Four times as many boys as girls have lea

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问题     Learning disabilities are very common. They affect perhaps 10 percent of all children. Four times as many boys as girls have learning disabilities.
    Since about 1970, new research has helped brain scientists understand these problems better. Scientists now know there are many different kinds of learning disabilities and that they are caused by many different things. There is no longer any question that all learning disabilities result from differences in the way the brain is organized.
    You cannot look at a child and tell if he or she has a learning disability. There is no outward sign of the disorder. So some researchers began looking at the brain itself to learn what might be wrong.
    In one study, researchers examined the brain of a learning-disabled person, who had died in an accident. They found two unusual things. One involved cells in the left side of the brain, which control language. These cells normally are white. In the learning-disabled person, however, these cells were gray. The researchers also found that many of the nerve cells were not in a line the way they should have been. The nerve cells were mixed together.
    The study was carried out under the guidance of Norman Geschwind, an early expert on learning disabilities. Doctor Geschwind proposed that learning disabilities resulted mainly from problems in the left side of the brain. He believed this side of the brain failed to develop normally. Probably, he said, nerve cells there did not connect as they should. So the brain was like an electrical device in which the wires were crossed.
    Other researchers did not examine brain tissue. Instead, they measured the brain’s electrical activity and made a map of the electrical signals.
    Frank Duffy experimented with this technique at Children’s Hospital Medical Center in Boston. Doctor Duffy found large differences in the brain activity of normal children and those with reading problems. The differences appeared throughout the brain. Doctor Duffy said his research is evidence that reading disabilities involve damage to a wide area of the brain, not just the left side.
Which of the following is NOT mentioned in the passage?

选项 A、Learning disabilities may result from the unknown area of the brain.
B、Learning disabilities may result from damage to a wide area of the brain.
C、Learning disabilities may result from abnormal organization of brain cells.
D、Learning disabilities may result from problems in the left side of the brain.

答案A

解析 本题问下面哪个选项文章中没有提到。针对四个选项,利用查阅式阅读法,结合原文相关内容,我们可以发现:B“学习上的缺陷可能是对整个大脑的损伤造成的”。最后一段指出,杜菲医生测试大脑电波活动,制成脑波图,利用这种方法,他发现,正常儿童和有阅读问题的儿童大脑的活动存在着很大不同,不同点存在于整个大脑,由此他得出结论,阅读的缺陷不只是由大脑的左半球造成的,而是由对整个大脑的损伤造成的。C“学习上的缺陷可能是由脑细胞的不正常排列造成的”。第四段指出,在一种试验中,研究者检验在事故中丧生的学习上有缺陷的人的大脑,他们有两个异常发现:(1)大脑的左半球控制着语言能力,左半球的脑细胞应该是白色的,但是,有学习缺陷的人的左半球的脑细胞却是灰色的;(2)在有学习缺陷的人的大脑中,许多脑细胞不是像正常细胞一样呈线状排列的,而是团在一起的。第五段第四、五句也指出,在戈士温德医生看来,有学习缺陷的人的大脑细胞也许连接不正常,因为,大脑细胞的连接方式就像电器设备里的线路,不能连错。D“学习上的缺陷可能是大脑左半球的问题造成的”。第五段第二、三句指出,根据戈士温德医生的试验,他提出,学习上的缺陷主要是大脑左半球的问题造成的,他认为,这些人的大脑左半球发育不正常。因此,选择项B、C、D表达的内容都与原文相符。所以,本题的正确答案应是A“学习上的缺陷可能是大脑的某个未知区域造成的”。
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