Neuroscientists have explained the risky, aggressive or just plain confusing behavior of teenagers as the product of a brain that is somehow compromid. Groundbreaking rearch in the past 10 years, however, shows that this view is wrong. The teen brain is not defective（有缺陷的）. It is not a half-baked adult brain, either. It has been forged by evolution lo function differently from that of a child or an adult.
Foremost among the teen brain’s features is its ability to change in respon to the environment by modifying the communication networks that connect brain regions. It allows teenagers to make enormous in thinking and socialization. But the change also makes them nsitive to dangerous behavior and rious mental disorders.
The most recent studies indicate that the riskiest behavior aris from a mismatch between the maturation of networks in the limbic system（边缘系统）, which drives emotions and intensifies at (青春期）, and the maturation of networks in the prefrontal cortex （前额皮质） , which occurs later and promotes sound judgment and the control of impuls. Indeed, we now know that one’s prefrontal cortex continues to change prominently until his 20s. And yet puberty ems to starling earlier, extending the “mismatch years”.
The plasticity of networks linking brain regions—and not the growth of tho regions, as previously thought—is key to eventually behaving like an adult. Understanding that, and knowing that a widening gap between the development of emotional and judgment networks is happening in young people today, can help parents, teachers, counlors and teenagers themlves. People will better e that behavior such as risk-taking, nsation-eking, and turning away from parents and toward peers are not signs of cognitive or emotional problems. They are a natural result of brain development, a normal part of adolescents learning how to negotiate a complex world.
The same understanding can also help adults decide when to intervene. A 15-year-old girl’s departure from her parents' tastes in clothing, music or politics may be a source of anxiety for Mom and Dad hut does not indicate mental illness. A 16-year-old boy’s tendency to skateboard without a helmet or to accept risky challenges from friends is not unimportant but is more likely a sign of short-range thinking and peer pressure than a desire to hurt himlf. Other exploratory and aggressive actions might be red flags, however. Knowing more about the unique teen brain will help all of us learn how to par
ate, unusual behavior that is age-appropriate from that which might indicate illness. Such awareness could help society reduce the rates of teen addiction, motor vehicle accidents and depression.
题一
61. How is Paragraph 1 mainly developed?
A. By drawing a comparison.
B. By confirming a prediction.
C. By making an assumption.
D. By correcting a misunderstanding.
62. What can we know about the changeability of teens’ brains?
A. It is predictable and avoidable.
B. It is a double-edged sword.
C. It is related to their brain development in the childhood.
D. It results from rious functional disorders.
63. The limbic system and the prefrontal cortex are mentioned in Paragraph 3 to .
A. show how the mismatch between their maturation of networks happens
B. explain the relationship between early puberty and them
C. explain what leads to teens’ riskiest behavior
D. show the differences between them
64. What are the last two paragraphs mainly about?
A. The important role of adults in teenagers, development.
B. Long-term prospects for the rearch of teenagers’ brains.
C. Possible cognitive and emotional problems of teenagers.
D. The significance of the new discovery.
C篇
61.D。写作手法题。文章第一段第一句给出了神经学家对青少年的青春期叛逆行为已有的解释.该段接下来 的部分是对该解释进行否定，指出青春期大脑是进化过程的产物，与儿童和成年人大脑的活动方式均不相同。 故选D项。
62. B。推理判断题。根报第二段的It allows rious mental disorders可知，青少年大脑的可变性是一把双刃剑，它既可以使青少年的思考和社交能力突飞猛进.也容易导致危险行为的发生，并使他们患上严重的精神疾病。
63.C。细节理解题。第三段指出大脸边缘系统与前额皮质脑组织的成熟期不一致，导致青少年青春期危险行 为的发生。因此，文章第三段提到大脑边缘系统与前额皮质是为了解释说明导致靑少年危险行为发生的原因。64.D。段落大意题。文章最后两段指出了这项新发现的现实意义。第一，认识到青少年大脑的可塑性与不同脑区的成熟时间差异有助于父母
、老师和青少年正确认识青春期的种种行为。第二，上述认识还可以帮助成年人决定何时作出干预。
题二
61. The word “defective” in the first paragraph possibly means not_____.
A. perfect B. enormous C. mature D. advanced
62. The cond paragraph is mainly about______.
A. features of teen brain’s B. changes of teen brain’s
C. effects brain change can bring D. parate aspects of brain changes
63. The limbic system and the prefrontal cortex are mentioned in Paragraph 3 to_____.
A. show how the mismatch between their maturation of networks happens
B. explain the relationship between early puberty and them
C. explain what leads to teen’s riskiest behavior
D. show the differences between them
64. What’s the main purpo of the whole passage?
A. To introduce a new rearch about teens’ brain
B. To provide some information about teens’ brain
C. To understand the development of teens’ brain
D. To describe inside structure of teens’ brain and how it functions.
ADCC
以下选段出自《科学美国人》中一篇名为“神奇的青少年大脑”的文章。文章指出青少年大脑与儿童、成人的大脑均不同，具有可塑性这一特质，且大脑不同脑区的成熟速度不一致，导致青少年一方面易冲动、爱冒险，另一方面又有快速适应环境的能力。对青少年大
脑的深入了解将有助于父母和社会学会分辨青春期典型行为与精神疾病，从而帮助青少年健康成长。本文属科普类文章，探讨的对象为青少年大脑这一研究热点，从青春期行为入手，话题有吸引力，值得一读。
【原文】
I①Neuroscientists have explained the risky, aggressive or just plain baffling behavior of teenagers as the product of a brain that is somehow compromid. ②Groundbreaking rearch in the past 10 years, however, shows that this view is wrong. ③The teen brain is not defective. ④It is not a half-baked adult brain, either. ⑤It has been forged by evolution to function differently from that of a child or an adult.
