大学英语六级分类模拟题452
(总分445, 做题时间90分钟)
Reading Comprehension
Section A
Why Teenagers Act Crazy
A. Adolescence is practically synonymous in our culture with risk taking, emotional drama and all forms of strange behavior. Until very recently, the widely accepted explanation for adolescent angst has been psychological. Developmentally, teenagers face a number of social and emotional challenges, like starting to parate from their parents, getting accepted into a peer group and figuring out who they really are. It doesn"t take a psychoan
alyst to realize that the are anxiety-provoking transitions.
B. But there is a darker side to adolescence that, until now, was poorly understood: a surge during teenage years in anxiety and fearfulness. Largely becau of a quirk (古怪) of brain development, adolescents, on average, experience more anxiety and fear and have a harder time learning how not to be afraid than either children or adults.
C. Different regions and circuits of the brain mature at very different rates. It turns out that the brain circuit for processing fear—the amygdala (杏仁核)—is precocious (早熟的) and develops way ahead of the prefrontal cortex (前额皮质), the at of reasoning and executive control. This means that adolescents have a brain that is wired with an enhanced capacity for fear and anxiety, but is relatively underdeveloped when it comes to calm reasoning.
不可估量D. You may wonder why, if adolescents have such enhanced capacity for anxiety, they are such novelty ekers and risk takers. It would em that the two traits are at odds. The answer, in part, is that the brain"s reward center, just like its fear circuit, matures earlier than the prefrontal cortex. That reward center drives much of teenagers" risky beh
avior. This behavioral paradox also helps explain why adolescents are particularly prone to injury and trauma. The top three killers of teenagers are accidents, homicide and suicide. The brain-development lag has huge implications for how we think about anxiety and how we treat it. It suggests that anxious adolescents may not be very responsive to psychotherapy that attempts to teach them to be unafraid, like cognitive behavior therapy, which is zealously prescribed for teenagers.
E. What we have learned should also make us think twice—and then some—about the ever rising u of stimulants in young people, becau the drugs may worn anxiety and make it harder for teenagers to do what they are developmentally suppod to do: Learn to be unafraid when it is appropriate to do so. Of cour, most adolescents do not develop anxiety disorders, but acquire the skill to modulate (调节) their fear as their prefrontal cortex matures in young adulthood, at around age 25. But up to 20 percent of adolescents in the United States experience a diagnosable anxiety disorder, like generalized anxiety or panic attacks, probably resulting from a mix of genetic factors and environmental influences. The prevalence of anxiety disorders and risky behavior (both of
which reflect this developmental disjunction in the brain) have been relatively steady, which suggests to me that the biological contribution is very significant.
F. One of my patients, a 32-year-old man, recalled feeling anxious in social gatherings as a teenager. "It was viscerally (出自内心地) unpleasant and I felt as if I couldn"t even speak the same language as other people in the room," he said. It wasn"t that he disliked **pany; rather, socializing in groups felt dangerous, even though intellectually he knew that wasn"t the ca. He developed a strategy to deal with his discomfort: alcohol. When he drank, he felt relaxed and able to engage. Now treated and sober for veral years, he still has a trace of social anxiety and still wishes for a drink in anticipation of socializing.
G. Of cour, we all experience anxiety. Among other things, it"s a normal emotional respon to threatening situations. The hallmark of an anxiety disorder is the persistence of anxiety that caus inten distress and interferes with functioning even in safe ttings, long after any threat has receded. We"ve recently learned that adolescents show heightened fear respons and have difficulty learning how not to be afraid. In one study using brain M. R. I., rearchers at Weill Cornell Medical College and Stanford Univ
ersity found that when adolescents were shown fearful faces, they had exaggerated respons in the **pared with children and adults.
H. The amygdala is a region buried deep beneath the cortex that is critical in evaluating and responding to fear. it nds and receives connections to our prefrontal cortex alerting us to danger even before we have had time to really think about it. Think of that split-cond adrenaline (肾上腺素) surge when you e what appears to be a snake out on a hike in the woods. That instantaneous fear is your amygdala in action. Then you circle back, take another look and this time your prefrontal cortex tells you it was just a harmless stick. Fear learning lies at the heart of anxiety and anxiety disorders. This primitive form of learning allows us to form associations between events and specific cues and environments that may predict danger. Way back on the savanna (热带草原), for example, we would have learned that the rustle in the grass or the sudden flight of birds might signal a predator—and taken the cue and run to safety. Without the ability to identify such danger signals, we would have been lunch long ago. But once previously threatening cues or situations become safe, we have to be able to re-evaluate them and
suppress our learned fear associations.
I. Another patient I saw in consultation recently, a 23-year-old woman, described how she became anxious when she was younger after eing a commercial about asthma (哮喘). "It made me incredibly worried for no reason, and I had a panic attack soon after eing it," she said. As an older teenager, she became worried about getting too clo to homeless people and would hold her breath when near them, knowing that "this was crazy and made no n". B. J. Cay, a professor of psychology and the director of the Sackler Institute at Weill Cornell Medical College, has studied fear learning in a group of children, adolescents and adults. Subjects were shown a colored square at the same time that they were expod to an aversive (令人反感的) noi. The colored square, previously a neutral stimulus, became associated with an unpleasant sound and elicited a fear respon similar to that elicited by the sound.
J. What Dr. Cay and her colleagues found was that there were no differences between the subjects in the acquisition of fear conditioning. But when Dr. Cay trained the subjects to esntially unlearn the association between the colored square and the noi—
2011上海高考作文
a process called fear extinction—something very different happened. With fear extinction, subjects are repeatedly shown the colored square in the abnce of the noi. Now the square, also known as the conditioned stimulus, los its ability to elicit a fear respon. Dr. Cay discovered that adolescents had a much harder time "unlearning" the link between the colored square and the noi than children or adults did.
K. In effect, adolescents had trouble learning that a cue that was previously linked to something aversive was now neutral and "safe". If you consider that adolescence is a time of exploration when young people develop greater autonomy, an enhanced capacity for fear and a more persistent memory for threatening situations are adaptive and would confer survival advantage. In fact, the developmental gap between the amygdala and the prefrontal cortex that is described in humans has been found across mammalian species, suggesting that this is an evolutionary advantage. This new understanding about the neurodevelopmental basis of adolescent anxiety has important implications, too, in how we should treat anxiety disorders. One of the most widely ud and empirically supported treatments for anxiety disorders is cognitive behavior therapy, a form of extinction learnin
例子英语g in which a stimulus that is experienced as frightening is repeatedly prented in a nonthreatening environment. If, for example, you had a fear of spiders, you would be gradually expod to them in a tting where there were no dire conquences and you would slowly lo your arachnophobia (蛛蛛恐惧症). The paradox is that adolescents are at incread risk of anxiety disorders in part becau of their impaired ability to successfully extinguish fear associations, yet they may be the least responsive to densitization (脱敏) treatments like cognitive behavior therapy precily becau of this impairment.
L. But we do know this.. Adolescents are not just carefree novelty ekers and risk takers; they are uniquely vulnerable to anxiety and have a hard time learning to be unafraid of passing dangers. Parents have to realize that adolescent anxiety is to be expected, and to comfort their teenagers—and themlves—by reminding them that they will grow up and out of it soon enough.
1.
混淆怎么读
People suffering from an anxiety disorder tend to have enduring anxious feelings after any threat has faded.
2.
For teenagers, the region for reasoning in the brain develops slower than the brain circuit for processing fear and anxiety.
3.
That the amygdala and the prefrontal cortex in mammals mature at different speeds is an
evolutionary advantage.
4.
Alcohol helps some people to relax when they feel anxious in social activities.
5.
The earlier maturity of the reward center partly accounts for adolescents" risky behavior.
6.
Adolescents have to experience a ries of anxiety-provoking challenges.
7.
栓Parents should remind their kids that adolescent anxiety is normal and can be got over soon.
8.
Rearchers found teenagers were prone to get trouble in unlearning the negative feelings linked to the conditioned stimulus.
9.
Most teenagers are able to control fear as their prefrontal cortex fully develops in their mid-twenties.
10.
wolfen
The amygdala delivers information about danger to the prefrontal cortex as soon as the **
es.
Section B
Passage One
The fridge is considered a necessity. It has been so since the 1960s when packaged food first appeared with the label: "store in the refrigerator."
In my fridgeless fifties childhood, I was fed well and healthily. The milkman came daily, the grocer, the butcher, the baker, and the ice-cream man delivered two or three times a week. The Sunday meat would last until Wednesday and surplus bread and milk became all kinds of cakes. Nothing was wasted, and we were never troubled by rotten food. Thirty years on food deliveries have cead, flesh vegetables are almost unobtainable in the country.
The invention of the fridge **paratively little to the art of food prervation. A vast way of
well-tried techniques already existed—natural cooling, drying, smoking, salting, sugaring,
What refrigeration did promote was marketing—marketing hardware and electricity, marketing soft drinks, marketing dead bodies of animals around the globe in arch of a good price.
Conquently, most of the world"s fridges are to be found, not in the tropics where they might prove uful, but in the wealthy countries with mild temperatures where they are climatically almost unnecessary. Every winter, millions of fridges hum away continuously, and at vast expen, busily maintaining an artificially-cooled space inside an artificially-heated hou—while outside, nature provides the desired temperature free of charge.
The fridge"s effect upon the environment has been evident, while its contribution to human happiness has been insignificant, If you don"t believe me, try it yourlf, invest in a food cabinet and turn off your fridge next winter. You may miss the hamburgers, but at least you"ll get rid of that terrible hum.
1.
The statement "In my fridgeless fifties childhood, I was fed well and healthily." (Line 1, Para. 2) suggests that ______.
A the author was well-fed and healthy even without a fridge in his fifties
B the author was not accustomed to u fridges even in his fifties
C there was no fridge in the author"s home in the 1950s
D the fridge was in its early stage of development in the 1950s西安培训网
2.
prai
英语音标快速记忆法Why does the author say that nothing was wasted before the invention of fridges?
A People would not buy more food than was necessary.
B Food was delivered to people two or three times a week.
C Food was sold fresh and did not get rotten easily.
石家庄雅思考试时间D People had effective ways to prerve their food.
3.
Who benefited the least from fridges according to the author?
A Inventors.
B Consumers.
C Manufacturers.
D Travelling salesmen.
