1、大学英语六级综合-阅读(四)及答案解析(总分：50.00，做题时间：90 分钟)一、Passage Six(总题数：1，分数：10.00)The Science of Memory: An Infinite Loop in the BrainJill Price can rattle off, without hesitation, what she saw and heard on almost any given date. She remembers many early childhood experiences and most of the days between the age
2、s of 9 and 15. There are virtually no gaps in her memory.She can also date events that were reported in the media, provided she heard about them at the time. When and where did the Concorde crash? When was O.J. Simpson arrested? When did the second Gulf War begin? Price doesnt even have to stop and
3、think. She can effortlessly recite the dates, numbers and entire stories.“People say to me: Oh, how fascinating, it must be a treat to have a perfect memory,“ she says. Her lips twist into a thin smile. “But its also agonizing.“In addition to good memories, every angry word, every mistake, every dis
4、appointment, every shock and every moment of pain goes unforgotten. Time heals no wounds for Price. “I dont look back at the past with any distance. Its more like experiencing everything over and over again, and those memories trigger exactly the same emotions in me. Its like an endless, chaotic fil
5、m that can completely overpower me. And theres no stop button.“Can someone who cannot forget even fall in love? Can they forgive, either others or themselves? Prices life has had its share of suffering, including family strife, her mothers cancer and, later, the sudden death of her husband Jim. Beca
6、use she was hounded by bad memories, grew depressed and feared that she was going crazy, she sat in front of her computer on June 5, 2000 and typed a single word into Google: memory.That was how Price found James McGaugh, and became part of a scientific case study.McGaugh is one of the leading exper
7、ts on memory in the United States. He founded the Center for the Neurobiology of Learning and Memory at the University of California in Irvine.“I was skeptical, of course, when Jill told me her story,“ says McGaugh, a slim, grey-haired man with glasses. “But Ive spent most of my life studying the me
8、chanisms in the brain that are associated with the development of lasting memories. So I thought that I should at least meet the woman.“McGaugh and his staff realized they were looking at an exotic case, perhaps even a scientific sensation. For that reason they took a thorough approach, and for five
9、 years they subjected Price to batteries of neuropsychological (神经心理学 ) tests, combed the professional literature for similar cases and developed special questionnaires to allow them to test her memory.Once she was asked to write down the dates of all Easter holidays from 1980 to 2003. “It took her
10、10 minutes, and she only got one of the 24 dates wrong, where she was off by two days,“ says McGaugh. He had Price repeat the test two years later, and the second time she got all the dates right. “I thought that was especially impressive,“ says McGaugh, “because she is Jewish. Easter means nothing
11、to her.“McGaugh and his colleagues concluded that Prices episodic memory, her recollection of personal experiences and the emotions associated with them, is virtually perfect. A case like this has never been described in the history of memory research, according to McGaugh. He explains that Price di
12、ffers substantially from other people with special powers of recall, such as autistic savants(自闭学者), because she uses no strategies to help her remember and even does a surprisingly poor job on some memory tests.Its difficult for her to memorize poems or series of numbers-which helps explain why she
13、 never stood out in school. Her semantic memory, the ability to remember facts not directly related to everyday life, is only average.Two years ago, the scientists published their first conclusions in a professional journal without revealing the identity of their subject. Since then, more than 200 p
14、eople have contacted McGaugh, all claiming to have an equally perfect episodic memory. Most of them were exposed as fakes. Three did appear to have similarly astonishing abilities. “Their personalities are very different. The others are not as anxious as Jill. But they achieve comparable results in
15、the tests,“ McGaugh reports. The subjects do have certain compulsive traits in common, says McGaugh, especially compulsive hoarding.In neurobiological terms, a memory is a stored pattern of links between nerve cells in the brain. It is created when synapses in a network of neurons are activated for
16、a short time. The more often the memory is recalled afterwards, the more likely it is that permanent links develop between the nerve cells-and the pattern will be stored as a long-term memory. In theory there are so many possible links that an almost unlimited number of memories can be permanently s
17、tored.So why dont all people have the same powers of recollection as Jill Price? “If we could remember everything equally well, the brain would be hopelessly overburdened and would operate more slowly,“ says McGaugh. He says forgetting is a necessary condition of having a viable memory-except in the
18、 case of Price and the other three memory superstars.For McGaugh, there is another reason why people with such phenomenal memory are so puzzling. They challenge a theory on which his research has been based for the last half a century. This theory, based on clinical observation, says memories are st
19、ored in greater detail and with more staying power when they are tied to emotion.Sensations are emotionally processed in the amygdala, a specific part of the brains limbic system. There decisions are made as to which information should remain in long-term memory. The more powerfully the amygdala is
20、activated, the greater the likelihood of a permanent memory. “But now here we have these four people who seem to violate this principle, because they also remember the most banal and inconsequential things,“ says McGaugh.（分数：10.00）(1).When people admire Prices perfect memory, she shows a thin smile
21、because _.（分数：1.00）A.it just brings her good memoryB.it also causes her some troublesC.she appreciates those praisesD.she is gifted by God(2).Price became depressed and was afraid that she was going crazy because _.（分数：1.00）A.her husband Jim died suddenlyB.she feared about the futureC.she didnt know
22、 why her memory was so perfectD.she was wrenched by bad memories consistently(3).When McGaugh first heard Prices story, _。（分数：1.00）A.he felt she was an odd womanB.he determined to cure heC.he thought it unimaginableD.he didnt plan to meet her(4).When first was asked to write down the dates of all Ea
23、ster holidays from 1980 to 2003, how many mistakes did Price make?（分数：1.00）A.One.B.Two.C.Twenty-two.D.Twenty-four.(5).Price didnt study very well because _.（分数：1.00）A.she preferred to learn poems onlyB.she had difficulties memorizing series of numbersC.she only remembered facts that directly related
24、 to daily lifeD.she didnt pay much attention to her study(6).The other three subjects with perfect episodic memory _.（分数：1.00）A.had different abilitiesB.has different personalitiesC.were as anxious as PriceD.achieved different results in the tests(7).In neurobiological terms, memories can be permane
25、ntly stored when _.（分数：1.00）A.they are stored as pattern of links between nerve cellsB.synapses in a network of neurons are activated for a short timeC.they are stored in more nerve cells in the brainD.permanent links develop between the nerve cells(8).For common people, _ is a necessary condition o
26、f having a viable memory.（分数：1.00）填空项 1:_(9).McGaughs research was based on the theory that memories are stored in greater detail when _.（分数：1.00）填空项 1:_(10).Price and the other three subjects violated McGaughs theory in that they also remember _ things.（分数：1.00）填空项 1:_二、Passage Seven(总题数：1，分数：10.00
27、)The Development of Television TechnologyRadio and television were major agents of social change in the 20th century. Radio was once the center for family entertainment and news. Television enhanced this revolution by adding sight to sound. Both opened the windows to other lives, to remote areas of
28、the world, and to history in the making. News coverage changed from early and late editions of newspapers to broadcast coverage from the scene. Play-by-play sports broadcasts and live concerts enhanced entertainment coverage. For many, the only cultural performances or sports events they would ever
29、hear or see would emanate from the speakers or the screens in their living rooms. Each has engaged millions of people in the major historical events that have shaped the world.If people could look at the sky and see how it is organized into frequency bands used for different purposes, they would be
30、amazed. Radio waves crisscross the atmosphere at the speed of light, relaying incredible amounts of information-navigational data, radio signals, television pictures-using devices for transmission and reception designed, built, and refined by a century of engineers.Key figures in the late 1800s incl
31、uded Nikola Tesla, who developed the Tesla coil, and James Clerk Maxwell and Heinrich Hertz, who proved mathematically the possibility of transmitting electromagnetic signals between widely separated points. It was Guglielmo Marconi who was most responsible for taking the theories of radio waves out
32、 of the laboratory and applying them to practical devices. His “wireless“ telegraph demonstrated its great potential for worldwide communication in 1901 by sending a signal-the letter “s“-in Morse code a distance of 2,000 miles across the Atlantic Ocean. Radio technology was just around the comer.Im
33、mediate engineering challenges addressed the means of transmitting and receiving coded messages, and developing a device that could convert a high frequency oscillating signal into an electric current capable of registering as sound. The first significant development was “the Edison effect“, the dis
34、covery that the carbon filament in the electric light bulb could radiate a stream of electrons to a nearby test electrode if it had a positive charge. In 1904, Sir John Ambrose Fleming of Britain took this one step further by developing the diode which allowed electric current to be detected by a te
35、lephone receiver. Two years later, American Lee De Forest developed the triode, introducing a third electrode (the grid) between the filament and the plate. It could amplify a signal to make live voice broadcasting possible, and was quickly added to Marconis wireless telegraph to produce the radio.R
36、adio development was hampered by restrictions placed on airwaves during World War I. Technical limitations were also a problem. Few people had receivers, and those that did had to wear headsets. Radio was seen by many as a hobby for telegraphy buffs. It would take a great deal of engineering before
37、the radio would become the unifying symbol of family entertainment and the medium for news that was its destiny.In the mid-1920s, technical developments expanded transmission distances, radio stations were built across the country, and the performance and appearance of the radio were improved. With
38、tuning circuits, capacitors, microphones, oscillators, and loudspeakers, the industry blossomed in just a decade. By the mid-1930s almost every American household had a radio. The advent of the transistor in the 1950s completely transformed its size, style, and portability.Both television and radar
39、were logical spin-offs of the radio. Almost 50 years before television became a reality, its fundamental principles had been independently developed in Europe, Russia, and the United States. John Baird in England and Charles Jenkins in the United States worked independently to combine modulated ligh
40、t and a scanning wheel to reconstruct a scene in line-by-line sweeps. In 1925, Baird succeeded in transmitting a recognizable image.Philo T. Farnsworth, a 21-year-old inventor from Utah, patented a scanning cathode ray tube, and Vladimir Zworykin of RCA devised a superior television camera in 1930.
41、Regularly scheduled broadcasts started shortly thereafter, and by the early 1940s there were 23 television stations in operation throughout the United States.Shortly after World War , televisions began to appear on the market. The first pictures were faded and flickering, but more than a million set
42、s were sold before the end of the decade. An average set cost $500 at a time when the average salary was less than $3,000 a year. In 1950 engineers perfected the rectangular cathode-ray tube and prices dropped to $200 per set. Within 10 years 45 million units were sold.A study of how human vision wo
43、rks enabled engineers to develop television technology. Images are retained on the retina of a viewers eye for a fraction of a second after they strike it. By displaying images piece by piece at sufficient speed, the illusion of a complete picture can be created. By changing the image on the screen
44、25 to 30 times per second, movement can be realistically represented. Early scanning wheels slowly built a picture line by line. In contrast, each image on a modem color television screen is comprised of more than 100,000 picture elements (pixels), arranged in several hundred lines. The image displa
45、yed changes every few hundredths of a second. For a 15-minute newscast, the television must accurately process more than 1 billion units of information. Technical innovations that made this possible included a screen coated with millions of tiny dots of fluorescent compounds that emit light when str
46、uck by high-speed electrons.Today this technology is in transition again, moving away from conventional television waves and on to discrete digital signals carried by fiber optics. This holds the potential for making television interactive-allowing a viewer to play a game or order action replays. Ca
47、thode ray tubes with power-hungry electron guns are giving way to liquid crystal display (LCD) panels. Movie-style wide screens and flat screens are readily available. Digital signals enable High Definition Television (HDTV) to have almost double the usual number of pixels, giving a much sharper pic
48、ture. The advent of cable television and advances in fiber-optic technology will also help lift the present bandwidth restrictions and increase image quality.（分数：10.00）(1).According to the passage, entertainment coverage was extended by _.（分数：1.00）A.the speakers and the screensB.early and late editi
49、ons of newspapersC.live sports broadcasts and live performancesD.cultural performances(2).Guglielmo Marconi is the main person who applied _ into practical devices.（分数：1.00）A.the theories of radio wavesB.electromagnetic signalsC.the Tesla coilD.wireless telegraph(3).With the diode invented by Sir John Ambrose Fleming, electric current can _.（分数：1.00）A.be developed into an oscillating signalB.produce the radioC.turn live voice broadcasting into realityD
