4.The Dyson vacuum cleaner was invented with the purpose of________.

A.helping people use cleaners more easily

B.making Dyson a rich businessman

C.keeping the house cleaner than before

D.taking the place of human cleaners

B

(2013•山西省六所重点中学联考)

What happens inside the skull of a soccer player who repeatedly heads a soccer ball?That question motivated a challenging new study of the brains of experienced players that has caused discussion and debate among socce r players，and some anxiety among those of us with soccer-playing children.

For the study，researchers at the Albert Einstein College of Medicine in New York selected 34 adults，men and women.All of the volunteers had played soccer since childhood and now competed year-round in adult soccer leagues.Each filled out a detailed questionnaire developed especia lly for this study to determine how many times they had headed a soccer ball in the previous year，as well as whether they had experienced any known concussions (脑震荡) in the past.

Then the players completed computerized tests of their memory and other learning skills and had their brains scanned，using a complicated new MRI technique which can find structural changes in the brain that can’t be seen during most sc ans.

According to the data they presented at a Radiological Society of North America meeting last month，the researchers found that the players who had headed the ball more than about 1,100 times in the previous 12 months showed significant loss of white matter in parts of their brains involved with memory，attention and the processing of visual information，compared with players who had headed the ball fewer times.

This pattern of white matter loss is “similar to those seen in traumatic (外伤的) brain injury”，like that after a serious concussion，the researchers reported，even though on ly one of these players was reported to have ever experienced a concussion.

The players who had headed the ball about 1,100 times or more in the past year were also generally worse at recalling lists of words read to them，forgetting or fumb ling the words far more often than players who had headed the ball less.

5.The passage is most probably a________.

A.news report 　　 B.research report

C.story for soccer players　　 D.text for doctors

6.From the passage we can conclude that frequent heading may have________.

A.significant effect on one’s brain

B.little effect on one’s brain

C.nothing to do with the brain injury

D.one’s memory improved

7.What is likely to be the cause of memory loss?

A.Playing soccer frequently.

B.Tests of their memory.

C.White matter loss.

D.Information processing.

8.The underlined word “fumbling” is closest in meaning to________.

A.remembering 　　 B.misunderstanding

C.recalling 　　 D.missing