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Losing your ability to think and remember is pretty scary. We know the riskof dementia (痴呆) increases with age. But if you have memory slips, you probablyneedn’t worry. There are pretty clear differences between signs of dementia andage-related memory loss.

After age 50, it’s quite common to have trouble remembering the names ofpeople, places and thing quickly, says Dr. Kirk Daffner of Brigham and Woman’sHospital in Boston.

The brain ages just like the rest of the body. Certain parts shrink,especially areas in the brain that are important to learning, memory andplanning. Changes in brain cells can affect communication between differentregions of the brain. And blood flow can be reduced as blood vessels narrow.

Forgetting the name of an actor in a favorite movie, for example, isnothing to worry about. But if you forget the plot of the movie or don’tremember even seeing it, that’s far more concerning, Daffner says.

When you forget entire experiences, he says, that’s “a red flag thatsomething more serious may be involved.” Forgetting how to operate a familiarobject like a microwave oven, or forgetting how to drive to the house of afriend you’ve visited many times before can also be signs of something goingwrong.

But even then, Daffner says, people shouldn’t panic. There are many thingsthat can cause confusion and memory loss, including health problems liketemporary stoppage of ……

Defense against memory loss is to try to prevent it by building up yourbrain’s cognitive (认知的) reserve, Daffner says.

“Read books, go to movies, take on new hobbies or activities that force oneto think in novel ways,” he says. In other words, keep your brain busy andworking. And also get physically active, because exercise is a known brainbooster.

46. Why does the author say that one needn’t be concerned about memoryslips?

A) Not all of them are symptoms of dementia.

B) They occur only among certain groups of people.

C) Not all of them are related to one’s age.

D) They are quite common among fifty-year-olds.

47. What happens as we become aged according to the passage?

A) Our interaction skills deteriorate.

B) Some parts of our brain stop functioning.

C) Communication within our brain weakens.

D) Our whole brain starts shrinking.

48. Which memory-related symptom should people take seriously?

A) Totally forgetting how to do one’s daily routines.

B) Inability to recall details of one’s life experiences.

C) Failure to remember the names of movies or actors.

D) Occasionally confusing the addresses of one’s friends.

49. What should people do when signs of serious memory loss show up?

A) Check the brain’s cognitive reserve. C) Turn to a professional forassistance.

B) Stop medications affecting memory. D) Exercise to improve theirwell-being.

50. What is Dr Daffner’s advice for combating memory loss?

A) Having regular physical and mental checkups.

B) Taking medicine that helps boost one’s brain.

C) Engaging in known memory repair activities.

D) Staying active both physically and mentally.

答案解析：

Passage One

46. 答案A

解析：根据定位词needn’t be concerned和memory slips定位到第一段第三和第四句，原文there are prettyclear differences between signs of dementia and age-related memoryloss与A选项意思一致。其他三个选项均不符题意。

47. 答案C

解析：根据定位词become aged定位到第三段，原文changes in brain cells can affect communicationbetween different regions of the brain与C选项意思一致。其他三个选项均不符题意。

48. 答案A

解析：根据定位词take seriously定位到第五段，原文more serious与定位词匹配，entireexperience与A选项意思一致。其他三个选项均不符题意。

49. 答案A

解析：根据定位词signs of serious memory loss show up定位到倒数第二段最后一句，原文brain cognitivereserve与A选项意思一致。其他三个选项均不符题意。

50. 答案D

解析：根据定位词Dr. Daffner’s advice定位到最后一段最后两句话，原文get physicallyactive与D选项意思一致。其他三个选项均不符题意。