Section C
Directions: There are 2 passages in this section. Each passage is followed by some questions or unfinished statements. For each of them there are four choices marked A), B), C) and D). You should decide on the best choice and mark the corresponding letter on Answer Sheet 2 with a single line through the centre.
Passage One
Questions 46 and 50 are based on the following passage.
Losing your ability to think and remember is pretty scary. We know the risk of dementia (痴呆症) increases with age. But if you have memory slips, you probably needn't worry. There are pretty clear differences between signs of dementia and age-related memory loss.
After age 50, it's quite common to have trouble remembering the names of people, places and things quickly, says Dr. Kirk Daffner of Brigham and Women's Hospital 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 and planning. Changes in brain cells can affect communication between different regions 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, is nothing to worry about. But if you forget the plot of the movie or don't remember even seeing it, that's far more concerning, Daffner says.
When you forget entire experiences, he says, that's "a red flag that something more serious may be involved." Forgetting how to operate a familiar object like a microwave oven, or forgetting how to drive to the house of a friend you've visited many times before can also be signs of something going wrong.
But even then, Daffner says, people shouldn't panic. There are many things that can cause confusion and memory loss, including health problems like temporary stoppage of breathing during sleep, high blood pressure, or depression, as well as medications (药物) like antidepressants.
You don't have to figure this out on your own. Daffner suggests going to your doctor to check on medications, health problems and other issues that could be affecting memory. And the best defense against memory loss is to try to prevent it by building up your brain's cognitive (认知的) reserve, Daffner says.
"Read books, go to movies, take on new hobbies or activities that force one to think in novel ways," he says. In other words, keep your brain busy and working. And also get physically active, because exercise is a known brain booster.
46.Why does the author say that one needn't be concerned about memory slips?
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.
B.Stop medications affecting memory.
C.Turn to a professional for assistance.
D.Exercise to improve their well-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：
46. 根据“There are pretty clear differences between signs of dementia and age-related memory loss.”以及后文举例说明并非所有记忆下滑都是痴呆症症状，可知并非所有记忆下滑都是痴呆症的症状，所以不必担心，所以选A。
47. 根据“Changes in brain cells can affect communication between different regions of the brain.”可知随着年龄增长，大脑内细胞变化会影响大脑不同区域间的交流，即大脑内部交流减弱，所以选C。
48. 根据“When you forget entire experiences, he says, that's 'a red flag that something more serious may be involved.'”可知完全忘记如何做日常事务是严重的记忆相关症状，应认真对待，所以选A(Totally forgetting how to do one's daily routines. 是When you forget entire experiences的同义转述)。
49. 根据“Daffner suggests going to your doctor to check on medications, health problems and other issues that could be affecting memory.”可知当出现严重记忆丧失迹象时，应寻求专业人士帮助，所以选C。
50. 根据“'Read books, go to movies, take on new hobbies or activities that force one to think in novel ways,' he says. In other words, keep your brain busy and working. And also get physically active, because exercise is a known brain booster.”可知Daffner博士建议对抗记忆丧失的方法是保持身心活跃，所以选D。
