We may all have had the embarrassing moment：Getting half­way through a story only to realize that we've told this exact tale before to the same  person. Why do  we  make  such  memory mistakes?

According to the research published in Psychological Science, it may have to do with the way our brains process different types of memory.

Researchers Nigel Gopie, of the Rotman Research Institute in Toronto, and Colin Macleod, of the University of Waterloo, divided memory into two kinds. The first was source memory，or the ability to keep track of where information is coming from. The second was destination memory，or the ability to recall who we have given information to.

They found that source memory functions better than destination memory, in part because of the direction in which that information is travelling.

To study the differences between source memory and destination memory, the researchers did an experiment on 60 university students, according to a New York Times report. The students were asked to associate (联想) 50 random(随意的) facts with the faces of 50 famous people. Half of the students“told”each fact to one of the faces, reading it aloud when the celebrity's(名人的) picture appeared on a computer screen. The other half read each fact silently and saw a different celebrity picture afterward.

When later asked to recall which facts went with which faces, the students who were giving information out(destination memory)scored about 16 percent lower on memory performance compared with the students receiving information(source memory)．

The researchers concluded that out­going information was less associated with its environmental context (背景)—that is，the person—than was incoming information.

This makes sense given what is known about attention. A person who is giving information, even little facts, will devote some mental resources to thinking about what is being said. Because our attention is limited，we give less attention to the person we are giving information to.

After a second experiment with another group of 40 students, the researchers concluded that self­focus is another factor that undermines destination memory.

They asked half the students to continue giving out random information, while the other told things about themselves. This time around, those who were talking about themselves did 15 percent worse than those giving random information.

“When you start telling these personal facts compared with non­self facts, suddenly destination memory goes down more, suggesting that it is the self­focus component (成分) that's reducing the memory.”Gopie told Live Science.

60．The point of this article is to ________.

A. give advice on how to improve memory

B. say what causes the memory to worsen

C. explain why we repeat stories to those we've already told them to

D. discuss the differences between source memory and destination memory

61．What can we learn from the article?

A. Source memory helps us remember who we have  told the information to.

B. One's limited attention is one of the reasons why those reading aloud to the celebrity's pictures    perform worse on the memory test.

C. Silent reading is a better way to remember information than reading aloud.

D. It tends to be more difficult for people to link incoming information with its environmental context than outgoing information.

62．The underlined word“undermines” probably means________.

A. weakens         B. benefits

C. explains          D. supports

63．What did the scientists conclude from the second experiment?

A. Destination memory is weaker than source memory.

B. Focusing attention on oneself leads to relatively poor source memory performance.

C. Associating personal experience with information helps people memorize better.

D. Self­focus is responsible for the reduction of destination memory.