英语听力文摘 English Digest 307、选择性记忆删除

　　Selective Memory Erasure¹
选择性记忆删除
Ya?l: Have any unpleasant memories, Don?
Don: Sure. Who doesn't?
Y: What would you say to having them permanently² erased⁴ from your brain?
D: Without losing other memories?
Y: Right. Scientists did just that with rats. They trained rats to fear two different sounds by sending a mild electric shock through the rats' paws when they played the sounds. This Pavlovian technique resulted in the rats freezing up in nervous  anticipation⁵ of the shocks every time they heard either sound. Scientists wanted to know whether they could erase³ one of the memories without erasing⁶ the other one, even though both sounds result in the same fear.
D: I didn't know scientists knew how to erase memories at all.
Y: They do. You see, long-term memories aren't nearly as solid as we like to think. They're actually very fragile. Every time we recall a long-term memory, it becomes malleable⁷. Just before playing one of the sounds, scientists injected half the rats with a chemical that interferes⁸ with memory reconsolidation. Thus, when they were in the process of remembering what accompanies the sound, the drug went to work.
D: Then what?
Y: When they played both sounds a day later, the rats that had been injected with the chemical did not freeze up when they heard the sound that had accompanied the drug. They froze as usual when they heard the second sound.
D: They had forgotten to be afraid. Hmm. This business makes me kind of nervous.
Y: I know what you mean, but for people with post-traumatic stress disorder⁹, selective memory erasure could prove enormously useful.
D: True. I guess some fears are best laid to rest.

　　Y: 你有过不愉快的记忆吗，唐？
D: 当然有，每个人都有的。
Y: 如果把它们永远从你的大脑里删除，你觉得怎么样？
D: 不丧失其他记忆？
Y: 是的。科学家们用老鼠做了实验。他们先训练老鼠对两种不同的声音产生恐惧。当他们播放声音的时候轻度电击老鼠的爪子。这种巴普洛夫技术产生了这种结果：每次老鼠听到其中一种声音就会怕被电击而变得非常紧张。科学家想知道他们能否将删除老鼠对其中一种声音的恐惧，而且要保留另外一组记忆。尽管两种声音都会让老鼠产生恐惧。
D: 我不知道科学家们如何删除记忆。
Y: 他们可以的。要知道，长期性记忆并非我们想象的那么牢固。实际上它们是很容易被破坏的。每当我们回忆起一段长期记忆，它都是具有可塑性的。在播放声音之前，科学家先给老鼠注射一种干扰再次巩固记忆的药物。因此，当它们在回忆声音的过程中，药物就起作用了。
D:然后呢？
Y:当他们播放两种声音一天后，再给老鼠注射注射一种药物，让它们在听到声音的同时不再害怕。而听到第二种声音的时候还是会害怕。
D:它们就会忘记害怕。嗯，这样的实验让我有点紧张。
Y:我知道你的意思，但对那些外伤后应激障碍的人来说，选择性记忆删除会起到非常大的作用。
D:是的，我想有些恐惧最好将它们埋葬。

1 erasure   

n.擦掉，删去；删掉的词；消音；抹音

参考例句：

• The past was erased, the erasure was forgotten, the lie became truth. 过去给人擦拭个干净，擦拭的行为又忘了个干净，于是，谎言就变成了真理。 来自英汉文学
• The inspection, modification, replacement or erasure of part of file's contents. 检查、修改、代替或擦去文档内容一部分的过程。 来自互联网

2 permanently   

adv.永恒地，永久地，固定不变地

参考例句：

• The accident left him permanently scarred.那次事故给他留下了永久的伤疤。
• The ship is now permanently moored on the Thames in London.该船现在永久地停泊在伦敦泰晤士河边。

3 erase   

v.擦掉；消除某事物的痕迹

参考例句：

• He tried to erase the idea from his mind.他试图从头脑中抹掉这个想法。
• Please erase my name from the list.请把我的名字从名单上擦去。

4 erased   

v.擦掉( erase的过去式和过去分词 )；抹去；清除

参考例句：

• He erased the wrong answer and wrote in the right one. 他擦去了错误答案，写上了正确答案。 来自《简明英汉词典》
• He removed the dogmatism from politics; he erased the party line. 他根除了政治中的教条主义，消除了政党界限。 来自《简明英汉词典》

5 anticipation   

n.预期，预料，期望

参考例句：

• We waited at the station in anticipation of her arrival.我们在车站等着，期待她的到来。
• The animals grew restless as if in anticipation of an earthquake.各种动物都变得焦躁不安，像是感到了地震即将发生。

6 erasing   

v.擦掉( erase的现在分词 )；抹去；清除

参考例句：

• He was like a sponge, erasing the past, soaking up the future. 他象一块海绵，挤出过去，吸进未来。 来自辞典例句
• Suddenly, fear overtook longing, erasing memories. 突然，恐惧淹没了渴望，泯灭了回忆。 来自辞典例句

7 malleable   

adj.(金属)可锻的;有延展性的；(性格)可训练的

参考例句：

• Silver is the most malleable of all metals.银是延展性最好的金属。
• Scientists are finding that the adult human brain is far more malleable than they once thought.科学家发现成人大脑的可塑性远超过他们之前认识到的。

8 interferes   

vi. 妨碍，冲突，干涉

参考例句：

• The noise interferes with my work. 这噪音妨碍我的工作。
• That interferes with my plan. 那干扰了我的计划。

9 disorder   

n.紊乱，混乱；骚动，骚乱；疾病，失调

参考例句：

• When returning back,he discovered the room to be in disorder.回家后，他发现屋子里乱七八糟。
• It contained a vast number of letters in great disorder.里面七零八落地装着许多信件。