考满分 toefl

1 .Listen to part of a lecture in a psychology class.

请听心理学课上的一段讲座内容。

1 .P: Okay, today I'd like to continue our discussion of the human nervous system. We've said that the nervous system is essentially a network of specialized cells called neurons. And we said that the primary function of neurons is to relay signals from one part of the body to another.

教授：好的，今天我们继续讨论人类神经系统。我们之前讲过，神经系统本质上是由称为神经元的特化细胞构成的网络。我们还提到，神经元的主要功能是将信号从身体的一部分传递到另一部分。

1 .Now, neurochemicals are chemicals that are produced by the body that influence neuron function. One very important neurochemical is dopamine. Several decades ago, it was learned that dopamine is related to the experience of pleasure. For a long time, researchers theorized that dopamine actually produced pleasure. That's because researchers found that when the animals they studied received a reward or even simply anticipated a reward, a release of dopamine was triggered in their brain. So it was quite logical to think that it was dopamine that produced a sense of pleasure in animals when they obtain a reward.

神经化学物质是身体产生的影响神经元功能的化学物质。一种非常重要的神经化学物质是多巴胺。几十年前，人们发现多巴胺与愉悦体验有关。长期以来，研究人员认为多巴胺实际上会产生愉悦感。这是因为研究人员发现，当他们研究的动物获得奖励，甚至只是预期会获得奖励时，大脑中就会触发多巴胺的释放。因此，人们很自然地认为，动物在获得奖励时的愉悦感是由多巴胺产生的。

1 .Okay, but more recent research suggests that dopamine doesn't actually produce pleasure. Instead, it increases the expectation of pleasure, so the higher the level of dopamine in an animal's brain, the more pleasure the animal expects to get when it obtains a certain reward, whether or not the animal will actually experience pleasure when it obtains that reward is another story. The actual sensation of pleasure itself appears to be produced by other neurochemicals.

但是，最近的研究表明，多巴胺实际上并不产生愉悦感，而是增加对愉悦的预期。因此，动物大脑中的多巴胺水平越高，它们在获得某种奖励时预期的愉悦感就越强。不过，动物在获得奖励时是否真的会体验到愉悦感则是另一回事，真正的愉悦感似乎是由其他神经化学物质产生的。

1 .Okay, now that's in research animals, but it's thought that dopamine serves a similar function in the human brain. And we think dopamine may play an important role in human decision making. How might that work? Any ideas? John?

以上是在研究动物中的发现，但人们认为多巴胺在人类大脑中具有类似的功能。我们认为多巴胺可能在人类决策中发挥重要作用。这是如何运作的呢？有什么想法吗？约翰？

1 .S: Hum... P: Okay, how do we make decisions? S: Uh... P: Okay, imagine yourself sitting in a restaurant. S: Okay. P: And you're trying to decide whether you want to have spaghetti or pizza. S: Okay. P: How do you decide? S: Well, I kind of imagine what it would be like to be eating the spaghetti, you know, how it would taste and smell? P: Okay. S: Then I imagine what it'd be like to be eating the pizza. P: Okay. S: Then I pick whichever one I think I'm going to enjoy the most. P: Okay! That's what we usually do! We picture our various options in our mind, and we estimate how we're gonna feel if we choose this option, and how we're going to feel if we choose that option.

学生：嗯…… 教授：好的，我们如何做决定呢？ 学生：呃…… 教授：假设你坐在一家餐厅里。 学生：好的。 教授：你在纠结要选意大利面还是披萨。 学生：好的。 教授：你会怎么选？ 学生：嗯，我会先想象吃意大利面的感觉，比如它的味道和气味？ 教授：好的。 学生：然后再想象吃披萨的感觉。 教授：好的。 学生：然后选我觉得最可能喜欢的那个。 教授：对！我们通常就是这样做的！我们在脑海中想象各种选项，然后估计选择这个选项会有什么感觉，选择那个选项又会有什么感觉。

1 .And researchers now believe that what happens is the brain keeps a record of our past experiences of which experiences produce pleasure and how much pleasure they produced. And then when we're in the process of making a decision and we're picturing one of our options in our mind, if our brain associates that option with pleasurable experiences in our past, it's gonna release dopamine.

研究人员现在认为，大脑会记录我们过去的经历，包括哪些经历带来了愉悦感以及愉悦感的程度。当我们在做决定的过程中，脑海中想象某个选项时，如果大脑将该选项与过去的愉悦经历联系起来，就会释放多巴胺。

1 .And what does the dopamine do? It gives us the feeling that choosing that option will result in a positive outcome. And that's the option we should choose. You ever have to make an important decision, and it's really complicated, and logically, it's really hard to figure out what to do? But you have this intuitive sense, this gut feeling telling you which course of action to take. Well, based on these research findings, I wouldn't be surprised if that was actually dopamine at work and I don't know about you, but when I get one of those gut feelings, I trust it, completely.

多巴胺的作用是什么呢？它会让我们觉得选择那个选项会带来积极的结果，因此我们应该选择那个选项。你有没有过这样的经历：需要做出一个重要决定，情况非常复杂，从逻辑上很难判断该怎么做，但你有一种直觉，一种内心的感觉告诉你该采取什么行动。根据这些研究发现，我认为这种直觉很可能是多巴胺在起作用。不知道你们怎么想，但我完全信任这种直觉。

1 .In fact, it turns out that dopamine may actually play a role in the survival of the human species. Any idea why that might be? Okay, well, let's think about it. The more pleasure we expect to get from something, the... S: Harder we'll try to get it?

教授：事实上，多巴胺可能对人类物种的生存也发挥了作用。为什么会这样呢？我们来想一想：我们预期从某事物中获得的愉悦感越多，就会…… 学生：越努力去获得它？

1 .P: That's right! And dopamine increases the amount of pleasure we expect to get from something. So it motivates us to make the effort we need to work hard to get it. In terms of species survival, what's the one thing humans need to survive? S: Food? P: Right! And dopamine helps motivate us to do what we need to do to get our food. And without dopamine? S: Maybe people wouldn't have been motivated to work for the food they need? P: That's right! Work isn't always fun, but because of dopamine and the expectation of reward that it produces, in this case, food, people are motivated to do things they might otherwise not want to do.

教授：没错！多巴胺会增加我们对某事物的愉悦预期，从而激励我们付出努力去争取它。从物种生存的角度来看，人类生存最需要的东西是什么？ 学生：食物？ 教授：对！多巴胺帮助激励我们去做获取食物所需的事情。如果没有多巴胺呢？ 学生：也许人们就不会有动力去为获取所需的食物而努力？ 教授：没错！工作并不总是有趣的，但由于多巴胺和它产生的对奖励（在这里是食物）的预期，人们会被激励去做那些原本可能不想做的事情。