Question

Uh­oh, the new year's just begun and already you're finding it hard to keep those resolutions to junk the junk food，get off the couch or kick smoking. There's a biological reason why a lot of our bad habits are so hard to break—they get deep­rooted in our brains.

That's not an excuse to give up. Understanding how unhealthy behaviors become deep­rooted has scientists learning some tricks that may help good habits replace the bad.“Why are bad habits stronger? You're fighting against the power of an immediate reward. We all as creatures give greater value to an immediate reward than something that's delayed，” says Dr Nora Volkow, director of the National Institute on Drug Abuse.

Just how that bit of happiness turns into a habit involves a pleasure­sensing chemical named dopamine(多巴胺). It trains the brain to want that reward again and again—increasing the connection each time—especially when it gets the right cue(暗示) from your environment.

People tend to overestimate their ability to resist temptations around them, thus destroying attempts to get rid of bad habits. Even scientists who recognize it find it hard to resist.“I don't like popcorn. But every time I go to the cinema, I have to eat it，” Volkow says.“It's fascinating.”

A movement to pay people for behavior changes may make use of that connection, as some companies offer employees immediate payments for adopting better habits. However paying for behavior turns out, researchers say there are some steps that may help counter your brain's hold on bad habits: repeat，repeat，repeat the new behavior—the same routine at the same time of day. Determined to exercise？Doing it at the same time of the morning makes the brain recognize the habit eventually. If you don't do it, you feel awful. Exercise itself raises dopamine levels, so eventually your brain will get a feel­good hit even if your muscles protest. Reward yourself with something you really desire, Volkow stresses. You exercised all week? Stuck to your diet? Buy a book, a great pair of jeans, or try a fancy restaurant.

20．What's the subjective reason for being hard to break bad behaviors?

A．Some behaviors get deep­rooted in our brains.

B．We prefer an immediate reward.

C．We value delayed gifts.

D．We are all creatures of nature.

21．What does the underlined word “connection” in Paragraph 3 refer to?

A．Pleasure and behavior.  　B．Brain and reward.

C．Happiness and dopamine.  　D．Cue and environment.

22．It can be inferred that the higher the dopamine level is，________．

A．the harder it is for you to break the bad habit

B．the less pleasure you will get

C．the stronger bad habits will become

D．the more you'll want to get a reward

23．Why does Volkow eat popcorn even though he doesn't like it?

A．Because he recognizes the importance of him.

B．Because it is needed for normal growth of the body.

C．Because he can't resist the temptation of it.

D．Because it makes him relaxed to eat popcorn while seeing films.

Answer 1

这是一篇科普文。人们在新年到来时常常会下定某些决心，然而却发现很难坚持下去。科学家研究出了一些“技巧”，可以让好习惯取代坏习惯。

20．B　细节理解题。此题应特别注意题干中the subjective reason(主观原因)。根据短文第二段中的“We all as creatures give greater value to an immediate reward than something that's delayed”可知，难以改掉坏习惯在主观上的原因是人们更看重即时的好处。A项有很大的干扰，文章第一段中提到：这些坏习惯根植于我们的大脑中，这是很难改掉坏习惯在生物学上的原因(客观原因)。

21．A　词义猜测题。根据语境：在快乐的感觉转化为一种习惯的过程中，一种感知快乐的化学物质多巴胺在起作用，它不断促使大脑期望得到这种犒赏，并不断加强快乐感与这种行为之间的联系。由此可知，connection指的是“快乐感与行为之间的联系”。

22．D　推理判断题。根据第三段内容可知，多巴胺是一种感知快乐的化学物质，它使大脑不断期望得到某种犒赏。最后一段中的“Exercise itself raises dopamine levels”能进一步证明，多巴胺的水平越高，人们就越想得到某种犒赏。

23．C　细节理解题。根据第四段内容可知，人们往往高估自己抵制身边诱惑的能力，这使他们为摆脱坏习惯而作出的努力毁于一旦。Volkow就是因为抵抗不了这种诱惑才吃爆米花的。