英语听力文摘 English Digest 175、药物与学习能力

　　When you experience something new, do you know what happens to your brain?
Some of the neurons in your brain build new connections. The brain is rewired, as scientists often put it. Our brains are always changing, in response to new experiences or as a result of learning new information. That’s how we’re able to learn and remember new experiences and information.
However, the brain reacts quite differently when a person is exposed to drugs such as cocaine¹.
Evidence indicates that prior use of some drugs impairs² the brain’s ability to forge new connections between neurons in response to new experiences. Scientists took a bunch of rats and gave some of them either amphetamine or cocaine for twenty days, while giving the others a saline solution for twenty days.
When the twenty days were up, half of the rats were moved from ordinary laboratory cages to fancy new cages equipped with all kinds of bridges, ramps³, tunnels, and other toys. After three and half months the scientists examined all of the rats brains.
They discovered that the saline solution rats that were moved to the new cages had a greater number of neuronal connections than all the other rats, including the drugged rats in the new cages. These findings may aid in explaining some of the behavioral and cognitive⁴ impairments viewed in people who are addicted⁵ to drugs.

1 cocaine   

n.可卡因，古柯碱（用作局部麻醉剂）

参考例句：

• That young man is a cocaine addict.那个年轻人吸食可卡因成瘾。
• Don't have cocaine abusively.不可滥服古柯碱。

2 impairs   

v.损害，削弱( impair的第三人称单数 )

参考例句：

• Smoking impairs our health. 吸烟会损害我们的健康。 来自《简明英汉词典》
• Almost anything that impairs liver function can cause hepatitis. 任何有损于肝功能的因素，几乎都会引起肝炎。 来自辞典例句

3 ramps   

resources allocation and multiproject scheduling 资源分配和多项目的行程安排

参考例句：

• Ramps should be provided for wheelchair users. 应该给轮椅使用者提供坡道。
• He has the upper floor and ramps are fitted everywhere for his convenience. 他住在上面一层，为了他的方便着想，到处设有坡道。

4 cognitive   

adj.认知的，认识的，有感知的

参考例句：

• As children grow older,their cognitive processes become sharper.孩子们越长越大，他们的认知过程变得更为敏锐。
• The cognitive psychologist is like the tinker who wants to know how a clock works.认知心理学者倒很像一个需要通晓钟表如何运转的钟表修理匠。

5 addicted   

adj.沉溺于....的，对...上瘾的

参考例句：

• He was addicted to heroin at the age of 17.他17岁的时候对海洛因上了瘾。
• She's become addicted to love stories.她迷上了爱情小说。