时差N小时 我们为什么需要睡觉?

Dear A Moment of Science,

亲爱的《科学一科》栏目组：

Why do we sleep?

我们为什么需要睡觉？

I know this question has been debated by scientists and philosophers forcenturies, but are there any hard and fast answers?

我知道科学家们和哲学家们就这个问题争论了好几个世纪，但现在有没有确实的，现成的答案？

Good question!

问得好！

First, it's true that scientists have long pondered the mystery of sleep why we do itand why it's necessary.

首先，科学家们长期以来确实在思考睡眠这一谜题，我们为什么需要睡眠，为什么睡眠十分必要？

We know that going without sleep for too long can seriously damage health, so there's good reason to believe that getting enough sleep is important for our well-being¹.

我们知道长期失眠会严重的危害健康，因此，有必要相信保证睡眠充足对健康很重要。

But exactly how and why that's the case is still an open question.

但失眠为什么会影响健康，又是如何影响的，这个问题仍没有答案。

Some research, though, may shed a little light on the problem.

一些研究也许可以稍稍解答这个问题。

For instance, scientists at the University of Rochester Medical Center in New York did a study with mice,

比如，纽约罗切斯特大学医学中心的科学家们用老鼠做了一个研究，

and found that during sleep their brains flush out toxins² that accumulate during the day.

发现老鼠在睡觉时，他们的大脑会排除白天积累的毒素。

More specifically, the study found that sleep sort of changes the brain's cellular³ structure.

更确切的说，该研究发现睡眠在某种程度上改变了大脑的细胞结构。

When the mice were asleep or anesthetized, the researchers found that there was more space between their brain cells,

当老鼠处于睡眠状态或被麻醉是，研究人员发现，他们大脑细胞之间的空间增大了，

allowing a sort of brain plumbing⁴ apparatus⁵ called the glymphatic system to open wide and allow fluid to flow quickly through the brain.

使被称为脑部类淋巴系统的类似排污管道的器官大大的打开，这样脑脊液就能在大脑中快速的流动。

Other studies have shown that toxic⁶ molecules⁷ build up in the space between brain cells.

其他的研究表明，有毒分子在脑细胞的间隙中生成。

Researchers at the University of Rochester found that those molecules vanished faster from the brain when the mice were asleep.

罗切斯特大学的研究人员发现，这些分子在老鼠睡觉时从大脑中消失得更快。

So what does this mean?

所以，这意味着什么呢？

Well, it could give scientists new ways to study and potentially treatbrain disorders⁸,

这意味着通过针对脑部类淋巴系统可以帮助大脑更好的排除脑部毒素，

like Alzheimer's by targeting the glymphatic system and helping⁹ it better flush awaybrain toxins.

使科学家们有新的方法研究并很有可能治好像老年痴呆症这样的大脑疾病。

1 well-being   

n.安康，安乐，幸福

参考例句：

• He always has the well-being of the masses at heart.他总是把群众的疾苦挂在心上。
• My concern for their well-being was misunderstood as interference.我关心他们的幸福，却被误解为多管闲事。

2 toxins   

n.毒素( toxin的名词复数 )

参考例句：

• The seas have been used as a receptacle for a range of industrial toxins. 海洋成了各种有毒工业废料的大容器。
• Most toxins are naturally excreted from the body. 大部分毒素被自然排出体外。 来自《简明英汉词典》

3 cellular   

adj.移动的；细胞的，由细胞组成的

参考例句：

• She has a cellular telephone in her car.她的汽车里有一部无线通讯电话机。
• Many people use cellular materials as sensitive elements in hygrometers.很多人用蜂窝状的材料作为测量温度的传感元件。

4 plumbing   

n.水管装置；水暖工的工作；管道工程v.用铅锤测量（plumb的现在分词）；探究

参考例句：

• She spent her life plumbing the mysteries of the human psyche. 她毕生探索人类心灵的奥秘。
• They're going to have to put in new plumbing. 他们将需要安装新的水管。 来自《简明英汉词典》

5 apparatus   

n.装置，器械；器具，设备

参考例句：

• The school's audio apparatus includes films and records.学校的视听设备包括放映机和录音机。
• They had a very refined apparatus.他们有一套非常精良的设备。

6 toxic   

adj.有毒的，因中毒引起的

参考例句：

• The factory had accidentally released a quantity of toxic waste into the sea.这家工厂意外泄漏大量有毒废物到海中。
• There is a risk that toxic chemicals might be blasted into the atmosphere.爆炸后有毒化学物质可能会进入大气层。

7 molecules   

分子( molecule的名词复数 )

参考例句：

• The structure of molecules can be seen under an electron microscope. 分子的结构可在电子显微镜下观察到。
• Inside the reactor the large molecules are cracked into smaller molecules. 在反应堆里，大分子裂变为小分子。

8 disorders   

n.混乱( disorder的名词复数 )；凌乱；骚乱；（身心、机能）失调

参考例句：

• Reports of anorexia and other eating disorders are on the increase. 据报告，厌食症和其他饮食方面的功能紊乱发生率正在不断增长。 来自《简明英汉词典》
• The announcement led to violent civil disorders. 这项宣布引起剧烈的骚乱。 来自《简明英汉词典》

9 helping   

n.食物的一份&adj.帮助人的，辅助的

参考例句：

• The poor children regularly pony up for a second helping of my hamburger. 那些可怜的孩子们总是要求我把我的汉堡包再给他们一份。
• By doing this, they may at times be helping to restore competition. 这样一来, 他在某些时候,有助于竞争的加强。