时差N小时 为什么我们需要睡眠?(上)（在线收听）

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 for centuries, 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 it and 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-being.

我们知道长期失眠会严重地危害健康，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 toxins 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。