VOA慢速英语2014 睡眠时大脑并未停止工作（在线收听）

While You Sleep, Your Brain Works 睡眠时大脑并未停止工作

From VOA Learning English, this is the Health Report.

Why do we need sleep?

为什么人们需要睡眠？

Is bedtime just a time for dreaming?  Do our brains turn off for the night?  What if I told you that scientists recently discovered that our brains may be just as busy at night as they are during the day?

睡眠时间仅仅是为了做梦吗？睡觉时，大脑依旧在工作吗？如果我告诉你，据科学家最新发现，人类的大脑在夜晚与白天一样忙碌的话，你相信吗？

While we sleep, our brains are doing much more than getting ready for the next day.  Researchers at the University of Rochester found that the brain may be busy cleaning house -- cleaning out harmful waste materials.  

当我们在睡觉时，大脑不仅仅是在为次日做好准备。罗切斯特大学的科学家研究发现，睡眠时大脑可能是忙着打扫，将大脑中的有害废物清理出去。

As with many studies, the researchers turned to mice for help.  They studied mice that had colored dye injected into their brains.  They observed the mice brains as they slept and when they were awake.  The researchers say they saw that the brains of sleeping mice were hard at work. 

当你睡眠时，大脑并未停止工作。正如许多的实验一样，科学家利用老鼠来完成本项研究。试验中，他们将颜色的染料注射到老鼠的大脑来进行观察。当人类清醒时，老鼠却恰好在沉睡，这时正是观察他们大脑的好时机。研究人员表明，他们看到了沉睡时的老鼠大脑还是在努力工作。

Working Double Duty

工作的双重职责

Dr. Maiken Nedergaard led the study.  The brain expert says our brains perform two very different jobs.  It seems they have daytime jobs.  Later they “moonlight” at a nighttime job. 

Maiken Nedergaard博士实施了本次试验。这位脑科专家介绍，我们的大脑从事两份完全不同的工作：实际上，他们有白天的工作，之后他们又“兼职”完成夜间的工作。

“Moonlighting” is working a nighttime job in addition to a day job.  And this study says that is what our brains seem to be doing – working an extra job at night without additional pay for overtime. 

这份兼职的夜间工作是在对日常的工作进行补充。从这份研究，我们可以了解到大脑在夜间似乎在进行一项没有任何加班报酬的额外工作。

“When we are awake, the brain cells are working very hard at processing all the information about our surroundings.  Whereas when we are asleep, they work very, very hard at removing all the waste that builds up when we are awake."

“当我们清醒时，脑细胞正在非常努力地处理所有关于我们周围环境的信息。而当我们都睡着了，他们还要更加努力地去除所有当我们清醒时运转所生成的各种废物。”

The researchers say that the waste material includes poisons, or toxins, responsible for brain disorders such as Alzheimer’s disease.  

研究人员称，该废物包含毒物，或毒素，这些毒素或可诱发各类大脑疾病如阿尔茨海默氏病。

They also found that during sleep, the brain’s cells shrink, or become smaller.  This shrinking permits waste to be removed more effectively.            

他们还发现，在睡眠时，脑细胞会收缩变小，这种收缩可保证大脑能更有效地清除废物。

Dr. Nedergaard says these toxins end up in the liver.  There, they are broken down and then removed from the body.

Nedergaard 博士还指出，这些毒素最终会被运送到肝脏。在那里，他们将会被分解，最终排出体外。

"So our study suggests we need to sleep because we have a macroscopic cleaning system that removes many of the toxic waste products from the brain."

“因此，研究结果表明，人类需要睡眠，是因为我们有一个宏观的清洁系统，能够消除许多大脑中的有毒废物。”         

The brain’s cleaning system could only be studied with new imaging technologies.  The test animal must be alive in order to see for this brain process to be seen as it happens.

大脑的清洗系统只能利用新的成像技术来进行研究。试验动物必须是活体，这样才能观察到整个大脑的运作过程。

Dr. Nedergaard says the next step is to look for the process in human brains.  She said the results demonstrate just how important sleep is to health and fighting disease.  The research may also one day lead to treatments to prevent or help fight neurological disorders.

Nedergaard博士说，实验的下一步是研究人类大脑的运作过程。她说，实验结果不仅仅证明睡眠对于人类健康及对抗疾病有多么重要，也许，这项研究还可能会促使人们研究出防止或有助于对抗神经系统疾病的治疗方法。

7 Tips for Better Sleeping

保证良好睡眠的七大良方

Do you have trouble sleeping?  Not being able to sleep is called insomnia.  According to the United States National Sleep Foundation, here are some tips for a good night’s sleep:

你有睡眠问题？不能入睡被称之为失眠。美国国家睡眠基金会曾提出如下几条保证睡眠的七大良方：

Go to bed about the same time each night, even on weekends.  This helps to “set” your body’s “sleep clock.”

每晚坚持在同一时间上床，即使是在周末，这有助于设定你身体的睡眠时间。

Exercise every day. 

坚持每天锻炼。

Have a calm, relaxing bedtime routine – Take a warm bath or drink a hot cup of tea.

保证就寝前放松、平静的心态，可以洗个热水澡或者喝一杯热奶茶。

 Try not to take long naps during the day.  Periods of sleep during the daytime can interfere with sleep at night. 

尽量不要在白天进行过长时间的午睡。白天的睡眠会对晚休有一定的干扰。

 Make sure you have a pleasant environment where you sleep.  For most people, a cool, quiet and dark room is best for sleeping.

请确保良好的睡眠环境，对于大多数人来说，凉爽、干净、黑暗的房间最适合睡觉。

Avoid using television, computers and other electronic screens before bedtime. 

尽量不在睡前观看电脑、电视，或使用其他电子产品。

Also avoid alcohol, cigarettes and heavy meals before bedtime.

睡前也要避免吸烟、喝酒、或过量进食。

And from VOA Learning English,  that’s the Health Report.  I’m Anna Matteo.

Do you suffer from insomnia?  Do you have more suggestions for a good night's sleep.  Let us know in our comment section.

你失眠吗？如果你对于保证良好睡眠有更多的好方法，请在评论处与大家分享，让我们知晓。