刘爽

“Sleep is your life-support system and Mother Nature's best effort”， says sleep scientist Matt Walker. In this speech， Walker shares the wonderfully good things that happen when you get sleep —— and the alarmingly bad things that happen when you don't， for both your brain and body. Read this passage and learn more about sleep's effect on your learning， memory， immune system —— as well as some helpful tips for getting some good sleep.

“睡眠是你的生命保障系统，也是大自然的伟大成果”，睡眠专家迈特·沃克如是说。在这篇演讲中，沃克分享了睡眠对大脑和身体的影响。当你睡觉时，会有极好的事发生;而当你不睡觉时，令人担忧的坏事也会发生。读一下这篇文章，了解更多关于睡觉对学习、记忆力、免疫系统的影响，还可以获得一些关于良好睡眠的建议。

I would like to start with the brain and the functions of learning and memory， because what we've discovered over the past 10 years is that you need sleep after learning to save those new memories so that you don't forget. But recently， we discovered that you also need sleep before learning to prepare your brain， almost like a dry sponge ready to soak up new information. And without sleep， you can't absorb new memories.

我想从大脑，以及学习和记忆的功能开始讲起，因为我们在过去十年中发现，学习之后需要睡觉，这样你才不会遗忘。但是最近，我们发现在学习之前也需要睡眠，这样才能准备好自己的头脑，就像是一块干海绵准备好吸收新的知识。没有睡眠的话，你无法吸收新的记忆。

In a study， we took a group of individuals and we assigned them to two experimental groups： a sleep group and a sleep deprivation group. Now the former group， they're going to get a full eight hours of sleep; but the latter， we're going to keep them awake in the laboratory. There's no naps or caffeine， so it's miserable for everyone involved. And then the next day， we're going to place those participants inside an MRI scanner and we're going to have them try and learn a whole list of new facts as we're taking photos of brain activity. And then we're going to test them to see how effective that learning has been. When you put those two groups together， what you find is a quite significant， 40-percent decrease in the ability of the brain to make new memories without sleep.

在這个研究中，我们招募了一组人员，然后将其分到两个实验组：充足睡眠组和剥夺睡眠组。前一个小组的被试者可以睡够八个小时，而后一个小组的被试者会在实验室中一直保持清醒。他们不能小憩，也没有咖啡，所以每个人都很痛苦。第二天，我们把这些被试者放进核磁共振扫描仪，让他们试着学习一整列新知识，同时，会将他们的大脑活跃情况拍摄下来。之后，我们测试他们，来看看他们的学习到底有没有效果。当你把两组照片放在一起比较，你可以发现区别很明显，没有充足睡眠的大脑，储存新记忆的能力会下降40%。

So that's the bad that can happen if I were to take sleep away from you， but let me just come back to that sleep group. Do you remember those individuals that got a full eight hours of sleep？ Well， we can ask a very different question： What is it about the physiological quality of your sleep when you do get it that restores and enhances your memory and learning ability each and every day？ And by testing and studying， what we've discovered is that there are big， powerful brainwaves that happen during the very deepest stages of sleep. And it's the combined quality of these deep-sleep brainwaves that acts like a file-transfer mechanism at night， shifting memories from a short-term vulnerable storage to a more permanent long-term one within the brain， and therefore protecting them， making them safe. And it is important that we understand what during sleep actually transacts these memory benefits， because there are real medical and societal effects.

所以，假如我剥夺你的睡眠，一些糟糕的事情就会发生。但容我稍微讲一下睡眠组。你们还记得那些睡够了八个小时的人吗？我们可以问一个不同的问题：是什么东西决定了你睡觉以后的睡眠质量，让你每天都能够强化记忆并且恢复学习能力？通过测试和研究，又强又剧烈的脑电波会发生在深度睡眠阶段。正是这些深度睡眠脑电波的综合作用，在夜间起到了文件传输机制的作用，将记忆从一个短期的、易受遗忘的存储库转移到大脑中一个更永久的长期存储库，因此得以保存它们，使它们不受损。重要的是，我们要了解在睡眠中究竟是什么在发挥这些记忆的作用，因为这对医学和社会都有实际的影响。

And let me just tell you about one area that we've moved into. That is aging and Alzheimers disease. Because it's no secret that， as we get older， our learning and memory abilities begin to fade and decline. But what we've also discovered is that a physiological signature of aging is that your sleep gets worse， especially that deep quality of sleep. And only last year， we finally published evidence that these two things， they're not simply occurring together， they are significantly interrelated. And it suggests that the disruption of deep sleep is an important factor that is contributing to cognitive decline or memory decline in aging， and most recently we've discovered， in Alzheimer's disease as well.

让我告诉大家，我们已经把这项研究转移到另一个领域了，即衰老和阿尔茨海默症。因为随着我们变老，我们的学习和记忆能力开始衰退和减弱，这当然不是什么秘密。但我们也发现衰老的一个生理特征是你的睡眠质量变差了，尤其是深度睡眠质量。在去年，我们终于发现了证据来表明这两件事不是单纯的同时发生，而是明显相互关联的。这就表明，在人们衰老时，深度睡眠的中断是导致认知能力和记忆能力衰退的一个重要因素。最近我们还发现，阿尔茨海默症也是如此。

Next， I want to focus on this： sleep loss and your immune system. And here， I'll introduce natural killer cells first， and you can think of natural killer cells almost like the secret service agents of your immune system. They are very good at identifying dangerous， unwanted elements and getting rid of them. And tragically， you cannot have these cells if you're not sleeping enough.

接下来，我想要着重讨论这点：睡眠的缺失以及你的免疫系统。在这里，我首先介绍自然杀伤细胞，你可以把自然杀伤细胞想象成你免疫系统中的特工。它们非常擅长识别危险和有害的物质，并消灭它们。悲剧的是，当你睡眠不足时，你不能拥有这种细胞。

So here in this experiment， you're not going to have your sleep deprived for an entire night， you're simply going to have 4-hours sleep for one single night， and then we're going to look to see what's the percent reduction in immune cell activity that you suffer. And it's not small —— it's not 10%， it's not 20%. There was a 70% drop in natural killer cell activity. That's a concerning state. Perhaps now you can understand why we're now finding significant links between short sleep duration and your risk for the development of cancer. In fact， the link between a lack of sleep and cancer is now so strong that the World Health Organization has classified any form of nighttime shift work as a probable factor of getting cancer.

所以在這个实验中，你整晚的睡眠不会被全部剥夺，但你一晚仅能睡4个小时。然后我们来看看你的免疫细胞会受到多大比例的影响。这并不是个小数目——不是10%，不是20%。自然杀伤细胞的活力下降率高达70%。这是个令人担忧的状态。或许现在你就能理解为什么我们发现睡眠不足和罹患癌症之间有重要关联。事实上，睡眠不足和癌症之间的联系是如此紧密，以至于世界卫生组织将任何形式的夜班工作列为可能的致癌因素。

And at this point， you may be thinking， "Oh my goodness， how do I start to get better sleep？ What are your tips for good sleep？" Well， beyond avoiding the damaging and harmful impact of alcohol and caffeine on sleep， and if you're struggling with sleep at night， avoiding naps during the day， I have two pieces of advice for you.

此刻，你可能在想：“老天，我怎样才能得到更好的睡眠？你有没有睡个好觉的建议？”好吧，除了避免酒精和咖啡因对睡眠的有害影响，如果你正在与夜晚失眠做斗争，白天也在避免打盹，那么我给你两点建议。

The first is regularity. Go to bed at the same time， wake up at the same time， no matter whether it's the weekday or the weekend. Regularity is king， and it will anchor your sleep and improve the quantity and the quality of that sleep. The second is keep it cool. Your body needs to drop its temperature by about two to three degrees Fahrenheit to start to sleep， and it's the reason you will always find it easier to fall asleep in a room that's too cold than too hot. So the temperature of a bedroom should be around 65 degrees， or about 18 degrees Celsius.

首先是规律。准时上床，准时醒来，不管是工作日还是周末。规律为王，它会保障你的睡眠，并且改善你睡眠的时间长短和质量。第二点是降低温度。你的身体需要把核心温度降低2到3华氏度，才能进入睡眠，这也是为什么你会发现冷的环境要比热的环境容易入睡。所以卧室的温度应该在65华氏度，或者18摄氏度左右。

And then finally， what I want to say is that sleep is not an optional lifestyle. Sleep is an undoubted biological necessity. It is your life-support system， and it is Mother Nature's best effort. And the loss of good sleep in industrial countries is having a terrible impact on our health， even the safety and the education of our children. And it's fast becoming one of the greatest public health challenges that we face in the 21st century.

最后我想说，睡眠并不是一个可选的生活方式。睡眠是一个不容置疑的生理需要。它是你的生命保障系统，是大自然母亲的最佳馈赠。工业化国家睡眠的丢失对我们的健康，对我们的安全，甚至对孩子的教育有糟糕的影响。它正在快速成为21世纪我们所面临的公众健康的最大挑战之一。

（本文摘自TED官网： https：//www.ted.com/talks/matt_walker_sleep_is_your_superpower）

阅读文章后，也尝试找找以下问题的答案吧！

1. What have the researchers recently found about the impact of sleep？

A. We need sleep after learning to save those new memories.

B. We need sleep before learning to get our brain prepared.

C. We cannot learn well without the help of caffeine.

D. We can get new memories even if we do not have enough sleep.

2. Which following statement is true according to the passage？

A. Our brains ability of making memories will decrease 30% if we have a bad sleep.

B. Natural killer cell activity will drop 30% if you sleep 4 hours a day.

C. There is a close relationship between sleep loss and immune system injury.

D. If we lose sleep for one night， we are going to develop cancer.

3. According to the passage， what is the relationship between deep sleep and Alzheimers disease？

A. Lack of deep sleep plays an important role in contributing to the Alzheimers disease.

B. When a person gets Alzheimers disease， he or she cannot get deep sleep.

C. There is no significant relationship between deep sleep and Alzheimers disease.

D. Deep sleep and Alzheimers disease occur simultaneously.

4. What is not Walkers suggestion on sleep？

A. Quit smoking and caffeine.

B. Sleep as regularly as possible.

C. Keep the temperature of the bedroom about 18 degrees Celsius.

D. Getting naps during the day.

參考答案：B C A D