Why Daylight Is the Secret to Great Sleep | Christine Blume | TED

譯者: 麗玲 辛 審譯者: Yanyan Hong

On a usual Saturday, you wouldn't find me here.

通常星期六，你不會在這裡看到我。

And I mean, of course, I don’t give TEDx Talks every Saturday.

當然，我不是每個星期六 都會發表 TEDx 演講。

But what I mean is, you probably wouldn't find me in a museum.

但我的意思是，你可能 不會在博物館看到我。

Rather, if you were looking for me,

如果你想找我，

you'd probably have to go to the mountains,

可能得往山裡去，

and that is because I absolutely love hiking.

因為我熱愛健行。

And in addition to just being outside and being in nature,

除了能待在戶外、親近大自然之外，

what I really like is this feeling of physical exhaustion,

我最喜歡的，就是 那種身體極度疲憊的感覺——

sort of this satisfaction you can feel in every single muscle.

那種每一塊肌肉 都能感受到的滿足感。

And in the evening, when it's time to go to bed,

到了晚上，該睡覺的時候，

I absolutely cherish this amazing sleepiness

那種從頭到腳襲來的濃濃睡意，

that fills you from head to toe.

讓我特別珍惜。

Now you might say, "Well, of course she's tired. She's been hiking all day.

你可能會說：「當然會累啊， 她整天都在健行。

Plus, not to forget about the effects of supposedly fresh air."

而且，別忘了所謂的 『新鮮空氣』效應。」

But there is one factor that most likely outweighs

但其實，有一個因素的影響 可能遠遠超過新鮮空氣，

the effects of fresh air and perhaps even physical activity,

甚至超過體能活動，

and that is exposure to natural daylight.

那就是，接觸到天然的日光。

And today, I hope to convince you that we should all appreciate daylight

而今天，我希望能說服大家，

把日光視為一種天然的助眠劑。

as sort of a natural soporific.

And hopefully, by the end of the talk,

希望在這場演講結束後，

you will also recognize that we should all pay more attention

你也會認同我們應該更加重視

to our daily light diet.

自己的「每日光照攝取量」。

But let's start with the question why daylight is so important

但讓我們從這個問題開始，

為什麼日光對我們的身體、健康， 甚至對睡眠來說，如此重要呢？

for our organism, for health and, eventually, for sleep.

Now throughout your body, in each and every single cell,

其實，我們全身的每一個細胞裡，

there is a tiny molecular clock ticking inside it.

都有一個微小的分子時鐘在滴答作響。

And to keep these millions of clocks in sync,

而為了讓這數百萬個時鐘保持同步，

we have one central body clock that is located in the brain,

我們的大腦裡有一個 「中央生理時鐘」，

位於一個稱為「下視丘」的區域。

in an area which we call the hypothalamus.

And like the conductor of an orchestra,

它就像是樂團的指揮，

it communicates the time of day to each of these molecular clocks.

負責將時間資訊傳達給 所有細胞內的分子時鐘，

And this way, it is able to regulate bodily processes

讓我們的生理運作與外在時間同步。

in sync with the time of day.

For example,

例如，它會在早晨讓體溫上升，

it causes your body temperature to increase in the morning

到了晚上讓體溫下降。

and to decrease in the evening.

It choreographs the release of certain hormones at appropriate times.

它也會在適當的時候 釋放特定的荷爾蒙。

And in the evening, when it’s time to go to bed,

到了夜晚，該睡覺時，

it will also make you tired and sleepy.

它會讓我們感到疲倦與睏意。

But given this precise synchronization between internal or biological time

既然我們的內在生理時鐘

and external time or environmental time,

與外界時間高度同步，

it seems clear that the body clock

顯而易見地，這個生理時鐘

cannot be blind or isolated or shut off from the environment,

不可能是「盲目的」、與環境隔絕的，

必然是接收來自環境的時間資訊，

but rather, it needs to receive information about the time of day

from the environment

for it to synchronize with sun time.

才能與日光時間同步。

And this is achieved by close connections

而這正是透過大腦中的生理時鐘

between the internal biological clock in the brain and our eyes.

與我們眼睛之間的密切聯繫來達成的。

And now you may know that in the human retina,

你可能知道，我們的視網膜中

there are different types of receptors,

其實有不同種類的感受器，

so photoreceptors, so receptors that sense light.

光感受器，也就是感受光的受體。

And classically, we distinguish two types, the rods and the cones.

通常我們會區分為兩大類： 「視桿細胞」與「視錐細胞」。

Now the rods only contribute to a visual impression

視桿細胞在極度昏暗的環境下 才會發揮作用，建立視覺。

under very dim lighting conditions.

And here, in the background, you now see a picture

在背後的投影片上，你會看到

一張主要由視桿細胞帶來的影像——

that might, more or less, be brought about by only the involvement of the rods.

And what you can see is that it's only shades of gray,

你只能看到一些灰階色塊、

it's slightly blurred,

畫面略顯模糊，

and around the point of fixation, which is indicated by the gray dot here,

在這個灰點標示的地方，

you have a little scotoma,

甚至有一個「盲點」， 你完全無法看清楚。

so an area where you can't really see anything.

Now who recognizes what that is?

有人認得這是什麼地方嗎？

Yeah, excellent.

沒錯，很棒！

But it's going to be way easier,

如果我切換到下一張投影片，

and the majority of you will recognize what it is,

你們應該會更容易認出來。 透過視錐細胞的作用，

when I now switch to the next slide,

which is brought about by the involvement of the cones.

你們大多都能認出這個地方。

Of course, it's the town hall of Basel, but now you can appreciate the colors,

這就是巴塞爾市政廳！

現在，你不僅能看到鮮豔的色彩， 還能欣賞到精細的細節。

fine details.

如果這張圖是動態的， 你甚至能捕捉到畫面的細微變化。

And if this was animated, you'd even see fine details in motion.

But this is not the whole story, because only fairly recently,

然而，這還不是事情的全貌。

一直到 2000 年代初期，

only in the early 2000s, another type of cell has been discovered,

科學家才發現了 視網膜中的另一種細胞——

and we call them retinal ganglion cells.

我們稱之為「視網膜神經節細胞」。

Now, you might ask yourselves, "What picture is she going to show next?"

你們可能會想：「接下來 會放什麼圖片呢？」

But I'll have to disappoint you ...

但我要讓大家失望了——

因為我無法放圖片。

I’m not, and I actually can’t, show another picture.

Because from all we know,

根據我們目前所知，

these cells do not contribute to a visual impression.

這些細胞並不負責視覺成像，

But they are exclusively designed

但它們專門設計來

to sense short wavelength proportions in daylight.

偵測日光中較短波長的光，

Sometimes, we also call this blue light.

也就是所謂的「藍光」。

So they're designed to extract important information about the time of day

這些細胞的主要功能，

就是從環境中提取 關於時間的關鍵資訊，

from the environment

and pass this on to the internal biological clock

並將其傳遞給大腦內的生理時鐘。

in the brain.

And I guess you've all experienced how well this biological timing system,

你們應該都體驗過這個生物計時系統，

this connection between our biological clock and the external world, or our eyes,

我們的生理時鐘與外在環境， 即我們的眼睛，兩者密切協作的效果，

works when we, for example, travel across time zones.

例如我們在跨時區旅行時。

Now how much light do we actually need?

那麼，我們到底需要多少光線，

How much light is enough for the positive effects on, for instance,

才能對睡眠產生正面的影響呢？

sleep to occur?

And I have to admit, this is not so easy to answer.

這其實不是一個容易回答的問題。

But I think what we have to keep in keep in mind

但我們必須記住的是，

is that the biological timing system has evolved under the open sky

人類的生理時鐘是 在人類祖先的戶外環境中演化而來的，

and not in offices or museums.

而不是在辦公室或博物館裡。

So it is also optimally tuned to the conditions we find outside.

因此，它是依戶外的自然光而調整的。

Office light or light in rooms

辦公室的燈光或是室內照明，

is in no way comparable to what we find outside.

跟戶外的光線無法相比。

And therefore, from a scientific perspective,

因此，從科學的角度來看，

I can only recommend you to spend as much time as you can

我唯一能給的建議就是： 盡可能多待在戶外，

under the open sky,

but try to make it at least 30 minutes per day.

每天至少 30 分鐘。

Now let's finally talk about sleep.

最後，讓我們來談談睡眠。

And I've repeatedly alluded to the fact that daylight is beneficial

我之前已經多次提到

日光有益睡眠，而且影響很大，

and important for sleep.

And in this context, I'd like to share a little story.

這裡我想分享一個小故事。

So last year, I had to go to hospital for surgery.

去年，我因為手術住院。

And generally, the hospital environment is a very challenging one for sleep.

一般來說，醫院的環境 對睡眠來說是一大挑戰，

Because you spend way too much time in bed, not moving much.

因為大多時間你躺在床上， 幾乎沒有活動，

You might be in pain.

可能還會感到疼痛。

Now and then, someone comes in to check on you, even during the night.

半夜時，護士偶爾會進來查看。

And if you're as lucky as I was, you have a snoring roommate.

如果你像我一樣幸運， 還會有個會打呼的室友。

(Laughter)

（笑聲）

And because you, of course, don't get a lot of daylight.

更糟的是，在醫院裡， 你幾乎無法接觸到自然光。

And that's why many people, while they're in hospital,

這也是為什麼許多住院病人

ask for sleep medication.

會要求吃安眠藥。

But as I consider myself to be a generally good sleeper,

但我自認是個睡眠品質很好的人，

and also because I know how these drugs work,

也知道這類藥物的運作方式，

I didn’t want this.

所以不想依賴它們。

But I knew there was something I could do to help my body sleep as well as possible,

不過，我知道還有別的方法

能幫助我睡得更好—— 即使待在醫院裡。

even in this situation.

And that was to maximize exposure to daylight.

那就是接觸越多日光越好。

Because as a sleep scientist,

身為睡眠科學家，

of course, I know about the research findings.

我當然知道研究結果顯示，

I know that the more daylight that you get,

接觸越多日光，

the more tired you will be in the evening,

到了晚上，你更會覺得疲累，

the easier it will be for you to fall asleep

也就越容易入睡，

and the better the experienced sleep quality.

睡眠品質也會更好。

And in addition,

此外，

daylight exposure has also been shown to increase proportions of deep sleep,

日光曝曬還能增加 「深層睡眠」的比例，

which again has been linked to processes of tissue repair,

而深層睡眠與身體的修復密切相關，

something not to be underestimated after surgery.

對術後恢復至關重要。

And beyond the effects on sleep,

更重要的是，研究也顯示，

we know that patients in brighter rooms experience less pain and less stress.

住在光線充足病房的病人， 疼痛感較低、壓力較少，

And also the effects of daylight on mood are well established.

而日光對於心情的正面影響 也早已被證實。

So I thought it might be time for me to put into practice what I often preach.

所以，這次我決定將理論 化為身體力行。

And I have to confess that usually

我必須承認，

I'm much better at giving advice than following it myself.

我通常比較擅長給別人建議， 自己卻不一定做到。

But here's what I did.

但以下是我做到的事：

So first, when it became free,

第一，當床位有空時，

I asked the nurses to move my bed to the window place,

我請護士幫我換到靠窗的位置，

because that does not only give you power of the fresh air supply,

這樣不僅能享受新鮮空氣，

which is highly recommended in the hospital,

這是住院時絕佳的狀況，

but it also maximizes daylight exposure even though you're inside.

即使在室內，還能接觸到最多的日光。

Second, as soon as I could leave my bed again,

第二，當我恢復到可以下床時，

I went to the park for short walks.

我會到醫院的公園散步， 即使只是短暫的走動。

And last, every meal I had, I tried to take on the little balcony.

第三，每一餐我都盡量 在小陽台上享用。

Did it work?

這樣做有效嗎？

Well, it's a bit difficult to say,

這很難說，

because it of course was a single-case study.

畢竟這只是單一案例。

But from patients suffering from insomnia,

但我們已經知道， 對於失眠症患者來說，

so one of the most common sleep disorders,

最常見的睡眠障礙之一，

光照療法是有效的。

we know that light therapy is beneficial.

And therefore, I would like to encourage all of you,

因此，我想鼓勵在座的每一位——

and perhaps especially those who might belong

特別是那 25% 有睡眠困擾的人——

to the 25 percent suffering from sleep problems,

開始你的「單人實驗」。

to start your own single-case study.

Thank you.

謝謝大家。

(Applause)

（掌聲）