不知道你們是什么情況，雙語君（微信ID：Chinadaily_Mobile）我是很嫉妒那些一沾枕頭就能睡著的人。

不翻來覆去1小時、換上50個睡姿，是絕對不可能入睡的。

不過地鐵公交上，要睡著卻很簡單。乘客的低語混雜著發(fā)動機的嗡鳴像是天然的白噪音，搖晃的車體又類似嬰兒的搖籃，開車不一會兒，車上的人就東倒西歪的了。

在交通工具上更容易入睡，這是真的嗎？

網(wǎng)友PrionBacon評論認為，車上比床上更困倦是因為感覺輸入在一段時間里是穩(wěn)定重復的。

Much like a smartphone, your body will go to sleep when there are no new inputs.

其實就跟智能手機挺像的，身體沒有新的外界輸入的時候就會休眠。

When you are on a bus, your senses will give you the same repetitive inputs. The streets will flow by, the AC and engine adds constant white noise, you're seated and not moving, and the smell... well you hope the smell doesn't change.

坐公交的時候，你感知到的輸入一直是重復的。街道飛馳而過，空調(diào)和引擎發(fā)出的白噪聲，你坐著且并沒有動，還有車上的味道……呃，你希望車上的味道最好不要變。

Any repetitive input going to your brain will eventually be ignored and your brain will start going into a low energy state. The fact that you fall asleep quickly when closing your eyes on a bus is because you were already on the bus for a while and got used to all the repetitive sensory data.

你的大腦最終會忽略這些重復性的輸入，然后進入低耗能模式。你在公交上閉著眼睛就能睡著就是因為你其實坐上公交已經(jīng)好一會兒了，早就習慣了所有重復的感知數(shù)據(jù)。

When you go to bed, you have a lot of new changes. You are lying down, you wear different clothes, you feel the pressure of your covers, you go from bright to dark, noisy to quiet. All of these arenew sensory inputs that your brain needs to get used to before going to sleep.

但是爬上床睡覺的時候，你會經(jīng)歷許多感知變化。你躺倒了，換了睡衣，被子有重量，關(guān)了燈，靜了音。所有這些新的感知輸入都會需要你的大腦花時間來適應(yīng)才能睡著。

科學家們的解釋可能更為嚴謹：交通工具上的瞌睡可能是振動造成的。

發(fā)表在美國職業(yè)安全與健康研究院雜志《工業(yè)健康》（Industrial Health）上的一項研究對交通工具使用者瞌睡受振動的影響進行了調(diào)查。

研究者在實驗中設(shè)置了一個汽車座位，并在座位底下安裝了振動平臺。參與實驗的志愿者們將會經(jīng)受頻率在1-15赫茲之間的正態(tài)分布隨機振動，持續(xù)20分鐘。

研究者發(fā)現(xiàn)，18位志愿者在警覺度測試與瞌睡度評估方面都出現(xiàn)了顯著變化。

這表明，哪怕是只暴露在20分鐘的振動下，志愿者的運動神經(jīng)表現(xiàn)都會受到較強的瞌睡影響。

This is, to our knowledge, the first study to investigate the effects of whole-body vibration on seated human alertness and drowsiness. Our data clearly demonstrate that exposure to vibration has considerable influence on subjective sleepiness levels, and more importantly, human reaction times and lapses of attention.

據(jù)我們所知，這是第一個以全身振動對坐著的人的警覺性和睡意的影響為對象的研究。我們的數(shù)據(jù)清楚地表明，振動對主觀嗜睡水平有很大的影響，更重要的是，對人類的反應(yīng)時間和注意力缺失也有顯著影響。

These findings need to be further consolidated particularly in relation to driving behavior (steering entropy). This line of research can then assist in the development of practical and relevant guidelines for limitation of vibration exposure in the automotive industry, in an effort to reduce the burden of road accidents.

這些研究結(jié)果需要得到進一步的完善，特別是在與駕駛行為（轉(zhuǎn)向熵）相關(guān)的方面（要做進一步調(diào)查）。這類研究將幫助制定實用的相關(guān)指南，指導汽車制造業(yè)限制振動暴露，以達到減少道路事故的目的。

此外，來自RMIT University的研究者們也做了類似的實驗，他們表示：

What might be happening is that the brain becomes synchronized to the vibrations and enters an early stage of sleep –hence, why you might get a whole car full of people nodding off on a long trip.

事實上（在交通工具上）大腦與振動同步并進入了早期的睡眠狀態(tài)——這也就是為什么長途汽車上的乘客總是東倒西歪地“釣魚”了。

That's something for both car manufacturers and road safety experts to think about.

該發(fā)現(xiàn)需要得到汽車制造商與道路安全專家的注意。

很多人覺得是“車上睡得香”導致了“晚上睡不著”。怎樣才能毫不費力地掰正你的生物鐘呢？

Carve out at least 30 minutes of wind-downtime before bed in which you do something relaxing, such as read a book. Dim the lights in the house slightly for an hour or so before bed.

睡前至少留出30分鐘的休息時間，做些放松的事情，比如看書。睡覺前把屋里的燈稍微調(diào)暗一個小時左右。

Disconnect from close-range electronic devices such as laptops, phones, and tablets, as the light from their screens can alert the brain and make it harder to fall asleep.

與筆記本電腦、手機、平板電腦等近距離電子設(shè)備斷連，因為屏幕上的光線會讓大腦清醒，讓你難以入睡。

To calm your mind, do a breathing or relaxation exercise.

為了平心靜氣，你可以做點呼吸放松訓練。

If you get into bed and cannot fall asleep after 20 minutes, get up and return to another space in the house to do a relaxing activity, such as reading or listening to music. Lying in bed awake can create an unhealthy link between your sleeping environment and wakefulness. Instead, you want your bed to conjure sleepy thoughts and feelings only.

如果你臥床20分鐘后還睡不著，那就起來找個別的地方做點放松的活動，比如閱讀或聽音樂。醒著躺在床上會在你的睡眠環(huán)境和清醒狀態(tài)之間建立一個不健康的聯(lián)系。你不想躺著睡不著，你只想讓你的床把你變困。

Wake up at the same time every day. Even if you have a hard time falling asleep and feel tired in the morning, try to get up at the same time (weekends included). This can help adjust your body's clock and aid in falling asleep at night.

每天在同一時間起床。即使你晚上很難入睡，早上又困得不行，也要盡量在同一時間起床（包括周末）。這有助于調(diào)整你的生物鐘，幫助你在夜間入睡。

上述的建議你或許都知道，但是從來都是三天打魚三個月曬網(wǎng)。這時候可以來點外力幫助。

老人家一般都睡得早起得早，如果你有條件，可以搬去和爺爺奶奶住一段時間。你不會忍心在他們睡了之后還四處走動弄出噪音，所以久而久之，你也就可以擁有“養(yǎng)生生物鐘”了。

Notes

sensory /?sens?ri/ adj感覺的；感官的

lapse /l?ps/ n小錯；過失；疏忽；衰弱；衰退

entropy /?entr?pi/ n（物理）熵（系統(tǒng)或過程中不能用來做功的能量的度量）

automotive /???t??mo?t?v/ adj汽車的；機動車的

編輯：陳月華

實習生：馬詠言

來源：Reddit; Industrial Health; Science Alert; Sleep Foundation