深度睡眠才是王道

SOMETIME in the dark stretch of the night it happens. Perhaps it’s the chime of an incoming text message. Or your iPhone screen lights up to alert you to a new e-mail. Or you find yourself staring at the ceiling, replaying the day in your head. Next thing you know, you’re out of bed and engaged with the world, once again ignoring the often quoted fact that eight straight hours of sleep is essential.

在漫長的黑夜中，有時會發(fā)生這些事。也許是收到一條文字短信發(fā)出的手機鈴聲。也許是你的iPhone手機屏幕亮起，提醒你收到了一封新的電子郵件。也許是你猛地發(fā)現(xiàn)自己正盯著天花板，白天發(fā)生的一幕幕正在腦中重演。接下來，還沒等你回過神來，你就已經下了床，與這個世界連接在一起，你又一次忘了那句老生常談：連續(xù)八小時的睡眠對人來說必不可少。

Sound familiar? You’re not alone. Thanks in part to technology and its constant pinging and chiming, roughly 41 million people in the United States — nearly a third of all working adults — get six hours or fewer of sleep a night, according to a recent report from the Centers for Disease Control and Prevention. And sleep deprivation is an affliction that crosses economic lines. About 42 percent of workers in the mining industry are sleep-deprived, while about 27 percent of financial or insurance industry workers share the same complaint.

這種事情聽起來很熟悉?并不是只有你一個人會這樣。根據(jù)美國疾病控制與預防中心(Centers for Disease Control and Prevention)最近發(fā)布的報告，在美國，有大約4100萬人——也就是現(xiàn)在成年勞動人口的近三分之一——每天睡眠時間為六小時或更少，這部分跟科技產品和它持續(xù)不斷帶來的鈴聲與震動有關。睡眠不足的問題已經成了各個行業(yè)人群共通的苦惱。在采礦業(yè)有大約42%的工人睡眠不足，而在金融或保險業(yè)里，也有約27%的職工遭受著同樣的折磨。

Typically, mention of our ever increasing sleeplessness is followed by calls for earlier bedtimes and a longer night’s sleep. But this directive may be part of the problem. Rather than helping us to get more rest, the tyranny of the eight-hour block reinforces a narrow conception of sleep and how we should approach it. Some of the time we spend tossing and turning may even result from misconceptions about sleep and our bodily needs: in fact neither our bodies nor our brains are built for the roughly one-third of our lives that we spend in bed.

通常來說，當我們提到自己缺覺的情況越來越嚴重時，人家總會勸我們要早點上床，晚上盡量多睡。但這個解決方法也許恰恰會部分導致失眠的問題發(fā)生。一氣連睡八小時的教條并沒有讓我們得到更好的休息，而僅僅是強化了睡眠以及如何安排合理睡眠的狹隘定義。有時我們躺在床上輾轉反側，也許問題就出在誤解了睡眠和身體的需求上：其實無論是我們的身體還是大腦，都不需要用占生命約三分之一的睡眠時間來維護。

The idea that we should sleep in eight-hour chunks is relatively recent. The world’s population sleeps in various and surprising ways. Millions of Chinese workers continue to put their heads on their desks for a nap of an hour or so after lunch, for example, and daytime napping is common from India to Spain.

人應連睡八小時，這是相對較新的理念。在這個世界上，人們睡覺的方式千姿百態(tài)、令人驚訝。比如在中國，現(xiàn)在仍然有上百萬人每天吃完午飯后，要趴在桌上打一個小時的盹。在從印度到西班牙的國家里，午睡都司空見慣。

One of the first signs that the emphasis on a straight eight-hour sleep had outlived its usefulness arose in the early 1990s, thanks to a history professor at Virginia Tech named A. Roger Ekirch, who spent hours investigating the history of the night and began to notice strange references to sleep. A character in the “Canterbury Tales,” for instance, decides to go back to bed after her “firste sleep.” A doctor in England wrote that the time between the “first sleep” and the “second sleep” was the best time for study and reflection. And one 16th-century French physician concluded that laborers were able to conceive more children because they waited until after their “first sleep” to make love. Professor Ekirch soon learned that he wasn’t the only one who was on to the historical existence of alternate sleep cycles. In a fluke of history, Thomas A. Wehr, a psychiatrist then working at the National Institute of Mental Health in Bethesda, Md., was conducting an experiment in which subjects were deprived of artificial light. Without the illumination and distraction from light bulbs, televisions or computers, the subjects slept through the night, at least at first. But, after a while, Dr. Wehr noticed that subjects began to wake up a little after midnight, lie awake for a couple of hours, and then drift back to sleep again, in the same pattern of segmented sleep that Professor Ekirch saw referenced in historical records and early works of literature.

在20世紀90年代初，第一次有人指出連續(xù)八小時睡眠是個過時的概念，提出這個想法的是弗吉尼亞理工學院(Virginia Tech)的歷史學教授A·羅杰·埃克奇(A. Roger Ekirch)，他花了大量時間翻查關于夜晚的史料，結果發(fā)現(xiàn)古人在談到睡眠時會做出一些奇怪的表述。比方說，在《坎特伯雷故事集》(Canterbury Tales)里，當中的一個人物決定在睡了“第一覺”后回到床上再躺一下。而英國的一位醫(yī)生寫道，在“第一覺”和“第二覺”中間的這段時間，用于學習和思考再合適不過。還有一位16世紀的醫(yī)生認為，做苦力的人之所以能多生幾個孩子，是因為他們要等睡過了“第一覺”后再做愛。埃克奇教授很快發(fā)現(xiàn)，他不是唯一一個發(fā)現(xiàn)交替睡眠周期由來以久的人。當時在馬里蘭州貝塞斯達的美國國家心理健康研究院(National Institute of Mental Health)擔任精神病學專家的托馬斯·A·韋爾(Thomas A. Wehr)進行了一項實驗，參與者不得使用人造光源。由于沒有了電燈、電視或電腦這些產品的照明與干擾，參與試驗的人只能在夜里呼呼大睡——至少一開始是這樣的。但過了一陣子，到了午夜過后，韋爾發(fā)現(xiàn)參與者紛紛醒來，他們在床上醒著躺了幾個鐘頭，然后重新睡去，這樣斷斷續(xù)續(xù)的睡眠周期，與?？似娼淌趶氖妨虾驮缙谖墨I中發(fā)現(xiàn)的例證是一樣的。

It seemed that, given a chance to be free of modern life, the body would naturally settle into a split sleep schedule. Subjects grew to like experiencing nighttime in a new way. Once they broke their conception of what form sleep should come in, they looked forward to the time in the middle of the night as a chance for deep thinking of all kinds, whether in the form of self-reflection, getting a jump on the next day or amorous activity. Most of us, however, do not treat middle-of-the-night awakenings as a sign of a normal, functioning brain.

看起來，如果得到一個遠離現(xiàn)代生活的機會，我們的身體能夠自然而然地適應片斷式的睡眠節(jié)奏。參加實驗的人漸漸喜歡上了用一種新的方式來感受夜晚。一旦他們打破了關于睡眠形式的既有觀念，就會期待著能趁著午夜時分來進行沉思，不管他們是用這段時間來進行反思、為第二天做好準備、還是想感情方面的事情。不過，我們中的大部分人都覺得在子夜時分醒來，不能算是大腦運行如常的信號。

Doctors who peddle sleep aid products and call for more sleep may unintentionally reinforce the idea that there is something wrong or off-kilter about interrupted sleep cycles. Sleep anxiety is a common result: we know we should be getting a good night’s rest but imagine we are doing something wrong if we awaken in the middle of the night. Related worries turn many of us into insomniacs and incite many to reach for sleeping pills or sleep aids, which reinforces a cycle that the Harvard psychologist Daniel M. Wegner has called “the ironic processes of mental control.”

那些兜售安眠藥、呼吁人們要多休息的醫(yī)生，或許在不經意間強調了這種想法，那就是斷斷續(xù)續(xù)的睡眠周期有問題，或者不健康。這往往會導致人們在睡眠問題上產生焦慮：我們知道自己應當在晚上好好睡一覺，但又擔心如果我們在半夜醒來，一定是出了什么問題。正是因為這種種顧慮令許多人真的患上了失眠癥，不得不求助于安眠藥或助眠藥物，如此一來就形成了一個惡性循環(huán)，用哈佛大學心理學家丹尼爾·M·韋格納(Daniel M. Wegner)的話來說，這是“精神控制的諷刺的過程。”

As we lie in our beds thinking about the sleep we’re not getting, we diminish the chances of enjoying a peaceful night’s rest.

當我們躺在床上，想著自己無法企及的睡眠時，我們已經斷送了在這個寧靜的夜晚盡情休息的機會。

This, despite the fact that a number of recent studies suggest that any deep sleep — whether in an eight-hour block or a 30-minute nap — primes our brains to function at a higher level, letting us come up with better ideas, find solutions to puzzles more quickly, identify patterns faster and recall information more accurately. In a NASA-financed study, for example, a team of researchers led by David F. Dinges, a professor at the University of Pennsylvania, found that letting subjects nap for as little as 24 minutes improved their cognitive performance.

而事實上，近來有不少研究都表明，任何深度睡眠——不論是連睡八小時，還是打半小時的盹——都能讓我們的大腦以更高水平運轉，讓我們想出更好的主意，更迅速地解答謎題，更快認出圖案，更準確地回想起各種信息。舉例來說，美國航空航天局(NASA)出資進行了一項研究，賓夕法尼亞大學(University of Pennsylvania)的大衛(wèi)·F·丁格斯(David F. Dinges)教授帶領一隊研究者進行實驗，結果發(fā)現(xiàn)讓被試者小睡24分鐘，就可以提高他們的認知表現(xiàn)。

In another study conducted by Simon Durrant, a professor at the University of Lincoln, in England, the amount of time a subject spent in deep sleep during a nap predicted his or her later performance at recalling a short burst of melodic tones. And researchers at the City University of New York found that short naps helped subjects identify more literal and figurative connections between objects than those who simply stayed awake.

而在另一項由英國林肯大學(University of Lincoln)的西蒙·杜蘭特(Simon Durrant)教授所領導的研究發(fā)現(xiàn)，受試者在小睡中深度睡眠的時間長度，將可以預示他們在之后回憶一小段旋律的能力。紐約城市大學(City University of New York)的研究者也發(fā)現(xiàn)，小睡片刻的受試者比起一直清醒著的人，能夠更準確地辨認物體間表面上和象征意義上的聯(lián)系。

Robert Stickgold, a professor of psychiatry at Harvard Medical School, proposes that sleep — including short naps that include deep sleep — offers our brains the chance to decide what new information to keep and what to toss. That could be one reason our dreams are laden with strange plots and characters, a result of the brain’s trying to find connections between what it’s recently learned and what is stored in our long-term memory. Rapid eye movement sleep — so named because researchers who discovered this sleep stage were astonished to see the fluttering eyelids of sleeping subjects — is the only phase of sleep during which the brain is as active as it is when we are fully conscious, and seems to offer our brains the best chance to come up with new ideas and hone recently acquired skills. When we awaken, our minds are often better able to make connections that were hidden in the jumble of information.

哈佛大學醫(yī)學院的精神病學教授羅伯特·斯蒂克戈爾德(Robert Stickgold)認為，睡眠——包括產生了深度睡眠的小睡——會讓我們的大腦得到一個機會去決定新的信息孰去孰留。正因為此，我們的夢才充斥著奇怪的情節(jié)與人物，這是因為我們的大腦此時正在試圖尋找最近學到的新東西與存儲在長期記憶中的知識之間存在的關聯(lián)。快速眼動睡眠——之所以叫這個名字，是因為發(fā)現(xiàn)了這個睡眠階段的研究者很驚異地看到睡覺的人眼皮在急速顫動——是整個睡眠中唯一一個大腦跟完全清醒時同樣保持活動的階段，而且這種睡眠階段看來能為大腦提供一個孕育新想法，磨煉近期學會的技能的良機。等到醒來時，我們往往更有能力在錯綜復雜的信息中發(fā)現(xiàn)隱秘的聯(lián)系。

Gradual acceptance of the notion that sequential sleep hours are not essential for high-level job performance has led to increased workplace tolerance for napping and other alternate daily schedules.

連睡幾個小時并不是高水平工作表現(xiàn)的必要條件，在漸漸接受了這個概念后，企業(yè)也越來越能包容員工在工作場所打盹，或采取其他類似的間斷工作節(jié)奏。

Employees at Google, for instance, are offered the chance to nap at work because the company believes it may increase productivity. Thomas Balkin, the head of the department of behavioral biology at the Walter Reed Army Institute of Research, imagines a near future in which military commanders can know how much total sleep an individual soldier has had over a 24-hour time frame thanks to wristwatch-size sleep monitors. After consulting computer models that predict how decision-making abilities decline with fatigue, a soldier could then be ordered to take a nap to prepare for an approaching mission. The cognitive benefit of a nap could last anywhere from one to three hours, depending on what stage of sleep a person reaches before awakening.

比方說，谷歌的員工現(xiàn)在就可以在工間小睡，因為這家公司相信這可能會提高員工的生產力。沃爾特·里德陸軍研究院(Walter Reed Army Institute of Research)的行為生物學系主任托馬斯·巴爾金(Thomas Balkin)設想，在不遠的將來，軍事指揮官可以通過手表大小的睡眠監(jiān)控儀，掌握每個士兵在過去24小時里睡眠的總時長。在對比電腦模型，預知士兵的個人決策力是否已經因為疲勞而有明顯下降后，指揮官可以下令士兵就地小睡，好為即將到來的任務養(yǎng)精蓄銳。睡一小覺，認知能力能因此在一到三小時內得到提升，具體時間長度取決于這個人在醒來之前處在什么樣的睡眠階段。

Most of us are not fortunate enough to work in office environments that permit, much less smile upon, on-the-job napping. But there are increasing suggestions that greater tolerance for altered sleep schedules might be in our collective interest. Researchers have observed, for example, that long-haul pilots who sleep during flights perform better when maneuvering aircraft through the critical stages of descent and landing.

大部分人不會有這么好的運氣，能在允許甚至鼓勵上班時打瞌睡的地方工作。不過有越來越多人開始相信，允許間斷睡眠對大家都有益。舉例來說，研究者發(fā)現(xiàn)飛長途航班的飛行員如果能在途中睡一覺，在駕駛飛機起降的關鍵時刻可以表現(xiàn)得更出色。

Several Major League Baseball teams have adapted to the demands of a long season by changing their sleep patterns. Fernando Montes, the former strength and conditioning coach for the Texas Rangers, counseled his players to fall asleep with the curtains in their hotel rooms open so that they would naturally wake up at sunrise no matter what time zone they were in — even if it meant cutting into an eight-hour sleeping block. Once they arrived at the ballpark, Montes would set up a quiet area where they could sleep before the game. Players said that, thanks to this schedule, they felt great both physically and mentally over the long haul.

有幾支棒球大聯(lián)盟的球隊已經開始改變隊員的睡眠節(jié)奏，來適應一個漫長賽季的需求。德州游騎兵(Texas Rangers)的前任力量和體能教育費爾南多·蒙特斯(Fernando Montes)建議球員們在酒店睡覺時，把窗簾拉開，這樣他們不管身處哪個時區(qū)都能伴著日出自然醒來——哪怕這意味著八小時的連續(xù)睡眠被打破。在球員來到場上時，蒙特斯會騰出一塊安靜的角落，讓球員們在賽前小憩一下。球員們說，幸好有了這種睡眠節(jié)奏，他們在整整一個賽季，覺得自己的體能和精力都非常充沛。

Strategic napping in the Rangers style could benefit us all. No one argues that sleep is not essential. But freeing ourselves from needlessly rigid and quite possibly outdated ideas about what constitutes a good night’s sleep might help put many of us to rest, in a healthy and productive, if not eight-hour long, block.

游騎兵隊戰(zhàn)略性的小睡方式，也許對我們大家都有用。沒人說睡眠這件事并不重要。但如果我們能從嚴苛得毫無必要、而且很有可能是完全落伍的睡眠觀念中解放出來，或許有很多人就此可以睡得更健康、更有效率，哪怕他們不是連睡八個小時。