????《夢境》（Dreamland）一書探討的是我們無意識的時刻。作者大衛?蘭德爾開篇首先敘述了自己夢游經歷的開始。一天夜晚，作者醒來時發現自己躺在其布魯克林公寓的走廊里，雙手正緊握著一只傷腿。這是他的首次夢游經歷，很明顯（他也記不清楚是怎么回事），他對方向的把控不夠熟練，進而撞到了腿。他去醫院看病，爾后在一個睡眠實驗室呆了一宿，不料卻被醫生告知這次短途之旅的原因還不清楚，無法給他推薦可靠的治療之策。蘭德爾非常驚訝地發現我們對這一領域的認識如此貧瘠，于是展開了調查，這本書就是他調查的成果。

????開篇講述自身夢游經歷是非常自然的事情，但對像我這樣偶爾失眠、以及其他有睡眠問題的人來說，他的不幸遭遇并沒有什么讓人印象深刻的地方。他的腿受了點輕傷？而且只有一次？這算什么大不了的睡眠事故啊！我想這個蘭德爾肯定是個年輕人，書中使用的作者照片似乎證明了這一點【他是路透社（Reuters）的資深記者，《夢境》是他的處女作】“睡眠并不是我們在21世紀頭些年應該擔憂的事情，”他若有所思地寫道。他還說：“在我們大多數人的生活中，睡眠的重要性可能跟使用牙線的重要程度差不多。”

????果真如此嗎？我認識的那些不堪生活重壓的中年人常常受到睡眠不足的困擾，他們大量服用安眠藥，花費數千美元購買花哨的床墊。睡眠不足這個問題幾乎跟子女和房子一樣，讓我們發表了無數單調乏味的長篇大論。對睡眠問題這么高的關注度使得蘭德爾這本書備受矚目——也由此具有非常好的銷售前景。

????在這個奇怪的開篇之后，《夢境：探究陌生的睡眠科學》（Dreamland: Adventures in the Strange Science of Sleep）隨即以詳實的內容對那些個讓人苦惱的8小時進行了引人入勝的探索。我們的問題出在什么地方？大背景是：工業革命和托馬斯?愛迪生發明的那個討厭的電光源搞亂了我們的晝夜節律，以及調節睡眠和許多其他基因功能的激素周期。

????大腦中那個微小的、似乎依然處于爬行類動物階段的松果體也難辭其咎。當它感覺到被延長的黑暗時，它就會產生出誘導睡眠的褪黑激素。然而，蘭德爾解釋稱：“充分的白光，特別是帶著一絲藍色調，宛若藍天的白光能夠誘使松果體誤以為依然艷陽高照。”這意味著，正躺在床上使用個人電腦，觀看電視或用iPad看電影的你（沒錯，就是你），正在摁下作者所說的“反向嗜睡按鈕”。

????這些因素有助于解釋為什么每7個美國人中就有1位有長期的睡眠障礙問題。此外還有一些人有短期的睡眠問題：“每天晚上，大約五分之二的美國成年人都難以入睡或無法持續睡眠，”蘭德爾寫道。他在書中提及一個由此產生的、在私營部門、特別是美軍中迅速興起的領域：“疲勞管理”。由于蘭德爾堆積了太多睡眠不足的士兵和水手犯下致命錯誤的故事，這本書寫到這里時似乎陷入了停頓。他隨后做了一個令人大開眼界的預測：到2020年，所有美軍士兵都將在手腕上帶上睡眠監控器。蘭德爾在書中寫道：“只需點擊幾下鼠標，一位指揮官就可以了解他麾下的每位士兵究竟睡了多長時間，并由此確定他或她可能會作出的決策。”

????作者在最令人震驚的（沒有雙關語意）一章中追溯了安眠藥的歷史，而且差點對大型制藥公司的“嗜睡欺詐”行為進行了指責。僅在美國，這些有力的小藥丸就是一門價值300億美元的生意（2010年數據），比全球人口每年去電影院的花費還稍稍高一些。他指出，在2010年，四分之一美國成年人的藥品柜中放有醫生開的安眠藥。然而，“許多研究顯示，類似安必恩（Ambien）和魯尼斯塔(Lunesta)這樣的安眠藥并沒有顯著改善睡眠質量，對于睡眠數量的改善也僅僅是稍好一點而已，”蘭德爾寫道。

????David K. Randall beginsDreamland, his look at our unconscious hours, by recounting the start of his own Z-journey. The author awakes one night lying in the hallway of his Brooklyn apartment, clutching a wounded leg. He'd sleepwalked for the first time and apparently -- he couldn't remember a thing -- his steering wasn't skillful enough to avoid a leg-on collision. He sees a doctor, then stays overnight in a sleep lab, only to be told that the causes of his jaunt are unclear and no treatments can reliably be recommended. Amazed at how little we know for certain in this realm, Randall investigates, and this book is the result.

????It's a natural place to begin, but to this occasional insomniac and, I suspect, others with sleep problems, his misadventure does not impress. He got a boo-boo on his leg? Once? Big sleeping deal. This Randall must be a younger man, I thought, and his author photo seems to bear that out. (He's a senior reporter for Reuters, and Dreamland is his first book.) "Sleep wasn't something that we were supposed to worry about in the first years of the twenty-first century,'' he muses, adding that "the importance of sleep likely hovers somewhere near that of flossing in most of our lives.''

????Really? The stressed-out middle-agers I know are obsessed with the sleep they're not getting, gobbling Lunesta, and spending thousands on fancy mattresses. Our monologues about (lack of) sleep are almost as tedious as our riffs on children and real estate. This preoccupation is what makes Randall's book such a compelling -- and marketable -- idea.

????After this curious opening gambit, Dreamland, subtitled Adventures in the Strange Science of Sleep, turns out to be an engaging, well-reported exploration of those fraught eight hours. What's our problem? Big picture: the Industrial Revolution and Thomas Edison's pesky electric light screwed up our circadian rhythms, the natural, hormonal cycles that regulate sleep and many other genetic functions.

????The brain's tiny and still-a-bit-too-reptilian pineal gland is also to blame. It produces sleep-inducing melatonin when it senses prolonged darkness. However, Randall explains, "abundant white light -- especially white with a slight blue tint that mimics the sky -- can fool the pineal gland into thinking that the sun is still up.'' That means you over there -- yes, you -- clutching that laptop in bed, or watching the tube, or catching a movie on your iPad -- are pushing what the author calls "reverse snooze buttons.''

????These factors help explain why one out of every seven Americans has a long-term sleep disorder. Then there are the short-termers: "Every night, about two of every five adults in the United States have problems falling asleep and staying asleep,'' Randall writes. He describes the resulting, burgeoning field of "fatigue management,'' in the private sector and especially in the U.S. military. Here the story bogs down a bit as Randall piles on too many examples of sleep-deprived soldiers and sailors making fatal errors. He then makes the eye-opening prediction that by 2020 all U.S. soldiers will wear sleep monitors on their wrists: "With a few clicks of a mouse, a commander will know how many hours each person in the unit has slept -- and, by extension, what kind of decisions he or she will likely make.''

????In the most alarming (no pun intended) chapter, the author traces the history of sleeping pills and comes close to accusing Big Pharma of somnolence fraud. Those potent little pills were a $30 billion business in 2010 in the U.S. alone, or slightly more than the global population spends going to the movies every year. In 2010, he notes, a quarter of U.S. adults had prescription sleeping pills in their medicine cabinets. And yet, Randall writes, "a number of studies have shown that drugs like Ambien and Lunesta offer no significant improvement in the quality of sleep … They give only a tiny bit more in the quantity department, too.''