你以為你上網(wǎng)的時候只是憑借你自己的愛好么?其實你已經(jīng)被變相注射了一種激素，這個東西撐起了市值千億的互聯(lián)網(wǎng)帝國，但是也可能摧毀你的正常生活。

In an unprecedented attack of candour, Sean Parker, the 38-year-old founding president of Facebook, recently admitted that the social network was founded not to unite us, but to distract us. “The thought process was: ‘How do we consume as much of your time and conscious attention as possible?’” he said at an event in Philadelphia in November. To achieve this goal, Facebook’s architects exploited a “vulnerability in human psychology”, explained Parker, who resigned from the company in 2005. Whenever someone likes or comments on a post or photograph, he said, “we… give you a little dopamine hit”. Facebook is an empire of empires, then, built upon a molecule.

最近，F(xiàn)acebook前高管，38歲的肖恩.帕克(SeanParker)終于承認，社交網(wǎng)絡的建立不是為了讓我們更加親密無間，而是為了分散我們的注意力。去年11月，他在費城的一次活動上表示，這一思路其實是：“我們?nèi)绾伪M可能多地占用你的時間和注意力?”2005年從Facebook辭職的帕克解釋道，為了達到這一目的，F(xiàn)acebook的架構師利用了“人類心理的弱點”。每當你給一篇文章或照片點贊或留言時，帕克說，“這就是我們給你做的輕度多巴胺‘注射’”。Facebook這家“王中之王”的互聯(lián)網(wǎng)巨頭，就建立在這樣一個小小分子之上。

Dopamine, discovered in 1957, is one of 20 or so major neurotransmitters, a fleet of chemicals that, like bicycle couriers weaving through traffic, carry urgent messages between neurons, nerves and other cells in the body. These neurotransmitters ensure our hearts keep beating, our lungs keep breathing and, in dopamine’s case, that we know to get a glass of water when we feel thirsty, or attempt to procreate so that our genes may survive our death.

多巴胺在1957年被發(fā)現(xiàn)，是20多種主要的神經(jīng)遞質之一。這群化學物質，就像騎著自行車的郵遞員穿梭于車流中，在神經(jīng)元、神經(jīng)纖維和身體其他細胞之間傳遞緊急信息。這些神經(jīng)遞質確保我們的心臟繼續(xù)跳動，肺保持呼吸。拿多巴胺來說，它能在我們感到口渴的時候提醒我們喝水，也能在需要把基因傳遞給后代的時候讓我們產(chǎn)生繁殖的沖動。

In the 1950s, dopamine was thought to be largely associated with physical movement after a study showed that Parkinsonism (a group of neurological disorders whose symptoms include tremors, slow movement and stiffness) was caused by dopamine deficiency. In the 1980s, that assumption changed following a series of experiments on rats by Wolfram Schultz, now a professor of neuroscience at Cambridge University, which showed that, inside the midbrain, dopamine relates to the reward we receive for an action. Dopamine, it seemed, was to do with desire, ambition, addiction and sex drive.

20世紀50年代，一項研究表明帕金森綜合癥(一組神經(jīng)病學癥狀包括震顫、運動緩慢和僵硬)是由多巴胺缺乏引起的，從此人們認為多巴胺主要與身體運動功能有關。到了20世紀80年代，這一假設受到了挑戰(zhàn)，當時，劍橋大學的神經(jīng)科學教授沃爾夫勒姆.舒爾茨(WolframSchultz)對大鼠進行了一系列實驗，結果表明，在中腦內(nèi)，多巴胺與獎賞行為有關。這種分子與欲望、野心、毒癮和性沖動的信號通路似乎都有關系。

Schultz and his fellow researchers placed pieces of apple behind a screen and immediately saw a major dopamine response when the rat bit into the food. This dopamine process, which is common in all insects and mammals, is, Schultz tells me, at the basis of learning: it anticipates a reward to an action and, if the reward is met, enables the behaviour to become a habit, or, if there’s a discrepancy, to be adapted. (That dishwasher tablet might look like a delicious sweet, but the first fizzing bite will also be the last.) Whether dopamine produces a pleasurable sensation is unclear, says Schultz. But this has not dented its reputation as the miracle bestower of happiness.

舒爾茨和他的同事們先將蘋果片——對于大鼠來說這是不折不扣的美食——藏在了隱蔽的位置，當大鼠找到并咬下這些食物時，他們立刻觀察到了動物腦內(nèi)的多巴胺反應。這種多巴胺的釋放在所有昆蟲和哺乳動物中都是常見的。舒爾茨告訴我，作為學習的基礎，多巴胺參與了對一個行為的獎勵，如果得到了獎勵，就能使行為成為一種習慣;如果沒有得到獎勵，行為就會做出相應調整。比如你把洗碗海綿看成美味的蛋糕，上去咬了一口，發(fā)現(xiàn)這不是蛋糕，下次就不會再咬上去了。舒爾茨說，多巴胺能否直接產(chǎn)生愉悅的感覺目前還不清楚。但這并沒有妨礙它成為帶來幸福感的“神藥”。

Dopamine inspires us to take actions to meet our needs and desires – anything from turning up the heating to satisfying a craving to spin a roulette wheel – by anticipating how we will feel after they’re met. Pinterest, the online scrapbook where users upload inspirational pictures, contains endless galleries of dopamine tattoos (the chemical symbol contains two outstretched arms of hydroxide, and a three-segmented tail), while Amazon’s virtual shelves sag under the weight of diet books intended to increase dopamine levels and improve mental health.

從打開暖氣按鈕這樣的小事，到滿足輪盤賭的欲望，多巴胺激勵我們采取行動來滿足我們的需求和欲望。在線圖片剪貼簿Pinterest是一款可以讓用戶上傳加工圖片和照片的社交軟件，其中包含大量展示多巴胺化學式紋身的照片(該化學符號包含兩臂的氫氧根和三段分割的尾巴)。亞馬遜的虛擬書架則擠滿了減肥食譜，就為了增加多巴胺水平，改善心理健康。

“We found a signal in the brain that explains our most profound behaviours, in which every one of us is engaged constantly,” says Shultz. “I can see why the public has become interested.”

舒爾茨說:“我們在大腦中發(fā)現(xiàn)了一個信號，可以解釋我們意義最為深遠的行為，我們每個人都沉浸其中，停不下來——我可以理解為什么公眾會對此感興趣了。”

In this way, unlike its obscure co-workers norepinephrine and asparagine, dopamine has become a celebrity molecule. The British clinical psychologist Vaughan Bell once described dopamine as “the Kim Kardashian of molecules”. In the tabloid press, dopamine has become the transmitter for hyperbole. “Are cupcakes as addictive as cocaine?” ran one headline in the Sun, citing a study that showed dopamine was released in the orbital frontal cortex – “the same section activated when cocaine addicts are shown a bag of the class A drug” – when participants were shown pictures of their favourite foods. Still, nowhere is dopamine more routinely name-dropped than in Silicon Valley, where it is hailed as the secret sauce that makes an app, game or social platform “sticky” – the investor term for “potentially profitable”.

與默默無聞的“同事”去甲腎上腺素和天冬酰胺不同，多巴胺從此成為了“名流分子”。英國臨床心理學家沃恩.貝爾(VaughanBell)曾將多巴胺描述為“分子中的金.卡戴珊”�！短�陽報》(theSun)刊登了一篇題為“紙杯蛋糕會像可卡因一樣讓人上癮嗎?”的文章，其中引用了一項研究，該研究顯示，向被試展示他們最喜歡的食物圖片時，大腦的前額葉皮層釋放了多巴胺——“當向可卡因成癮者展示一袋毒品時，同樣的區(qū)域也會被激活”。盡管如此，在硅谷，多巴胺比在其他任何地方都更常見，它被譽為“神秘醬汁”，讓應用程序、游戲或社交平臺“更有粘性”，這被投資者稱為“潛在利潤”。

“Even a year or two before the scene about persuasive tech grew up, dopamine was a molecule that had a certain edge and sexiness to it in the cultural zeitgeist,” explains Ramsay Brown, the 28-year-old cofounder of Dopamine Labs, a controversial California startup that promises to significantly increase the rate at which people use any running, diet or game app. “It is the sex, drugs and rock’n’roll molecule. While there are many important and fascinating questions that sit at the base of this molecule, when you say ‘dopamine’, people’s ears prick up in a way they don’t when you say ‘encephalin’ or ‘glutamate’. It’s the known fun transmitter.”

“在誘導技術成熟以前，多巴胺就是一種極具優(yōu)勢并帶有性文化思潮的分子，”拉姆齊.布朗(RamsayBrown)解釋道。這位28歲的年輕人創(chuàng)辦了“多巴胺實驗室”(DopamineLabs)，這是一家飽受爭議的加州企業(yè)，致力于大幅增加人們使用的跑步、飲食或游戲的軟件的頻率。“這個分子代表了性、毒品和搖滾樂。當你提到多巴胺時，人們的耳朵就會豎起來，因為在這個分子的背后有許多重要而迷人的問題，但當你說腦啡肽或谷氨酸時就不會。多巴胺是個廣為人知的樂趣傳遞者。”

Fun, perhaps, but as with Kardashian, dopamine’s press is not entirely favourable. In a 2017 article titled “How evil is tech?”, the New York Times columnist David Brooks wrote: “Tech companies understand what causes dopamine surges in the brain and they lace their products with ‘hijacking techniques’ that lure us in and create ‘compulsion loops’.” Most social media sites create irregularly timed rewards, Brooks wrote, a technique long employed by the makers of slot machines, based on the work of the American psychologist BF Skinner, who found that the strongest way to reinforce a learned behaviour in rats is to reward it on a random schedule. “When a gambler feels favoured by luck, dopamine is released,” says Natasha Schüll, a professor at New York University and author of Addiction By Design: Machine Gambling in Las Vegas. This is the secret to Facebook’s era-defining success: we compulsively check the site because we never know when the delicious ting of social affirmation may sound.

除了樂趣，多巴胺也引來了不少批評的聲音。在2017年《紐約時報》的專欄作家大衛(wèi).布魯克斯(DavidBrooks)寫的一篇名為《科技有多邪惡?》的文章中說道：“科技公司明白是什么原因導致大腦中的多巴胺激增，他們在自己的產(chǎn)品上使用‘劫持技術’，誘騙我們?nèi)刖植��?chuàng)造‘強制循環(huán)’。”布魯克斯寫道，大多數(shù)社交網(wǎng)絡平臺都會創(chuàng)建一些不規(guī)則發(fā)放的獎勵，這是老虎機制造商慣用的伎倆。這項技術的應用是基于美國心理學家BF.斯金納(BFSkinner)的研究成果，他發(fā)現(xiàn)強化大鼠的習得行為的最佳方式是隨機安排獎勵。紐約大學(NewYorkUniversity)教授、《被設計的成癮:在拉斯維加斯賭博》(AddictionbyDesign:MachineGamblinginLasVegas)一書的作者娜塔莎.舒爾(NatashaSchull)說：“當一個賭徒覺得運氣來了時，多巴胺就會釋放出來。”這就是Facebook成功的秘訣：我們像得了強迫癥一樣頻繁刷新這個網(wǎng)站，就是因為我們永遠不知道什么時候會收到來自他人的美妙贊同。