你微笑世界也会微笑：快乐会传染

西西

Ever wonder whether happy people have something you don't, something that keeps them cheerful, chipper and able to see the good in everything? It turns out they do — they have happy friends.
Harvard and the University of California at San Diego, who report in the British Medical Journal online that happiness spreads among people like a salubrious disease. Dr. Nicholas Christakis and James Fowler studied nearly 5,000 people and their more than 50,000 social ties to family, friends and co-workers, and found that an individual's happiness is chiefly a collective affair, depending in large part on his or her friends' happiness — and the happiness of their friends' friends, and even the friends of their friends' friends. The merriment of one person, the researchers found, can ripple out and cause happiness in people up to three degrees away. So if you're happy, you increase the chance of joy in your close friend by 25%; a friend of that friend enjoys a 10% increased chance. And that friend's friend has a 5.6% higher chance. (See the Year in Health, from A to Z.)
"This is a very serious piece of research. It's pioneering," says Dr. Richard Suzman, director of the division of behavioral and social research at the National Institute on Aging. "We are barely beginning to understand its translational and applied aspects."
The authors analyzed data from the Framingham Heart Study, a historic study of heart disease among nearly 5,000 people begun in 1948. Because it was designed to follow participants and their offspring over several generations, the study's creators recorded detailed information about each person's closest relatives and friends, to better keep tabs on the original participants. That database served as an ideal social laboratory for Christakis and Fowler, who questioned each participant and his or her friends and family about their emotional state three times over 20 years.
The idea of mood transfer is not exactly revolutionary. It makes sense, after all, that your happiness will affect your closest friends, and that their emotional state will influence your own. (Interestingly, the same association was not found with unhappiness, despite the old adage about misery and company, and the contagion effect was weaker among family members than friends, possibly because while people take a cue from friends, they take for granted their families and spouses.) What was less expected was that the effect was sustained up to three degrees of separation away, among people who may not necessarily know one another. You may owe your good cheer to your friend's brother's girlfriend, even if you don't know her name.
That's the power of the social network, which, the authors argue, may impact our emotional state even more than our individual choices and environments. And it is not merely a result of like seeking like. The authors compared their observed network with a control network in which they randomly assigned feelings of happiness to individuals, and were able to rule out the possibility that happy people were simply clustering together by choice. Indeed, in another study in the same issue of the BMJ, researchers from Yale University and the Federal Reserve of Boston showed a similar tendency to cluster among people who, for example, are the same height, or suffer from acne, or headaches. But once the researchers adjusted for confounding factors, the network dissolved; in Christakis and Fowler's paper, the happiness link remained unbroken.
But the effect was limited by space and time. Researchers found that the risk of catching happiness increased with proximity: so a next-door neighbor enjoys a 34% increased chance of happiness by living near a happy person, but a friend who lives across town is less affected. And the best-connected social networkers — those who were at the center of their social nodes — were more likely to become happy than people on the fringes. Viral happiness was relatively short lived, however, lasting about a year.
This is the authors' third such networking study suggesting that the social group is a powerful super-organism that wields much influence over individuals' well-being. Previous analyses by Christakis and Fowler, based on the same pool of data, have shown that obesity is similarly contagious, as is the act of quitting smoking.
The researchers' hope is that a better understanding of how people pick up and pass on behaviors will help health officials create more targeted public-health messages. Antismoking campaigns aimed at teens, for example, might be more powerful if they were geared toward the most socially connected students in a high school — rather than individual smokers. "We are always looking for areas to invest in, promising new areas of research that will give us new levels of ability to help people, and without a doubt I see this as a very promising area," says Suzman.


你有没有想过为什么有些人一直很快乐，总能看到好的一面，他们是不是有些你没有的东西呢？是的。他们有快乐的朋友。
这是哈佛大学和圣地亚哥的加州大学研究员的研究结果。他们认为，快乐会如有益病毒在人们之间传染开。该研究结果已经发表到《英国医学杂志》网络版。尼可拉. 克里斯塔基斯博士和詹姆斯.福勒博士研究了近5000人及其亲属、朋友和同事50000多人，发现个人的快乐主要来自于集体，很大程度上取决于他或者她的朋友是否快乐——或者他们的朋友的朋友、甚至是朋友的朋友的朋友是否快乐。研究员发现，一个人的快乐会像水波一样荡开来，影响到三层朋友。因此，如果你很开心，你可以增加你的密友25%的快乐几率；而你朋友的朋友可以增加10%的快乐几率；你朋友的朋友的朋友则可以增加5.6%的快乐几率。
“这是一项很严肃的研究，很有开创性。”理查德博士说。他是国家老年研究中心行为和社会研究分部的主任。“我们对其所隐含的意义及其应用性的了解才刚刚开始。”
该报告的作者们分析的是来自拂明盛心脏研究数据。拂明盛心脏研究开始于1948年，在近5000人种展开，有重大历史意义。因为该研究需要跟踪参与者及其几代后人，为了更好的跟踪研究参与者，该研究的创立者对每个参与者的密友及近亲属的信息进行了详细记录。这些记录对克莱斯塔基斯和福勒来说是完美的社会实验室，在过去的20年中，他们共三次询问了参与者及其家属和朋友的情绪状态。
情绪转移这种提法并不完全具有革命性。不管怎样，你的快乐会影响到密友，而他们的情绪也会影响到你，这是很有道理的。（有趣的是，尽管有各种关于苦恼和同伴的格言，不快乐并没有同等的关联性，它在家人之间的传染性要小于在朋友之间的，这也许是因为人们容易受朋友的影响，而家人和配偶不快乐时，他们认为是理所当然的。）更意想不到的是，快乐影响到三层关系，或许你影响到了别人，却不认识他们。你可能会因为你朋友的兄弟的女朋友的快乐而快乐，尽管你连她的名字都不知道。
这就是社会关系的影响力，该研究的作者认为，社会关系对情绪的影响要大于来自个人抉择和环境的影响。这不仅仅归因于物以类聚。作者将他们的观察组和控制组进行的对比。他们要求后者表现出快乐的情绪，如此一来，就可以排除快乐的人总是选择性的聚集到一起这种可能性。事实上，来自耶鲁大学和波士顿美联储的研究者在《英国医学杂志》发表的另外一篇同一主题的文章指出，同等身高、患痤疮或者头痛的人都有可能聚集到一起。但是，一旦研究者把这种分类打乱，这种社会网络就散去了；而在克里斯塔基斯和福勒的研究中，快乐联系仍然保持着。
但是，快乐的影响力受时间和空间的限制。研究者发现受快乐传染的风险随着亲进性的增加而增加：一个快乐者的邻居的快乐程度会增加34%，而住在镇的另一边的快乐者朋友受到的影响就小多了。社会网络中最紧要的一环——那些处于他们的社会网络的中心的人——会比处于该网络边缘的人快乐。病毒性快乐生存时间相对较短，但是却能持续约一年。
这是这些作者第三篇关于社会群体是影响个人健康的重要因素的研究。克里斯塔基斯和福勒先前基于同样的数据所作的研究表明，肥胖症和戒烟有着同样的传染性。
研究者希望人们可以更清楚的了解自身的行为可以帮助卫生政府官员传递有针对性的改善公共卫生的讯息。比如，针对青少年的禁烟运动若在高中学校里社交最广泛的学生之间展开——而不是针对单个的学生，将会更有成效。“我们现在正在寻找投资领域，新的有前景的领域可以让我们更好的帮助别人，毫无疑问，我认为这就是一个很有前景的领域。”Suzman说。