Anjan Chatterjee从进化心理学和认知神经科学的角度研究了一个自然的最迷人的概念：美。为什么某些线、颜色和形状的的构造组合，会带给我们一种美的感受?他将深入我们的大脑，探寻这背后的科学原因。下面是小编为大家收集关于TED英语演讲：你如何判断什么是美，欢迎借鉴参考。

　　演说题目：How your brain decides what is beautiful

　　演说者：Anjan Chatterjee

　　It's 1878. Sir Francis Galton gives aremarkable talk. He's speaking to the anthropologic institute of Great Britainand Ireland. Known for his pioneering work in human intelligence, Galton is abrilliant polymath. He's an explorer, an anthropologist, a sociologist, apsychologist and a statistician. He's also a eugenist.

　　1878 年，弗朗西斯高尔顿爵士 做了一场非凡的演说。演说的对象是英国 与爱尔兰的人类学机构。高尔顿以他在人类智慧领域的先驱工作闻名，他是个博学的人。他是个探险家、是个人类学家、是个社会学家、是个心理学家、也是个统计学家。他还是个优生学家。

　　In this talk, hepresents a new technique by which he can combine photographs and producecomposite portraits. This technique could be used to characterize differenttypes of people. Galton thinks that if he combines photographs of violentcriminals, he will discover the face of criminality. But to his surprise, thecomposite portrait that he produces is beautiful.

　　在那场演说中，他展示了一项新技术，他可以把照片结合产生出复合的肖像。这项技术可以用来 描绘不同类型人的特色。高尔顿认为，如果他可以把 暴力罪犯的照片结合起来，他也许就能够发现罪犯的面貌。但，出乎他意料，他制作出的复合肖像竟然很美。

　　Galton's surprising finding raises deep questions:What is beauty? Why do certain configurations of line and color and form exciteus so? For most of human history, these questions have been approached usinglogic and speculation. But in the last few decades, scientists have addressedthe question of beauty using ideas from evolutionary psychology and tools ofneuroscience. We're beginning to glimpse the why and the how of beauty, atleast in terms of what it means for the human face and form. And in theprocess, we're stumbling upon some surprises.

　　高尔顿的意外发现，带出了更深的问题： 美，到底是什么? 为什么将线条、颜色、形式 做某些配置之后就能感动我们? 在大部份的人类史上，人们都用逻辑和推测来处理这些问题。但在最近几十年，科学家在处理关于美的问题时，用的是来自演化心理学的想法 以及神经科学的工具。我们开始研究美的定义与成因，至少对脸部及外型 已经开始有了审美的概念。在过程中，我们偶然发现了一些惊喜。

　　When it comes to seeing beauty in eachother, while this decision is certainly subjective for the individual, it'ssculpted by factors that contribute to the survival of the group. Manyexperiments have shown that a few basic parameters contribute to what makes aface attractive. These include averaging, symmetry and the effects of hormones.Let's take each one of these in turn.

　　谈到互看顺眼时，对个人而言，其审美标准 绝对是主观的，原因是因为这样对 团体的生存有所贡献。许多实验都显示，有几个基本参数与脸孔的吸引力有关。这些参数包括大众脸、对称性、以及荷尔蒙的影响。我们一项一项来讨论。

　　Galton's finding that composite or averagefaces are typically more attractive than each individual face that contributes tothe average has been replicated many times. This laboratory finding fits withmany people's intuitions. Average faces represent the central tendencies of agroup. People with mixed features represent different populations, andpresumably harbor greater genetic diversity and adaptability to theenvironment. Many people find mixed-race individuals attractive and inbredfamilies less so.

　　高尔顿发现，混血儿或有大众脸的人 通常比一般单一血种的后代 更具吸引力。这个实验室的发现，与许多人的直觉不谋而合。一般人的面孔代表了一个团体的主要倾向。有混血特征的人，代表着不同的族群，也被认定有着更高的 基因多样性、以及对环境的适应力。许多人觉得混血儿的脸孔 是较有吸引力的，而近亲交配的家庭就比较没吸引力。

　　The second factor that contributes tobeauty is symmetry. People generally find symmetric faces more attractive thanasymmetric ones. Developmental abnormalities are often associated withasymmetries. And in plants, animals and humans, asymmetries often arise fromparasitic infections. Symmetry, it turns out, is also an indicator of health.

　　与美有关的第二个因子是对称性。一般来说，人们觉得对称的面孔 比不对称的更有吸引力。不正常的成长通常都与不对称有关。植物、动物、及人类，造成不对称的原因通常是受到寄生虫的感染。因此，对称性 也是健康的指标。

　　In the 1930s, a man named Maksymilian Faktorowicz recognized the importance ofsymmetry for beauty when he designed the beauty micrometer. With this device,he could measure minor asymmetric flaws which he could then make up for withproducts he sold from his company, named brilliantly after himself, Max Factor,which, as you know, is one of the world's most famous brands for "makeup."

　　在 1930 年代，有个叫蜜斯米兰佛陀维兹的人，当时他在设计美容校准仪时，体认到对称性对于美的重要性，有了这个仪器，他可以测量出微小的对称瑕疵，接着他就可以用他公司所贩卖的产品来补救，并很聪明地把他的名字取其谐音 作为公司的名称，蜜丝佛陀，各位应该知道，它是世界知名的 化妆品公司之一。

　　The third factor that contributes to facialattractiveness is the effect of hormones. And here, I need to apologize forconfining my comments to heterosexual norms. But estrogen and testosterone playimportant roles in shaping features that we find attractive. Estrogen producesfeatures that signal fertility.

　　与脸部吸引力有关的第三个因子是 荷尔蒙的影响力。在此我得道个歉，因为我的意见 仅限于异性恋的标准上。但在形成被我们认为有吸引力的那些特征上，雌激素和睪丸素扮演了重要的角色。雌激素产生的特征会传达出生育力。

　　Men typically find women attractive who haveelements of both youth and maturity. A face that's too baby-like might meanthat the girl is not yet fertile, so men find women attractive who have largeeyes, full lips and narrow chins as indicators of youth, and high cheekbones asan indicator of maturity.

　　男人通常会觉得，同时俱有 年轻和成熟元素的女人 很有吸引力。太幼齿的面孔可能代表着 这个女孩还没有生育能力，所以能吸引男人的女人通常有大眼睛、丰唇、窄下巴，这些都是年轻的指标; 而高颧骨则是成熟的指标。

　　Testosterone produces features that weregard as typically masculine. These include heavier brows, thinner cheeks andbigger, squared-off jaws. But here's a fascinating irony. In many species, ifanything, testosterone suppresses the immune system. So the idea thattestosterone-infused features are a fitness indicator doesn't really make awhole lot of sense. Here, the logic is turned on its head. Instead of a fitnessindicator, scientists invoke a handicap principle.

　　睪丸素产生的特征，通常会被我们 认定为很有男子气概。这些特征包括浓眉、瘦脸颊、较大且方形的下颌。但这里有个很迷人的讽刺。在许多物种中，睪丸素的增加反而会抑制免疫系统。所以认为睪丸素 所赋予的特征是强健的指针，其实不是很有道理。在这里，逻辑被颠覆了。科学家提出了一条 生理缺陷原则，指出睪丸素并非强健的指标。

　　The most commonly cited example of ahandicap is the peacock's tail. This beautiful but cumbersome tail doesn'texactly help the peacock avoid predators and approach peahens. Why should suchan extravagant appendage evolve? Even Charles Darwin, in an 1860 letter to AsaGray wrote that the sight of the peacock's tail made him physically ill. Hecouldn't explain it with his theory of natural selection, and out of thisfrustration, he developed the theory of sexual selection.

　　最常被引用的生理缺陷例子，就是孔雀的尾巴。这美丽但累赘的尾巴 并不能帮助雄孔雀 避开猎食者，也不方便接近雌孔雀。为什么这种奢华的附属品会被演化出来? 即使达尔文，在 1860 年写给 阿萨格雷的信上也提到，看见孔雀尾巴会让他 感到身理上的不舒服。他无法用他的天择说来解释原因，出于这挫折，他发展出了性择说。

　　On this account, the display of thepeacock's tail is about sexual enticement, and this enticement means it's morelikely the peacock will mate and have offspring. Now, the modern twist on thisdisplay argument is that the peacock is also advertising its health to thepeahen. Only especially fit organisms can afford to divert resources to maintainingsuch an extravagant appendage. Only especially fit men can afford the pricethat testosterone levies on their immune system. And by analogy, think of thefact that only very rich men can afford to pay more than $10,000 for a watch asa display of their financial fitness.

　　由于这个原因，孔雀展示尾巴的目的是性诱惑，这种诱惑意味着这孔雀 很可能想交配、想生育后代。换个现代的角度想，雄孔雀是在向雌孔雀展现牠的健康。只有特别强健的有机体才有资格传宗接代，并保有这奢华的附属物。只有特别健康的人，才承担得起睪丸素 抑制免疫系统的风险。举个类似的现实例子，只有超级富翁才有能力买支 超过一万美金的手表，来彰显他们的经济实力。

　　Now, many people hear these kinds ofevolutionary claims and think they mean that we somehow are unconsciouslyseeking mates who are healthy. And I think this idea is probably not right.Teenagers and young adults are not exactly known for making decisions that arepredicated on health concerns. But they don't have to be, and let me explainwhy.

　　许多人听到这类的演化主张，就会想，是不是这个原因，我们人类会下意识地 去寻找健康的配偶。我认为这个想法可能不太对。青少年和年轻人容易被看上的原因，并不完全是他们健康条件上的优势。他们也不想这样，让我来解释原因。

　　Imagine a population in which people havethree different kinds of preferences: for green, for orange and for red. Fromtheir point of view, these preferences have nothing to do with health; theyjust like what they like.

　　想象有一个族群，族群中的人有三种偏好： 有人偏好绿色、有人偏好橘色、有人偏好红色。从他们的观点，这些偏好与健康无关; 他们就是喜欢这颜色。

　　But if it were also the case that these preferencesare associated with the different likelihood of producing offspring -- let'ssay in a ratio of 3:2:1 -- then in the first generation, there would be 3greens to 2 oranges to 1 red, and in each subsequent generation, the proportionof greens increase, so that in 10 generations, 98 percent of this populationhas a green preference.

　　但如果我们人类对这些颜色偏好的比率 也刚好与产生后代的有关…... 假设原来的比率是 3:2:1…...那么，在第一代中，会有三个绿色、两个橘色、一个红色。在后续的每个世代中，喜欢绿色的比例会增加，在十代之后，这个族群中就有 98% 的人都偏好绿色。

　　Now, a scientist coming in and sampling this populationdiscovers that green preferences are universal. So the point about this littleabstract example is that while preferences for specific physical features canbe arbitrary for the individual, if those features are heritable and they areassociated with a reproductive advantage, over time, they become universal forthe group.

　　现在来了一个科学家，对这个族群进行抽样，发现对绿色的偏好是很普遍的。这个小小的纯理论例子的重点是，虽然对于特定身体特征的偏好可能是因人而异的，但如果那些特征是有遗传性的，而且与繁殖优势有关联的话，随时间过去，这些特征就会变成团体的普遍现象。

　　So what happens in the brain when we seebeautiful people? Attractive faces activate parts of our visual cortex in theback of the brain, an area called the fusiform gyrus, that is especially tunedto processing faces, and an adjacent area called the lateral occipital complex,that is especially attuned to processing objects.

　　所以，当我们看见美丽的人时，头脑中会发生什么变化? 有吸引力的脸孔会触发 我们的部份视觉皮层，它位在大脑的后方，这个区域叫做梭状回，专门用来处理脸孔信息，还有一个相邻的区域，叫侧枕叶复合体，它是特别用来处理对象信息的。

　　In addition, attractive facesactivate parts of our reward and pleasure centers in the front and deep in thebrain, and these include areas that have complicated names, like the ventralstriatum, the orbitofrontal cortex and the ventromedial prefrontal cortex. Ourvisual brain that is tuned to processing faces interacts with our pleasurecenters to underpin the experience of beauty.

　　此外，具吸引力的脸孔会触发位在我们大脑前方深处的 奖赏与快感中枢，包括一些名称复杂的区域，比如腹侧纹状体、眼眶额叶皮质、及腹内侧额叶。我们用来处理脸孔的视觉大脑 会和我们的快感中枢互动，强化对美感的体验。

　　Amazingly, while we all engage with beauty,without our knowledge, beauty also engages us. Our brains respond to attractivefaces even when we're not thinking about beauty. We conducted an experiment inwhich people saw a series of faces, and in one condition, they had to decide ifa pair of faces were the same or a different person.

　　但惊人的是，当我们「遇见」美丽时，却不知道，美丽同时也「遇见」了我们。即使我们没有想着美，我们的大脑却会对 有吸引力的脸孔做出反应。我们做了一个实验，让人们看一系列的脸孔，在一个条件下，他们得要判定一对脸孔是否属于同一个人。

　　Even in this condition,attractive faces drove neural activity robustly in their visual cortex, despitethe fact that they were thinking about a person's identity and not theirbeauty. Another group similarly found automatic responses to beauty within ourpleasure centers. Taken together, these studies suggest that our brainautomatically responds to beauty by linking vision and pleasure. These beauty detectors,it seems, ping every time we see beauty, regardless of whatever else we mightbe thinking.

　　即使在这个情况中，有吸引力的脸孔会明显地驱动 受测者视觉皮层的神经活动，尽管当时他们在想的是人的身份，而不是他们美不美。另一群人也有类似发现，在我们的快感中枢里，我们对美会有自动的反应。整体来看，这些研究指出，我们的大脑会藉由视觉和快感的链接对美会自动的反应，似乎，每回当我们看到美时，这些对美有反应的侦测器就会响起，不论我们当时在想什么其它的事。

　　We also have a "beauty is good"stereotype embedded in the brain. Within the orbitofrontal cortex, there'soverlapping neural activity in response to beauty and to goodness, and thishappens even when people aren't explicitly thinking about beauty or goodness.Our brains seem to reflexively associate beauty and good. And this reflexiveassociation may be the biologic trigger for the many social effects of beauty.Attractive people receive all kinds of advantages in life. They're regarded asmore intelligent, more trustworthy, they're given higher pay and lesserpunishments, even when such judgments are not warranted.

　　我们脑中也内建了一个 「美等于好」的刻板印象。在眼眶额叶皮质中，对于「美」及「好」 所造成的神经活动反应 是有重迭性的，即使人们没有特别去想着美或好，也会发生。我们的大脑似乎会反射性地把美与好连结在一起。社会上因「美」而产生的回馈，其背后的关联性可能就是 这些生物触发器在驱动。有吸引力的人，在人生中有各种优势。他们会被视为比较聪明，比较值得信赖，他们会比较高薪、比较少受惩罚，即使这类的判断是没根据的。

　　These kinds of observations reveal beauty'sugly side. In my lab, we recently found that people with minor facial anomaliesand disfigurements are regarded as less good, less kind, less intelligent, lesscompetent and less hardworking. Unfortunately, we also have a "disfiguredis bad" stereotype. This stereotype is probably exploited and magnified byimages in popular media, in which facial disfigurement is often used as ashorthand to depict someone of villainous character. We need to understandthese kinds of implicit biases if we are to overcome them and aim for a societyin which we treat people fairly, based on their behavior and not on thehappenstance of their looks.

　　观察到这种现象 也揭露出美的丑陋面。在我的实验室中，我们最近发现 有轻微面部异常及缺损的人，会被认为比较不好、比较不仁慈、比较不聪明、比较没能力、且比较不努力。不幸的是，我们也有「缺损等于不好」的刻板印象。大众媒体的影像可能会利用和放大 这种刻板印象，他们常用「面部缺损」 这种简单的描绘方式 来形容反派人物。我们需要了解这类的暗示性偏见，才有可能克服它们，并朝向一个能平等待人的社会迈进，不要只是看一个人的外表就断定人的好坏。

　　Let me leave you with one final thought.Beauty is a work in progress. The so-called universal attributes of beauty wereselected for during the almost two million years of the Pleistocene. Life wasnasty, brutish and a very long time ago. The selection criteria forreproductive success from that time doesn't really apply today.

　　让我留给各位一个最后的思考。美的定义还在改变。所谓放诸四海皆准的美的特征 是从几乎两百万年的 「更新世」所挑选出来的。那时生命很糟糕、很粗野、很古早。当时能繁衍成功的选择标准在现今并不适用。

　　For example, death by parasite is not oneof the top ways that people die, at least not in the technologically developedworld. From antibiotics to surgery, birth control to in vitro fertilization,the filters for reproductive success are being relaxed. And under these relaxedconditions, preference and trait combinations are free to drift and become morevariable. Even as we are profoundly affecting our environment, modern medicineand technological innovation is profoundly affecting the very essence of whatit means to look beautiful. The universal nature of beauty is changing even aswe're changing the universe.

　　比如，因寄生虫而造成死亡 并不是人类前几名的死因，至少在技术发达的世界中不是。从抗生素到手术，从生育控制到试管授精，繁殖成功的过滤器已经被放宽了。在这些放宽的条件下，偏好与特性的组合可以自由搭配，也变得更多样性。即使我们会深深影响我们的环境，现代医学及技术创新会深深影响着 我们对美的定义。即使我们正在改变全世界，普世价值对美的定义也在改变。

　　Thank you.(Applause)

　　谢谢大家。(掌声)