The accents that creep into the way we speak can reveal a lot about where we are from， but there are also subtle clues visible in our faces and the way we move.

While leafing through some old research papers， Hillary Elfenbein noticed something strange about the photographs in one famous study. The research from the late 1980s had asked volunteers if they were able to identify emotions in the faces of Japanese and Caucasian people. Some of the “Japanese” faces were posed by Japanese-Americans， the rest by Japanese nationals.

When Elfenbein herself looked at photographs， she realised that she could tell which were which. Her collaborator， Abby Marsh， found that she could too. So they ran an experiment.

They found that the Americans they tested were also strangely good at spotting who was Japanese and who was Japanese-American， even though they were all ethnically the same. When the two groups held neutral expressions， people could barely differentiate between them. But when they showed their feelings， especially sadness， something from Japan or America seemed to emerge.

You may have had this experience yourself， if you’ve ever been abroad and felt suddenly convinced that a passing stranger is one of your fellow countrymen. At times the signal may be obvious.

If you’ve seen the film Inglourious Basterds， you will know that German and British people indicate the number three with their fingers in different ways. Germans raise their thumb and first two fingers; Britons pin the little finger with their thumb and raise the rest. Most never realise that this difference exists until they see the alternative， which， to them， looks strange.

Some signals may be random quirks that happened to catch on. Others may have served a purpose. Vladimir Putin is said to display his KGB weapons training in the way he walks， with his “gun arm” hanging motionless by his side.

Since their initial discovery， Marsh and Elfenbein have detected more of these “non-verbal accents” physical ways in which we show where we come from without realising. Americans， for example， can spot Australians from the way they smile， wave or walk.

More recent research supports their findings. A team at the University of Glasgow has now trained a computer to recognise and then generate more than 60 different non-verbal accents on a simulated face. Subtle， almost indecipherable differences in the way a nose wrinkles and a lip is raised were often all that differentiated them. But when East Asians were shown these artificial “East Asian” expressions， they recognised them much more easily than “Western” ones.

The presence of these subtle cues might help to explain the bias that can creep into our thinking about people from different backgrounds. As we’ve seen， non-verbal accents often have the effect of making outsiders more difficult to understand.

At the very least， when people really want to understand each other， non-verbal accents show us that it’s good to talk.

我們說(shuō)話時(shí)不經(jīng)意間流露出的口音很大程度上會(huì)暴露我們是哪里人，但從我們的表情、手勢(shì)和走路姿勢(shì)也可以察覺(jué)到微妙的線索。

在翻閱一些舊論文時(shí)，希拉里·埃爾芬拜因注意到一項(xiàng)著名研究的照片中有一些奇怪的東西。上世紀(jì)80年代末的這項(xiàng)研究詢問(wèn)志愿者是否能識(shí)別日本人和高加索人臉上的表情。一些長(zhǎng)著“日本臉”的人是日裔美國(guó)人，其余的是日本人。

當(dāng)埃爾芬拜因觀察那些照片時(shí)，她意識(shí)到自己能辨認(rèn)出哪些是日裔美國(guó)人，哪些是日本人。她的合作者艾比·馬什發(fā)現(xiàn)她也可以。于是她們就開(kāi)展了一項(xiàng)實(shí)驗(yàn)。

她們發(fā)現(xiàn)，接受測(cè)試的美國(guó)人也不可思議地善于辨別日本人和日裔美國(guó)人，即使二者是同一種族。當(dāng)兩個(gè)群體都面帶中性表情時(shí)，人們幾乎難以區(qū)分。但當(dāng)他們開(kāi)始表露情緒，尤其是悲傷情緒時(shí)，日本或美國(guó)的一些特質(zhì)就開(kāi)始顯現(xiàn)出來(lái)。

你自己也許也有過(guò)這種經(jīng)歷，如果你曾經(jīng)出過(guò)國(guó)，突然間很確信走過(guò)你身邊的一個(gè)陌生人就是你的同胞。有時(shí)候這種信號(hào)也許很明顯。

如果你曾看過(guò)電影《無(wú)恥混蛋》，你會(huì)知道德國(guó)人和英國(guó)人用手指表示數(shù)字3的方式是不同的。德國(guó)人豎起大拇指、食指和中指，而英國(guó)人用大拇指壓住小指，豎起其他三根手指。多數(shù)人從未意識(shí)到這種差異的存在，直到他們發(fā)現(xiàn)另外一種方式，在他們看來(lái)，這種方式很奇怪。

一些信號(hào)可能是偶然習(xí)得的一種隨意的怪癖，而其他的信號(hào)也許是有用處的。據(jù)說(shuō)從弗拉基米爾·普京的走路姿勢(shì)可以看出他接受過(guò)蘇聯(lián)國(guó)家安全委員會(huì)（克格勃）的武器訓(xùn)練，因?yàn)樗侵弧俺謽尩氖帧辈粫?huì)擺動(dòng)。

自從有了初步發(fā)現(xiàn)后，馬什和埃爾芬拜因察覺(jué)到了更多這種“非言語(yǔ)特點(diǎn)”，這種肢體特點(diǎn)在我們不經(jīng)意間暴露出自己是哪里人。舉例而言，美國(guó)人可以從笑、招手或走路的方式識(shí)別出澳大利亞人。

新近的研究也支持了她們的發(fā)現(xiàn)。格拉斯哥大學(xué)的一個(gè)團(tuán)隊(duì)現(xiàn)在訓(xùn)練一臺(tái)電腦識(shí)別并在一張模擬人臉上生成60多種不同的非言語(yǔ)特點(diǎn)。像皺鼻子、翹嘴這種幾乎無(wú)法辨認(rèn)的微妙差異往往就是識(shí)別的關(guān)鍵。但是東亞人識(shí)別“東亞”表情比識(shí)別“西方”表情要容易得多。

這種微妙線索的存在也許有助于解釋對(duì)來(lái)自不同背景的人們不自覺(jué)產(chǎn)生的偏見(jiàn)。正如我們所看到的，非言語(yǔ)特點(diǎn)往往會(huì)讓人們更難以理解外國(guó)人。

不過(guò)，起碼當(dāng)人們真的想理解對(duì)方時(shí)，非言語(yǔ)特點(diǎn)向我們展示了開(kāi)口交談的好處。