Do polygraphs work? Not really, experts say. Use these tips instead.

测谎器有用么？并非如此，专家们说。不如使用以下秘诀。

On the cringe-inducing hit show The Moment of Truth, guests are shamed into horribly embarrassing admissions on national TV after taking a so-called lie-detector test.

在一个引介逢迎的节目秀《真相大白》中，客人们通过了一个所谓测谎试验之后，难堪地进入令人极其窘迫的国家电视。

But, truth be told, the polygraph is a crude tool that the esteemed National Research Council says has extremely serious limitations.

但是，实话说，测谎仪是一种拙劣的工具，连地位尊崇的国家研究委员会也说它有着"极端严重的限制"。

Polygraphy tests do not detect lies, says Frank Horvath, past president of the American Polygraph Association. They detect physiological arousal to psychological stimuli. That means the devices register a lie when the interview subject is just plain nervous.

"多波扫描器并不能测探到谎言，"美国多波图谱协会前会长弗兰克·霍法思说，"它只能探测到对于心理刺激所产生的生理应激。"这表示当测试的主题哪怕是平白地令人紧张的时候，这种仪器也会提示出撒谎。

Researcher Paul Ekman, author of Telling Lies: Clues to Deceit in the Marketplace, Politics and Marriage, contends that the best lie detectors are trained eyes and ears. He claims that when a person is telling a lie for the first time and it's a big one, he can detect the lie with near-perfect accuracy--and so can you. The trick is to figure out the verbal and non-verbal cues that are masking concealed emotions.

研究员保罗·埃克曼，是《说谎：在市场、政治和婚姻中的欺骗》一书的作者，他表示最好的测谎器当属素有训练的眼睛和耳朵。他宣称，当一个人第一次说谎并且是一个大谎的时候，他能够以几近完全的精确率探测出谎言来，而且你也能够这样。秘诀在于搞清楚那些笼罩着隐藏情感的语言和非语言的线索。

One of the telltale signs: inconsistencies, such as when someone is telling you no and shaking his head yes, or saying he regrets something while using an unremorseful tone.

其中揭秘的迹象有：矛盾不一，比如一个人告诉你说不是却又点头，或者说他后悔某事却是用一种并非懊悔的口吻。

New English research found another way to spot holes in a story: Ask the suspected fibber to recite his story backward--in reverse chronological order. You'll also discover contradictions in his behavior and speech.

新英国研究发现另一种办法来认定一篇说辞中的漏洞：请那个嫌疑撒谎者将他的故事以逆时间顺序倒述一遍，你会发现在他的行为和言辞间的一些矛盾之处。

Ultimately, the human brain is the best lie detector.

最终来说，人类的大脑才是最好的谎言探测器。