The Truth Is, Spotting a Lie Isn't As Easy as It Looks

By Neely Tucker
Washington Post Staff Writer
Sunday, February 15, 2009

Science is closing in on humanoids and their seedy necessity to lie about almost everything, but don't worry. We've had tens of thousands of years of practice at it, and until you stick your head inside a machine that plays with the protons in your brain so that it can film the neurons firing in your prefrontal cortex, you can probably get away with it.

Neurological research is showing that lies are so interwoven into our central nervous systems that it's not even an unnatural act. Lies require work in at least five sections of the brain, and to separate them from the truth requires machinations that make rocket science look like 2 + 2. Otherwise, lie and truth are indistinguishable.

"Lying is ubiquitous" in the brain, says Ruben C. Gur, one member of a team at the University of Pennsylvania that is using short films of the brain, called "functional Magnetic Resonance Imaging," to detect lies. If lies "were contained in one section of the brain, it would be worn out at the end of the day."

Hence the fascination, as displayed in the new Fox television series "Lie to Me," of our near mystical belief that we might somehow learn to parse fact from fiction by sight and sense alone. That we, as mere human beings, can tell when we are being told a lie.

"Lie to Me" follows the fictional Dr. Cal Lightman, "the world's leading deception expert," who has the ability to determine who is lying and why through a scary-good reading of body language and facial expression. The show's tagline asserts that "the truth is written all over our faces," promising that people are literally lying to your face and you don't even know it.

The show, which comes across as sort of silly, is based on the entirely serious work of Paul Ekman, the famed psychologist and author, who sold Fox his professional life rights for the series and acts as its consultant. Ekman, 75, has spent more than four decades studying nonverbal communication and its sexy sidekick, truth detection.

From his professorial perch at the University of California at San Francisco, he's written more than a dozen books, including "Telling Lies" and "Emotions Revealed." The American Psychological Association named him as one of the most influential psychologists of the 20th century. His firm runs seminars for people -- say, security staffers at airports -- who want to study his "micro-expression expression training tool" system to see who might actually be dangerous.

Here's the kicker: You can't.

No, really. You can't.

"We've been testing people's ability to discern a lie for 15 years now and haven't noticed any real change over that time," he says in a telephone interview. "We've tested about 15,000 people in every profession you can think of -- CIA, judges, lawyers. Less than 1 percent are any good at it. Most people are only at about the level of flipping a coin."

He writes: "Most liars can fool most of the people most of the time."

He says that you might become pretty good at lie detection, with training, but only in your professional life. Even federal investigators who run a crisp interrogation are lousy at picking out lies at home.

"Cops tend to do well in detecting lies about theft, and therapists tend to do better about lies about emotion," says Maureen O'Sullivan, a professor of psychology at the University of San Francisco who often works with Ekman. "But in their personal lives, they can be complete dolts."

Here's a little bon mot, from the research files.

One of the most common thing people do in hiding emotions, Ekman notes, is to smile. So let's say you notice someone very quickly tighten their lips (a highly reliable sign of anger) and then smile. They are actually baring their teeth.

* * *

Let's go burrowing in the brain. Let's look at how lies get started.

Neuroscientists like Gur and research partner Daniel Langleben have spent the past decade learning to spot lies bopping around the bumps and grooves of the brain. Their fMRIs are the hot new thing in truth detection.

By using extremely controlled conditions -- keeping the test subject's head perfectly still, limiting the selection of answers, forcing the subject to answer by pressing a button, asking hundreds of carefully prepared questions -- they can spot truthful and dishonest responses with an accuracy rate north of 90 percent. It is not just that the brain uses more energy to tell a lie, Langleben says, but that the response pattern is visibly different, at least during the highly structured questionnaire.

Their finding is revolutionary is at least one aspect: It demonstrates that lies exist (a) in a distinct physical form and (b) those forms are replicated across people of different ages, races and religious backgrounds.

In other words, when we lie, our brains process it in a way different from the truth. Enter Ekman.

For four decades, he has videotaped thousands of people of all ages and cultural backgrounds when they are telling the truth, lying or just telling a narrative story. He has broken emotions into seven universal headings: anger, fear, disgust, contempt, surprise, sadness and happiness. From his data, he created a taxonomy for body movements (emblems, illustrations, manipulations) that can reveal or hide these emotions as well as a vast catalogue of facial movement. He identified possible interpretations of all these, the two main ways of lying (concealment and falsification) and the different emotions in lying (guilt, fear of getting caught, delight in fooling the subject).

He discovered what poker players would call "tells," or unconscious indicators of emotion. For example, tightening the lips is one of the most reliable signs of anger because it is so physically hard to do, Ekman says, and often takes place before people are aware that they're doing it.

To get at the truth, let's break down how you use your body to talk.

First, there are "emblems," such as the "thumbs up" gesture, which is recognized to mean "Okay!" Emblems are helpful in truth detection, but only when they are arrested in mid-gesture: shrugging one shoulder, starting to raise and flap your hands away from yourself, as if to say, "Oh, I'm finished with that" -- but halting the gesture. Your body just told the truth before you could stop it. These are "emblematic slips," Ekman says, and indicate the subject is trying to suppress or alter information.

Second, there are "illustrations," such as waving your arms or jabbing a finger in the air. Illustrations decrease when people tell lies because liars are being careful and unconsciously inhibiting their motions.

Last are "manipulations," which are personal grooming tics, such as biting your fingernails. Manipulations, it turns out, don't mean anything one way or the other -- and yet studies show most people list these tics as one of the clearest signs of dishonesty. They're not. People who read them are committing an "Othello error," in Ekman's jargon, a reference to the Shakespearean character who falsely believed his wife to be an adulteress.

These interpretational errors are so profound, Ekman says, that one of his main concerns with the show is that, "We don't want jurors thinking that because they saw 'Lie to Me,' that they can tell when someone on the stand is lying."

He adds, "It takes us two to four days in law enforcement training to get any sort of improvement. The 1 percent who are really good at it, we call 'wizards.' "

Now here's the twist: Truth is not the only issue that's important. Trust counts, too.

At the Massachusetts Institute of Technology's Media Lab, researchers study the physical dynamics of human interactions. Their studies show that body language, vocal pattern and pitch are so critical to human trust that they can predict the success or failure of a sales pitch by reading body language and vocal patterns alone. They don't even need to know what you're saying to know if the other person is likely to trust it.

With a device called a sociometer, project director Alex Pentland detects if you are looking at the person you're talking to, and a recorder tracks the timing, speed and inflection of speech (but not the content).

It turns out that people who use positive body language and correct vocal inflection -- nodding heads in agreement, leaning forward in their chairs, speaking in the same vocal range and speed as conversational partners -- will win other people's trust.

"The background of this is our human communication from 50,000 or 100,000 years ago, when we didn't have that many words, but were still able to communicate and coordinate very closely," he says. "We're still extraordinarily sensitive to socially appropriate behavior, but it's so deeply buried that we are almost unconscious of it."

Then again, this just describes body language that honest people tend to use. It doesn't mean dishonest people couldn't ape that behavior to lie to you.

In the end, "truth wizards" -- the 1 percent or so of people who can see past all this to discern lies really well -- have a unique ability to keep their minds open, O'Sullivan says. "They don't hurry to a conclusion. They'll live with indecision. Most of us don't want to do that, including me. People want certainty."

She laughs and says: "I want things to be nice."

And this is the problem, she notes: Things are often not nice, and yet people who should know better ignore or look past the unpleasantness of the facts to see a happier version of reality and to keep things, you know, nice. Besides, to constantly double-check the information your friends and family gives you might uncover more of the truth about some things, but what you'll really be communicating is that you do not find them worthy of your trust. "Show me" might be a nifty motto for Missouri, but it's a lousy one for a marriage.

"People really don't want to know all the truth all the time," O'Sullivan says.

"No important relationship survives if trust is totally lost," Ekman writes.

So there it is. Absolute truth is doomed because the search to ferret it out would ultimately be so consuming as to eradicate trust, which is the far more solid building block of human relationships.

It turns out that we only want the truth sometimes. What we need is trust, even if that means we are certain to be betrayed. It is, as any fMRI can show you, the human condition.

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