“Looking for the Lie”
by Robin Marantz Henig
The New York Times Magazine, February 5, 2006
A picture of a brain caught in mid-lie – that’s pretty hard to resist. Think of all the liars you’d love to expose: criminals, terrorists, politicians, philandering spouses, drug- abusing kids. That’s why scientists are trying to develop ways to unmask liars with techniques that go beyond traditional polygraphs – which are notoriously imprecise – or simple hunches – which are notoriously wrong. The next generation of lie detectors will include functional MRI scans, sophisticated electroencephalograms, and beams of light that can be blasted right inside the brain.
But as we move closer to an era of high-tech mindreading, we should first take a look at what we know about lying – and whether it’s always such a good idea to uncover it. Is there an evolutionary purpose to deceit? A social purpose? Can anyone live in a community in which lies are always exposed and eliminated? If we can tell with confidence that someone is lying to us, is that something we even want to know?
I’d like to propose a piece about lying for the Magazine, either as a 5000-word feature or as a longer cover story that gives me the space to explore the cultural, biological, and evolutionary implications of deception. I will also ask some of the questions raised with any new medical technology: what it can offer, how it can be abused, and whether it will set us off down a “slippery slope” that will lead to information we’d be better off without.
On the pro side of techniques like lie-detector fMRIs is that they can’t be outsmarted the way polygraphs can. Polygraphs are measurements of the guilt-induced anxiety of lying, as indicated by increases in blood pressure, heart rate, and sweating. But what if you’re a liar who just doesn’t feel bad about it? To a polygraph, you’d be telling the truth. With fMRIs, according to proponents like Dr. Scott Faro of Temple University’s Functional Brain Imaging Center, nothing can be faked: it requires more cognitive effort to lie, no matter who you are, and that’s what these brain scans are measuring.
But the danger of fMRIs is just that: they seem so precise, so scientific, so pure. That makes it seem as though any result from an fMRI, or from a similar picture like a PET scan or a thermal scan (also being developed as lie detectors), is incontrovertible. But is a brain picture all that matters? Say a white man who claims racial tolerance is shown a range of faces, and his fMRI scan always shows a negative response when the faces are black. (It’s happened, in research done at Dartmouth in 2003.) How would the man respond to such insight into his own heart? What about his potential employers?
Would such information be relevant if he were, say, applying to be a teacher in a high- minority school in the south Bronx, or a police officer in downtown Detroit? Is this man a racist, as his brain scan suggests? Or is he a fair and tolerant person, as indicated by his words and his behavior?
Or say a doctor knows about someone’s true, dire prognosis, and chooses not to tell the patient because of fear of taking away the patient’s hope. Or a woman knows her best friend cheats on her taxes, or has a drinking problem, or hates her sister-in-law — but chooses not to tell anyone? Must these lies be uncovered, or are they motivated by impulses that make them acceptable?
The ACLU is already complaining that high-tech lie detectors will lead to “a surveillance society, where every action, every deed and one’s very thoughts can be monitored, categorized and correlated.” But the real, troubling questions go beyond the ones about Big Brother – and beyond simple lie detection, to all sorts of ways that scientific information can force us to re-define truthfulness itself. DNA tests, for instance, can now reveal to you that the man you always thought was your father, the man who raised you, the man married to your mother, isn’t your real father at all. Is it always best to know the truth?
Some people can’t help but know when they’re being lied to – they have some sort of inborn lie-detector that clicks on whether they want it to or not. Paul Ekman, a psychologist at UCSF and the author of the classic Telling Lies, has studied these “wizards of deception detection” to try to figure out what it is they see that the rest of us don’t. According to Ekman, they’re responding to a speaker’s involuntary microexpressions, which no one, not even skilled liars, can consciously control. These microexpressions flit by in as little as one-fifth of a second, and they are the true indicators of someone’s emotional state. And when they contradict the forced, voluntary expression on a speaker’s face, you can bet that person is lying. “The mouth may lie,” wrote Friedrich Nietzsche, “but the face it makes nonetheless tells the truth.”
Ekman has developed a Facial Action Coding System, which parses facial expressions into 43 elements, or “action units,” arranged in about 3,000 possible combinations. He now has a busy consulting hobby in which he trains police investigators, FBI agents, and counter-terrorism experts to read faces using the coding system in order to spot a potentially dangerous liar.
The truth about microexpressions helps explain the observation that the best liars are those who actually believe their own lies. Robert Trivers, a psychologist at Rutgers, has explored this idea from an evolutionary perspective. He begins with the assumption that natural selection favors organisms that practice deception: a prey that looks like a
predator, a moth that looks like a leaf, a female that convinces a male that her offspring is his. But natural selection also favors organisms that can detect deception, so that the predator finds the prey and the male does not work hard to feed a baby that isn’t his.
The most successful organism, Trivers says, is one that not only lies, but lies convincingly. And the one most likely to lie convincingly is the one who believes his lie to be the truth. Trivers is currently working on a book for Viking Penguin developing this theme.
A lie is nothing more than “the truth in masquerade,” wrote Lord Byron (in one of hundreds of quotes about lies amassed on the web site of Dr. Jennifer Vendemia, a psychologist at the University of South Carolina working on a truth machine with funding from the Pentagon). I’d like to explore the various ways in which that masquerade can be attempted, and unmasked.