Many people wander through a world littered with white lies, the social niceties freshening up the atmosphere of necessary interaction. “Love those earrings,” you might say when trapped in an elevator with your boss. “Delicious,” you tell your boyfriend who has handed you a cup of weak and too-sugary tea. You might think these conversational accessories cost you nothing, but those who indulge in sugar-coated sentiments may be paying an invisible price — suspicious that others are guilty of the same less-than-perfectly-honest behavior, they may be robbing themselves of the pleasure of believing a simple compliment bestowed for no reason.

On the whole, it’s difficult to begrudge small lies told for the purpose of perking up the workplace or pasting a smiley face on the outer world. What most of us want to avoid, though, are big lies and big liars — compulsive or pathological liars spreading false statements and causing real damage. There’s a big difference between sweetening a momentary interaction and true self-gain, after all. Did she radically inflate her job application? Is he a total cheater? These are real concerns with real consequences and everything you want to avoid. To improve your lie detection abilities, the first step is reviewing what you've been told.

Eye Movements?

People often say eye movements are one way to spot a liar, and beneath this claim are ideas of right brain-left brain functioning. As the theory goes: A person looks up to the right when visualizing an imagined event (lying), and looks up to the left when visualizing a remembered event (telling the truth). For a 2012 study, an international team of researchers investigated these ideas in order to find the truth.

In their first experiment, the researchers instructed participants to either lie or tell the truth (chosen by coin toss) when questioned by an interviewer in a room where they were videotaped. After mapping eye movements and analyzing the data, the researchers did not find any patterns. In a second experiment, the researchers divided the participants into two groups and told one group about the eye-movement theory before all the participants underwent the same test. Yet the results came up exactly the same: no detectable patterns.

Because these are no-stakes laboratory experiments, the researchers conducted a third high-stakes experiment where they coded the eye movements in 52 video tapes of people making a public plea for the safe return of a missing relative. In roughly half of these videos, strong evidence suggested they had been lying (due to evidence subsequently turning up, and in some of the cases discoveries they were the perpetrator of the crime). Once again, though, the researchers did not uncover any telling eye movements to indicate the presence of a lie.

So, what lie detection technique actually works? A collection of UK researchers hypothesized that skin temperature might do the trick.

Close Enough?

To test their theory, the team recorded the skin temperature of 51 passengers in an international airport departure hall who either told the truth or lied about their forthcoming trip in an interview. The researchers discovered skin temperature rose significantly for liars during the interview, while the skin temperature of truth tellers remained constant. Then, using the results of this temperature test, the researchers correctly classified 64 percent of truth tellers and 69 percent of liars in a subsequent experiment. Yet when the interviewers themselves assessed the passengers, without using the results of thermal recordings, they correctly identified truth tellers 72 percent of the time and liars 77 percent of the time.

In other words, human instinct beat scientific technique in this circumstance. Meanwhile, another group of researchers, possibly influenced by the eye movement technique, theorized that deciding who is lying and who is tellng the truth all comes down to how frequently a person blinks. For their experiment, they sent 32 participants to deliver a package to an interviewer and told 17 of the participants to lie about this mock mission. During the interview, the researchers used video cameras (and other technologies) to collect data on how often the participants blinked their eyes.

What did the researchers discover? Liars blink less often than truth tellers, who in fact increased their blinking when answering questions. In fact, using eyeblink suppression to predict lying in another test case, the researchers correctly classified the liars 81.3 percent of the time. Because this technique could be used secretly by using webcams and hidden cameras, the researchers believe their technique has great promise for the future. Good for them, but most people prefer to upgrade their lie detection abilities minus the equipment.

Observation

A U.S.-based team of researchers reviewed a boatload of past studies to find simple, observable behaviors to identify liars. Analyzing the data, they discovered one reliable indicator of lying is the relatively smaller number of details provided in an account when compared to truth tellers. In fact, the stories told by liars generally made less sense and were told in less engaging and less immediate ways. (For instance, liars often avoided using personal pronouns.) Compared to truth tellers, liars also sound less involved, less immediate, and more uncertain. Nervousness and tension are also hallmarks of lying; most of us, though, can only detect unnatural behavior in the people we know best. There are a collection of other details that might be difficult to spot. For instance, people making up lies are more vocally tense and speak in a higher pitch, plus they have more dilated pupils.

There's one physical detail, though, that both gives away the lie and is easy to spot: Liars tend to raise their chins.

For those who like unorthodox methods, the best way to learn to detect liars may be to become one (briefly) yourself. In a London-based study, the researchers discovered the oldest truth of all: Better liars make better lie detectors. You can’t kid a kidder.