If you think your guy's lying to you based on his eye movements, you better think again. A new study published in the journal PLoS ONE debunks the widespread notion that you can tell a person is lying by the way his eyes move. Apparently, eye movement is not a good indicator of deception.

According to practitioners of neuro-linguistic programming (NLP), a person whose eye shifts to the left means he’s remembering something, while a shift to right means he’s not telling the truth. Researchers from Edinburgh University and Hertfordshire University conducted a series of experiments to put the neuro-linguistic programming (NLP) credo to the test. For the first phase, they recruited 32 right-handed participants (The NLP lie detection theory is based on right-handed persons only) and videotaped them as they either lied or told the truth. Upon later analysis, there appeared to be no connection between eye movement and the truthfulness of the participants’ statements.

In another experiment, researchers showed 50 volunteers the video shot earlier. Half of them were randomly given information on NLP lie detection techniques, while the other half remained oblivious. They were then instructed to identify which people were telling the truth and which weren’t. Based on the results, researchers found no link between eye movement and truth-telling. There was no significant difference in the accuracy rating of those who were briefed on NLP and those who relied on their natural instincts.

For the last experiment, researchers watched videos of 52 people appealing for help in finding their loved ones. Some of the people in the video were known to be lying, but once again, the researchers failed to discern which people were lying and which weren’t through NLP techniques. The link between eye movement and the statements remained non-existent.

So is the eye movement theory well and truly debunked? Not exactly. Howard Ehrlichman, a professor emeritus of psychology at Queens College of the City University of New York, believes that there may be something more to eye movement than most people realize. In an interview with ABC News, he says, "I found that while the direction of eye movements wasn’t related to anything, whether people actually made eye movements or not was related to aspects of things going on in their mind."

Apparently, any eye movement is an indicator that a person is processing something from long-term memory. "If there’s no eye movement during a television interview, I’m convinced that the person has rehearsed or repeated what they are going to say many times and don’t have to search for the answer in their long-term memories," Ehrlichman said.

(Photo by John O'Nolan via Flickr Creative Commons)