It is the nervous tick that tips off the detective to the lie.

The biting of the lips, the constant grooming of the hair and the faint hint of nervous perspiration all indicate that this suspect knows more than he’s actually saying.

“He’s lying,” a TV detective says. “He knows who the murderer is.”

And just like that, the case has been broken open, the detective’s smooth skills penetrating through the suspect’s deceptive front, ensuring justice for another night.

But outside of the Hollywood world, the art of detecting a lie is much less simple, said Edward Geiselman, a professor of psychology at UCLA and a leading researcher in the study of deception.

Geiselman has been working to discover the requirements for training everyday individuals in detection of deception. His most recent work was published last week as an article in the American Journal of Forensic Psychiatry.

Such methods provide the hope that law enforcement and national security personnel could join the ranks of the few true experts who can detect a lie with high accuracy.

But a brief training in lie indicators actually led participants to do worse in deception detection.

Using UCLA students as test subjects, the professor and his research team set out to determine the effectiveness of lie detection training on the ability to spot deception.

Geiselman and his research team compiled a list of some of the most reliable indicators that someone is telling a lie. These indicators fell into four general categories: verbal indicators, motivation expressions, vocal indicators and behavioral indicators.

The experiment began by recording students’ opinions on four different topics, such as marijuana legalization and the death penalty, said Sandra Elmgren, a co-author of the article and UCLA alumna. The students would give their true opinions on one topic while lying on another.

These recordings were then shown to another set of participants who were asked to judge whether the opinions of the recorded students were truthful or deceptive, without having any prior information on lie detection indicators.

Afterwards, the second set of participants were given a handout describing some of the prominent signs of deception. They were told they had a night to become familiar with the material, and were then asked to re-evaluate their judgments about the truthfulness of the statements.

“We wanted to see if there was any improvement (after the brief training) from the first time they saw the recordings,” said Ida Rystad, another co-author and UCLA alumna. With the training, the accuracy of participants in identifying deception was actually worse than when they purely relied on their gut feeling, said Simon Poulton, a fourth-year psychology student who works with the professor on developing training methods.

The problem, Geiselman found, is that a small amount of training in detecting lies made participants overanalyze the situation.

“One of the things the research shows us is that it is going to require an extensive training program, maybe four or five days worth of instruction in order to see the benefits of training; otherwise you might be better off without the training,” he said.

These findings have major implications for those who require deception detection in their line of work, such as law enforcement officials. For police officers, modern budget constraints have cut down on available training time, making it harder to enact extensive training programs. This inability to provide the necessary training could end up hurting them, Elmgren said.