Since the beginning of time, it has been difficult to discern when someone is lying. Now, artificial intelligence may help scientists get closer to this goal.

A team of researchers from Tel Aviv University installed sensors on the faces of volunteers to detect subtle movements as they tell lies and truths.  

This system could detect lies with 73% accuracy. It is slightly lower than polygraph tests, which are accurate 80 percent of the time.

But, they claim that the current stage of development is only the beginning and that things will get better in the future.

The future will see AI-equipped cameras being used in interviews, online jobs and in police suspect interviews to determine if someone is lying. 

Being able to detect when someone is lying has been a goal for decades, and now, thanks to artificial intelligence, a team from Israel believe they may be getting close

It has been decades-long goal to be able to discern when someone lies. A team of Israeli scientists believes they are getting closer to that goal, using artificial intelligence.

What is the secret to it? 

Two groups of facial muscle muscles were attached with stickers by researchers who used their electrodes. 

  • Close to the lips, the cheek muscles
  • Move the eyebrows to the side of the eyes.

The participants were required to sit facing one another with the other wearing headphones. 

The wearer was lying when he said “tree”, but heard “line” and then said “tree”, or vice-versa. It was obvious that he was lying. 

The two subjects then switched roles.

It was not possible for participants to discern the lies of partners. 

However, 73% of lies were identified by electrical signals from electrodes placed on their faces.

Research has shown that people can distinguish lies from truth approximately 55% of the times. A polygraph machine, however, is accurate to up to 82%.

The results of the polygraph test are not sufficient to prove a person’s identity. Therefore, researchers around the globe have been working hard on innovative solutions. 

Tel Aviv’s project used machine learning and artificial Intelligence to analyse muscle movement changes during lies. 

This included small movements of the cheek muscles and of the eyebrows.   

The stickers were printed on smooth surfaces and contained electrodes that can measure nerves and muscles. 

Professor Levy stated that it was almost impossible to discern when someone lies to you. Experts, like police interrogators do not perform as well as the rest. 

‘Existing lie detectors are so unreliable that their results are not admissible as evidence in courts of law – because just about anyone can learn how to control their pulse and deceive the machine. 

‘Consequently, there is a great need for a more accurate deception-identifying technology. 

“Our study assumes that our facial muscles contract when we lie down, but that no electrodes are sensitive enough to detect these contortions.”

Researchers attached stickers to cheek muscles just below the lip and above the eyebrows. 

The volunteers were then asked to sit together in pairs, facing one another. After that, the words “line” or “tree” were said into their ears via headphones. 

Participants were told to lie to or reveal the truth about the word that they’d heard to their partner. 

Researchers attached stickers with special electrodes to two groups of facial muscles, above the lip and above the eyebrow. Volunteers then said a lie or a truth

The stickers were attached to the facial muscles by attaching special electrodes. These electrodes are above the eyebrow and the lip. The volunteers then said whether the truth was true or false.

STUDY FINDS: WE SPEAK LOWER IF WE’RE LIEING 

A 2021 study found that liars speak slower and place less emphasis in middle of words. 

Paris-based researchers claim that the brain detects a pattern in the speech of a lie by listening to slower words and putting less emphasis at the end of words.

It happens regardless of whether we are actively trying determine if someone honest. 

The police may use the information to create ‘light tools,’ which could help them determine if a suspect is lying.

Read more: Liars speak slowly and put less emphasis on the middle of words 

The wearer was lying when he said ‘tree’ and heard ‘line’. 

The results showed that participants could not detect the lies of their partners with statistical significance. 

However, 73% of all lies can be detected by electrical signals from the stickers. 

“Since it was an original study, the lie itself wasn’t complicated.” Professor Levy said that typically, when we lie, in real life we tell a longer narrative which contains both deceptive as truthful elements.

“In our research, we could hear the voices of the participants through their headsets. We also knew when they were lying. 

“Hence, we used advanced machine learning techniques to train our program so that it could identify lies using EMG (electromyography signals) signals emanating from the electrodes.

“Using this method we were able to achieve 73% accuracy – while not perfect but better than other technologies. 

“Another fascinating discovery is that different people lie using different facial muscles. Some lie with their cheek muscles, while others lie with their eyebrows.

According to the researchers, AI has ‘dramatic consequences in many spheres our lives’.

They predict that in the future AI-equipped cameras could be used at the airport, in an online job interview or in a police suspect interview to see if someone is fibbing

The future AI-equipped cameras will be used in online interviews, at airports and in police suspect interviews to check for fraud.

Professor Levy believes that electrodes could be replaced by video software, which can detect lies through facial muscles movements.   

He stated that high-resolution cameras, which are trained to detect facial movements and distinguish truth from lies, can be used in the workplace, the police station, the airport or online for job interviews.

“Right now our task is to finish the experimental stage and train our algorithms before we get rid of the electrodes. We expect the technology to be used in many other applications once it is perfected.

The journal Brain and Behaviour published the paper.  

In the past, critics have criticized artificial intelligence as a way to identify liars.

Manchester Metropolitan University, for example, suggested that AI could detect whether people lie at the border by analysing microgestures.

Ray Bull from the University of Derby’s criminal investigation department said, however, that the project is not credible because it does not show how microgeography can be used to detect lying.

He said, “They deceive themselves into believing it will ever prove to be substantial effective” and that they were wasting lots of money. 

“The technology was based upon a fundamental misunderstanding of how humans behave when truthful and deceptive.”

What are the NINE BEST WAYS to SPOT A LIAR

Big pause It is a difficult process that the brain and body must manage when lying. The truth is first produced by your brain, then suppressed before you can create the lie. 

This often leads to a longer pause than normal before answering, plus a verbal stalling technique like ‘Why do you ask that?’ rather than a direct and open response.

Eye dart: Humans have more eye expressions than any other animal and our eyes can give away if we’re trying to hide something. 

When we look up to our left to think we’re often accessing recalled memory, but when our eyes roll up to our right we can be thinking more creatively. A common eye contact cutting gesture is to look away, or downward, when someone feels guilty about a lying.

You have lost your breath Bending the truth causes an instant stress response in most people, meaning the fight or flight mechanisms are activated. 

As the mouth becomes dry and sweaty, your pulse rate increases and you breathe in shorter and shallower breaths. These can be seen and heard often.

Overcompensating: In an attempt to convince more people, a liar may overperform by gesticulating and speaking too loudly. This can lead to excessive eye contact, often without blinking! excessive emphasis on gesticulation.

The more someone gesticulates, the more likely it is they might be fibbing (stock image)

If someone gestures a lot, it’s more likely that they may be lying (stock image).

Poker face Although some people prefer to employ the poker face, many assume less is more and almost shut down in terms of movement and eye contact when they’re being economical with the truth.

The hide of the face: A person who tells lies often feels the urge to cover their face for their audience. It can cause a partial cut off gesture, such as the familiar nose touch and mouth-cover.

Self-comfort touches: Lies can cause stress and discomfort, so many people resort to using comfort gestures like rocking or hair-stroking. While we all use comfort gestures for our own self-comfort, this can be dramatically increased when someone lies.

Micro-gestures: These are very small gestures or facial expressions that can flash across the face so quickly they are difficult to see. Experts often slow down footage to see the real body language reaction. 

This is the best way to identify them in real-life. Look for facial expressions that occur after the liar finishes speaking. An instant tell-tale sign is a slightly skewed or rolly mouth.

Hands up! It is the feet or hands that are most challenging to work with. Liars can often have trouble keeping their mouths shut while lying. 

When the gestures and the words are at odds it’s called incongruent gesticulation and it’s often the hands or feet that are telling the truth.