By Aryaman Bhatia, Science and Tech editor, The Pawprint
Prof Yael Hanein places electrodes on the left side of my face.
“Move your eyes, blink, smile, and then try to relax,” she instructs. “We’ll find out soon if you’re a good or lousy liar.”
Prof Hanein and colleague Prof Dino Levy lead a team at Tel Aviv University in Israel that has developed a novel way of lie detection.
They claim to have found two sorts of liars: those who move their brows automatically when telling a lie, and those who can’t control a very little lip movement where their lips meet their cheeks.
Their software and algorithm can presently detect 73% of falsehoods, and they want to increase this as the system evolves. “One of the things you strive to avoid when you’re trying to conceal a lie is any kind of physical reaction,” she explains.
“But it’s very, very difficult to disguise a falsehood with this technology,” Prof Levy says.
Methods of detecting lies have most likely existed for as long as tall stories have been told. One of the first reported occurrences dates back to 1000BC in China when a suspect was required to fill his or her mouth with dry rice.
After a certain amount of time, the grains were tested, and if they remained dry, the accused was found to be guilty. The notion was that if the person had lied, he or she would feel afraid or worried, and so have a dry mouth.
The earliest lie-detecting devices, or polygraphs, were invented in the early twentieth century. The most well-known is the “analog polygraph,” which uses three or four ink-filled needles that dance around on a strip of moving paper.
Sensors are attached to the suspect’s fingertips, arms, and body, and the system analyzes their breathing rate, pulse, blood pressure, and sweat as they answer a series of questions.
Nonetheless, there are ongoing worries regarding the accuracy of these devices and if they may be fooled. As a result, academics and technology companies all over the world are attempting to create more high-tech polygraph equipment.
Dr. Sebastian Speer and his colleagues at Erasmus University in Rotterdam, Netherlands, are utilizing MRI (magnetic resonance imaging) equipment to detect if someone is lying or cheating. This is accomplished by examining color changes in brain scans in response to inquiries.
“Essentially, we find different parts of the brain that are more strongly stimulated lit up on scans whether someone decides to cheat or be honest,” explains Dr. Speer.
EyeDetect, a high-tech lie detection technology developed by the Utah-based corporation Converus, is already in operation. This focuses on involuntary eye movements as a means of detecting falsehoods.
A subject is asked a series of true or false, or yes or no questions. While they do so, eye tracking software monitors and analyzes their replies. The result is then delivered in five minutes and promises to be 86-88 percent accurate.
Former CIA officer Christopher Burgess warns that lie detectors should not be viewed as the end-all and be-all for confirming the guilt or innocence of criminals – or spies.
“It’s one of the tools employed throughout an investigation’s questioning phase,” he explains. “Evidence is how liars, scoundrels, frauds, and forgers are exposed.”
Mr. Burgess, who is now a security analyst, adds that the devices are not 100% accurate, and that he was wrongfully accused by a false test result in the mid-1990s.
He claims that as more high-tech lie detecting devices are used, “ethical and moral concerns” persist.
Back at Tel Aviv University, the researchers believe that video cameras and software capable of detecting a liar from a distance or even over an internet link will ultimately replace the electrodes.