We all need a built-in truth detector inside our brains that will help us find out in real-time when others are lying. It turns out that it can actually be done.
In a study published in the International Journal of Psychology & Behavior Analysis, scientists reveal a new, interesting way to expose liars in real-time. To understand how to do this, it is imperative to understand what happens to the brain when we lie.
What did scientists think until now?
Previous research on this fascinating subject has already shown that when we lie, it requires the brain to work harder, which increases energy consumption and temporarily impairs other cognitive abilities. In this study, a group of psychologists from the University of Portsmouth in England thought about how to use this insight to make it hard for liars.
The study
For the study, 164 people were recruited and asked their opinions on current hot-button issues in the UK such as how the government is handling COVID-19, leaving the EU i.e. Brexit and the functioning of now-former PM Boris Johnson. Then, the subjects were randomly divided into two groups: liars and truth-tellers.
In the second stage, the researchers, all certified psychologists, asked the participants their opinions on these explosive issues in order to identify the liars. To give participants an incentive to lie properly they promised to raffle off a cash prize to those who could outwit the polished investigators.
In addition, two-thirds of the respondents were also asked to memorize a license plate number and half of the people in this group were told that this number would be very important for further experimentation.
Driving makes us bad liars
The results of the study showed that people who were required to lie and also memorize the license plate number were much less good at this task compared to those who lied without any other worries on their minds.
Prof. Aldert Vrij, a social psychologist and lead study author explained: "This study shows that introducing secondary tasks for questioning can make it easier to identify lies but such tasks must be presented with care and sophistication.”
"This study shows that introducing secondary tasks for questioning can make it easier to identify lies but such tasks must be presented with care and sophistication.”
Prof. Aldert Vrij
What does this mean?
According to Vrij: "A secondary task will only be effective if the person lying doesn’t abandon it throughout the conversation. This can be done if the interviewees are told that this task is very important, or incorporate in the conversation another non-stop task such as grabbing heavy objects or driving a car.”
Also doing home repair work or tasks that require concentration will make it harder for people to lie and easier for you to catch them.
In this study, the respondents were psychologists and the exercise was more stressful than a normal conversation at home or at work, but its authors are convinced that these insights can be applied to the outside world. This is because lies require inventing stories and sticking to them over time.
"Truths and lies can sound equally plausible as long as speakers are given the opportunity to think carefully about what they are saying. When the ability to think in-depth diminishes, truths sound much more likely than lies,” Vrij added.