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The Wisdom of Psychopaths
In this engrossing journey into the lives of psychopaths and their infamously crafty behaviors, the renowned psychologist Kevin Dutton reveals that there is a...
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We may think we know the telltale signs of lying, be it shifty eyes or nervous fidgeting. Professional interrogators look for such tells, too, assuming a suspect’s nervousness betrays his guilt. But interrogation can rattle even the innocent, so nervousness alone cannot distinguish liars from truth-tellers.
Scientists looking for better ways to detect lies have found a promising one: increasing suspects’ “cognitive load.” For a host of reasons, their theory goes, lying is more mentally taxing than telling the truth. Performing an extra task while lying or telling the truth should therefore affect the liars more.
To test this idea, deception researchers led by psychologist Aldert Vrij of the University of Portsmouth in England asked one group to lie convincingly and another group to tell the truth about a staged theft scenario that only the truth-tellers had experienced. A second pair of groups had to do the same but with a crucial twist: both the liars and the truth-tellers had to maintain eye contact while telling their stories.
Later, as researchers watched videotapes of the suspects’ accounts, they tallied verbal signs of cognitive load (such as fewer spatial details in the suspects’ stories) and nonverbal ones (such as fewer eyeblinks). The eyeblinks are particularly interesting because whereas rapid blinking suggests nervousness, fewer blinks are a sign of cognitive load, Vrij explains—and contrary to what police are taught, liars tend to blink less. Although the effect was subtle, the instruction to maintain eye contact did magnify the differences between the truth-tellers and the liars.
So do these differences actually make it easier for others to distinguish liars from truth-tellers? They do—but although students watching the videos had an easier time spotting a liar in
the eye-contact condition, their accuracy rates were still poor. Any group differences between liars and truth-tellers were dwarfed by differences between individual participants. (For example, some people blink far less than others whether or not they are lying—and some are simply better able to carry a higher cognitive load.)
All this makes it hard to put the study’s findings into practice—especially out in the field, where the people most likely to lie are those who are good at lying. “In the real world, there’s no Pinocchio-like cue that distinguishes liars from truth-tellers,” says study co-author Ronald Fisher of Florida International University. Magnifying subtle differences may be the next best thing. [For more on lie detection, see “Portrait of a Lie,” by Matthias Gamer; Scientific American Mind, February/March 2009.]
Note: This article was originally printed with the title, "The Load of Lying."
This article was originally published with the title The Load of Lying.
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8 Comments
Add CommentActually police ARE taught that liars deliberately try to blink less. Lying is a strategy that we all know how to use. If it becomes the preferred strategy, it's partly because the liar had reason to be better at it than otherwise. A confident liar may well show less anxiety than the relatively defenseless truth teller.
Reply | Report Abuse | Link to thisThe general public guesses correctly about 41% of the time. FBI and CIA are about chance (50%) Only the Secret Service scores above chance.
Reply | Report Abuse | Link to thisTheir being quite like Pinocchio:
Reply | Report Abuse | Link to thispretty much still works.
I'm a retired Federal investigator. I don't know what those statistics are supposed to be based on, but if you include the use of professional interviewing techniques, they are way off.
Reply | Report Abuse | Link to thisWhat if you deliberately increase the person's cognitive load during questioning? For instance, give them a task to do while they're being questioned that requires them to think. In theory, telling the truth should take little to no effort and the unrelated cognitive task could be done simultaneously while the lie would require more attention, possibly slowing their progress in the task or pausing it entirely to address the lie.
Reply | Report Abuse | Link to thisThis might not work in all cases, but I think it would at least be an interesting thing to do a study on.
The truth as you have retained it in your memory is multi-dimensional with diminishing degrees of significance. The lie is manufactured to attempt to "replace" part of that memory. Good liars can do that better than bad ones. None can do it well enough to make all the dimensions fit. Proper interrogation can soon expose the inevitable inconsistencies.
Reply | Report Abuse | Link to thisWhich is a lot easier than getting the confession, but that's a subject for another time.
Candide,
Reply | Report Abuse | Link to thisYour post has no value or supporting arguments. What do you base your criticism on? Any ignorant idiot can use sarcasm to express a negative reaction. Try acting like you have a brain and give a reason why you don't like the article.
Based on the actual FACTS in some of the other posts, this article does have flaws. The other posters were mature and intellegent enough to post why the article was flawed. Your post reminds me of middle school kids trying to be clever.
To feed you back your own attitude: If you don't like the article, click on something else.
This is completely invalid, totally failing to take into account common conditions such as aspergers syndrome or autism spectrum disorders, or cultural effects on eye contact. Many cultures have very different rules regarding eye contact and situations of forced eye contact as described here would be impossible to achieve without abnormally high levels of stress.
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