Human Lie Detectors


While reading about lying and lie detection in the book I was particularly interested by the section "Humans as Lie Detectors." It mentioned that people generally have a 55% chance of detecting that someone has told a lie. It also mentions that certain groups we may expect to have a higher chance of detecting a lie, actually perform at levels similar to most people.


I have personally watched almost every episode of "Lie to Me" that was made, before it was cancelled in 2011. In one the episodes Cal Lightman, of The Lightman Group which the show is about, meets one of his future employees . This character is working as airport security, which you could argue is similar to a customs official at an airport, which is one of the groups specifically named in the book as being expected to perform better in detecting lies, but is actually just about as accurate as most people.

In the show she is portrayed as a natural at detecting lies. While this opposes the what the book says in generally the case, it got me thinking about what makes a person better at detecting lies than any other person. The book mentions certain groups, such as secret service agents, clinical psychologists and some judges or law enforcement officials as being more adept at detecting lies. It also suggests that their superior lie detection is attributed to year of experience in spotting lie, but how do they even detect lies?

Lie to Me Cal.jpg

The book mentions types of machine that can help determine if a person is being deceptive, but it doesn't mention how to spot lies without machinery, which is essentially what the show "Lie to Me" is about. The show heavily used the idea of "Micro Expressions," which is a major part of Ekman's work. The premise of these micro expressions is that if you can detect the micro expression, which is essentially a brief show of emotion on a person's face, you can use that to determine if the person is lying. These expressions, which are shown even when a person is attempting to conceal their emotions, are 1/15 to 1/25 of a second. These expressions merely tell you an emotion is being hidden, but not why. Which can be a similar problem with other forms of lie detection.

Micro Expressions.jpg

Do you think this method will ever be used to detect deception in criminals the way modern lie detection equipment is used?



You did a great job with connecting the show to our text. I do believe that law enforcement should start using these micro expressions to detect lies. But, on the other hand, how are we going to do this? By possibly setting up a camera in front of the suspects face during questioning? if it happens for 1/25 of a second, will we be able to detect it efficiently enough? Its a great topic to ponder. Good job on the post.

I had never heard of this show before your post, but it sounds very interesting! I think that this lie detection method would be helpful, but that it couldn't stand alone as the sole evidence that someone lied in a court situation or somewhere similar. I think that a lot of people would doubt the validity of evidence that relies on just a liar's body beyraying them, but that in split-second decisions that airport security officers make, it could be a useful tool. The measurements are so rudimentary and vague at the moment that I think security officials would be wary of relying on them in critical, high-stress environments like questioning a terrorist. However, it's definitely interesting stuff that I hope they'll keep using on the side to make airport security better!

I thought it was cool that you were able to connect the things we are learning about in our book to entertainment. I think that there are only a few options available today that are able to measure such quick movements. One option is to video tape the interview by using high-speed cameras or the other option would be to use sensors to record muscle contractions that happen in such a short time. Training people to notice such short muscle movements in the face would be very hard to do as and a person might possibly miss these giveaways simply by blinking. overall i think that the government needs to look into more efficient ways of lie detection and nice job on the post!

Good job in writing such an interesting blog! I really enjoyed how you connected the show to what we learned in class. To some extent I believe that some people are more adept at detecting lies than others through years of experience. Although the study shows that most people generally perform at similar levels with 55% chance of detecting lies, I don't think I belon in the majority because I am terrible at detecting lies. It is fascinating to see how certain emotions produce certain facial expressions and body movements as you showed in the illustrations. I am now very curious about the "micro expressions" and really want to be able to detect such expression myself.

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This page contains a single entry by jaco1506 published on April 1, 2012 10:22 PM.

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