How to Detect a Liar

Dr. Greggory House
(House MD) (2)

Deception is deliberately saying something that you know is untrue to someone with the intention of deceiving them. In other words, deception is another way of saying you lied to them. Everyone lies. In fact, people tell about ten lies per week on average (1).  Despite knowing this, no one wants to be lied to. In fact, we would like to think that we are accurate in detecting when someone is lying to us. Unfortunately, the people who often utilize lying the most are also those who are very concerned about creating positive self-presentations and therefore are more sociable and manipulative (1). On top of that, an average person’s ability to detect lying is no greater than chance. Yes, that’s right. You are only 50% likely to catch if someone is lying to your face.This statistic causes society many problems. Obviously we want our ability to be greater than chance when it comes to detecting a liar not only for personal reasons, but certainly for catching criminals that could get away with murder. Luckily, research is making progress on more effective methods for detecting lies. Many studies have looked at various nonverbal communication cues and even brain imaging in order to further this field.

     An interesting study conducted at the University of Pennsylvania investigated the possibility of using fMRIs in order to detect deception. (3) The study was only conducted with one participant, JG (a male newspaper reporter), who was told to pretend he was applying for a job as a science writer. After the main experimenter told him the job requirements, JG had his resume returned to him for revising. He was told to “employ whatever means necessary to be hired” and to return the resume. It is important to note that all the other research members were unaware of this exchange. JG was not specifically told to lie about any part of his resume at any point. Later, JG was instructed that he was going to be tested using the fMRI and to answer all questions about his resume as truthfully as possible. He was asked three known truths (to the experimenter) and three unknown statements fifteen times in a pseudorandom order. After being debriefed, JG reported that he had told the truth on the three truth statements but lied on the unknown ones. Looking at the results, lies in two of the three “unknown” items were associated with an increase in prefronto-parietal activation, and could therefore be categorized as a lie. This supported the thought that the inferior parietal/frontal regions are highly associated with deception. The third unknown, which happened to be “did you serve in the military” did not activate these regions at all. Interestingly, the hippocampus and amygdala were activated instead. The researches hypothesized that this change may be a result of the question itself (in which JG had particular feelings about the military that evoked this change), or because of the question’s social inappropriateness and moral dilemma. This finding, however, could be used for further study of lying about personally or socially significant questions.


     Naturally, this study cannot be generalized by any means. There was only one participant and they were simply clinical trials to see what work could be done using fMRIs for the field of deception. Though there were no definite findings, I found it very interesting to consider the possibility of using brain imaging technology to measure truthful statements. As most people know, the technology we currently use for lie detection is the polygraph. Unfortunately, it is not a very reliable source of information because it measures ANS arousal rather than something like cognition. If researchers could really utilize brain imaging in a way to measure activity when lying, it would completely revolutionize the field. If nothing else, a decent brain imaging technology could at least serve as a way to verify decisions made based on nonverbal communication. The machinery required would be insanely expensive, immobile and raises questions of ethics, however. There is still much needed research for technique of lie detection before any changes are to come.


     Using expensive machines however, is not the only way to detect lies.  There are many clues we can look for to help reveal deception.  Nonverbal cues are very helpful in detecting a liar, because we are not aware of the nonverbal things that we do.  Such as the pitch of our voice can get higher when we lie (4).



With as much overlap and
variability as these kind of
statistics give rise to, its no
wonder we do not completely
rely on such cues (5).

      Although nonverbal cues are one of the best ways to identify a lie, even they have many weaknesses. Nonverbal cues are not giveaway clues into the truth.  For example, the saying “the eyes are a gateway into the soul” might imply that we can always tell a lie when we look into somebody's eyes.  This is not true, however.  Since this is a very known belief, in this circumstance, if somebody is lying, they may make sure they keep direct eye contact.  Therefore, this would not be an accurate way to figure out a liar.  Nonverbal cues merely represent what is more likely to happen when someone is telling the truth vs. telling a lie. Many nonverbal cues have been found are based on small statistical patterns and cannot guarantee a persons deception (5). For instance, the nonverbal cue of greater number of blinks during a lie is a statistically significant finding that should not go unaccounted for. However, one cannot simply identify a lie every time someone blinks more than usual.

     One of the greatest strengths of nonverbal cues of lying is that they are mostly based off uncontrollable expressions fueled by uncontrollable expressions fueled by emotions. This makes them very difficult to suppress, which is why we are very tempted to rely and trust these cues. Unfortunately for people who are exceptionally great at reading these cues, “human lie detectors,” even emotions can be misleading, making no cue a clue to a lie. Have you ever been scared when telling the truth? Being questioned, especially during high stakes situations, can be very stressful (5). Despite our best effort, our faces leak out microexpressions: facial expressions that last for less than ¼ of a second that portray that persons true emotion. It’s said that liars often display microexpressions of fear during the act, but what about an extremely nervous truth teller? In the question lies the answer. Even mircoexpressions can be misleading.

       So, if the physiological responses, and the nonverbal cues are never perfectly accurate, then can we ever tell if somebody is lying?  Really, we can't.  But, there are definitely circumstances where we have a pretty good idea that somebody is lying.  For example, it can be much easier to tell if somebody is lying if they are close to you.  When somebody you love is deceiving you, there may be ways to figure it out easier than if a stranger were lying to you.  This can be for multiple reasons:  If you are very close to someone, you may be able to tell when they are acting differently.  Or more specifically, if somebody you know very well is trying to lie to you, you may realize the lie, because you know details about them and the story may not go along with what you know about them (4). For example, just the other day one of my friends called me to complain about one of his friends.  He invited her to come to a wedding reception with him, and she agreed.  Then the day of, she told him she was asked to work two extra hours at work.  Since my friend knows her very well, he knew this story seemed extremely inconsistent with her behavior, and with her job.  He knew that she would not usually work extra hours to when asked, especially if she had other plans.  Therefore, this made him to believe she was lying about the whole thing, and secretly had other plans, and this made him extremely angry. 

     Another example would be a scene from the movie Just Married. Though we could not embed the video into this blog entry, if you go to http://www.dailymotion.com/video/xhqz73_a-pig-with-hair_shortfilms, you will see a clip from the movie that displays how there are many ways to tell if a loved one is lying. In the clip, Ashton Kutcher's character, Tom is trying to lie to Brittany Murphy's character, Sarah.  But, she can tell he is lying because of the way his face involuntarily moves.  She also realizes that his story is not consistent with the usual behavior of her dog.  Once again, as with all other ways of detecting a lie, this method does not always work either.  This is because we do not want to believe that somebody we love may be lying to us, so we remain blind to the clues and just decide to buy their lies in order to protect ourselves.


     Deception is just something we unfortunately, have to learn to live with.  No machines, nonverbal cues, or closeness to a person can clearly or accurately point out a lie.  Humans have just really seemed to perfect the art of deception.

    

REFERENCES: 

1. Franzoi, Stephen L. (2009). Social Psychology. New York: McGraw-Hill. 122-123.

2. Dr. Greggory House photo from http://foxshop.seenon.com/detail.php?p=70778

3. Hakun, J.G., Ruparel, K.K., Seelig, D.D., Busch, E. E., Loughead, J. W., Gur, R. C., & Langleben, D. D. (2009). Towards clinical trials of lie detection with fMRI. Social Neuroscience, 4(6), 518-527. doi:10.1080/17470910802188370

4. Svetieva, E.  (2011).  Deception [Power point presentation]. Retreived from https://ublearns.buffalo.edu/webapps/portal/frameset.jsp?tab_group=courses&url=%2Fwebapps%2Fblackboard%2Fexecute%2Fcontent%2Ffile%3Fcmd%3Dview%26content_id%3D_1812400_1%26course_id%3D_89404_1%26framesetWrapped%3Dtrue

5. (2001). Nonverbal signs of lying.  Truth about deception. Reference from http://www.truthaboutdeception.com/lying-and-deception/detecting-deception/nonverbal-cues.html