Nonverbals and Deception

Humans have a love and hate relationship with lying. On one hand, we hate to be lied to, but on the other hand, we participate in deceptive actions all the time. Regardless of whether or not lying is morally acceptable, it is beneficial to familiarize one’s self with some of the more subtle nuances of deception.

A common misconception of detecting deception is that one can more accurately identify a liar by observing nonverbal behavior. This is an easy connection to make. Think about yourself when you tell a lie. A liar is usually always aware of the fact that they are telling a lie, and that has implications on the liar’s level of physiological arousal. The reason for this is because lying takes more mental effort than telling the truth because the liar has to keep straight two stories in his or her mind, the truth and their version of the truth. This is when the correlates of deception show up in nonverbal behavior. The liar will typically offer shorter responses than a “truther” would, will fidget more, make more errors in their speech, blink more, and so on. The four correlates I just exemplified are some of the most common correlates of deception, but there are others in existence.

So why is it hard to identify liars based only off of their nonverbal behavior? A leakage cue refers to an instance when someone lets his or her true emotion “leak” through when telling a lie. Examples of leakage cues could be fidgeting, blinking, or any other correlate of deception. The problem in detecting deception comes because these leakage cues are so short in duration. Often times, the leaked displays of emotion only last a fraction of a second, so a human cannot accurately detect the deception. This makes sense too. The person charged with detecting the deception has other things to do in the interaction besides blow the cover of their lying interlocutor. Simply listening to the other person is enough of a distraction to lose focus of their leakage cues. It is not impossible to tell is someone is lying to you, but if you are to judge that person based only off of nonverbal cues, you are likely to not get far.