Detecting Deception by Observing Hand-to-Face Touching
Self-touch Relieves Stress Caused by Lying
Posted December 3, 2015
By Steve Stoyanoff
Increased hand-to-face contact tends to signal deception. Hand-to-face contact increases with cognitive load and with the initiation of the fight or flight response. Liars often experience the fight or flight response and an increase in cognitive load, which causes stress. In order to accurately track increases in hand-to-face contact, a baseline must be established during times when the person being interviewed has no reason to lie. Any changes from the baseline may indicate deception.
Cognitive load reflects “The total amount of mental activity imposed on working memory in any one instant” (Malamed, 2015). Liars often experience cognitive overload because they must remember what they said or did not say, their nonverbal displays, and their verbal cues. Additionally, liars must monitor the lie target’s nonverbal displays and verbal cues to ensure the lie is believed. Too much information processed by the brain at one time leads to cognitive overload. In a study conducted at the University of Leipzig (Germany), researchers found that, “Touching changed electrical potentials in the brain, namely those having to do with storing information in working memory and emotional condition” (Jimenez, 2014). That discovery concluded touching the face reduces cognitive overload, which increases hand-to-face contact.
Fight or Flight Response
Liars experience the fight or flight response. The fight or flight response triggers a cascade of hormones from the sympathetic nervous system when humans feel threatened (Cannon, 1920). The fight or flight response increases heart rate, respiratory rate, blood sugar level, and adrenal hormones. In an effort to reduce the anxiety caused by lying, liars increase hand-to-face contact to deplete excess energy.
Liars often experience stress because they fear getting caught. Stress causes worry and anxiety. “We unconsciously touch our bodies when emotions run high to comfort, relieve, or release stress” (Givens, 2014). Pacifying gestures reduce stress. In an effort to reduce the stress which accompanies lying, liars tend to comfort themselves by increasing hand-to-face contact.
Laboratory Research Limitation
Some researchers found increased hand-to-face contact does not indicate deception. In experimental settings, study participants face no consequences for getting caught lying. Therefore, participants fail to experience stress. “Laboratory studies involve instructions to tell a low-stake lie about an action (study participants) recently performed. However, in the real world, lies are self-generated, often high risk and emotionally charged” (Wagner, 2010). In real-life settings, liars face consequences. In real-life settings liars experience cognitive overload. In real-life settings liars experience the fight or flight response. In real-life settings liars experience stress. Therefore, increased hand-to-face contact remains a good indicator of deception.
Hand-to-face contact increases with cognitive overload, the fight or flight response, and stress. Liars tend to increase hand-to-face touching due to experiencing cognitive overload, the fight or flight response, and stress. Therefore, increased hand-to-face contact is a good indicator deception.
The author of this post was a student in my Fall 2015 Police Report Writing class at Western Illinois University. He submitted the winning entry in the in-class, best-written end-of-semester paper competition. The blog post was edited for content and formatting.
Behavioral Psychology. (2015). Stress: Fight or Flight Response. Retrieved November 20, 2015, from http://www.psychologistworld.com/stress/fightflight.php.
Givens, D. (2014). Selftouch. Retrieved November 20, 2015, from http://center-for-nonverbal-studies.org/selftouc.htm.
Jimenez, F. (2014, December 28). Unmasking the mystery of why people touch their faces. Retrieved November 20, 2015, from http://www.worldcrunch.com/tech-science/unmasking-the-mystery-of-why-people-touch-their-faces/study-stimulation-behavior-brain-emotions/c4s17727/.
Malamed, C., McGinnis, J., & Buchler, M. (2015). What is cognitive load? Retrieved from http://theelearningcoach.com/learning/what-is-cognitive-load/.
Wagner, A. (2010). A judge’s guide to neuroscience: a concise introduction. Retrieved November 20, 2015, from http://memorylab.stanford.edu/Publications/papers/LawNeuroGuide.pdf.