When evaluating for possible deception there are a multitude of characteristics - nonverbal, verbal and paralanguage which are often overlooked - and indeed relatively rarely known. While not alone in these qualities, particularly among politicians, Donald Trump displaces many of these on a regular basis. The following are four common characteristics of possible deception which are scarcely discussed.
1. Low Verbal Variation: Donald Trump, in his public appearances - both political and in settings from years past, has used and continues to use a vocabulary equivalent to that of a 3rd or 4th grader. This has been measured by linguists using widely accepted algorithms. Such limited vocabulary enables a person to lie easier. When you don't have think as hard (or speak in depth) - it enables more "brain power" for lying.
2. Low Nonverbal Variation: Mr. Trump's body language is very similar to his verbal vocabulary - in that it has a limited in variety of expression. A good fraction of Mr. Trump's face and body movements chronically exhibit what amounts to "nonverbal monotone". His hands, arms, face, etc. default to his limited cliché body language repertoire. Thus when he does tell a lie, it is relatively easy (compared to most other people) to force himself into an autonomous nonverbal behavioral subroutine - much like an athlete who has good form despite being tired or stressed (sometimes colloquially referred to as "muscle memory"). Unlike the athlete however, this somewhat analogous physical behavior is used to deceive rather than to win at a sporting event.
3. Hyperbolic Nonverbals: Some who read this may know of the phenomenon where a person may "put on" a behavioral neutral "mask" - or "stone face" or "poker face" in the midst of a deception (or for a longer period such as in a courtroom/trial). This is one behavioral signal of possible deception. Yet the opposite is also true - those who always/often/contextually display extreme nonverbal behaviors - which, when compared to the vast majority of others in similar situations - are significantly out of proportion to the social context - are also often lying.
Call into your memory a classroom theatrical production from 7th grade. Remember those grandiose facial expressions and dramatic hand/arm/body language displays? These are very commonplace and even somewhat encouraged because of the physical distance the actors are typically from an audience. Mr. Trump chronically displays similar dramatic nonverbal signals. These extreme amplitudes of body language behavior also cloak deception. An analogy would be using a lot sweet "chaser" after (or before or during) the taking of bitter medicine. The extreme body language covers up the deceptive tells that would otherwise be visible - allowing the liar to dilute his poison.
4. Paralanguage Variation: Much like low variability of the spoken word language as well as body language, paralanguage which is monotonous may also be suspect - especially when it's extreme. Mr. Trump often talks louder and even shouts when most people in similar contexts would speak with considerably lower volume. Many have pointed out his "tone-of-voice" and his tendency to project negative qualities with it (arrogance, impatience, condescending emotions, etc.). While a nuance behavior to some (and perhaps even [erroneously] perceived to be nonexistent by others) - it's very possible to project strength without anger - and empathy without weakness. Chronically higher volume and angry tones (and other vocal qualities) - when out of context - are also signals of deception and ulterior motives.
It's important to stress that these are by no means the only signals of possible deception - they are however rarely recognized. Take heed.
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