Excellent! many of the psychological facts that you describe are part of what we call communicatively: body language. I would like to recommend "the language of Allan Pease's body".
With respect to the chewing gum recommendation, it is so true that Sir Alex Ferguson, former technical director of the English football team, Manchester United, was medically recommended to chew gum to manage stress after he was hospitalized for tachycardia and was branded with a step marker.
Thank you for such an interesting post friend @jwolf. Greetings.
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