"Like at work, if I need to tell someone that, for example, someone burned themselves on tea, I'd go to someone and continuously whip my hand out in a motion to build up to speak. Then I'd go, 'Paul ... Pauls ... Paul's ... Paul's burnt' with each wave. It can sound almost like a stutter, but if I'm not in close company, I'll do that to start speaking. It's like a kick-start to talk."
The neuroscience behind it has shown that it's partially auditory, as well overloading the emotional response part of your brain (the amygdala). Selective mutes generally listen, can't process how to deal with what they heard, and shut down the vocal reaction because the brain hits the panic switch. "The brakes suddenly go on everywhere, and then the gas pedal doesn't work."
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