There’s another reason we tend to put our faith in people who project passion, confidence, and enthusiasm: these traits can’t easily be faked. When we’re feeling brave and confident, our vocal pitch and amplitude are significantly more varied, allowing us to sound expressive and relaxed. When we fearfully hold back — activating the sympathetic nervous system’s fight-or-flight response — our vocal cords and diaphragms constrict, strangling our genuine enthusiasm.10
