Hypervigilance narrows your attention into an incessant, on-guard scanning of the people around you. It also frequently projects you into the future, imagining danger in upcoming social events. Moreover, hypervigilance typically devolves into intense performance anxiety on every level of self-expression. Like the soldier overlong in combat, ptsd sets in because you feel as if you are constantly under attack. Unfortunately, internal attack is now added to external attack, and you become locked into hypervigilance and sympathetic nervous system arousal.