Hyper-vigilance isn't a personality trait, it's a stress response first documented in combat veterans, and researchers later found the same scanning-for-danger reflex in children raised around unpredictable moods

Hypervigilance was first documented in 1941 by psychiatrist Abram Kardiner in combat veterans who could not stop scanning for threats. Researchers later found the same reflex in children raised around unpredictable parents. The pattern is a learned nervous system response, not a personality trait, and runs on the amygdala's threat-detection system.