Another word for hypervigilance is hyperarousal, where you are over-reactive to any possible danger in the environment. When you are hypervigilant, you are constantly on-guard for any possible threats, and you are easily startled by any sudden noises. When you have hypervigilance, you are at a heightened level of sensory sensitivity, relentlessly scanning your environment for threats, and the fear and anxiety that accompanies hypervigilance can lead to physical and mental exhaustion.
Hypervigilance is a symptom of anxiety disorders such as post traumatic stress disorder (PTSD).
