What physiological responses are associated with increased hypervigilance?

Heightened responsiveness to stimuli is a physiological response that accompanies increased hypervigilance. When an individual is hypervigilant, their body is in a heightened state of alertness, which can be attributed to the activation of the sympathetic nervous system. This state is designed to prepare the body to respond to potential threats, leading to increased sensory perception and a faster reaction time to environmental changes or potential dangers.

During hypervigilance, an individual may experience heightened awareness of their surroundings, increased heart rate, rapid breathing, and muscle tension, all of which are part of the body's fight-or-flight response. These physiological changes aid in improving responsiveness to stimuli, making it easier to detect and react to any threats or unusual situations.

In contrast, the other options represent states that would typically be characterized by a lower level of alertness or concern. For instance, decreased aggression, relaxed demeanor, and an unconcerned attitude reflect a more subdued physiological state that is the opposite of hypervigilance.