In the fight-or-flight response, if a person is presented with a stressful situation (danger), a physiological response (sympathetic nervous system) activates the adrenal glands and cardiovascular system, allowing a person to adjust rapidly to the need to fight or flee a situation.

• Such physiological response is beneficial in the short term: for instance, in an emergency situation.
• However, with ongoing, chronic psychological stressors, a person continues to experience the same physiological response as if there were a real danger, which eventually physically and emotionally depletes the body.