Which part of the nervous system controls the body’s fight-or-flight response?

The sympathetic nervous system is responsible for controlling the body’s fight-or-flight response. This system activates the body's accelerated reaction to stressful situations. When faced with a perceived threat, the sympathetic nervous system triggers a series of physiological changes: heart rate increases, blood vessels constrict, and energy supplies are mobilized. These responses prepare the body to either confront or flee from danger, ensuring survival.

In contrast, the parasympathetic nervous system works to promote a state of calm and relaxation after a stressor has passed. It helps slow the heart rate and initiate restorative processes. The somatic nervous system is primarily involved in voluntary muscle control and sensory information processing but does not play a direct role in automatic stress responses. The central nervous system, which includes the brain and spinal cord, processes information and coordinates activity, but it does not directly manage the fight-or-flight reactions, as that is specifically the domain of the sympathetic nervous system. Thus, the sympathetic nervous system is crucial to understanding how our bodies react in high-stress situations.