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Sympathetic Nervous System

The sympathetic nervous system is one of the two main divisions of the autonomic nervous system, which controls involuntary bodily functions. It is often referred to as the "fight or flight" system because it prepares the body to respond to stress or danger. When activated, the sympathetic nervous system increases heart rate, constricts blood vessels, dilates the airways in the lungs, and diverts blood flow to essential organs like the brain and muscles. These physiological changes help mobilize the body's resources to deal with perceived threats. After the stressor is resolved, the parasympathetic nervous system, the other division of the autonomic nervous system, works to bring the body back to a state of rest and relaxation.