What is the typical function of the sympathetic nervous system?

The sympathetic nervous system is primarily responsible for initiating the fight or flight response, a physiological reaction that occurs in response to a perceived threat or stressor. When activated, the sympathetic nervous system prepares the body to either confront or flee from danger. This response includes increasing heart rate, dilating airways, and redirecting blood flow to essential muscles while inhibiting functions that are not immediately necessary for survival, such as digestion.

This activation is crucial in situations where rapid reactions are necessary for survival and situates the body in a state of heightened alertness. Understanding this function is fundamental for recognizing how the body's autonomic responses affect behavior and physiological states during stressful situations.