What is the role of the sympathetic nervous system during stress?

The sympathetic nervous system plays a crucial role in the body's response to stress by activating the fight-or-flight response. When a person perceives a threatening situation, the sympathetic nervous system triggers a series of physiological changes to prepare the body for action. This includes an increase in heart rate, rapid breathing, and a surge of adrenaline, which heightens alertness and energy levels. The activation of this system is vital for survival, allowing individuals to either confront a threat head-on or escape from it.

In contrast, calming the body and promoting relaxation is the function of the parasympathetic nervous system, which is not active during stressful situations. Regulating digestion and conserving energy are also functions primarily associated with the parasympathetic system, which helps the body relax and restore itself after a stressful encounter. While the response to stress can indeed enhance cognitive function to some extent—by improving focus and attention—the primary response during stress is the mobilization of energy and resources for immediate physical action through the sympathetic nervous system. Thus, the activation of the fight-or-flight response is key to understanding how the body reacts to stress.