What is the primary function of the parasympathetic nervous system?

1 Answer
Jun 2, 2017

The parasympathetic nervous system (PSNS) is responsible for the stimulation of "rest and digest" or "feed and breed" activities that occur when the body is at rest.


The PSNS regulates organ and gland functions during rest and is considered a slowly activated dampening system. Body functions stimulated by the PSNS include salivation, lacrimation, sexual arousal, urination, digestion, and defecation.

The PSNS acts in concert with the sympathetic nervous system and conserves the body's energy by bringing bodily functions back to homeostasis, particularly after the fight or flight response is activated by the sympathetic nervous system,

The PSNS is revered to as the "feed and breed" system because it regulates more mundane processes that are vital for the maintainance of normal life. Without the PSNS the monitoring and regulation of everyday body processes would be impossible. It helps in maintaining the mental and physical health by helping the body to calm down from stress reactions that elevate blood pressure, dilate the pupils and divert energy from other body processes to fighting or fleeing.

The PSNS is one of the three main divisions of the autonomic nervous system.