The parasympathetic nervous system (PSNS) is one of the two divisions of the autonomic nervous system (a division of the peripheral nervous system (PNS)), the other being the sympathetic nervous system. The parasympathetic system is responsible for stimulation of "rest-and-digest" or "feed and breed" activities that occur when the body is at rest, especially after eating, including sexual arousal, salivation, lacrimation (tears), urination, digestion and defecation. (https://en.wikipedia.org/wiki/Parasympathetic_nervous_system)