Wiktionary
n. (context neuroanatomy English) One of the divisions of the autonomic nervous system, based between the brain and the spinal cord, that slows the heart and relaxes muscles.
WordNet
n. originates in the brain stem and lower part of the spinal cord; opposes physiological effects of the sympathetic nervous system: stimulates digestive secretions; slows the heart; constricts the pupils; dilates blood vessels [syn: parasympathetic]
Wikipedia
The parasympathetic nervous system (usually abbreviated PSNS, not PNS, to avoid confusion with the peripheral nervous system [PNS]) is one of the two divisions of the autonomic nervous system, the other being the sympathetic nervous system. The autonomic nervous system is responsible for regulating the body's unconscious actions. 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. Its action is described as being complementary to that of the sympathetic nervous system, which is responsible for stimulating activities associated with the fight-or-flight response.
Nerve fibres of the parasympathetic nervous system arise from the central nervous system. Specific nerves include several cranial nerves, specifically the oculomotor nerve, facial nerve, glossopharyngeal nerve, and vagus nerve. Three spinal nerves in the sacrum (S2-4) also act as parasympathetic nerves. These are commonly referred to as the pelvic splanchnic nerves.
Because of its location, the parasympathetic system is commonly referred to as having "craniosacral outflow", which stands in contrast to the sympathetic nervous system, which is said to have "thoracolumbar outflow".
Usage examples of "parasympathetic nervous system".
Chris noted that Henry Noble's symptoms were more muscarinic than anything else, meaning the kind that were expected when parts of the parasympathetic nervous system were stimulated.
So Sax ran a forefinger up and down the bridge of his new nose, and drank the wine which did indeed suppress his parasympathetic nervous system to the point of making him less inhibited and more voluble, and he chattered away very successfully, he thought, although several times he was alarmed by the way he was drawn into conversation by Phyllis, sitting across the table from him-and by the way she looked at him-and by the way he looked back!
When they passed, the parasympathetic nervous system, the part that was in charge during sleep and ran all the automatic systems, came back with a vengeance.