Parasympathetic division

Parasympathetic division:
• sometimes called the craniosacral division (arises from the brain and sacral region of spinal cord); soma of preganglionic neurons are in pons, medulla oblongata and in S2-S4 of spinal cord; ganglia re near or in target organs; usually 2 post ganglionic neurons for each preganglionic neurons; leave brainstem by four cranial nerves (oculomotor, facial, glossopharyngeal, vagus) and by forming the pelvic splanchnic nerves
• preganglionic neurons are considerably longer than postganglionic neurons
• more active in non-stressful situations – “resting and digesting”/”housekeeping” functions
• functions to conserve body energy; maintains body functions at basal levels
• stimulation of appropriate parasympathetic pathways results in decreased heart rate and force of contraction, increased gastric secretion, bladder and bowel emptying, focusing the eye from near vision, constriction of the pupil, contraction of the bronchial smooth muscle

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