The parasympathetic nervous system (PSNS) is a division of the autonomic nervous system (ANS), along with the sympathetic nervous system (SNS) and enteric nervous system (ENS or "bowels NS"). The ANS is a subdivision of the peripheral nervous system (PNS). ANS sends fibers to three tissues: cardiac muscle, smooth muscle, or glandular tissue. This stimulation, sympathetic or parasympathetic, is to control smooth muscle contraction, regulate cardiac muscle, or stimulate or inhibit glandular secretion. The actions of the parasympathetic nervous system can be summarized as "rest and digest".he parasympathetic nerves (PSN) are visceral, autonomic branches of the peripheral nervous system (PNS). The autonomic nervous system (ANS), which includes sympathetic and parasympathetic divisions, regulates the body's visceral organs via the innervation of three kinds of tissues: smooth muscle, cardiac muscle, and glands. The sympathetic and parasympathetic system work in tandem to create a synergistic stimulation that is not merely on or off, but has been described as a continuum depending upon how vigorously each division is attempting to carry out its actions. The regions of the body associated with the parasympathetic division of the ANS are in the cranial and sacral regions of the spinal cord. Because of its location the parasympathetic system is commonly referred to as having craniosacral outflow whereas the sympathetic system is referred to as thoracolumbar outflow (T1-L2 spinal nerves). In the cranium the PSN originate from cranial nerves CN III (oculomotor nerve), CN VII (facial nerve), CN IX (glossopharyngeal nerve) and CN X (vagus n.) In the sacral region of the body the PSN is derived from spinal nerves S2, S3 and S4, commonly referred to as the pelvic splanchnics.
Parasympathetic Nervous System Innervations
The parasympathetic nervous system (PSNS) is a division of the autonomic nervous system (ANS), along with the sympathetic nervous system (SNS) and enteric nervous system (ENS or "bowels NS"). The ANS is a subdivision of the peripheral nervous system (PNS). ANS sends fibers to three tissues: cardiac muscle, smooth muscle, or glandular tissue. This stimulation, sympathetic or parasympathetic, is to control smooth muscle contraction, regulate cardiac muscle, or stimulate or inhibit glandular secretion. The actions of the parasympathetic nervous system can be summarized as "rest and digest".he parasympathetic nerves (PSN) are visceral, autonomic branches of the peripheral nervous system (PNS). The autonomic nervous system (ANS), which includes sympathetic and parasympathetic divisions, regulates the body's visceral organs via the innervation of three kinds of tissues: smooth muscle, cardiac muscle, and glands. The sympathetic and parasympathetic system work in tandem to create a synergistic stimulation that is not merely on or off, but has been described as a continuum depending upon how vigorously each division is attempting to carry out its actions. The regions of the body associated with the parasympathetic division of the ANS are in the cranial and sacral regions of the spinal cord. Because of its location the parasympathetic system is commonly referred to as having craniosacral outflow whereas the sympathetic system is referred to as thoracolumbar outflow (T1-L2 spinal nerves). In the cranium the PSN originate from cranial nerves CN III (oculomotor nerve), CN VII (facial nerve), CN IX (glossopharyngeal nerve) and CN X (vagus n.) In the sacral region of the body the PSN is derived from spinal nerves S2, S3 and S4, commonly referred to as the pelvic splanchnics.
