Search results
Results from the WOW.Com Content Network
The sympathetic division typically functions in actions requiring quick responses. The parasympathetic division functions with actions that do not require immediate reaction. A mnemonic to summarize the functions of the parasympathetic nervous system is SSLUDD (sexual arousal, salivation, lacrimation, urination, digestion and defecation).
Cranial nerves are the nerves that emerge directly from the brain (including the brainstem), of which there are conventionally considered twelve pairs. Cranial nerves relay information between the brain and parts of the body, primarily to and from regions of the head and neck , including the special senses of vision , taste , smell , and hearing .
Parasympathetic innervation of the heart is partially controlled by the vagus nerve and is shared by the thoracic ganglia. Vagal and spinal ganglionic nerves mediate the lowering of the heart rate. The right vagus branch innervates the sinoatrial node. In healthy people, parasympathetic tone from these sources is well-matched to sympathetic tone.
The sympathetic nervous system is described as being antagonistic to the parasympathetic nervous system. The latter stimulates the body to "feed and breed" and to (then) "rest-and-digest". The SNS has a major role in various physiological processes such as blood glucose levels, body temperature, cardiac output, and immune system function.
Cranial and sacral spinal fibers are parasympathetic GVE fibers, while thoracic and lumbar spinal cord give rise to sympathetic GVE fibers. [4] The cranial nerves containing GVE fibers include the oculomotor nerve (CN III), the facial nerve (CN VII), the glossopharyngeal nerve (CN IX) and the vagus nerve (CN X). [5]
The division of the autonomic nervous system into sympathetic and parasympathetic pathways is particularly useful from a medical treatment perspective [source]. Jänig et al. warn that changing the classifications of the systems could result in confusion on how to treat some disease, particularly those of the gut and stomach region. [9]
Sometimes: cranial accessory, spinal accessory. Mainly motor Cranial and Spinal Roots Located in the jugular foramen. Controls the sternocleidomastoid and trapezius muscles, and overlaps with functions of the vagus nerve (CN X). Symptoms of damage: inability to shrug, weak head movement. XII Hypoglossal: Mainly motor Medulla
The PNS includes motor neurons, mediating voluntary movement; the autonomic nervous system, comprising the sympathetic nervous system and the parasympathetic nervous system and regulating involuntary functions; and the enteric nervous system, a semi-independent part of the nervous system whose function is to control the gastrointestinal system.