Page 128 - Edited - Webster HEAD AND NECK - part 2-Merge PDF
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NERVE                                  COMPONENTS                               LOCATION OF CELL                        PERIPHERAL                              FUNCTION
                                                                                                   BODIES OF FIBRES                        DISTRIBUTION




         IX       Glossopharyngeal                         Afferent (sensory)

                  [because it supp-                        i) Visceral                             Inferior glosso-                        Posterior third of tongue                Chemoreception: Taste,
                  lies largely the                         (parasympathetic)                       pharyngeal ganglion                      Carotid body                            Blood pCO 2/[H ]
                                                                                                                                                                                                     +
                  tongue (Greek:                                                                   (asynaptic) in jugular                                                           monitoring
                  "glossa"), and                                                                   foramen
                  pharynx]                                 ii) Somatic                             Superior glosso-                        Posterior third of tongue,               Touch, etc. Reflex control of

                                                                                                   pharyngeal ganglion                      oropharynx and isthmus,                 swallowing cf "gagging" reflex
                                                                                                   (asynaptic)                              middle ear cavity                       leading to vomiting




                                                           Efferent (motor)
                                                           i) Parasympathetic                      1. Presynaptic axons from               Parotid salivary gland                  Secretomotor -
                                                                                                   cell bodies in brainstem                                                        Salivation
                                                                                                   2. Cell bodies of post-
                                                                                                   synaptic fibres in otic
                                                                                                   ganglion
                                                           ii) Somatic                             Brainstem                               Skeletal muscle of                      Swallowing; modulation                          HN 318
                                                                                                                                           upper pharynx; stylo-                   of phonation by varying

                                                                                                                                           pharyngeus                              configuration of pharynx




         X        Vagus                                    Afferent (sensory)
                  (Latin "wanderer"                        i) Somatic                              Superior vagal ganglion                 Mucous membrane of laryngo-             Touch, pain, temperature.
                  because of its                                                                   in jugular foramen                      pharynx, larynx and upper               Protection of airways: reflex control
                  wide distribution                                                                (asynaptic)                             trachea                                 or generation of swallowing,
                  c.f. English words                                                                                                                                               coughing, gagging, etc.
                  "vagrant, vagabond".)                    ii) Visceral                            Inferior vagal ganglion                 Lower respiratory tree and              Distension detection (Hering-Breuer
                                                           (parasympathetic)                       just below jugular foramen              and lungs.                              reflex); reflex coughing

                                                                                                   (asynaptic)                             Carotid sinus; Aortic arch;             Blood pressure monitoring
                                                                                                                                           abdominal veins
                                                                                                                                           Gastro-intestinal tract to              Detection of gut distension
                                                                                                                                           splenic flexure                         and movements'






        cranerv2                                                                                                   4
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