CN IX: Glossopharyngeal
February 15th, 2021
On this page:Glossopharyngeal Nerve PalsyMotor PathwayParasympathetic PathwayVisceral Sensory PathwayGeneral Sensory PathwaySpecial Sensory Pathway
Overview
Roles
- Special sensory (taste) - posterior 1/3 of tongue
- Visceral sensory - carotid sinus baroreceptors, carotid body chemoreceptors
- Somatic sensory - external ear, internal tympanic membrane, upper pharynx, posterior 1/3 of tongue
- Somatic motor - stylopharyngeus
- Visceral motor (parasympathetic) - parotid gland
Glossopharyngeal Nerve Palsy
Abnormalities
- Loss of pharyngeal sensation / gag reflex
- Loss of taste of posterior 1/3 of tongue
- Xerostomia (dry mouth)
Causes fo Glossopharyngeal Nerve Palsy
- Tumour
- Infarction
- Base of skull fractureInvolving the jugular foramen
- Diptheria
Motor Pathway
Cortical Centre
Primary motor cortex (precentral gyrus)
Primary motor cortex (precentral gyrus)
Nucleus Ambiguus
Medulla
Medulla
Foramen
Jugular foramen
Jugular foramen
Ganglia
Superior (jugular) and
inferior (petrous) ganglia
Superior (jugular) and
inferior (petrous) ganglia
Division
Stylopharyngeal branch
Stylopharyngeal branch
Muscles
Stylopharyngeus
Stylopharyngeus
Parasympathetic Pathway
Hypothalamus
Inferior Salivatory Nucleus
Medulla
Medulla
Foramen
Jugular foramen
Jugular foramen
Superior (jugular) and
inferior (petrous) ganglia
inferior (petrous) ganglia
Tympanic Nerve
Tympanic Plexus
Lesser petrosal nerve
Otic ganglion
Parotid Gland
Visceral Sensory Pathway
Cardiovascular & Respiratory Centres
Reticular formation and hypothalamus
Reticular formation and hypothalamus
Solitary Nucleus
Medulla
Medulla
Foramen
Jugular foramen
Jugular foramen
Ganglia
Superior (jugular) and
inferior (petrous) ganglia
Superior (jugular) and
inferior (petrous) ganglia
Nerve to sinus
Receptors
Carotid sinus baroreceptors, carotid body chemoreceptors
Carotid sinus baroreceptors, carotid body chemoreceptors
General Sensory Pathway
Cortical Centre
Primary sensory cortex (postcentral gyrus)
Primary sensory cortex (postcentral gyrus)
Sensory Nucleus
Medulla
Medulla
Foramen
Jugular foramen
Jugular foramen
Ganglia
Superior (jugular) and
inferior (petrous) ganglia
Superior (jugular) and
inferior (petrous) ganglia
Pharyngeal branch
Receptors
External ear, internal tympanic membrane, upper pharynx, posterior 1/3 of tongue
External ear, internal tympanic membrane, upper pharynx, posterior 1/3 of tongue
Special Sensory Pathway
Gustatory Cortex
Insula
Insula
Thalamus
Sensory Nucleus
Medulla
Medulla
Foramen
Jugular foramen
Jugular foramen
Ganglia
Superior (jugular) and
inferior (petrous) ganglia
Superior (jugular) and
inferior (petrous) ganglia
Lingual branch
Taste Receptors
Posterior 1/3 of tongue
Posterior 1/3 of tongue
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