CN X: Vagus Nerve
On this page:Vagus Nerve PalsySomatic Motor PathwayVisceral Motor PathwaySomatic Sensory PathwayVisceral Sensory PathwaySpecial Sensory Pathway
Overview
Roles
- Somatic motor - pharyngeal & laryngeal muscles, palatoglossus
- Visceral motor (parasympathetic) - pharynx, larynx, thoracic and abdominal viscera
- Somatic sensory - back of ear, external auditory meatus, external tympanic membrane
- Visceral sensory -larynx, oesophagus, trachea, thoracic and abdominal viscera, aortic arch stretch receptors, aortic body chemoreceptors
- Special sensory (taste) - epiglottis
Vagus Nerve Palsy
Abnormalities
- Dysphagia
- Palate droop
- Diversion of uvula to one side
- Hoarseness
- Loss of gag reflex
Causes of Vagus Nerve Palsy
- Peripheral nerve trauma
- Peripheral nerve ischaemia
- Base of skull fractureInvolving the jugular foramen
- Motor neurone disease
Somatic Motor Pathway
- Cortical Centre
Primary motor cortex (precentral gyrus)Nucleus Ambiguus
MedullaForamen
Jugular foramenMuscles
Pharyngeal & laryngeal muscles, palatoglossus
Visceral Motor Pathway
- Dorsal Motor Nucleus
MedullaForamen
Jugular foramenMuscles
Pharynx, larynx, thoracic & abdominal viscera
Somatic Sensory Pathway
- Cortical Centre
Primary sensory cortex (postcentral gyrus)Spinal Trigeminal Nucleus
MedullaForamen
Jugular foramenSuperior GanglionReceptors
Back of ear, external auditory meatus, external tympanic membrane
Visceral Sensory Pathway
- Cardiovascular & Respiratory Centres
Reticular formation and hypothalamusSolitary Nucleus
MedullaForamen
Jugular foramenInferior GanglionReceptors
Larynx, oesophagus, trachea, thoracic and abdominal organs
Special Sensory Pathway
- Gustatory Cortex
InsulaThalamus
Ventral posteromedial nucleus (VPN)Solitary Nucleus
MedullaForamen
Jugular foramenInferior GanglionTaste Receptors
Epiglottis
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