Left vagus nerve (CN X)
Nervus vagus sinister
NervousNervesWhole bodyLeft side
- What it is
- The "wandering" nerve. From the jugular foramen it runs down the neck inside the carotid sheath behind the carotid artery and jugular vein, crosses the left side of the aortic arch (where it gives off the recurrent laryngeal nerve), passes behind the root of the left lung, spreads over the front of the oesophagus and enters the abdomen as the anterior vagal trunk onto the stomach.
- Function
- Parasympathetic supply to the heart, lungs and gut as far as the transverse colon; sensation from the larynx, airways and viscera; motor to the palate, pharynx and larynx (via the recurrent laryngeal).
- Size
- About 2-3 mm thick in the neck; ~60 cm long
- Clinical note
- Vagal stimulation slows the heart - the basis of carotid sinus massage and of fainting at the sight of blood. Its anterior gastric branches were once cut (vagotomy) to treat peptic ulcers.