The Vagus Nerve

Key points

• • The vagus is the tenth cranial nerve; it is mixed, carrying motor, sensory and a large parasympathetic supply, and it leaves the skull through the jugular foramen.
• • It supplies most muscles of the pharynx and larynx, so damage causes hoarseness, a weak cough and difficulty in swallowing.
• • Its parasympathetic fibres slow the heart and drive the secretion and movement of the gut as far as about the middle of the transverse colon.
• • The recurrent laryngeal branch loops under the arch of the aorta on the left and under the subclavian artery on the right, so chest disease can affect the voice.
• • It carries taste from the epiglottis and sensation from part of the external ear, the pharynx and the larynx.