Vagus nerve

The vagus nerve (/ˈveɪɡəs/ VAY-gəs), historically cited as the pneumogastric nerve, is the tenth cranial nerve or CN X, and interfaces with parasympathetic control of the heart and digestive tract. The vagus nerves are paired; however, they are normally referred to in the singular.

Structure

Upon leaving the medulla oblongata between the pyramid and the inferior cerebellar peduncle, the vagus nerve extends through the jugular foramen, then passes into the carotid sheath between the internal carotid artery and the internal jugular vein down to the neck, chest and abdomen, where it contributes to the innervation of the viscera. Besides giving some output to various organs, the vagus nerve comprises between 80% and 90% of afferent nerves mostly conveying sensory information about the state of the body's organs to the central nervous system.

Right and left vagus nerves descend from the cranial vault through the jugular foramina, penetrating the carotid sheath between the internal and external carotid arteries, then passing posterolateral to the common carotid artery. The cell bodies of visceral afferent fibers of the vagus nerve are located bilaterally in the inferior ganglion of the vagus nerve (nodose ganglia).