Synonyms in a broader sense
vagus nerve, 10th cranial nerve, nerve, nervous system, nerve cell, CNS, parasympathetic nerve
Introduction
The nervus vagus is the 10th cranial nerve (X) and is clearly different from the other 11 cranial nerves. Its name means translated from Latin “the roving nerve”. Rightly so, because it does not – like the other cranial nerves – primarily serve the supply in the head area, but it supplies almost all organs of the body parasympathetically.
Therefore it is the largest nerve of the parasympathetic system. However, it is not only under the thumb of the parasympathetic nervous system, but also supplies muscles (e.g. those of the larynx) and serves the sensitive perception in certain areas (e.g. throat and larynx). It also conveys part of our sense of taste. The parasympathetic fibers of the vagus nerve originate in the cerebral nerve nucleus called nucleus dorsalis nervi vagi and then move as different small branches to the various recipient organs.
Course of the vagus nerve
The nervus vagus has the longest course within the 12 cranial nerves of the human brain, since it originates in the brain, but extends along the digestive system to deep regions of the abdomen. Its origin lies in several different cranial nerve nuclei in the extended spinal cord, which are responsible for the different qualities of the nerve. As soon as it leaves the elongated spinal cord, which is the lowest part of the brain and merges into the spinal cord, it exits through a small hole in the base of the skull.
It then runs down along the neck together with the carotid artery (A. carotis communis) and the great jugular vein (V. jugularis interna) in a connective tissue sheath (Vagina carotica) and enters the thoracic cavity. There the nerve runs more in the posterior area and in close proximity to the heart, lungs and esophagus. It attaches itself directly to the esophagus and accompanies it through the diaphragm into the abdominal cavity, which is its final destination. The nerve divides into many branches and supplies the digestive organs and kidneys. It is important to note that throughout its entire course from the brain to the abdominal region, the vagus constantly produces smaller nerve branches that supply the nearby organs.