Vagus nerve
Vagus nerve is the tenth cranial nerve, which has branches to and from stomach and several other organs. The vagus nerve takes the route of the brain through the face and thorax to the abdomen. It is a mixed nerve that comprises parasympathetic fibres. The vagus nerve is composed of two sensory ganglia (masses of nerve tissue that transmit sensory impulses): the superior and the inferior ganglia. The branches of the superior ganglion stimulate the skin in the concha of the ear. Two branches arises from inferior ganglion : the pharyngeal nerve and the superior laryngeal nerve. The recurrent laryngeal nerve branches from the vagus in the lower neck and upper thorax to reach the muscles of the larynx (voice box). Cardiac, esophageal, and pulmonary branches also arises from vagus. In the abdomen the vagus innervates the greater part of the digestive tract, hunger and contraction of stomach.