| either one of the tenth pair of cranial nerves, consisting of motor fibers that innervate the muscles of the pharynx, larynx, heart, and thoracic and abdominal viscera, and of sensory fibers that conduct impulses from these structures to the brain. |
| vagus nerve n. Either of the tenth and longest of the cranial nerves, passing through the neck and thorax into the abdomen and supplying sensation to part of the ear, the tongue, the larynx, and the pharynx, motor impulses to the vocal cords, and motor and secretory impulses to the abdominal and thoracic viscera. Also called pneumogastric nerve. [New Latin (nervus) vagus, wandering (nerve), from Latin.] |
vagus nerve n.
A mixed nerve that arises from numerous small roots from the side of the medulla oblongata and supplies the pharynx, larynx, lungs, heart, esophagus, stomach, and most of the abdominal viscera. Also called pneumogastric nerve, tenth cranial nerve.
vagus nerve
longest and most complex of the cranial nerves. The vagus nerve runs from the brain through the face and thorax to the abdomen. It is a mixed nerve that contains parasympathetic fibres. The vagus nerve has two sensory ganglia (masses of nerve tissue that transmit sensory impulses): the superior and the inferior ganglia. The branches of the superior ganglion innervate the skin in the concha of the ear. The inferior ganglion gives off two branches: the pharyngeal nerve and the superior laryngeal nerve. The recurrent laryngeal nerve branches from the vagus in the lower neck and upper thorax to innervate the muscles of the larynx (voice box). The vagus also gives off cardiac, esophageal, and pulmonary branches. In the abdomen the vagus innervates the greater part of the digestive tract and other abdominal viscera.
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