Internal laryngeal nerve

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The internal laryngeal nerve is the internal branch (ramus internus) of the superior laryngeal nerve. It descends to the hyothyroid membrane, pierces it in company with the superior laryngeal artery, and is distributed to the mucous membrane of the larynx.

Of these branches some are distributed to the epiglottis, the base of the tongue, and the epiglottic glands; others pass backward, in the aryepiglottic fold, to supply the mucous membrane surrounding the entrance of the larynx, and that lining the cavity of the larynx as low down as the vocal folds.

A filament descends beneath the mucous membrane on the inner surface of the thyroid cartilage and joins the recurrent nerve.

Above the vocal folds the sensory innervation of the larynx is via the INTERNAL LARYNGEAL NERVE. Below the vocal folds it is by way of branches of the RECURRENT LARYNGEAL NERVE.


Irritation of the internal laryngeal nerve results in uncontrolled coughing - usually as a result of food or water in the laryngopharynx.

Cranial nerves

I-IV: olfactory - optic - oculomotor - trochlear

V: trigeminal: semilunar ganglion
V1: ophthalmic: lacrimal - frontal (supratrochlear, supraorbital) - nasociliary (long root of ciliary, long ciliary, infratrochlear, ethmoidal) - ciliary ganglion - short ciliary
V2: maxillary: middle meningeal - in the pterygopalatine fossa (zygomatic, zygomaticotemporal, zygomaticofacial, sphenopalatine, posterior superior alveolar)
in the infraorbital canal (middle superior alveolar, anterior superior alveolar)
on the face (inferior palpebral, external nasal, superior labial, infraorbital plexus) - pterygopalatine ganglion (deep petrosal, nerve of pterygoid canal)
branches of distribution (palatine, nasopalatine, pharyngeal)
V3: mandibular: nervus spinosus - internal pterygoid - anterior (masseteric, deep temporal, buccinator, external pterygoid)
posterior (auriculotemporal, lingual, inferior alveolar, mylohyoid, mental) - otic ganglion - submandibular ganglion

VI: abducent

VII: facial: nervus intermedius - geniculate - inside facial canal (great petrosal, nerve to the stapedius, chorda tympani)
at exit from stylomastoid foramen (posterior auricular, digastric - stylohyoid)
on face (temporal, zygomatic, buccal, mandibular, cervical)

VIII: vestibulocochlear: cochlear (striae medullares, lateral lemniscus) - vestibular

IX: glossopharyngeal: fasciculus solitarius - nucleus ambiguus - sympathetic efferent fibers - ganglia (superior, petrous) - tympanic

X: vagus: ganglia (jugular, nodose) - Alderman's nerve - in the neck (pharyngeal branch, superior laryngeal, recurrent laryngeal) - in the thorax (pulmonary branches, esophageal plexus) - in the abdomen (gastric plexuses, celiac plexus, gastric plexus)

XI: accessory XII: hypoglossal