|Nerve: Hypoglossal nerve|
|Hypoglossal nerve, cervical plexus, and their branches.|
|Gray's||subject #207 914|
|Innervates||genioglossus, hyoglossus, styloglossus|
The hypoglossal nerve is the twelfth cranial nerve (XII). The nerve arises from the hypoglossal nucleus and emerges from the medulla oblongata in the preolivary sulcus separating the olive and the pyramid. It then passes through the hypoglossal canal. On emerging from the hypoglossal canal, it gives off a small meningeal branch and picks up a branch from the anterior ramus of C1. It spirals behind the vagus nerve and passes between the internal carotid artery and internal jugular vein lying on the carotid sheath. After passing deep to the posterior belly of the digastric muscle, it passes to the submandibular region to enter the tongue.
Testing the hypoglossal nerve
The strength of the tongue can be tested by getting the person to poke the inside of their cheek, and feeling how strongly they can push a finger pushed against their cheek - a more elegant way of testing than directly touching the tongue.
Ipsilateral paralysis/pareisis of the tongue, results in contralateral curvature of the tongue (toward the unimpaired side of the mouth).
- NeuroNames hier-701
- MedEd at Loyola GrossAnatomy/h_n/cn/cn1/cn12.htm
- Norman/Georgetown cranialnerves (XII)