In unilateral hypoglossal nerve damage all the following can occur EXCEPT:
|A||Tongue atrophy on same side|
|B||Loss of taste sensations|
|D||Tongue deviation to same side|
a. The motor innervation of the tongue is the hypoglossal nerve (XII), whereas the lingual nerve (V3), carrying taste fibers from the chorda tympani nerve, provides sensation for the oral tongue.
b. The hypoglossal nerve is the twelfth cranial nerve (XII), leading to the tongue. The nerve arises from the hypoglossal nucleus and emerges from the medulla oblongata in the preolivary sulcus separating the oliveand the pyramid. It then passes through the hypoglossal canal.
c. It supplies motor fibres to all of the muscles of the tongue, except the palatoglossus muscle, which is innervated by the vagus nerve (cranial nerve X) or, according to some classifications, by fibres from theglossopharyngeal nerve (cranial nerve IX) that "hitchhike" within the vagus. It controls tongue movements of speech, food manipulation, and swallowing.
e. Swallowing to clear mouth of saliva and other involuntary activities completed by the tongue are controlled by the hypoglossal nerve; however, most functions are voluntary. Voluntary control requires conscious thought and nerve pathways occur in the corticobulbar region in the spinal cord.
f. The function of the hypoglossal nerve in manipulation for speech contributes to learning languages