A patient presents with loss of taste from the posterior one-third of the tongue and impaired pharyngeal sensation. Which cranial nerve is most likely injured?

• A Facial nerve (CN VII)
• B Hypoglossal nerve (CN XII)
• C Vagus nerve (CN X)
• D Glossopharyngeal nerve (CN IX) ✓

Explanation

The glossopharyngeal nerve (CN IX) provides taste and general sensation to the posterior one-third of the tongue, the fauces, and the pharynx. The facial nerve (CN VII) supplies taste to the anterior two-thirds. The vagus contributes to pharyngeal sensation but not posterior tongue taste. CN XII is motor to tongue muscles.

Reference: Gray's Anatomy, 42nd ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.