Tongue & Laryngeal-Pharyngeal Function (IX, X, XII)
The clinician may use the “gag-reflex” to simultaneously evaluate the glossopharyngeal, vagus, and hypoglossal cranial nerves. Upon opening the mouth, the tongue first should be evaluated for atrophy and movement to assess hypoglossal function. Depending on patient cooperation, the clinician then may insert a finger through the oral cavity into the oropharynx and laryngopharynx. The muscle tone and gag should be evaluated to assess pharyngeal branches of glossopharyngeal and vagal nerves. Clinical utility of this test is limited due to the variability in normal responses. Dysphagia is a more reliable indicator of cranial nerve IX and X dysfunction..