What observation is made when assessing cranial nerves IX and X?

When assessing cranial nerves IX (glossopharyngeal) and X (vagus), the focus is on functions related to swallowing and the movement of the soft palate. Cranial nerve IX is primarily responsible for sensation in the posterior one-third of the tongue and the ability to trigger the gag reflex, whereas cranial nerve X innervates muscles involved in swallowing and controls the soft palate's movement. The symmetry of soft palate movement is assessed by observing whether the uvula is midline when the patient says "ah." If one side is paralyzed, the uvula will deviate towards the unaffected side.

Evaluating the ability to swallow is also crucial since any dysfunction in these nerves can lead to difficulties in swallowing (dysphagia) or issues with the gag reflex. This direct observation of soft palate movement and swallowing ability is a key component in assessing the integrity of these cranial nerves.

The other observations listed do not pertain to cranial nerves IX and X. For instance, assessing sharp/dull sensation in the face relates to cranial nerve V (trigeminal); evaluating jaw muscle strength pertains to the same nerve; and auditory sensory input relates to cranial nerve VIII (vestibulocochlear).