The 9th and 10th nerves are tested together. They are responsible for swallowing, phonation, guttural and palatal articulation (the 7th nerve has a component for labial articulation). The glossopharyngeal nerve also subserves taste to the posterior one-third of the tongue but this is rarely tested.
- check palatial elevation by having the patient sustain an “ah.” When observing palatal movement, look at the palate rather than the uvula.
- assess the gag reflex by gentling stroking the soft palate on each side.
- swallowing can be assessed by giving the patient a sip of water and observing them swallow.
- listen to the patient’s speech. Is there a nasal quality?
- assess palatal articulation with a “KA” sound, guttural with a “GO” sound and labial with a “PA” sound.
the palate should elevate symmetrically, both when sustaining an “AH” and in response to stimulation on either side. Some patients however do not have a gag response and this can be normal if it is absent bilaterally. Patients should also be asked if they feel the stimulus.
with unilateral palatal weakness, the palate fails to elevate on the weak side and the gag reflex will be absent on that side.