VII Facial Nerve - Taste
Although taste is not typically assessed during a routine
neurological examination, the 7th nerve does supply
taste to the anterior two-thirds of the tongue and hard
and soft palates. This can be tested using salty, bitter,
sour or sweet solutions.
- the tongue is protruded and held gently by the examiner.
- a small sample of solution is applied to one side
of the anterior two-thirds of the tongue using a cotton
tipped applicator saturated with the solution.
- with the tongue still protruded, the patient should
be asked to point to a sign displaying one of the
four possible tastes.
- the patient is then given a small sip of water and
the test is repeated using an alternate stimulus.
- the reason the tongue is maintained protruded is
because if the patient were allowed to put their tongue
back in their mouth in order to verbalize their response,
they could masticate and transfer the stimulus to
the opposite side which could be affected if there
was a lesion of the 7th nerve.