Question

Cranial nerve VII (Facial Nerve) is a ‘mixed’ nerve (i.e., it has both sensory
and motor components). Its motor nucleus at the junction of the pons and
medulla innervates the muscles of the face.
(a) How does the motor innervation of the upper portion of the face differ from that of the lower?
(b) The sensory component of this cranial nerve mediates what specific sensory aspect of what
structure?

Answer 1

Motor innervation of upper part of the face comes from both upper and lower part of nucleus on ipsilateral side. But the lower part of face is only innervated by lower part of nucleus.

B) The facial nerve has a branch called chorda tympani nerve which has Special visceral afferent fibres. It carries taste sensations from the taste buds on the anterior 2/3 of the tongue except Vallate papillae. Its axons relay in the Nucleus Tractus Solitarius.