Facial Nerve


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Figure 7-1. Functional component overview of the facial nerve.

The facial nerve has four components with distinct functions:

Brancial motor
(special visceral efferent)
Supplies the muscles of facial expression; posterior belly of digastric muscle; stylohyoid, and stapedius.
Visceral motor
(general visceral efferent)
Parasympathetic innervation of the lcrimal, submandibular, and sublingual glands, as well as mucous membranes of nasopharynx, hard and soft palate.
Special sensory
(special afferent)
Taste sensation from the anterior 2/3 of tongue; hard and soft palates.
General sensory
(general somatic afferent)
General sensation from the skin of the concha of the auricle and from a small area behind the ear

Branchial motor fibers constitute the largest portion of the facial nerve.

The remaining three components are bound in a distinct fascial sheath from the branchial motor fibers. Collectively these three components are referred to as the nervus intermedius.