Facial Nerve: Functional Components

• Premotor cortex →motor cortex →corticobulbar tract→bilateral facial motor nuclei (pons) →facial muscles
• Stapedius, stylohyoid, posterior digastric, buccinator

General Visceral Efferent/Parasympathetic:

• The brainstem general visceral efferent column nuclear groups includes :

1. Edinger Westphal nucleus at rostral levels of the midbrain
2. Superior salivatory nucleus in the lower pons
3. Inferior salivatory nucleus  
4. Dorsal vagal nucleus in the medulla oblongata. 

Superior salivatory nucleus (pons) 

Nervus intermedius  →Chorda tympani →joins lingual nerve→submandibular ganglion→postganglionic parasympathteic fibers→submandibular and sublingual glands 

          ↓

Greater/superficial petrosal nerve

Facial hiatus/middle cranial fossa

Joins deep petrosal nerve (symp fibers from cervical plexus)

Through pterygoid canal (as vidian nerve)

          ↓

Pterygopalatine fossa

          ↓

Spheno/pterygopalatine ganglion

Postganglionic parasympathetic fibers

Joins zygomaticotemporal nerve(V2)

Lacrimal gland & seromucinous glands of nasal and oral cavity

 General Somatic Afferent/Sensory

• Sensation to auricular concha, EAC wall, part of TMJ, postauricular skin
• Through Cell bodies in geniculate ganglion
• Proprioseptive impulsesfrom muscles of face through V C.N. to mesencephalic nucleus

• Provide sensation to the soft palate and parts of the nasal cavity
• GVA create referred pain by activating general somatic afferent fibers where the two meet in the posterior horn of the spinal cord (dorsal horn).
• The general visceral afferent column is represented by part of the dorsal nucleus of the vagus nerve.