Course Of FACIAL NERVE

The motor part of the facial nerve arises from the facial nerve nucleus in the pons while the sensory part of the facial nerve arises from the nervus intermedius.
The motor part and sensory part of the facial nerve enters the petrous temporal bone into the internal auditory meatus (intimately close to the inner ear) then runs a tortuous course (including two tight turns) through the facial canal, emerges from the stylomastoid foramen and passes through the parotid gland, where it divides into five major branches. Though it passes through the parotid gland, it does not innervate the gland. This action is the responsibility of cranial nerve IX, the glossopharyngeal nerve.
The facial nerve forms the geniculate ganglion prior to entering the facial canal.

[edit]Branches
Greater petrosal nerve - provides parasympathetic innervation to lacrimal gland, sphenoid sinus, frontal sinus, maxillary sinus, ethmoid sinus, nasal cavity, as well as special sensory taste fibers to the palate via the Vidian nerve.
Nerve to stapedius - provides motor innervation for stapedius muscle in middle ear
Chorda tympani - provides parasympathetic innervation to submandibular gland and sublingual gland and special sensory taste fibers for the anterior 2/3 of the tongue.
[edit]Outside skull (distal to stylomastoid foramen)
Posterior auricular nerve - controls movements of some of the scalp muscles around the ear
Branch to Posterior belly of Digastric and Stylohyoid muscle
Five major facial branches (in parotid gland) - from top to bottom:
Temporal (frontal) branch of the facial nerve
Zygomatic branch of the facial nerve
Buccal branch of the facial nerve
Marginal mandibular branch of the facial nerve
Cervical branch of the facial nerve
A traditional mnemonic device for the five major branches of the facial nerve is, "The Zebra Bummed My Cat." Other mnemonics for the divisions of the facial nerve include, "Today Zoe Bummed My Car", "To Zanzibar By Motor Car", "Tell Ziggy Bob Marley Called", "Ten Zebras Bullied My Cat", "Two Zulus buggered my cat" and "The Zoo Bought Monkey Clothes."