In the tympanic cavity

Tympanic cavity

The tympanic cavity is a small cavity surrounding the bones of the middle ear.It is formed from the tubotympanic recess, an expansion of the first pharyngeal pouch....

, the tympanic nerve

Tympanic nerve

The tympanic nerve is a branch of the glossopharyngeal nerve found near the ear.-Path:It arises from the petrous ganglion, and ascends to the tympanic cavity through a small canal, the fossula petrosa/tympanic canaliculus, on the under surface of the petrous portion of the temporal bone on the...

 (a branch of CN IX) divides into branches which form the tympanic plexus. This plexus is located on the surface of the promontory

Promontory of the tympanic cavity

The promontory of the tympanic cavity, better known as the cochlear promontory is a rounded hollow prominence, formed by the projection outward of the first turn of the cochlea....

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This tympanic plexus gives off:

• (1) the lesser petrosal nerve
  Lesser petrosal nerve
  The lesser petrosal nerve consists of parasympathetic fibres. It leaves the tympanic plexus to synapse in the otic ganglion, and eventually provide parasympathetic innervation to the parotid gland....
  
  
• (2) the Deep branch to join the greater petrosal nerve
• (3) branches to the tympanic cavity

The branches of the tympanic cavity provide innervation to the mucosa of the middle ear. The lesser petrosal nerve provides autonomic parasympathetic fibers that eventually innervate the parotid gland

Parotid gland

The paired parotid glands are the largest of the salivary glands. They are each found wrapped around the mandibular ramus, and secrete saliva through Stensen's ducts into the oral cavity, to facilitate mastication and swallowing and to begin the digestion of starches.-Location:The parotid glands...

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