The caroticotympanic nerves are nerves which supply the
eardrum
In the anatomy of humans and various other tetrapods, the eardrum, also called the tympanic membrane or myringa, is a thin, cone-shaped membrane that separates the external ear
The outer ear, external ear, or auris externa is the extern ...
("tympanum") and
carotid canal
The carotid canal is a passageway in the temporal bone of the skull through which the internal carotid artery enters the middle cranial fossa from the neck.
Structure
The carotid canal is located within the middle cranial fossa, at the petrous ...
. They are the postganglionic sympathetic fibers from
internal carotid plexus
The internal carotid plexus is situated on the lateral side of the internal carotid artery, and in the plexus there occasionally exists a small gangliform swelling, the ''carotid ganglion'', on the under surface of the artery.
Postganglionic sym ...
which enter the
tympanic cavity
The tympanic cavity is a small cavity surrounding the bones of the middle ear. Within it sit the ossicles, three small bones that transmit vibrations used in the detection of sound.
Structure
On its lateral surface, it abuts the external auditory ...
via the
caroticotympanic artery. These fibers join the
tympanic plexus
In the tympanic cavity, the tympanic nerve (a branch of CN IX) divides into branches which, along with sympathetic fibres from the carotid plexus, form the tympanic plexus. This plexus is located on the surface of the promontory.
This tympanic ple ...
which are located on the surface of the
promontory
A promontory is a raised mass of land that projects into a lowland or a body of water (in which case it is a peninsula). Most promontories either are formed from a hard ridge of rock that has resisted the erosive forces that have removed the so ...
.
See also
*
Caroticotympanic arteries
Auditory system
Nerves
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