The pharyngeal plexus is a network of nerve fibers innervating most of the

palate The palate () is the roof of the mouth in humans and other mammals. It separates the oral cavity from the nasal cavity. A similar structure is found in crocodilians, but in most other tetrapods, the oral and nasal cavities are not truly separ ...

and

pharynx The pharynx (plural: pharynges) is the part of the throat behind the mouth and nasal cavity, and above the oesophagus and trachea (the tubes going down to the stomach and the lungs). It is found in vertebrates and invertebrates, though its st ...

. (The larynx, which is innervated by the superior and recurrent laryngeal nerves from

vagus nerve The vagus nerve, also known as the tenth cranial nerve, cranial nerve X, or simply CN X, is a cranial nerve that interfaces with the parasympathetic control of the heart, lungs, and digestive tract. It comprises two nerves—the left and righ ...

(CN X), is not included.) It is located on the surface of the middle pharyngeal constrictor muscle.

Sources

Although the '' Terminologia Anatomica'' name of the plexus has "vagus nerve" in the title, other nerves make contributions to the plexus. It has the following sources: * CN IX – pharyngeal branches of glossopharyngeal nerve – sensory * CN X –

pharyngeal branch of vagus nerve The pharyngeal branch of the vagus nerve, the principal motor nerve of the pharynx, arises from the upper part of the ganglion nodosum, and consists principally of filaments from the cranial portion of the accessory nerve. It passes across the i ...

– motor * superior cervical ganglion sympathetic fibers –

vasomotor Vasomotor refers to actions upon a blood vessel which alter its diameter. More specifically, it can refer to vasodilator action and vasoconstrictor action. Control Sympathetic innervation Sympathetic nerve fibers travel around the tunica media of ...

Because the cranial part of accessory nerve (CN XI) leaves the

jugular foramen A jugular foramen is one of the two (left and right) large foramina (openings) in the base of the skull, located behind the carotid canal. It is formed by the temporal bone and the occipital bone. It allows many structures to pass, including the ...

as a part of the CN X, it is sometimes considered part of the plexus as well.

Innervation

Sensory

The pharyngeal plexus provides sensory innervation of the

oropharynx The pharynx (plural: pharynges) is the part of the throat behind the mouth and nasal cavity, and above the oesophagus and trachea (the tubes going down to the stomach and the lungs). It is found in vertebrates and invertebrates, though its struc ...

and

laryngopharynx The pharynx (plural: pharynges) is the part of the throat behind the mouth and nasal cavity, and above the oesophagus and trachea (the tubes going down to the stomach and the lungs). It is found in vertebrates and invertebrates, though its struct ...

from CN IX and CN X. (The

nasopharynx The pharynx (plural: pharynges) is the part of the throat behind the mouth and nasal cavity, and above the oesophagus and trachea (the tubes going down to the stomach and the lungs). It is found in vertebrates and invertebrates, though its struct ...

above the pharyngotympanic tube and the

torus tubarius The base of the cartilaginous portion of the Eustachian tube (auditory tube) lies directly under the mucous membrane of the nasal part of the pharynx, where it forms an elevation or cushion, the torus tubarius or torus of the auditory tube, behind ...

is innervated by CN V₂).

Motor

The pharyngeal plexus, with fibers from CN IX, CN X, and cranial part of CN XI, innervates all the muscles of the pharynx (except

stylopharyngeus The stylopharyngeus is a muscle in the head that stretches between the temporal styloid process and the pharynx. Structure The stylopharyngeus is a long, slender muscle, cylindrical above, flattened below. It arises from the medial side of the ...

, which is innervated directly by a branch of CN IX). This includes the following muscles:

palatopharyngeus The palatopharyngeus (palatopharyngeal or pharyngopalatinus) muscle is a small muscle in the roof of the mouth. It is a long, fleshy fasciculus, narrower in the middle than at either end, forming, with the mucous membrane covering its surface, the ...

palatoglossus The palatoglossus or palatoglossal muscle is a muscle of the soft palate and extrinsic muscle of the tongue. Its surface is covered by oral mucosa and forms the visible palatoglossal arch. Structure Palatoglossus arises from the palatine aponeu ...

musculus uvulae The palatine uvula, usually referred to as simply the uvula, is a conic projection from the back edge of the middle of the soft palate, composed of connective tissue containing a number of racemose glands, and some muscular fibers. It also conta ...

, the pharyngeal constrictors, salpingopharyngeus plus others. Note that the intrinsic muscles of the larynx are innervated by the vagus nerve but not by the pharyngeal plexus. Instead, they are innervated by the recurrent laryngeal nerve and the external branch of the

superior laryngeal nerve The superior laryngeal nerve is a branch of the vagus nerve. It arises from the middle of the inferior ganglion of vagus nerve and in its course receives a branch from the superior cervical ganglion of the sympathetic nervous system. The superi ...

, branches of the vagus.

Additional images

File:Slide5ggg.JPG, Pharyngeal plexus File:Slide2mmm.JPG, Pharyngeal plexus

References