Glossopharyngeal nerve

The glossopharyngeal nerve (from Greek glossa "tongue" and pharynx " throat "; " tongue -pharyngeal nerve" ) is the IX. Cranial nerve. It belongs to the so-called Vagusgruppe and is phylogenetically the third Kiemenbogennerv. The glossopharyngeal nerve innervates the tongue and the throat. He has sensitive, sensory (taste perception), motor and parasympathetic components.

• 3.1 Glossopharyngeuskrampf
• 3.2 Glossopharyngeuslähmung
• 3.3 glossopharyngeal

Origin

The core areas of its parasympathetic ( inferior salivatory nucleus ) and motor (nucleus ambiguus ) nerve fibers are located in the medulla oblongata. The nerve leaves the cranial cavity through the throttle hole ( jugular foramen ) where he receives sensory / sensory fibers from two ganglia. The most convenient still within the cranial cavity superior ganglion ( in animals: ganglion proximal ), the nerve cell bodies of the afferent fibers for touch, pain and temperature stimuli ( petrosal also ganglion in animals: ganglion distal ) in located outside the cranial cavity inferior ganglion of the the taste fibers. Both thus correspond to the dorsal root ganglia of the spinal nerves.

Ramifications of the glossopharyngeal nerve

Tympanic nerve

The tympanic nerve ( " tympanic cavity nerve" ) comes from the inferior ganglion and supplies the middle ear sensitive. In the middle ear it forms the tympanic plexus with, from which the lesser petrosal nerve arises, the parasympathetic fibers to the otic ganglion leads (so-called Jacobson anastomosis ). There the fibers can be switched to the second pass over the neurons, and auriculotemporal nerve to the parotid gland and the buccal nerve back to the gland, the secretion is stimulated.

Ramus pharyngeus

The pharyngeal ramus ( " Rachenast ") forms with vengeance branches of the vagus nerve and sympathetic fibers from the superior ganglion cervical pharyngeal plexus. This plexus supplies the striated muscles of the pharynx motor and pharyngeal mucosa sensitive. It is therefore also responsible for the gag reflex and the swallowing reflex.

Rami lingual

The Rami lingual ( " tongue branches " ) derive touch, temperature, pain and taste sensations from the posterior third of the tongue.

More branches

The ramus sinus carotici pulls the carotid sinus and carotid body. Both are sensors of the circulatory and respiratory center in the medulla oblongata.

The Rami tonsillares innervate the tonsils and the mucosa of the pharynx.

The Ramus caudalis musculi stylopharyngei innervated the same muscle, a Schlundkopferweiterer.

Diseases

Glossopharyngeuskrampf

The designated Glossopharyngeuskrampf, also known as throat spasm, and glossopharyngeal Pharyngismus Spasm (English), is caused by a spasm of the innervated by the glossopharyngeal muscles. It mainly occurs in tetanus, rabies and irritation caused by foreign body (see also Dysphagia ).

Glossopharyngeuslähmung

Damage to the glossopharyngeal nerve leads to paralysis of the pharyngeal muscles and thereby swallowing (dysphagia ). They are frequently associated with damage to the vagus nerve. Paralysis of the cranial nerves occur, for example in central nervous system diseases such as distemper and rabies and are cause for that patient ( animal, even human case of rabies ) not one of them are even able to drink. Also toxins of clostridia (tetanus, botulism ) can lead to disorders of nerve-muscle coupling and thus, inter alia, also to disturbances of the cranial nerves and act of swallowing.

Glossopharyngeal

This is a rare clinical picture as a form of neuralgia, which may be caused by some attacks like pain in the area of the hypopharynx, tongue base, tonsils and ear region with appropriate stimulation, for example, by chewing, swallowing, speaking or applying pressure about. With participation of the ramus sinus carotici can also a reflex bradycardia or asystole may occur. The cause is usually a local demyelination of the nerve branches by pulsation of an adjacent vessel. This can ( communicate information about pressure, touch, vibration and conscious proprioception ) on protopathische nerve fibers ( relay information about pain and temperature) come for transmitting electrical pulses from epicritic nerve fibers.