Ninth cranial nerve

Ninth Cranial Nerve

The ninth cranial nerve, also known as the glossopharyngeal nerve.

The ninth cranial nerve, also known as the glossopharyngeal nerve, is one of the twelve cranial nerves that originate from the brain. It is responsible for various functions including taste, swallowing, and speech.

Anatomy

The ninth cranial nerve is a mixed nerve, meaning it contains both sensory and motor fibers. It originates from the medulla oblongata, a part of the brainstem, and extends to the pharynx and tongue.

The course and distribution of the glossopharyngeal nerve.

Function

The glossopharyngeal nerve has several functions:

• Sensory: It carries sensory information from the posterior third of the tongue, including taste sensations. It also carries sensory information from the tonsils, the pharynx, and the middle ear.
• Motor: It provides motor innervation to the stylopharyngeus muscle, which is involved in swallowing.
• Parasympathetic: It carries parasympathetic fibers to the parotid gland, stimulating saliva production.

Clinical significance

Damage to the ninth cranial nerve can result in a variety of symptoms, including loss of taste, difficulty swallowing, and loss of gag reflex. This can be caused by a number of conditions, such as neuralgia, tumors, or stroke.

See also

• Cranial nerves
• Glossopharyngeal neuralgia
• Swallowing