Hypoglossal nerve

Function

• Cranial nerve XII or simply CN XII
• It provides motor control of the extrinsic muscles of the tongue, in particularly responsible for protruding the tongue

• It also supplies movements including clearing the mouth of saliva and other involuntary activities.
• The hypoglossal nucleus is involved in unconscious movements relating to speech and articulation.

• Briefly saying, its damage causes difficulty in speaking, eating and chewing.

Nerve damage

• Tongue fasciculations
• Tongue Atrophy
• Tongue deviatation to one side
• Tongue may feel Thick / Heavy / Clumsy, results in slurred speech

Hypoglossal nerve carries lower motor neurons that synapse with upper motor neurons at the hypoglossal nucleus.

Related disease

• Medullary stroke
• Multiple sclerosis
• Guillain-Barre syndrome
• Infection
• Sarcoidosis

• Progressive bulbar palsy: Difficulty with tongue movements, speech, chewing and swallowing caused by dysfunction of several cranial nerve nuclei.
• Motor neuron disease is the most common disease affecting the hypoglossal nerve.