What are Hemifacial Spasms?

3. Causes of Hemifacial Spasms

An irritated facial nerve is the most common cause of hemifacial spasm. This group of cells is the seventh cranial nerve and controls the muscles of the face. The facial nerve also transmits taste from the tongue and sensations in the ear. A small artery pressing on the facial nerve near the brain stem is usually the cause of irritation. Less common causes are nerve injuries, lesions or benign tumors putting pressure on the nerve, or abnormal blood vessel clusters at birth. Hemifacial spasms can be hereditary, but this is very uncommon.