This review discusses the mechanisms of spontaneous blinking and the differential diagnosis and treatment of blepharospasm. Blinking rate is altered in various extrapyramidal disorders, suggesting an important role of the basal ganglia in generation and control of blinking. Focal dystonia is responsible for essential blepharospasm, Meige's syndrome, and tardive facial dystonia, but other biochemical, reflex, and neuromuscular mechanisms may be involved in this common and often disabling symptom.
Jankovic J, Havins WE, Wilkins RB. Blinking and BlepharospasmMechanism, Diagnosis, and Management. JAMA. 1982;248(23):3160-3164. doi:10.1001/jama.1982.03330230060037