Seizures are episodes of neuronal hyperactivity most commonly resulting in sudden, involuntary muscular contractions. They may also manifest as sensory disturbances, autonomic dysfunction and behavioral abnormalities, and impairment or loss of consciousness. Descriptions and classifications of seizures are complex and subject to change, because the etiology and pathogenesis of most seizures remain to be elucidated.
For the purpose of background incidence rates convulsion will be limited to generalized convulsions.