The term epilepsy applies to a number of disorders of the nervous system centered in the brain and is characterized by recurrent seizures. 

A seizure involves muscle convulsions, partial or total loss of consciousness, mental confusion, or disturbances of bodily functions such as spots before the eyes, ringing in the ears, and dizziness. 

The frequency of epileptic symptoms varies widely across individuals.  Some people with epilepsy have many seizures each day while some can control their condition with medication, diet or other environmental adaptations, and go for months or even years without a seizure.