Abstract. Department of Neurology Epilepsy is a chronic brain disease characterized by recurrent, unprovoked attacks of motor, sensory, or mental dysfunction resulting from excessive neuronal discharge in the gray matter of the cerebral cortex. From this definition it follows that no other clinical (mental changes) or electroencephalographic (epileptiform activity) signs alone can be the basis for a diagnosis of epilepsy. Epilepsy does not include single seizures, regardless of their clinical manifestations. Only repeated seizures are the basis for a diagnosis of epilepsy.