EEG findings may include the following: Epileptiform abnormalities in temporal lobe foci between seizures (interictal) in focal impaired-awareness seizures originating in the temporal lobe Interictal bilateral symmetric bursts of 4 - to 7-Hz epileptiform activity in primarily generalized tonic-clonic seizures Focal epileptiform discharges in focal-to-bilateral tonic-clonic seizures Spikes and slow-wave discharges occurring bilaterally at a rate of 3 / second and usually normal background EEG activity in typical absence seizures Slow spike and wave discharges usually at a rate of < 2.5 / second, typically with interictal disorganization of background activity and diffuse slow waves, in atypical absence seizures Bilateral polyspike and wave abnormality at a rate of 4 - to 6-Hz in juvenile myoclonic epilepsy However, normal EEG cannot exclude the diagnosis of epileptic seizures, which must be made clinically.