Background/Interictal/Activation

Please refer to specific syndromes and etiologies in which this seizure type occurs.

Ictal

With generalized tonic-clonic seizures, the ictal EEG is often obscured by artifact. Generalized fast rhythmic spikes are seen in the tonic stage. Bursts of spikes and after-coming slow waves are synchronous with clonic jerks. A postictal period of irregular slow activity follows. Although individual seizure onsets can appear localized, the location and lateralization are not consistent from one seizure to another.