Background

The background EEG is normal.

Interictal

The interictal EEG is often normal, generalized spike-wave or fragments of generalized spike-wave may be seen.

Activation

EEG abnormality is enhanced by sleep deprivation, in drowsiness and in sleep. Generalized spike-wave often becomes fragmented with sleep deprivation or in sleep. Fragmented generalized spike-wave can appear focal or multi-focal but usually is not consistently seen in one area. The morphology of the focal spike-wave typically appears similar to the generalized spike-wave.

Ictal

The ictal EEG varies with the seizure type occurring, refer to individual seizure types for more information.