Subdural ictal EEG shows rhythmic spikes arising from the left hippocampal area followed by localised low-voltage fast activity and then sequential spikes spreading to the left subtemporal area (a) (arrows) but not to the left temporal neocortex. (b) About 12 seconds into the seizure, it spreads to the right temporal regions (both mesial and neocortical) (arrow heads) with continued activity in the left temporal region with offset in right temporal lobe (c). Prominent postictal slowing over the right temporal region is seen (c).