Interictal spiking is seen in the EEG of epileptic patients betweenseizures. To date, the roles played by interictal events in seizureoccurrence and in epileptogenesis remain elusive. While interictalspikes may herald the onset of electrographic seizures, experimentaldata indicate that hippocampus-driven interictal events preventseizure precipitation. Even less clear than the role of interictalevents in seizure occurrence is whether and how interictal spikescontribute to epileptogenesis. Thus, while plastic changes withinlimbic neuronal networks may result from ongoing interictal activity,experimental evidence supports the view that epileptogenesisis accompanied by a decrease in hippocampus-driven interictalactivity.