[Current clinical-neurophysiological findings in absence epilepsies]

According to the international classification of epileptic seizures (1981) generalized seizures present ictal signs indicating seizure onset in both hemispheres whereas focal seizures present ictal signs pointing to one hemisphere at seizure onset. Recent neurophysiological studies using MEG, EEG, and fMRI suggest that in case of idiopathic generalized absence epilepsies, activity predominates in specific networks, which include frontoparietal cortical as well as subcortical areas of both hemispheres. In these network regions, epileptic activity can occur circumscribed and focal as spike or spike-wave activity but also widely distributed, bilateral, and homologous. As a consequence to the classification of "generalized" epileptic seizures and syndromes, it might be possible to distinguish a subgroup: regional bilateral homologous epilepsies. These must be distinguished from a pure culture of focal frontal lobe epilepsies, which can also be accompanied by the lead symptom of absences.