[Pathogenesis of epilepsy in childhood and adolescence]

After a short discussion of the basic mechanisms of epileptic reactions, the conditions for epileptrogenesis are reviewed. As demonstrated by studies in animal models, distinctive structural and neurochemical characteristics of the brain tissue, probably genetically determined, build a main precondition for seizure manifestation. Starting from these basic concepts, the multifactorial pathogenesis of human epilepsy is discussed with special regard to genetic factors. The seizure liability results from the interaction of several independently transmitted genetic and lesional factors. None of these traits are epileptogenic by themselves, but effective only in interaction with other pathogenetic factors. Genetically determined "normal" structural and functional properties of the brain, e.g. expressed by generalized alpha rhythm, are involved in the complex pathogenesis of epilepsy. From a neurobiological point of view, epilepsy is always a multifactorially determined disease. The nowadays usual separation of idiopathic and symptomatic types of epilepsy may be helpful for communication in daily practice, but represents a simplification under pathogenetic aspects.