The boundary between epilepsy and movement disorders may sometimes be difficult to define. Clinical semiology, unbiased description of phenomena, is the first tool clinicians use in order to classify their patients. For many years the main task has been one of differential diagnosis. It was either epilepsy or a movement disorder. Yet, this is a biased approach as it implies that they cannot coexist. Not only can epilepsy masquerade as movement disorders, but movement disorders may be observed which are not easily differentiated from epileptic seizures; syndromes or diseases may associate both epilepsy and movement disorders occurring in the same patient or the same family. This is because a structural or genetic abnormality may determine both conditions. But if we need to break barriers which have been set for nosological purposes, we need to validate clinical semiology with clinical and experimental neurophysiology, functional neuroimaging, genetics and molecular biology. The purpose of this book is to present innovative information on the nosology and pathophysiology of motor epilepsy, myoclonus, paroxysmal dyskinesias and syndromes associating epilepsy and movement disorders in children and adults.

Chapter 1 examines the development of the concept of channelopathies as a crucial mechanism in the genetically determined epilepsies. Starting with benign familial neonatal convulsions, evidence for this has also been shown in autosomal dominant nocturnal frontal lobe epilepsy (ADNFLE), and in generalized epilepsy with febrile seizures plus (GEFS+). Interestingly, several different channelopathies may result in a similar, if not an identical, clinical picture, often due to mutations of different subunits of the same ion channels, or of different ion channels.