[1] Univ Bonn, Dept Epileptol, D-53105 Bonn, Germany
[2] Inst Nazl Neurol C Besta, Milan, Italy
[3] Inst Child Hlth, London, England
[4] Great Ormond St Hosp Sick Children, London WC1N 3JH, England
[5] Hop Necker Enfants Malad, Serv Malad Metab & Neurol, Paris, France
[6] Med Univ Vienna, Brain Res Inst, Vienna, Austria
[7] CHU Vaudois, CH-1011 Lausanne, Switzerland