[1] Young Epilepsy, Res Dept, Lingfield RH7 6PW, Surrey, England
[2] Univ Gothenburg, Gillberg Neuropsychiat Ctr, Gothenburg, Sweden
[3] Crawley Hosp, Child Dev Ctr, Crawley, W Sussex, England
[4] UCL, Inst Child Hlth, Neurosci Unit, London, England
[5] Great Ormond St Hosp Sick Children, London WC1N 3JH, England
[6] Univ Edinburgh, Muir Maxwell Epilepsy Ctr, Edinburgh Neurosci, Edinburgh, Midlothian, Scotland
[7] Univ Vermont, Coll Med, Burlington, VT USA