[1] Epilepsy Research Group,
[2] Institute of Neurology,undefined
[3] National Hospital for Neurology and Neurosurgery,undefined
[4] National Society for Epilepsy,undefined
[5] Queen Square,undefined
[6] London WC1N 3BG,undefined
[7] UK Tel.: +44 171 916 0207; Fax: +44 171 837 3941; e-mail: j.duncan@ion.ucl.ac.uk,undefined