Kalyan B Bhattacharya MD DM MAMS FIAN FRCP (Edin)Adviser and Senior Consultant, Department of Neurology, Medica Superspecialty Hospital; Formerly Professor and Head, Department of Neurology, RG Kar Medical College, Kolkata, West Bengal, IndiaGagandeep Singh MD DM (Neurology) FAMS FRCP (London) FIAN FICPProfessor and Head, Department of Neurology, Dayanand Medical College and Hospital, Ludhiana, Punjab, India; Honorary Senior Research Fellow, Department of Clinical and Experimental Epilepsy, Institute of Neurology, Queen Square, London, UK