V Natarajan MD DM (Neurology) FRCP (Edinburgh) FAAN FIAN Former Professor of Neurology and Head of Institute of Neurology, Madras Medical College; Professor Emeritus, The Tamil Nadu Dr MGR Medical University, Chennai, Tamil Nadu, IndiaK Mugundhan MD DM (Neurology) FRCP (Glasgow) FRCP (London) FRCP (Ireland) FRCP (Edinburgh) FACP (USA) FICP FICCDMD FIMSAProfessor of Neurology and Head, Stanley Medical College, Chennai, Tamil Nadu, India