The Runwell Hospital was founded in 1936 and immediately began admitting its first patients. Originally located in the East Ham area of London, this institution was created exclusively for curing patients affected by mental health issues, and from the beginning, the Runwell proved to be a highly experimental hospital.

Although some of its practices would today be considered quite controversial, the Runwell was the first hospital to open an Electroencephalography Department and always possessed a cutting edge research team. It was in this new era that, following World War II, Professor John Arthur Nicholas Corsellis began his research on dementias, schizophrenia and other psychoses, eventually becoming one of the major experts of his time on seizure related disorders.

After spending part of his youth in pre-war Germany, Corsellis returned to London in the late 1930s, and received his medical degree from London Hospital in 1944. Unfortunately, shortly afterwards, Corsellis fell victim to tuberculosis. Although this experience barred him from ever again working closely with patients, his bed ridden time proved to be enlightening to say the least.

Inquisitive and methodological by nature, Corsellis spent all of his long convalescence in further developing his knowledge on neuroscience. After fully recovering from his illness, Corsellis entered Runwell Hospital as part of its research staff, and, under the supervision of then Superintendent Rolf Strom Olsen, built the foundations for a brilliant and successful career. Critical and analytical, Cornellis found the rigours of research and sample testing to be his natural habitat, hence, his personality had a deep impact of the success of his career.

During his long time spent in Runwell Hospital, Corsellis contributed enormously towards understanding seizure related illnesses, particularly epilepsy. In the 1950s he began his unique and original brain collection, which eventually grew into an extremely original archive. The study of the actual brains of patients who had died in the hospital might seem unsettling, but it was pivotal for further developing his research. Today, this collection is preserved in the West London Mental Health Trust, and is part of the tissue bank of the Trust, and used by researchers from all over the world. Corsellis left a strong legacy behind him.

His pioneering work performed at the Runwell Hospital has given the medical field very strong insights into psychiatric medical research. His friends and colleagues described him as a critical and very acute man, but not devoid of emotions. His entire life was propelled by his inquisitive nature and he was motivated by results rather than being credited for their discovery.