Todd, Robert Bentley

Robert Bentley Todd (1809–60) was born in Dublin and graduated in 1831. He moved to London, where he became lecturer in anatomy and physiology at Aldersgate Medical School and subsequently chair of physiology and pathological anatomy at King's College. He edited the Cyclopaedia of Anatomy and Physiology in which he coined the terms afferent and efferent. In 1849, he described postictal paralysis (Todd's paralysis), i.e., a paralytic state that sometimes remains after an epileptic convulsion, in particular when the convulsion has affected only one side of the body or one limb. Todd himself attributed the phenomenon to postictal exhaustion of the involved neural tissues and the parts of the brain connected with them, a view later held by John Hughlings Jackson. William Gowers acknowledged that exhaustion may play a role with severe convulsions, but suggested an active inhibitory process as an explanation for postictal paralysis following a ‘slight fit.’ Todd also described some limited cortical and subcortical brain stimulation experiments on rabbits in 1849, and obtained motor responses at both sites, but did not fully understand their significance.