Henry Gustav Molaison, previously known as H.M., was an American memory disorder patient whose hippocampi, parahippocampal gyrus, and amygdalae were surgically removed in an attempt to cure his epilepsy. He was widely studied from late 1957 until his death. His case played a very important role in the development of theories that explain the link between brain function and memory, and in the development of cognitive neuropsychology, a branch of psychology that aims to understand how the structure and function of the brain relates to specific psychological processes. Before his death, he resided in a care institute located in Windsor Locks, Connecticut, where he was the subject of ongoing investigation.
When an operation left Henry Molaison unable to form new memories, he became the most important patient in the history of brain science. Neurologist Suzanne Corkin reveals what it was like to work with “HM” for 46 years
In 1953, a young man named Henry Gustav Molaison, of Hartford, Connecticut, lost his memory and helped to invent neuroscience. Henry Molaison’s amnesia was the result of a highly risky “psychosurgical” procedure, an operation designed to cure the debilitating epilepsy he had suffered since childhood. In an attempt to remove the part of the brain that was causing Henry’s fits, two holes were drilled in the front of his skull and a portion of his brain, the front half of the hippocampus on both sides, and most of the almond-shaped amygdala, was sucked out. The procedure, hopeful at best, went badly wrong and Henry, then aged 27, was left with no ability to store or retrieve new experiences. He lived the subsequent 55 years of his life, until his death in 2008, in the permanent present moment.