Henry Molaison: the amnesiac well never forget | 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
Hm. (Henry Gustav Molaison (February 26, 1926 – December 2, 2008), previously known as H.M., was an American memory disorder patient whose hippocampus, parahippocampal gyrus, and amygdala were surgically removed in an attempt to cure his epilepsy. He was widely studied from late 1957 until his death.)
The Tragic Story of the Most Famous Amnesiac and Pictures of His Brain | Even after his death Henry Molaison continues to provide insights into how memory works; Dr Annese continues: “For many decades, it was thought the main area of damage responsible for H.M.’s amnesia was the hippocampus. However, these new findings show that a substantial portion of H.M.’s hippocampus may have been spared by the operation. Instead, H.M.’s entorhinal cortex [...] was almost completely destroyed.
In 1953, Henry Molaison underwent brain surgery for epilepsy, in which his hippocampus was removed. Molaison awoke free of seizures, but unable to retain long term memories. After his death in 2008, researchers froze and analyzed his brain to figure out what went wrong.