n 1953 the neurosurgeon William Scoville removed much of the medial temporal lobes on both sides from a 27-year-old man with severe epilepsy, Henry Molaison. The seizures lessened. He could no longer form lasting new memories. Four years later Scoville and Brenda Milner reported him, as H.M., with other patients who had had similar operations (Scoville & Milner, 1957).

what it is, and where to read it

A paper in the Journal of Neurology, Neurosurgery and Psychiatry, free to read through PubMed Central. Most of the other patients had been operated on for psychiatric illness.

what it says

Removal of the hippocampus and nearby structures on both sides produced a severe, lasting loss of recent memory, while intelligence, perception and older memories were largely spared. The more of the hippocampus removed, the worse the loss. The paper ends with a warning against the operation.

what's contested

The extent of the lesion: later imaging, and the sectioning of his brain after his death in 2008 (Annese et al., 2014), showed that some posterior hippocampus remained and found a small frontal lesion. And the conduct of the research: Dittrich (2016) raised questions about consent and about records; MIT colleagues of Suzanne Corkin, who studied H.M. for decades, responded that the records were preserved, and more than two hundred scientists signed in her support (MIT News, 2016). From 1991 a court-appointed conservator gave consent on his behalf. We report the dispute; we do not settle it.

methodological critiques

A field built largely on one person: whatever was particular to H.M., his epilepsy, medication and history, travels with the conclusions. The early testing was informal by later standards.

later reception

H.M. was studied for more than fifty years by around a hundred investigators (Corkin, 2002)(Squire, 2009). The case separated memory from intelligence, and, through Milner's finding that he could learn a motor skill without remembering practising it, one kind of memory from another. Corkin wrote his life. His name was made public only at his death.

in the tour: the room called "The patients' room" has a placard called "Who spoke for him" ···

References

1. Scoville & Milner (1957). Loss of recent memory after bilateral hippocampal lesions. Journal of Neurology, Neurosurgery & Psychiatry. doi:10.1136/jnnp.20.1.11
2. Annese et al. (2014). Postmortem examination of patient H.M.’s brain based on histological sectioning and digital 3D reconstruction. Nature Communications. doi:10.1038/ncomms4122
3. Dittrich, L. (2016). Patient H.M.: A Story of Memory, Madness, and Family Secrets. New York: Random House.
4. MIT News (2016). "Faculty at MIT and beyond respond forcefully to an article critical of Suzanne Corkin." MIT News Office, August 2016, with a statement by James DiCarlo. news.mit.edu/2016/faculty-defend-suzanne-corkin-0809
5. Corkin (2002). What's new with the amnesic patient H.M.?. Nature Reviews Neuroscience. doi:10.1038/nrn726
6. Squire (2009). The Legacy of Patient H.M. for Neuroscience. Neuron. doi:10.1016/j.neuron.2008.12.023
7. Corkin, S. (2013). Permanent Present Tense: The Unforgettable Life of the Amnesic Patient, H.M. New York: Basic Books.

see also