Henry Gustav Molaison (H.M.)

Henry Gustav Molaison, commonly known as H.M., was a man who became famous in psychology and neuroscience after undergoing brain surgery in 1953 to treat his severe epilepsy. The surgery removed parts of his hippocampus, leading to profound memory loss. While H.M. could recall memories from before the surgery, he was unable to form new long-term memories. His condition provided key insights into how memory works, particularly the distinction between short-term and long-term memory. H.M.'s case has significantly influenced our understanding of memory and the brain, making him a pivotal figure in the study of neuropsychology.