The Case Study of H.M.

The case study of Henry Molaison (H.M.) has been one of the biggest contributions to neuropsychology. Henry Gustav Molaison banged his head after being by a bicycle rider when he was nine and after that developed severe seizures. The scientists did not see into his head and were not even sure if the seizures had to do something with the accident. After 18 years, Molaison went to see Dr. William Beecher Scoville, a neurosurgeon at Hartford Hospital because he was blacking out frequently, had devastating convulsions and the quality of his life radically worsened. Dr. Scoville decided that the best option to help H.M. would be to surgically remove a portion of his temporal lobes, in particular hippocampus. After the surgery, seizures abated but there still were some other consequences, especially on his memory. A number of scientists were trying to figure out what were the consequences by giving H.M. memory tests and studying him thoroughly. After some tests, the scientist found out that H.M.'s short-term memory was completely fine; he could hold thoughts in his head for about 20 seconds. However, since it was impossible for him to hold onto these short-term memories, scientists concluded that hippocampus is responsible for forming and maintaining long-term memories. Yet H.M. was able to recall some of the earlier memories, he still had obstacles with placing them into the correct place in time. He was also unable to move memories from short-term to long-term stores so therefore he no longer had the ability to create new memories that could be later recalled. There were a lot of things learned on this case. He helped scientists understand the biology of learning, memory and physical dexterity, as well as the fragile nature of human identity. Before H.M. case, scientists believed that memory was widely distributed throughout the whole brain and that it was not dependent on any particular neural organ or region. However after this case they found out that there is a part in our brain that is responsible for forming long-term memories. This part is called hippocampus and it is located in the medial temporal lobes. Therefore, the case study of H.M. was really essential to development of neuroscience and to understanding the biological concept of memory.            “The study of H. M. by Brenda Milner stands as one of the great milestones in the history of modern neuroscience,” said Dr. Eric Kandel, a neuroscientist at Columbia University. “It opened the way for the study of the two memory systems in the brain, explicit and implicit, and provided the basis for everything that came later — the study of human memory and its disorders.”