Remember H.M.; imagine not being able to remember what you ate for breakfast, lunch, and dinner. Picture yourself at a dinner party unable to recognize any of the faces ofthe people whom you had met only minutes earlier. Recall that because H.M. suffered from epileptic seizures, doctors suggested that his hippocampus be removed. The result was both successful and unfortunate. H.M.'s seizures ended, but H.M. could not form any new memories. In addition to H.M.'s anterograde amnesia, he was unable to remember the 3 years of his life prior to the surgery (retrograde amnesia). Through endless studies and tests performed on H.M., many theories about learning and memory were revolutionized. Previous views focused on the concept of functional localization; this meant that specific brain regions were responsible for particular functions. This view (for some) was modified. Research from H.M. suggested that although functional localization is legitimate, there is a more complex circuitry associated with memory than once believed. It could have been hypothesized that because H.M. was incapable of transferring short-term memories into long-term memories, he could not have learned anything new. This was not entirely true. Remember that H.M. could learn skills such as the backwards mirror-drawing task. H.M. illustrated learning by improving at the task, despite his inability to recognize the test each day. This gave much insight into the process of converting short-term into long-term memory, a process called consolidation. H.M.'s ability to learn and improve at a task but to have no recollection of tracing the lines in the star gave novel insight into the role of the hippocampus in storing declarative memories.
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