Question

1.      Who is H.M? What does his story tell us about the hippocampus? What kinds of memory impairments did he have, and what kinds of memories were spared? In your answer, describe and discuss types of memory impairments, and the types of memories that were spared, and include examples of each.

Answer 1

Henry Gustav Molaison, widely known as H.M. was an epilepsy patient. In an effort to cure his epilepsy, surgeons cut out two thirds of his hippocampi, parahippocampal cortices, entorhinal cortices, piriform cortices and amygdalae. His surgeries and the results were instrumental in facts about memory impairment and amnesia. His working memory and procedural memories were completely alright but his explicit memory to form new information was lost. After the surgery, he also experienced retrograde amnesia which caused the loss of past one or two year’s memory. He was able to learn new motor skills but he never remembered learning them.

His surgeries also shed new insights in understanding how particular areas of the brain were linked to specific processes of memory formation. It was found out that removing hippocampus caused memory loss and memory formation which happened in the case of H.M. His brain was kept in University of California and sliced into histological sections for creating a brain atlas.