The HM Case Study HM was born in 1926. He injured his brain at age 7 when he fell off his bicycle, resulting in constant epileptic seizures that stopped him from living a normal life.
HM could do task and even commented it seemed easier than hen he expected, without realising he had done it hundred of times before.His anterograde procedural memory was totally affected and he also lost his memory for events that had happened after his surgery (moving houses, eaten meals...).
The HM Case Study In hopes of getting cured, HM and his family agreed to the experimental surgery by William Scoville, where he removed tissues from the medial temporal lobe (including the hippocampus) on both sides of HM's brain.
Despite the seizures being reduced drastically after the surgry, HM now suffered from anterograde amnesia, the ability to form new memories.Milner, a PhD student of Scoville followed up the surgery with cognitive test for 50 years after the original operation.
Milner observed that HM forgot daily events nearly as fast as they occurred, including the names of people he was just introduced to. However, HM could remember his early childhood memory and his intelligence remains as before.
An MRI scan of HM's brain was performed in 1992. In 2009, his brain was donated and sliced to be scanned onto computer in the new Brain Observatory at the University of San Diego.HM's contribution to science allowed us to discover memory systems in the brain constitute a highly specialised and complex system.