A man famous for his amnesia passed away

Last week Henry Gustav Molaison, known to his medical and scientific observers as H.M, died at age 82. At age 27 Molaison was the subject of surgery to treat severe seizures he experienced, but ultimately the surgery left him with amnesia--he could not remember anything beyond selected memories of his pre-surgery life.

Here's a snippet from the New York Times obituary for him:

For the next 55 years, each time he met a friend, each time he ate a meal, each time he walked in the woods, it was as if for the first time.

And for those five decades, he was recognized as the most important patient in the history of brain science. As a participant in hundreds of studies, he helped scientists understand the biology of learning, memory and physical dexterity, as well as the fragile nature of human identity.

From the Times account, it seems that he led a pleasant, if not traditionally fulfilling, life.

In conjunction with noting Mr. Molaison's death, Slate.com offered a brief explanation of amnesia, including this description:

There are two main types of amnesia: retrograde and anterograde. Retrograde means you lose your memories from before the surgery, injury, or whatever incident caused the memory loss. . . . Anterograde means you lose the ability to form new memories but can still recall things from before the inciting event. That was the case with H.M., who could remember scattered childhood memories.

(Photo by erat; used by permission.)