Living in the Moment
Written by Alan Bellows on 25/09/10 In memory of the Infamous H.M
“I don’t remember things,” Henry explained to the unfamiliar female interviewer. She seemed very curious about how he spends a typical day, and about what he had eaten for breakfast, but his efforts to summon the information from his mind were fruitless. He could easily answer her questions regarding his childhood and early adult years, but the indefinite expanse of time since then was bereft of memories. In fact, from moment to moment Henry feels almost as though he has just awakened from a deep sleep, with the fleeting remnants of a dream always just beyond his grasp. Each experience, dull or ...view middle of the document...
After exploring every other avenue known to contemporary medicine, Dr. William Scoville administered a radical resection of the man’s medial temporal lobes in a desperate bid to reclaim some quality of life for young Henry. In that respect the experimental operation was a success– the patient’s severe seizures were reduced dramatically after the operation– however the surgeon was distressed to discover that the removal of the hippocampi had stripped Henry of his ability to form new memories.
The development seriously hindered Henry from pursuing a normal life, but due to his condition he quickly became the world’s most famous subject in the study of the human brain. His real identity is a closely kept secret to this day, and he is referred to in medical literature by only his initials, “H.M.” However unfortunate, H.M.’s handicap helped to propel memory research beyond the realm of the philosophical for the first time in history. Earlier efforts to explore memory had been limited to animal studies, where scientists deliberately damaged various regions of lab animals’ brains to monitor any loss of memory functions. Such experiments were not only unpleasant for the animals, but frustratingly inconclusive for the researchers.
H.M. has been described as a friendly and articulate man with a higher-than-average IQ, sporting a charming personality in spite of his condition. Now in his early eighties, he still vividly recalls events from his childhood such as the stock market crash of 1929, but he is stricken with renewed grief every time he learns of his mother’s death. The grief is short-lived, however, as the substance of the news soon slips from the feeble grasp of his “working memory.” In an interview with researchers, he described the sensation:
“Right now, I’m wondering, have I done or said anything amiss? You see, at this moment everything looks clear to me, but what happened just before? That’s what worries me. It’s like waking from a dream. I just don’t remember.”
Like most anterograde amnesiacs, Henry experienced a degree of retrograde amnesia as well, blurring the details of the months leading up to the fateful operation.
Similar cases of anterograde amnesia have appeared over the years, often caused by Korsakoff’s Syndrome, a thiamine (vitamin B1) deficiency brought on by chronic alcoholism, malnutrition, eating disorders, or poisoning. This strongly suggests that thiamine is necessary to maintain the memory-writing features of the brain. Some abnormal viral infections can also produce the affliction, as is the case with a famed music expert named Clive Wearing. His ability to store memories was destroyed by a rogue infection of the herpes simplex 1 virus which attacked his brain’s hippocampus rather than triggering the typical cold sores. Other known causes include brain tumors, oxygen deprivation, and dementia-related diseases such as Alzheimer’s. In each instance it is found that the hippocampi have been compromised, indicating that...