In 2005, a man went to the dentist to get a root canal. Getting into the chair and the dentist administering local anesthesia was the last thing he remembered.
Ten years later, "William" has no memory of what happened to him after he woke up from getting a root canal. To him, he was still a British soldier assigned in Germany. He doesn't know his children are 21 and 18 years old now. When he wakes up in the morning, to him, it's still the day he has to go to the dentist. He does remember things but the memory lasts for only 90 minutes.
According to doctors, William is showing signs of anterograde amnesia. He can't create new long-term memories but he still remembers everything from before his brain injury occurred. The cause of his injury is still uncertain because imaging scans don't show damage where damage should be found in cases of memory loss.
It's also possible for anterograde amnesia to set in after psychological trauma but his wife and doctors don't believe this is what could've happened to William because he has no history of emotional problems before he went in for a root canal.
William's grandfather died in the same week he went to the dentist so the event was initially thought of as the trigger for what he is going through now. And while the general consensus now is that his condition is closest to anterograde amnesia, William was diagnosed initially with dissociative amnesia.
Without the presence of changes or damage in the brain, doctors believe that William can't make new long-term memories because of protein synthesis breaking down in the brain. Memories are consolidated with the production of certain proteins. If the process is impeded, memory consolidation fails or only partly succeeds.
How did William managed to last a decade without remembering anything from before his trip to the dentist in March 2005? He has an electronic diary. His wife reminds him every morning to check it out when he starts wondering what's happening. She's even set up a "Read This First" section to get him abreast of his situation.
Researchers are studying William's case and have detailed their work in the journal Neurocase.
Photo: Linda Tanner | Flickr
