On March 14, 2005, at 1:40 p.m., William O.’s life ended, at least in his memory. That day, the 38-year-old British soldier had simply gone to the dentist to treat the nerve of a decayed tooth. A routine procedure. A few minutes later, however, his brain almost completely stopped recording new memories. His story, described in the scientific journal Neurocaseis today one of the most mysterious cases in modern neurology.
An ordinary day that turns upside down
There was no indication of what was going to happen. That morning, William is on a military post in Germany. The day begins like many others: a sports class, then some administrative tasks. In the afternoon, however, he has an appointment with the dentist to treat a seriously decayed tooth.
The practitioner then injects him with local anesthesia. A detail that William remembers perfectly. “I remember sitting in the chair and the dentist giving me local anesthesia… After that, the black hole.”
On the patient’s seat, the devitalization proceeds normally and ends around 2:30 p.m. But when the dentist asks him to get up, something is wrong. William is pale, weak, unable to get up. The dentist first thinks of vagal discomfort, a fairly common reaction to stress or pain. He gives him sugar and oxygen. But the patient’s condition does not improve. Around 5 p.m., William was rushed to the hospital.
A memory that lasts… less than two hours
In the emergency room, doctors discover a strange symptom: William is unable to remember what he has just experienced. A few minutes after a conversation, he has already forgotten it.
As the hours passed, his condition improved slightly. His immediate memory works, but only for a very short time. The doctors then measured a staggering phenomenon: William could not retain a memory for more than 90 minutes. Everything he learns then disappears.
The first hypotheses are worrying. A brain hemorrhage, for example, can sometimes occur after certain anesthesias. But the imaging tests are clear: his brain seems perfectly normal. After three days of hospitalization, William leaves the hospital. The mystery remains intact.
Every morning he thinks he has to go to the dentist
Months pass, but the situation does not improve. William returns to live in Britain with his family, in his childhood home. He recognizes the place from having lived there. But every morning the same scene repeats itself. He wakes up, looks around and wonders why he is in his mother’s house.
And above all, he is convinced of having an appointment with the dentist during the day. Because his last stable memory is that of local anesthesia at 1:40 p.m., March 14, 2005.
To understand what is happening to him, William must read a text, like a reminder, saved in his phone “Read first”. In it, he and his wife wrote the story of his accident and illness.
Amnesia: when the brain no longer prints the present
This disorder belongs to a category called anterograde amnesia. In this type of amnesia, old memories remain accessible, but the brain is no longer able to transform present experiences into lasting memories.
The most famous case is that of Henry Molaison, an American patient whose hippocampi, brain structures essential for memory, were removed during an epilepsy operation. But William’s case poses a major problem: his hippocampus seems intact. And above all, the MRIs do not reveal any lesions.
To understand what could be happening, we need to look at a fundamental process in the brain: memory consolidation, which transforms a fragile memory into a stable memory. During this phase, neurons modify their connections, called synapses, through the production of new proteins.
However, the time required for this consolidation is surprisingly close to what patients like William experience: 60 to 90 minutes. Some researchers therefore believe that William’s brain still functions normally to record an experience… but that he is no longer able to consolidate it. As if the brain’s printing press was still working… but running out of ink.
Why go to the dentist? The medical mystery remains unsolved
But one question remains: why would a simple visit to the dentist have triggered this?
The researchers explored several avenues:
- A rare reaction to anesthesia;
- A cerebral micro-event invisible on MRI;
- Psychological trauma;
- An abnormality in neuronal connections;
- A genetic predisposition triggered by stress.
None have been confirmed. For psychologist Gerald Burgess, who has followed William for years: “There could be a genetic predisposition that only manifests itself after a triggering event.”
As in “A Day Without End”
Despite everything, William has since led a relatively stable life. He can discuss, think, read, understand the world. His intellectual abilities are intact.
But his relationship with time is deeply disturbed. For him, his children are still the little ones they were in 2005. Every time he realizes that they have grown up, it’s a surprise. During an interview carried out in 2015, the man declared with emotion the limits of his perception: “I want to walk my daughter down the aisle and remember her. If they become parents, I would like to remember that I have grandchildren, and know who they are.”