WHITE BEAR / MEMORY ERASURE
Is it possible to get rid of a memory you don't want?
Some memories are better forgotten — a traumatic event, a tragic love, or even a minor annoyance that ruined your mood for a day. Is there a way to deliberately forget something in the same way as we can deliberately memorize something? It’s hard to believe — but targeted reconsolidation might offer a way.
At first glance, targeted forgetting seems like science fiction — if it were possible to get rid of an unwanted memory by deliberate effort, we would probably know it. We can suppress thoughts — but there’s no evidence that this erases or even degrades specific memories.
Thought suppression might actually be counterproductive. In one famous study, when participants were asked, for five minutes, to try not to think a white bear, and then allowed to do so, they thought of the white bear obsessively, way more than those who were actually asked to think of the bear.
In the longer term, memory suppression by deliberate effort also does not seem to work. If it did, surely trauma victims would be better at it than anyone else — and yet, that’s not the case: evidence shows that people with PTSD are no better at blocking new negative memories than control subjects.
But maybe there’s a different way to think about memory erasure.
There was a second, less famous part in the “white bear” study. In a follow-up experiment, instead of just telling a new group of participants to suppress thoughts about the white bear, researchers instructed them to think of a red Volkswagen instead, any time the white bear came up in their mind.
And suddenly, the obsession that followed the suppression was gone. After spending five minutes replacing white bear with red Volkswagen, participants were no more interested in the white bear than the control group was — nowhere near as much as the group instructed to simply suppress white bear without any alternatives.
The strange part is, that group without alternatives thought it did have alternatives. Most of the participants, when tasked with not thinking of a white bear, immediately said “OK, I will think of something else”. But that was not enough. It had to be the Volkswagen, a fresh, novel competitor for the white bear.
Could it be the same with long-term memory? Maybe deliberate forgetting is not about erasing a memory, and neither it is about repressing it, as much as it is about replacing it with a new one.
We know from animal studies that any time a memory is recalled, it becomes malleable, for a period known as the reconsolidation window. It allows the brain to continuously update itself, incorporating new information into existing memories.
This is probably the reason why we have false memories. As we recall them over and over, we gradually modify them, sometimes to an unrecognizable point.
For instance, a week after the 9/11 attacks, psychologists interviewed 3000 people about their memory of the event. They repeated the interviews a year and three years later, and compared the content of the reports. A year-long memory turned out to be, on average, only 67% consistent with the week-long memory, and three years from the attacks, the consistency was at 57% — almost half of the content was fabricated. The emotional content of memories changed especially dramatically.
This probably happens to most of our memories. Reconsolidation means that no memory is final. Thinking about the past inevitably modifies the memory for the future.
But reconsolidation could also be a way to get rid of memories we do not want.
Some psychiatrists have begun incorporating this idea into their practice. They deliberately “activate”, in a patient, the reconsolidation window for the traumatic memory, for example by asking detailed questions about the event. Then, they immediately create an alternative, a surprising twist to the story that somehow contradicts the traumatic narrative, a “red Volkswagen” to replace the “white bear”.
The practice remains controversial. A recent meta-analysis criticized the lack of clearly established protocols for reconsolidation therapy, and pointed to a “significant risk of bias” in studies that support it. Clearly, more studies are needed to find the best way to harness reconsolidation as a therapeutic strategy.
But the meta-analysis also conceded that when it comes to treating PTSD, reconsolidation works. Despite the slight tang of exorcism, the practice really does succeed at replacing traumatic memories with their less traumatic versions.
So maybe this is the key to targeted forgetting: to get rid of a memory, overwrite it with new ones. When reminded of something you don’t want to remember, do your best to create a new memory of something related, but different.
This is a new way to think about reconsolidation. It doesn’t have to be a passive process — it is possible to take control of it, and turn it into memory erasure.
What you evidently cannot do is erase memory introspectively, from within your own head, just like you cannot suppress the “white bear” without a “red Volkswagen” offered instead. But you might be able to erase memory by deliberately exposing yourself to new experience — by actually doing something new.