Giving patients an anesthetic can help them forget a troubling memory, according to a study published today in the journal Progress of science. This is the latest study of conditions that may prevent memories from sticking, and could be a step towards finding a technique that helps people cope with the harmful memories of anxiety, trauma or addiction.
The researchers showed 50 participants two different and unpleasant narrated slideshows. One was kidnapping children and the other was a car accident, according to study author Ana Galarza Vallejo, a neuroscientist at the Technical University of Madrid. A week later, scientists "reactivated" the memories of just one of the slideshows by showing participants an image and asking basic questions. Immediately after, all participants received propofol anesthetic and underwent endoscopy, which usually takes only a few minutes. (The participants had all been recruited from a hospital and had to undergo endoscopy anyway.)
In the last step, the scientists tested all participants on their ability to memorize both stories. Half were tested just after waking up and half 24 hours later. Patients tested immediately afterwards tended to remember both. Patients tested a day later did not remember the story "reactivated" or the story that had not been. been reactivated. This suggests that the combination of reactivation, anesthetic and timing prevented the memory from being installed.
The document is an interesting addition to the growing research on how the mind keeps memories, says Ravi Das, a psychologist from University College London who did not participate in the study. People thought that once you learned something, you got stuck forever, says Das. "We now know that when you recover memories in certain circumstances, it's a brief period (about two hours) during which these memories are unstable and you can interfere with them," he adds.
The challenge will be to apply these limited results to concrete examples rather than to a situation in which scientists would have given a troubling memory a week ago. In his own research, Das is investigating whether similar techniques can help reduce alcohol-related cravings and addictions, which is a much more complex task. For example, they will try to weaken the memory of environmental triggers (like a particular place) that make you want to drink. "During our studies, we had heavy drinkers and smokers. They have been drinking and smoking for 10 years. So it's a very different level of difficulty to reactivate and destabilize an old memory, "says Das.
Vallejo says the team is interested in doing more testing with these real-world examples, but other experts are questioning about the possibility of using anesthetic to clear traumatic memories. . Michael Saladin, a professor at the South Carolina Medical University who was not participating in the study, praised the smart idea of recruiting patients who were already going to undergo a study. routine anesthesia procedure. "But who the hell will use propofol for this type of intervention?", Asks Saladin, who also studies memory recovery and manipulation in the context of addiction. "I like the idea of proof of concept, but what are you doing with that now?" Is it clinically useful to move forward with a version of this? The answer is that it's a very big question mark.
Both Saladin and Das say that many clinicians and patients might be worried about a general anesthetic, except in cases of absolute necessity. This is why many similar researches have used a drug called propranolol, usually used to treat high blood pressure and requiring no medical intervention. lose consciousness to affect memories. Yet, sometimes, propranolol does not work either. This is why Saladin believes it is important to investigate other drugs that may be useful because there is no reason to believe that a given treatment will work in all conditions, for all people.
In the end, there are still many questions to ask, such as: what drugs work for which people, how do the results differ by gender, and how to clarify the problem of affected memory so that, as Das says, "Useful memories do not last to roll and weaken you. Saladin adds that this is a young domain. So there is not a lot of data available, but the good news is that if all goes well, patients will not have to take their medication on a chronic basis. Interventions would rather be "one of the most ideal uses of drugs": briefly and strategically.