In a study not yet peer-reviewed that has just been presented at the conference of the European College of Neuropharmacology, held in Lisbon, the results of an animal study have been presented and that perhaps could help patients suffering from stress disorder post-traumatic disease (PTSD). Specifically, it is a protein that can be used as a brain marker to indicate whether emotional memories can be changed or forgotten.
Scientists know that long-term memories can be divided into two types: fact-based memory, where we can remember things like names, places, events, etc., and a kind of instinctive memory where we remember things like emotions and abilities. Scientists believe that these emotional memories can be modified in ways that help treat the trauma underlying PTSD. In 2004, work by scientists in New York showed that if animals were treated with the beta-blocker propranolol, this allowed them to forget about a learned trauma. However, the results have been difficult to reproduce, raising questions about whether the memories were modifiable at all.
Now, scientists at the University of Cambridge have shown that the presence of one particular protein, the “stem” protein, which acts as a scaffold for receptors that determines the strength of connections between neurons, determines whether memories they can be modified in animals treated with propranolol. If this protein is degraded, memories become modifiable. However, if this protein is present, this shows that the memories were not degradable, which explains why propranolol does not always cause amnesia.
The human brain is not like the brain of other animals
“We still don’t know if this protein is directly involved in memory degradation or if it is a by-product of a deeper reaction. What it does do is give us an entrance, a key to one of the first doors to understand the biochemistry of memory, “explained Amy Milton, lead author of the work. “These are really complex mechanisms, and we must bear in mind that this is work with animals; human brains are similar, but much more complex. We don’t see this leading to the kind of situation depicted in movies, where the protagonists can choose which memories to erase. But we hope that over time we will be able to identify the factors that make memories modifiable in animals and translate them to human patients. Ultimately, we hope to lessen the unconscious impact of traumatic emotional memories, the kind of trauma that can ruin the lives of people with PTSD. In ancient Greek legend they spoke of a drug, Nepenthe, which made them forget painful memories. We hope this is a step on the road to treatment ”, he concludes.
“This is an interesting job. Erasing what a memory does is extremely difficult, and this work brings us one step closer to understanding how they are retained and changed. There is a long way to go in this process and of course it will be difficult to transfer these steps to humans . But this gives us some hope that eventually we can help people suffering from traumatic stress memories, ”said Livia de Picker, a researcher at the University of Antwerp who was not involved in the study.
