Scientists could be one step closer to finding ways to reduce the impact of traumatic memories, according to a study from the University of A&M in Texas published recently in the journal Nature Neuroscience.
The report describes in detail a study by researchers from the Department of Psychological and Brain Sciences and the Institute of Neuroscience. Stephen Maren, a professor of psychological and brain sciences, said the group’s findings suggest that the procedures clinicians use to indirectly reactivate traumatic memories lead to a window where those memories can be changed or even completely erased.
In therapy, imaginary reminders are often used to safely restore traumatic memories of experiences. For example, Maren said a military veteran wounded by an improvised explosive device could be asked to re-experience trauma – such as the lights and sounds of an explosion – without negative consequences. The idea is that fear reactions can be alleviated through this exposure therapy.
One of the main challenges is when you do extinction procedures, it doesn’t erase the original memory of the trauma. It is always there and bubbles can form, which is what causes relapse in people who experience fear again. “
Stephen Maren, Professor of Psychology and Brain Science, University of A&M, Texas
With this in mind, the researchers hoped to answer whether they could isolate memory and trigger fear responses by artificial reactivation – and potentially disrupt the original memory itself. Maren said their findings suggest that the procedures currently used by clinicians to indirectly reactivate traumatic memories create an opportunity to change or eliminate them.
To do this, the researchers used a conditioning procedure in which the sign is indirectly associated with a terrible event. When the moment is presented later, it indirectly reactivates the memory of the event and increases the activity in the hippocampus, a brain area important for memory.
The study showed that indirectly reactivating the contextual memory of fear by re-exposing the sign can make the memory vulnerable to disturbances. Maren said more research is needed to answer whether scientists can permanently lose traumatic information.
Ressler, RL, and others. (2021) Secretly capturing and diminishing the memory of hippocampus-dependent fear. Nature Neuroscience. doi.org/10.1038/s41593-021-00825-5.