How some memories can be erased while leaving others intact

When a traumatic incident occurs to a person, it can make them experience fear and anxiety long after the event has happened. Typically taking the forms of anxiety and post-traumatic stress disorder (PTSD) after such an event occurs, the brain stores information about what happened during the experience. From every detail regarding the scene, what time, what (or who) was there at the time, if the person affected witnesses anything that reminds them of that incident, this can trigger an anxiety attack or post-traumatic stress. Researchers at the Columbia University Medical Center are trying to find a way to combat this. They looked at the marine snail Aplasia and found that different kinds of memories scored in the same neuron of the snail can in fact be selectively erased. This is an exciting discovery that hints that if applicable in humans, it may be possible to develop drugs that can help to "delete" certain memories that trigger anxiety and/or PTSD attacks, but not impact any other important memories. However, if one deletes the traumatic memory how will a person be able to make better-informed decisions so as not to repeat the incident? Dr. Samuel Schader (PhD, professor of neuroscience in the Department of Psychiatry at CUMC and co-author of the study) states that, "One focus of our current research is to develop strategies to eliminate problematic non-associative memories that may become stamped on the brain during a traumatic experience without harming associative memories, which can help people make informed decisions in the future - like not taking shortcuts through dark alleys in high-crime areas." Medical News Today reveals that in the new study, the researchers hypothesized that if two sensory neurons connected to a single motor neuron (like that of the marine snail Aplasia), then one sensory neuron could be stimulated to create an associative memory while the other produces a non-associative memory. Then, by measuring how strong each connection is, the researchers could examine what different stimuli was produced by maintaining a different form of Protein Kinase M (PKM) molecule, these being PKM Apl III for an associative synaptic memory and PKM Apl I for non-associative. What they found was that each of these memories could indeed be erased without making an impact on the other by blocking one of the PKM molecules. What this means is that as Jianguan Hu (PhD, associate research scientist in the Department of Psychiatry at CUMC and a co-author of the study) says, "Memory erasure has the potential to alleviate PTSD and anxiety disorders by removing the non-associative memory that causes the maladaptive physiological response." Not only this, but "By isolating the exact molecules that maintain non-associative memory, we may be able to develop drugs that can treat anxiety without affecting the patient's normal memory of past events."