29 Junio 2017 16:59
Researchers hope the study could lead to new therapies for PTSD
It would appear that the premise of the film Eternal Sunshine of the Spotless Mind could soon become a reality. Scientists have discovered a way of selectively eliminating certain kinds of memories while retaining others. So far however, the experiment has only been carried out on Aplysia snails. Presumably Kate Winslet and Jim Carrey weren't available.
Joking aside, humans and snails share similar proteins inside the neurons responsible for memory formation. So these mollusks are actually good candidates for scientists' attempts to research and develop new therapies for treating post-traumatic stress disorder.
The team of researchers from Columbia University Medical Centre and McGill University wanted to discover whether a non-associative memory could be eliminated without affecting an associative one.
To explain the difference between the two, co-author of the study – neuroscience professor Samuel Schacher – uses the example of someone who gets mugged in a dark alley shortly after having seen a mailbox. After such an incident, a person may feel distress each time he or she sees a mailbox.
'Fear of dark alleys is an associative memory that provides important information – dark alleys may lead to another mugging – and is based on a previous associative experience,' wrote Schacher. 'Fear of mailboxes, however, is an incidental memory that is not related to the event. Selective erasure of this type of memory would be beneficial.'
Previously it was believed that both types of memories – associative and non-associative – were inseparable, and that one couldn't be destroyed without destroying the other. Researchers have now discovered that the strength of associative and non-associative memories are maintained by two different types of Protein Kinase M (PKM) molecules: associative memories use PKM Apl III while non-associative memories use PKM APl I. Non-associative memories can be eliminated by blocking the appropriate molecule.
'Memory erasure has the potential to alleviate PTSD and anxiety disorders by removing the non-associative memory that causes the maladaptive physiological response,' says Jiangyuan Hu, PhD, an associate research scientist in the Department of Psychiatry at CUMC and co-author of the paper. '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.'
Erasing the traumas that make everyday living difficult, without forgetting that one day we were mugged in a dark alley and that we should probably take a different route next time.