Human brain works backwards to retrieve memories

A new study, conductA new study, conduct ed at the University  of Birmingham now says that when we remember a past event, the human brain reconstructs that experience in reverse order.The study adds that understanding how the brain retrieves information could help better assess the reliability of eye witness accounts and various other social aspects.The study, published in Nature Communications, was carried out by researchers in the Centre for Human Brain Health. They reconstructed the memory retrieval process, using brain decoding techniques that make it possible to track when in time, a unique memory is being reactivated in the brain.Researchers found that, when retrieving information about a visual object, the brain focuses first on the core meaning and only afterwards recalls more specific details.Notably, this is in sharp contrast to how the brain processes images when it first encounters them.Speaking about it, lead author of the study, Juan Linde Domingo said, “We know that our memories are not exact replicas of the things we originally experienced.”He further added, “Memory is a reconstructive process, biased by personal knowledge and world views – sometimes we even remember events that never actually happened. But exactly how memories are reconstructed in the brain, step by step, is currently not well understood.”The study saw participants view images of specific objects and then learned to associate each image with a unique reminder word. They were later presented with the reminder word and asked to reconstruct the associated image in as much detail as possible.Brain activity was recorded throughout the task via 128 electrodes attached to the scalp, allowing the researchers to observe changes in brain patterns with millisecond precision. Finally the researchers trained a computer algorithm to decode what kind of image the participant was retrieving at different points in the task.Maria Wimber, senior author of the study inferred, “We were able to show that the participants were retrieving higher-level, abstract information, such as whether they were thinking of an animal or an inanimate object, shortly after they heard the reminder word.” (ANI)