Forgotten Memories Are Not Gone: Scientists Find Their Hidden Imprints in the Brain

Echoes of Past Experience

According to НВ — Техно: Memories that have stopped guiding behavior are not gone from the brain; they remain as hidden traces that can be awakened.

Date of publication: August 9, 3:00 PM

Forgetting is often mistaken for deletion, but this study supports the idea that the brain holds on to more than behavior reveals. Researchers from the Friedrich Miescher Institute for Biomedical Research in Switzerland, a team of neurobiologists, showed that a memory which no longer controls behavior can still leave a residual trace in the brain. In experiments on the fruit fly Drosophila melanogaster, they paired an odor with a mild electric shock, training the flies to avoid that odor. The avoidance response disappeared within 24 hours.

How a Memory Resurfaces

The hidden imprint was exposed when the flies were returned to the same environment, complete with the same lighting and surface texture: the memory of the dangerous scent returned completely. The brain creates two versions of each memory, one governing immediate behavior and the other stored silently in a separate group of neurons. When the active version is unavailable, the silent reserve copy can reactivate the neurons responsible for the behavior.

Surprisingly, a safe odor from the original training-never combined with a shock-also produced avoidance after being used as a reminder. This behavior indicates a false memory, and it shows that different neural pathways are involved in restoring authentic memories and generating illusory ones.

The results were published in the specialist journal Nature Neuroscience. Understanding these storage and retrieval mechanisms may help develop therapies for memory loss and related disorders. The researchers stress that memory traces remain in the brain forever, which opens up new avenues in neuroscience.

Because hidden memory traces exist, entirely new approaches to treating cognitive disorders may become possible, according to the findings.

A clearer view of how the brain stores and recalls memories could one day assist patients with memory loss and other conditions. The work also highlights the intricate relationship between memory and behavior, paving the way for further studies.

These findings not only shed light on the persistence of memories but also raise questions about the underlying mechanisms of neural development. For instance, recent research from Kyoto University explores how developing neurons can inadvertently damage their own DNA, potentially affecting memory formation and retrieval. Understanding these complex interactions could be vital in addressing memory-related disorders. Learn more about this intriguing connection between neuronal health and memory.