Memories are defined as affinity links between neurons. The act of recording a memory activates a specific group of neurons that exchange electrical signals; subsequently, upon recalling, this same neuronal set is reactivated. Although this mechanism is not yet fully elucidated by science, it is known that the hippocampus, a brain region, coordinates this process.
However, an experiment conducted on rats raised questions about the traditional model. A team of Japanese scientists subjected the laboratory animals to a state of 'artificial hibernation.' To achieve this, they administered an anesthetic to the rodents and then deactivated the hippocampal neurons for a period of 48 hours.
As a result of this intervention, about 60% of all synapses—the connections between neurons—in the hippocampus were removed, which theoretically should have led to the erasure of memories. However, when the rats were awakened, their memories remained intact. They were still able to remember two previous training sessions, which included navigating a maze and avoiding certain areas.
The scientists suggest that this finding may indicate that the maintenance of memories does not depend exclusively on the existing connections between neurons.