According to some recent research, really many memories are not completely erased from our hard drive although we think otherwise. Because, where does the lost memory go? Is there a space that collects what one day were data, experiences, dreams and that we have forgotten today, at least with our conscious brain? Science and philosophy have been trying to find out for centuries. If memory has some kind of physical format, if it obeys chemical and neurological phenomena that leave a mark, why sometimes forgetting is irreversible? Is it that the lived experience is erased forever or are we simply not able to rescue it from the place where it is stored?
Well, some research may have the answer. For example, a study published in the journal Neuron detected patterns of neuronal activation that corresponded to memories that the volunteers had taken for granted. One of the authors of the research, Jeffrey Johnson, from the University of California at Irvine, concluded that, "although the brain still retains certain information, we may not always have access to it." When we try to evoke a face, something funny that happened to us or a delicious meal, we activate the necessary neurological elements to assemble the pieces. What happens, then, with incomplete memories? Why is only part of these patterns set in motion? What happens to the rest?
Another investigation, conducted with mice by the RIKEN-MIT Center for Neural Circuit Genetics of Japan, has attempted to answer these questions. And its final conclusion is that the biochemical traces that correspond to supposedly faded memories can be reactivated. To verify if this was the case, the scientists injected some rodents with an inhibitory substance of certain neurons and made them amnesic. Then they placed all the animals in an environment where they could avoid or not electric shocks to those who had previously been subjected.
Although the forgetful returned to the place of unpleasant sensation, the researchers managed to reactivate their lost memories by sending micropulsations of blue light through a technique called optogenetics to nerve cells previously turned off by the drug. The result was that, from the intervention, the mice began to avoid the place where they received the electric shock. That is, the mice remembered again; They moved away from the places where they knew something nasty would happen to them. Or, what is the same, the induced amnesia had not erased his memories but had disabled his ability to recall the scenes.
An amnestic mouse does not lose memory, but loses the ability to recreate in the mind the events that are stored in memory. It is as if we had the memories archived in a computer and we lost the password to access them. The information is there, but we can not rescue it.
These works support the hypothesis that there is a large number of events that are not permanently erased from our brain. What happens is that we lose the ability to remember them, but experts in this field think that it will be possible to develop artificial techniques to do so.
