The researchers used neuroimaging techniques to record patterns of brain activity. They taught a group of healthy adults images of faces and scenes, and asked them to make an effort to remember or forget those that were pointed out to them.
Instead of analyzing what happened in the brain areas involved in the control of information and long-term memory-the prefrontal cortex and the hippocampus-they focused on the regions linked to perception, especially the visual cortex, and in the patterns of activity that correspond to the representations made by the memory of complex visual stimuli.
They observed that, as was suspected, people have some capacity to decide what we forget, and that starting it requires moderate brain activity in areas related to the senses and perception, greater than what is required to fix a memory. According to Tracy Wang, psychologist and principal author of the study, "is the intention to forget what increases brain activity, and when it reaches a certain threshold, we begin to forget that experience that affects us."
The researchers also found that study subjects tended to forget scenes more than faces; The latter usually provide us with much more emotional information, which confirms that feelings play a decisive role in the memory mechanisms of human beings.
This work affects something known: memory is dynamic. The brain builds from the experiences and sensations a memory that does not remain frozen: the neural circuits modify it in the light of new experiences, or eliminate it, in processes that usually take place when we sleep.
Jarrod Lewis-Peacock, one of the authors of the study, said on the UT website that "now that we have discovered indications of how the brain works to weaken certain memories, we can use this knowledge to develop treatments that help people get rid of of memories that do them a lot of psychological damage, so much so that they can make them sick ".
