Our memory is selective and highly subjective. We subconsciously suppress some unpleasant memories, and some pictures from the past change in our imagination under the influence of the present. This often happens involuntarily, but what if we could intentionally get rid of some of the memories? Indeed, while a good experience can inspire a person, a bad one can completely break him (especially in the case of the development of post-traumatic syndrome). Science journalist Lauren Gravitz explains in an article on Aeon what opportunities modern science offers us to control memories and how we ourselves manage our memory without medication.
Interestingly, people don't necessarily want to be able to cut negative experiences out of their memory. For example, in 2010, Elizabeth Loftus of the University of California, Irvine (USA) conducted a study in which she asked survivors if they thought they should be given the opportunity to edit their memory, and if so, they would like to do it. … It turned out that out of almost a thousand participants, only 54% recognized the need to have such a choice and only 18% would want to use it.
In 2000, neuroscientists at New York University investigated the response of rodents to fear-inducing memories. They instilled in rats the association of a certain sound tone with a moderate shock, and when the animals heard it, they froze in fear. However, when a drug was injected into the amygdala of each of the experimental rats (and it is responsible for the formation of memory associated with fear and emotional impressions), a drug that prevents the formation of protein was injected and the sound was transmitted to them again, but without an electric shock, they forever stopped feel fear upon awakening this memory. The fact is, as scientists write in their study, that the transformation of new impressions (short-term memory) into long-term memory - this process is called its consolidation - involves the synthesis of proteins in the neurons of the brain. Disruption of this process means that the memories will disappear.
The drug that was administered to rats cannot be used in humans, Gravitz explains, but it can be replaced with propranolol. Already, this drug is usually given to patients suffering from post-traumatic stress disorder. Propranolol (also known as anaprilin), which is prescribed for blood pressure problems, is a substance that blocks beta-adrenergic receptors. If given to a distressed person within hours of the incident, it will reduce the response to the stress received. Moreover, propranolol can also influence a person's reaction to the subsequent replay of negative memories of what happened.
Alain Brunet, a psychologist at McGill University in Canada, found that if you give propranolol to a person with PTSD and ask them to write their story on paper an hour later, people no longer feel the negative emotions associated with a difficult experience. Apparently, Gravitz explains, propranolol blocks the action of the hormone norepinephrine, a neurotransmitter that stimulates the consolidation of emotional memory in the brain. It turns out that although the memories themselves remain, the person no longer remembers the horror that they instilled in him.
Since the human brain, by definition, remembers brighter episodes, especially negative ones, and more easily forgets simpler moments, we had to learn to somehow cope with a difficult experience and without external help. According to the theory of Michael Anderson, a neuroscientist at the University of Cambridge, we achieve this through the practice of retrieval suppression, that is, suppressing memories. As Gravitz explains, by deliberately distracting from unpleasant images from the past (which is the area of responsibility of the prefrontal cortex), we prevent them from consolidating in the hippocampus (which is responsible for actual memory).
Whether it is right to suppress memories can be debated for a long time. Anderson himself believes that this is not so bad (in this, perhaps, Sigmund Freud and many other psychoanalysts could argue with him). According to Anderson, paying too much attention to unpleasant memories, we provide ourselves with their "company". And this is absolutely useless.
Of the study participants, only 18% wanted to be able to edit memory
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Based on his research, he concluded that the suppression of memories also reduces their impact on a person's further perception of reality. In one experiment, Anderson showed participants a picture paired with a specific word. In the case where the word was highlighted in red, the participants had to suppress the memory of the image attached to it. Subsequently, the scientist presented the following picture to their attention: the object gradually appeared on the screen, on which there was initially visual noise, and the person had to say when he would be able to identify this object. It turned out that it was more difficult for the participants to recognize exactly those objects, the images of which were paired with the red words.
Using the same method (called "think / no-think", "think / do not think") in one of his last experiments, Anderson defined a phenomenon that he called "amnesic shadow" (translated - amnesic shadow). It turned out that people not only do not remember the object that they suppressed in their memory, but also those that went before and after it. This explains why it can be difficult for an accident victim to remember the circumstances under which it happened, notes Gravitz.
She herself experienced the consequences of this effect. Gravitz says that, unfortunately, she practically does not remember her father, and even what she remembers seems to be largely invented. The thing is that her father fell into unconsciousness due to a serious illness, and at some point it became too difficult for Gravitz to remember those times when he was still healthy. She deliberately displaced these pictures from her memory and tried never to think about them, thus practically editing her memories.
Perhaps scientific progress will bring us more effective techniques and drugs for memory editing than those that are now (and partially described above). Whether it will be good or not is definitely difficult to judge. Helping a person forget the nightmare that haunts him from the past is a great thing and in some cases even a life saved. Gravitz herself no longer tries to recreate lost memories, she has come to terms with her new reality and sees her personality exactly like that - with gaps in one of the most important chapters of the book of her life. But do not forget that to the question of whether a person's memories make him who he is, each of us must find his own answer.
Anastasia Zyryanova