Memory is not videotape. False memories and how they are formed

2024 Author: Seth Attwood | [email protected]. Last modified: 2023-12-16 15:55

Usually we are confident in the inviolability of our memories and are ready to vouch for the accuracy of the details, especially when it comes to events that are truly important to us. Meanwhile, false memories are the most common thing, they inevitably accumulate in the memory of each of us and can even be considered as a certain good. For more information on how false memories are born and function, as well as what they are for, read our material.

New Year is a nostalgic winter holiday, which for many is almost inextricably linked with fond memories from childhood. The noise of the TV, on which from the very morning they play "Irony of Fate" and "Harry Potter", delicious smells from the kitchen, cozy pajamas with little yellow stars and a ginger cat Barsik constantly getting underfoot.

Now imagine: you are gathering at the family table, and your brother tells you that in fact Barsik escaped in 1999, and "Harry Potter" began to be shown on TV only six years later. And you didn't wear pajamas with asterisks because you were already in seventh grade. And for sure: as soon as the brother reminds of this, the colorful memory crumbles to pieces. But why did it seem so real then?

Endless amnesia

Many people are convinced that human memory works like a video camera, accurately recording everything that happens around. This is especially true of personally significant events associated with the sudden experience of strong emotions.

So, sharing memories of a car accident, a person very often can remember not only what he did and where he was going, but also, for example, what the weather was outside the window or what was playing on the radio. However, research shows that things are not so simple: no matter how vivid and vivid a memory may be, it is still subject to "corrosion".

Scientists have started talking about the imperfection of memory for a long time, but it was most clearly demonstrated by Hermann Ebbinghaus at the end of the 19th century. He was fascinated by the idea of "pure" memory and proposed a method of memorizing meaningless syllables, which consisted of two consonants and a vowel sound between them and did not cause any semantic associations - for example, kaf, zof, loch.

During the experiments, it turned out that after the first unmistakable repetition of a series of such syllables, information is forgotten quite quickly: after an hour, only 44 percent of the learned material remained in memory, and after a week - less than 25 percent. And although Ebbinghaus was the only participant in his own experiment, subsequently it was repeatedly reproduced, obtaining similar results.

Here you will probably rightly be indignant - after all, meaningless syllables are not the same as the significant moments of our life. Is it possible to forget your favorite children's toy or the patronymic of the first teacher? However, more recent research shows that even our autobiographical memory retains a very small fraction of the experience.

In 1986, psychologists David Rubin, Scott Wetzler and Robert Nebis, based on a meta-analysis of results from several laboratories, plotted the distribution of the memories of the average person at the age of 70. It turned out that people remember the recent past quite well, but when moving back in time, the number of memories sharply decreases and drops to zero at about the age of 3 years - this phenomenon is called childhood amnesia.

Subsequent research by Rubin showed that people do remember some events from early childhood, but most of these memories are the result of completely normal retrospective implantation, which often occurs during dialogues with relatives or viewing photographs. And, as it turned out later, the implantation of memories occurs much more often than we used to think.

Rewrite the past

For a long time, scientists were convinced that memory is something unshakable that remains unchanged throughout our life. However, already at the end of the 20th century, strong evidence began to emerge that memories could be planted or even rewritten. One of the proofs of the plasticity of memory was an experiment conducted by Elizabeth Loftus, one of the most prominent cognitive psychologists of our time dealing with memory issues.

The researcher sent men and women between the ages of 18 and 53 a booklet containing four childhood stories, as narrated by an older relative. Three of the stories were true, while one - the story of a participant being lost in a supermarket as a child - was false (although it contained truthful elements, such as the name of the store).

The psychologist asked the subjects to recall as many details as possible about the described event, or write “I don’t remember this,” if no memories were preserved. Surprisingly, a quarter of the subjects were able to talk about events that never happened. What's more, when participants were asked to find a false story, 5 out of 24 people made a mistake.

A similar experiment was carried out several years ago by two other researchers, Julia Shaw and Stephen Porter. Psychologists, using a similar method, were able to get students to believe that they had committed a crime as a teenager.

And if in the Loftus experiment the number of people who managed to "plant" false memories was only 25 percent of the total number of participants, then in the work of Shaw and Porter this figure increased to 70 percent. At the same time, the researchers emphasize that the subjects were not stressed - on the contrary, the scientists communicated with them in a rather friendly way. According to them, in order to create a false memory, it turned out to be enough authoritative source.

Today, psychologists agree that retrieving a memory can be a reason for changing previously acquired experiences. In other words, the more often we get episodes of our life out of the “distant box”, the more likely they are to acquire new colorful and, alas, fake details.

In 1906, Times Magazine received an unusual letter from Hugo Münsterberg, head of the psychology laboratory at Harvard University and president of the American Psychological Association, describing a case of a false confession to a murder.

In Chicago, a farmer's son found the body of a woman who was strangled with wire and left in the barnyard. He was charged with murder, and despite having an alibi, he confessed to the crime. Moreover, he not only confessed, but was ready to repeat the testimony over and over again, which became more and more detailed, absurd and contradictory. And although all of the above clearly indicated the unfair work of the investigators, the farmer's son was still convicted and sentenced to death.

Experiments show that about 40 percent of the details of an event change in our memory during the first year, and after three years this value reaches 50 percent. At the same time, it is not so important how "emotional" these events are: the results are true for serious incidents, such as the 9/11 attacks, and for more everyday situations.

This is because our memories are like Wikipedia pages that can be edited and expanded over time. This is partly due to the fact that human memory is a complex multi-level system that stores an incredible amount of information about places, times and situations. And when some fragments of what happened fall out of memory, the brain complements the episode of our biography with logical details that fit a particular situation.

This phenomenon is well described by the Deese-Roediger-McDermott (DRM) paradigm. Despite the complex name, it is quite simple and is often used to study false memories. Psychologists give people a list of related words, such as bed, sleep, sleep, fatigue, yawn, and after a while they ask them to remember them. Typically, subjects recall words related to the same topic - such as a pillow or snoring - but which were not on the original list.

By the way, this partly explains the emergence of "deja vu" - a state when, being in a new place or situation for us, we feel that once this has already happened to us.

Leading questions are especially dangerous to memories. When re-referring to past experience, a person transfers his memory into a labile, that is, a plastic state, and it is at this moment that it turns out to be most vulnerable.

By asking the other person closed-ended questions during his story (such as "Was there a lot of smoke during the fire?") Or, even worse, leading questions ("She was blonde, right?"), You can transform his memories, and then they are reconsolidated, or it is easier to say "overwrite", in a distorted form.

Today psychologists are actively studying this mechanism, since it has direct practical significance for the judicial system. They find more and more evidence that eyewitness testimony obtained during interrogation cannot always be a reliable basis for an accusation.

At the same time, the opinion prevails in society that the memories obtained in a stressful situation, or the so-called "flashbulb memories", are the clearest and most reliable. This is partly due to the fact that people are sincerely convinced that they are telling the truth when they share such memories, and this confidence does not disappear anywhere, even if the story is overgrown with new false details.

That is why experts advise in everyday life either to listen to the interlocutor in silence, or, if necessary, ask him general questions ("Can you tell us more?" Or "Do you remember anything else?").

Super ability to forget

Human memory is a mechanism of adaptation to the environment. If humans could not store memories, they would be much less likely to survive in the wild. Then why is such an important tool so imperfect, you ask? There are several possible explanations at once.

In 1995, psychologists Charles Brainerd and Valerie Reyna proposed the "fuzzy trace theory", in which they divided human memory into "literal" (verbatim) and "meaningful" (gist). Literal memory stores vivid, detailed memories, while meaningful memory stores vague ideas about past events.

Reyna notes that the older a person gets, the more he tends to rely on meaningful memory. She explains this by the fact that we may not need many important memories right away: for example, a student who successfully passes an exam needs to remember the material learned in the next semester and in his future professional life.

In this case, it is important not only to remember information for a certain day or week, but also to preserve it for a long period of time, and meaningful memory in such a situation plays a more important role than literal memory.

The fuzzy footprint theory correctly predicts the marked effect of age on our memory, called the "reverse development effect."As a person gets older, not only his literal memory improves, but also his meaningful memory. At first glance, this sounds illogical, but in fact it is quite understandable.

In practice, the simultaneous development of literal and meaningful memory means that an adult is more likely to remember a list of words, but also more likely to add a meaningful word to it that was not originally in it. In children, however, literal memory will be, albeit not so capacious, but more accurate - it is less inclined to insert "gag".

It turns out that with age, we are increasingly trying to find meaning in what is happening. From an evolutionary perspective, this may be more beneficial for adapting to the environment and making safe decisions.

This thesis is well illustrated by studies of memory in rodents. Thus, in one experiment, rats were placed in a box and exposed to a mild electric shock, in response to which the animals froze in place (a typical manifestation of fear in rodents).

Several days after the rats learned to associate the connection between the environment and the electrical shock, they were placed either back in the same box or in a new one. It turned out that the ability to distinguish between contexts deteriorates over time: if two weeks after training the rats in the new environment freeze less often than in the old one, then by the 36th day the indicators were compared.

In other words, when the animals were in a different box, their old memories were likely to be activated and "infect" new ones, causing the rodents to trigger a false alarm in a safe environment.

Other researchers speculate that memory variability may be related in some way to our ability to envision the future. For example, Stephen Dewhurst's group has shown that when people are asked to imagine an upcoming event, such as preparing for a vacation, they often have false memories.

This means that the same processes that cause our brains to add false details to memories can theoretically help us model a possible future, look for solutions to potential problems, and predict the development of critical situations.

In addition, neuroscientists have also observed the connection between memory in general (not just false memory) and imagination. For example, Donna Rose Addis's group, using an MRI scanner, analyzed the brain activity of the subjects, who remembered the events of the past, then imagined the future.

It turned out that there is an amazing similarity between memories and imagination - during both processes, similar parts of the brain are activated.

If the hypotheses of scientists are correct, then the plasticity of our memory is not a flaw at all, but a superpower that allows us as a species to be more adaptive. And who knows how we will be able to use this superpower in the future: perhaps, in a few decades, psychologists will learn to control memories in order to help patients cope with severe mental conditions.