False memories: Why our mind reconstructs the past

When we experience something, the brain records the event based on what it receives through the senses. But our memory does not store the event as an exact copy of what happened; rather, it operates as a highly subjective reconstruction. When we recall a memory, the brain rebuilds it from fragments of images, emotions, and our own interpretation of the facts, all altered by the passage of time to create a new version of the event.

“Human memory is not an accurate record of what we saw or what occurred. It does not function like a hard drive. It is a re-creation the mind makes from associations in which, every time you remember something, the neurons revisit that scene,” explains Jesús Molero, director of Balance Psicología. For him, memory is not fixed; each time it is recalled, it is regenerated.

One of the most important factors in the subjectivity of memories is the importance of the emotions, sensations, and meanings we attach to those scenes: “The same event can be remembered very differently depending on how different people felt at the time and the sensations that recalling those images brings them,” says Beatriz Martínez, clinical psychologist and director of Alumbra Psicología Burgos.

Another reason memories get rewritten is that the brain dislikes empty spaces and fills them in with imagination, the psychologist adds. “When we remember something for the first time, we do so much more vividly, for example, a dinner with a friend at a restaurant — the food, the tastes or the conversations. As time passes, some information is lost.”

The hippocampus is the region of the brain responsible for recording images, smells, and details — that is, the more objective information. However, over time, that information fades because the hippocampus cannot retain it indefinitely, while the emotional core remains.

“Memory is not just an objective datum; it is reconstructed and influenced by our personal values, identity, emotions, and tastes,” Martínez explains, using the song Memória by Rosalía as an example to discuss reconstructive memory and the recollections we reimagine according to “the different versions of ourselves that we are over time.”

Molero also highlights the importance of emotions in false memories: “Memory is adaptive. The brain reconstructs them according to what you might need at that moment on an adaptive level. It is trying to take you to that zone of control, protection, and the familiar, as well as to avoid uncertainty and rejection.” The psychologist also explains that memory works through reconsolidation, so each time we remember something, it is altered slightly according to the present situation.

“One of the most powerful memories is the one associated with emotion. Memory works by association. Neurons link moments with images, emotions, and sensations. Emotions, for evolutionary reasons, have the greatest capacity to make us remember,” Molero continues, noting that more emotional people will tend to recall events better overall: “It wouldn’t be far-fetched to say that a person’s emotionality can be a factor that interacts based on the importance of emotions,” he says.

According to a study published in Frontiers in Psychology, emotions can alter which parts of an event a person remembers and which they forget. A report published in Scientific Reports by Nature indicates that the formation of false memories is related to different memory systems: people with stronger semantic memory abilities (related to using prior knowledge and retaining the general idea of what was learned) tend to generate more false memories, while a stronger episodic memory (related to recalling more precisely what one has lived or studied) reduces those errors.

The brain suffers when it encounters gaps in a memory and looks for ways to fill them: “False memories exist. Imagination is a tool that helps us complete missing information, and it is generated in different ways, such as external factors,” the psychologist says. “Sometimes we repeatedly imagine something that happened — like a childhood holiday with your parents you can’t actually remember — but you see images of that place and imagine being there as a child so many times that you end up with a false memory. In search of coherence, the mind mixes what is real with that imagined part,” she argues.

Interference also plays a role in false memories: “If someone has been made to believe something repeatedly, or has been talked to about it a lot or thought about it often, it’s easy over time for them to mix things up and for there to be interference between reality and fiction. But it can also occur between realities — that is, many times we take two experiences and blend them,” Molero says.

Believing that something happened one way when in fact it happened another can harm one’s sense of identity and personal security: “Memories do affect us, but they do not determine us. Our identity is a narrative we have created based on the comments others have made about us. The problem is not having one type of memory or another, but how we relate to them,” Martínez argues. “Fusion is how people can identify with memories or emotions they feel. We cannot change memories, but we can change how we relate to them, which has led to ideas about ourselves.”

“One of the main functions of false memories is to preserve people’s identity, and that is why they are modified according to the context being experienced,” adds Molero. The psychologist also defines the principle of congruence, according to which people want a congruent and stable identity: “A large part of the function of modifying memories is adaptive, and this relates to identity, congruence, and feeling comfortable,” he says.

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