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Anyone who believes that our memory records our lives one-to-one like a camera is mistaken. Not only do we forget many things – the brain also invents new things. Where there are gaps in knowledge, it adds memories. And these are often not our own, but instead come from stories, photos or films, for example.
The American psychologist Elizabeth Loftus has shown how easy it is to activate this mechanism. In an experiment, she wanted to make test subjects believe that they had been lost in a department store as a child – although this was never actually the case. A family member who had previously been involved told the test subjects that they had lost their way at the time and had been brought back by an elderly lady. 29 percent of the test subjects then really believed that they had experienced this as a child.
The brain sifts out
Such “false memories” are not a psychological problem, but an everyday phenomenon. If our brain had to memorize everything we experience every day, it would soon be overloaded. That’s why it only remembers the worst, so to speak – which can be more or less far removed from reality.
Back in the 1950s, the American psychologist James Deese made an interesting discovery: he presented test subjects with a list of terms that they had to memorize. This list contained terms such as prick, syringe or injection, but not the word needle. Nevertheless, the test subjects later stated that they had also seen this word on the list. Apparently, as Deese noted, our memory tends to memory tends to fill gaps in our knowledge with seemingly logical additions. This is how “false memories” are created: although an event never happened, in retrospect it seems as if we had experienced it – because it logically fits into our memory context.
Childhood memories are particularly susceptible to manipulation
Elizabeth Loftus has also long been investigating how our memory can deceive us. In an experiment, she placed test subjects photos in which they were shown as children in a hot air balloon. However, the images were montages; in reality, the test subjects had never flown in a hot air balloon.
Nevertheless, half of the test subjects later believed that they had really experienced the flight. All these attempts show: Simply believing that you have experienced something in particular does not mean that it actually happened.
The brain plays puzzle
“False memories are not created intentionally. Our brain can only remember a fraction of the wealth of information that we are bombarded with every day. This creates gaps in knowledge. If new information is added that fits in with existing knowledge, the memory automatically places it there. As a result, we often no longer know whether we only read or heard about events that happened a long time ago or whether we actually experienced them ourselves.
The situation in which the knowledge is called up can also change it. Many people embellish a story from their youth a little to impress their counterpart. If they tell this story over and over again, at some point they themselves believe that this is how it all happened.
Even witnesses’ memories are often not objective
False memories are particularly problematic when it comes to witness statements. Time and again, cases have come to light where crime victims have identified innocent people as the perpetrators in line-ups. The victims see a person who looks like the perpetrator and are suddenly sure that it was him.
Your brain has stored some basic information, for example: the perpetrator was tall, dark-haired and had a beard. During a confrontation, these original but often vague memories are mixed with new information. The memory puts them together like pieces of a jigsaw puzzle to form a complete picture, which often has little to do with the truth.
Nine years innocent in prison
In this way, innocent people are repeatedly convicted, as in the case of the American Kirk Bloodsworth. He spent nine years in prison, innocent because eyewitnesses claimed to have recognized him as the murderer of a little girl. Only a DNA analysis revealed that Bloodsworth was innocent.
At the Institute for Advanced Study in the Humanities Essen neuroscientist Hans Joachim Markowitsch and social psychologist Harald Welzer are jointly investigating which factors can influence our memory. Using an MRI scanner, for example, they analyzed brain activity in various test subjects while they recounted experiences from their past.
Social factors also determine how we deal with memories
They discovered that young people remember things differently to older people – and that different memories are important at different ages. Psychological and social factors also obviously had an impact on the subjects’ memory.
We remember experiences that are linked to strong feelings particularly well. Many people can still remember in detail how they met their partner or how much they were affected by a death. Emotional events are classified by the brain as particularly significant and are better anchored in our long-term memory.
Photos displace real memories
Many people are familiar with the phenomenon: the longer ago a vacation was, the more we only remember the pictures we captured on photographic paper. Photos are very practical for the brain: what would normally only be vaguely retained in our memory can be refreshed again and again through the pictures.
However, Elizabeth Loftus’ experiment also showed how deceptive photos can be. In the worst case, they suppress our real memories.
As a result, many people confuse their own memories with scenes they have seen in movies, for example. The example of former US President Ronald Reagan, who talked about war memories during the election campaign, became famous. However, his descriptions showed a striking similarity to the movie “On A Wing And A Prayer”. Obviously, Reagan had mixed his own memories with the film images.
False memories can make history
Historians in particular are familiar with this problem. It is often difficult for them to distinguish whether the person in question really experienced something or is perhaps confusing it with accounts from the media or other people’s stories. It is not uncommon for interviewees to cover up dark parts of their own past – sometimes quite unconsciously. The best example of this is the Third Reich: after its collapse, many people could no longer remember being a Nazi.
Many people repress bad experiences, such as childhood abuse. This is because stress hormones paralyze the receptors in the brain that are responsible for transmitting information from short to long-term memory. However, by means of psychoanalysis or hypnosis, those affected have the opportunity to access the buried memory later on.
Inventing instead of remembering
However, such methods also harbor risks. This is because it can happen that a patient believes they remember abuse that never took place. Misinterpretations of dreams or suggestive questions during therapy, for example, could have this effect, warn opponents of such methods. The US psychologist Elizabeth Loftus, who has repeatedly proven the power of false memories in her experiments, is therefore actively campaigning on behalf of the accused.
The experiments conducted by Elizabeth Loftus and her colleagues show that it is possible to manipulate other people’s memories: It is entirely possible to manipulate other people’s memories. With simple means such as photos, films or credible stories, you can implant false memories in almost anyone. However, this only works to a limited extent. The new information must fit into an existing context so that the brain can create links.
It is usually details that we can no longer remember; a central idea or a rough impression remains. Nevertheless, scientists hope that these findings will enable them to take better action against dementia in the future.
Our brain makes us experts at repression
The best and most comprehensive way we can shape our own memories is in a positive way. Our memory tends to remember pleasant impressions, whereas negative ones fade more easily. This is a very effective mechanism that is also used in psychotherapy: The patient learns to associate their own past with more positive attributes by remembering pleasant experiences. Negative memories are then more easily forgotten. In this way, we can make conscious use of our brain’s strategies.
