Behind the witness stand, you are talking to the judge. You claim to have seen this woman leaving the bank armed. You remember she was wearing a jeans and black shoes. She was around 1m70, had blue eyes and brown hair. This could partly prove the woman’s guilt and send her to jail. But can we really trust your testimony? Is your memory of the crime representative of reality? Let’s see how memories are formed and how they sometimes twist into false memories.
How do we recall a memory?
To remember an event you must first experience it (really!). If we try, for example, to remember a phone number, we follow these steps:
The recovery-reconsolidation loop is done each time a memory is brought back to short-term memory. So, every time you remember something, it’s an opportunity to distort it and reconsolidate it that way. The more frequently you bring back a memory, the more it risks being distorted in false memories.
A memory can be modified by new information. To illustrate that, researchers showed a picture of two cars having an accident to participants.
Then, they divide the participants into two groups and ask each of them a slightly different question.
Participants answering the quesition with the word hit estimated the speed of the cars at 34mph and those answering the quesition with the word smashed thought the cars were driving at 41mph! A week later, they saw the same participants again and asked them:
A larger proportion of the smashed condition group remembered seeing broken glass in the image even if, in reality, there was none. So, we notice that the intensity of the word used to describe the scene after the memory was first formed affect the way we remember it. Indeed, false memories can come from an interaction between new information and the initial memory.
You may have very vivid memories of events that happened a very long time ago. On the other hand, some of your childhood memories are probably modified, and maybe some of them just never happened.
A researcher tried to create memories of childhood during an experiment. He showed the participants real photos of them as a child provided by their parents and the participant had to describe the event related to them. Among these photos, one was fake: a Photoshop of the participant in a hot air balloon. The participants, seeing the photo, had trouble remembering the event since they never experienced it. The researcher then asked them to close their eyes and try to imagine the event in their head. After a moment of reflection, 35% of them said they remembered the event and, after two other interviews like this one, half of the participants could describe the event with details. This study is an impressive demonstration of the creation of false memories from scratch.
Who told me that?
Sometimes we can remember information well, but we forget where it came from. We might, for example, think our mother told us a story, but it was a colleague. The source of the information may seem like a small detail, but in certain situations, confusing the origin of our knowledge can affect our perception of reality.
To better understand this phenomenon, participants were asked to read a list of strangers names. Then, they answer a survey, indicating for each name whether or not it’s a celebrity. Few mistakes are made.
To another group, after they have read the strangers names, they leave. The next day, they return to identify the celebrity names from the list. Compared to the first group, waiting for a day increased the error rate. It is believed that the error comes from the source, because these participants thought the name was familiar to them because it’s a celebrity, but in reality it was because they had read this name the day before.
The illusory truth effect is when the information flow affects our judgment. Information to which we are often exposed may seem truer. This information to which one is very exposed can explain in some cases the modification of memories.
From canoe to boat
To observe the effect of our culture on information recall, Canadian Indian folklore legend was read by people from England. They were asked at increasingly longer intervals to tell the legend according to what they remembered. The latest version contained a lot of English references replacing Canadian cultural elements. For example the legend included people in a canoe, and the British people remembered that they were in a boat.
The power of expectations
We often draw conclusions without having all the necessary informations. Indeed, we base ourselves on our experience to deduce things from a limited source of informations. If we ask someone to read sentences, and then we provide them with the same sentences without the verbs, they replace verbs according to the inferences they have made. For example, if they are asked to read: ” The karateka hit the board. ” among several sentences and then they asked to find the verb: ” The karateka has _____the board ”, they might not remember the verb right.
Most people will say the karateka broke the board, since we made the link that, in our experience, a karateka is hitting a board to break it. However, all we know is that he hit the board. By making this kind of inference in our daily lives, we can create false memories since we have misinterpreted what we perceived.
A schema is the idea that we have of a concept following an accumulation of experience in relation to it. For example, my school diagram contains notebooks, the bell rigning at break time, desks, clocks, etc. We all have an image comming to our mind when we think of school and that creates expectations about the concept.
Researchers have studied the impact of schemas on our memory of events. They made participants wait for 30 seconds in an office, telling them that they wanted to make sure the other participant had finished. It was a pretext for the person to be in the office without paying abnormal attention to what was in the room. They were then taken to another room and asked to name the objects that were in the office. It was observed that several objects that were not in that room were named since they are part of the usual schema of an office. In fact, 30% of participants said they remember seeing books when there was not one. These patterns therefore affect our memories by modifying certain details which compose them according to what we associate them with over time.
We rely a lot on our memory to make decisions even if, in certain situations, they can have a crucial importance on our life or that of others. A convinced eyewitness may therefore think of recalling some details, but in reality they could have created memories from police and lawyers questions, the context, our knowledge, our culture and our way of perceiving the world.
English isn’t my first language so there might be some mistakes. If you want, let me know in the comments bellow if you found any so I can fix them. Thank you!
Goldstein, E. B. (2018). Cognitive Psychology (5e éd.). Cengage.
Spinney, L. (7 mars 2017). How Facebook, fake news and friends are warping your memory. (545,7644), International weekly journal of science. https://www.nature.com/news/how-facebook-fake-news-and-friends-are-warping-your-memory-1.21596?WT.mc_id=TWT_NatureNews