Learn more about breakthroughs pioneered at the University of Chicago

Picture the Monopoly Man. Is he wearing a top hat? How about a monocle? The first is true, but if you imagined the board game mascot with fancy eyewear, you have experienced a false memory. 

False memories are recollections of events that never actually happened or facts that aren’t true. Like computers, our minds are capable of storing and processing massive amounts of information. But they aren’t perfect. Memories can be altered through suggestion and misinformation or become distorted over time. 

Scientists from the University of Chicago’s department of psychology, including Prof. David Gallo and Assoc. Prof. Wilma Bainbridge, study what happens to our brains when false memories form and why we sometimes share false memories—a phenomenon called the Mandela effect. 

Understanding the limits of human memory can inform the way we participate in politics, engage with media, try legal cases, and even think about our own lives.

What is a false memory?

A false memory is a recollection of something that didn’t happen or isn’t true. They can be distorted versions of “true” memories or entirely false. Importantly, false memories aren’t the same as forgetting or lying. 

False memories can rewrite facts or general knowledge, known as semantic memory. False memories can also alter our memories of past events, also known as episodic memory. Perhaps you’re certain you had spaghetti Bolognese for dinner last week, when in fact you had sushi. 

According to UChicago’s Prof. Gallo, who studies episodic memory, there is evidence that these types of memory represent two different systems in the brain, which often interact with each other.

False memories can be a collective experience—often referred to as the Mandela effect. This happens when many people, sometimes around the world, have the same false memory. The term comes from a phenomenon where many people reported remembering that South African President Nelson Mandela died in prison in the 1980s (Mandela died a free man in 2013 at the age of 95). 

Though scholars have pondered the nature of memory since the times of Plato and Aristotle, the experimental study of false memories—especially how they affect the brain—began in the 1970s.

What causes false memories?

Scientists aren’t certain what causes false memories, but factors like time, suggestion, misinformation and closely associated images or words can contribute to forming false memories. Here are a few theories:

  • Your brain fills in the blanks
    False memories sometimes happen because, like a zip drive, your brain tries to save space and energy. “We don't save everything we see in memory,” said UChicago’s Assoc. Prof. Wilma Bainbridge. “We have to do some time-saving, efficient tricks.”

    Instead of mentally recording every item in a living room, for instance, your memory might fill in a coffee table or lamp because those items make sense for how your brain conceives of a living room. 

    Since the 1970s, psychologists have investigated how associations and suggestions can implant false memories. 

    For example, to study false memories psychologists will often use a type of experiment called the Deese-Roediger-McDermott (DRM) paradigm. To “lure” participants into a false memory, researchers will create a list of closely associated words: dream, bed, awake, rest. When researchers ask people to recall the list, they often add “sleep,” though the word was never on the original list. 

    “Everybody makes that association because you basically inferred it,” said Gallo. “It's another way where your own mind mentally activates its own misinformation.”
  • Familiarity or repetition
    Frequent repetition can influence how much you like something—a phenomenon called the mere exposure effect. That’s one reason why you might end up loving a pop song after you’ve heard it a million times. 

    Scientists also think repetition may influence whether you believe something is true or not. Politicians and advertisers often take advantage of this phenomenon, called the illusory truth effect. After a while, a statement that’s repeated over and over can start to “feel” true, even if it isn’t. 
  • Age, stress, lack of sleep, or impairment
    Research has shown that certain factors such as age, stress, lack of sleep, and drug and alcohol use can increase the likelihood of having false memories. 

    However, there are important exceptions. For example, there’s evidence that having more false memories as you get older is not inevitable and taking THC (the main psychoactive ingredient in cannabis) can actually reduce false memories by making it harder for your brain to form close associations.
  • Some objects or faces are more memorable
    At UChicago’s Brain Bridge Lab, Bainbridge studies memorability, or how easy it is to remember images, objects and faces. 

    For example, in a study conducted at the Art Institute of Chicago, researchers found that some artworks are consistently more memorable (and forgettable) than others—a finding duplicated by their machine learning model, ResMem, designed to predict the memorability of images.

    Bainbridge has also found a connection between how memorable something or someone is and false memory. 

    “What we have found is that there are some images or faces that just cause a lot of false memories,” Bainbridge said. (If people frequently tell you that you look familiar, you may have a Mandela effect face.)

    Though scientists don’t know the cause, they have found that friendlier, more attractive faces tend to cause more false memories. Fear not, false memory-inducing face havers! 
An infographic showing Memorable paintings vs Forgettable paintings
Examples of the most memorable and forgettable pieces from the Art Institute of Chicago (1 means everyone remembered an image, 0 means no one remembered it). Memory experiment participants were tested online and at the museum. These findings matched the predictions of ResMem, the Brain Bridge Lab’s deep learning neural network.
Chart courtesy of the Brain Bridge Lab

What is the Mandela effect?

The Mandela effect is an internet-era phenomenon that describes when many people share the same false memory of names, events or images. The term was first coined by paranormal researcher Fiona Broome in 2009 to describe her vivid false memories of Nelson Mandela dying in prison in the 1980s, though he passed away in 2013. When she shared her experiences online, others recounted similar details

A still-frame from Star Wars that shows C3P0's silver leg
The Star Wars character C-3P0 has a silver leg, not two gold ones. Click here to expand.

Since then, the term Mandela effect has been attributed to the collective misremembering of brand logos, pop culture artifacts and even the spelling of a beloved family of fictional bears (the children’s books are about the Berenstain Bears, not the commonly misremembered Berenstein Bears.)

For example, one of the most famous lines from the Star Wars films is a false memory; Darth Vader never says, “Luke, I am your father” in The Empire Strikes Back (1980). Instead, he says: “No, I am your father.” 

These examples have been interpreted as evidence for everything from parallel universes to time travel. However, scholars have begun studying how the effect could shed light on how false memories form. 

A screenshot of Darth Vader from the film, Star Wars
A well-known example of the Mandela effect is the frequently misquoted line from the Star Wars franchise, "Luke, I am your father," which is actually "No, I am your father."

What is the visual Mandela effect?

The visual Mandela effect refers specifically to shared false visual memories of pop culture characters or logos. Despite repeated exposure to official brand logos, people reportedly remember the same incorrect version of certain images. For example, many falsely remember the Monopoly Man sporting a monocle or the Fruit of the Loom logo having a cornucopia. 

In a pioneering 2022 study on the visual Mandela effect, a team led by Bainbridge asked participants to draw a few of these characters from memory. They found people consistently replicated the same errors—like drawing the Pokémon character Pikachu with a black-tipped tail, despite the character never appearing that way. 

A series of drawings depicting people's false memories
Study participants drew logos from memory (b) and after viewing the images for a few seconds (c). Both contained visual Mandela effect errors.
Chart courtesy of the Brain Bridge Lab

Scientists are still studying why certain images cause the visual Mandela effect, but Bainbridge theorizes that there are inherent qualities in these images that cause false memories. One theory supports the idea that close associations and patterns can trick our brains. For example, we may remember the Monopoly Man incorrectly because a suit, cane and monocle are part of our cultural stereotype of what a rich person looks like. 

According to Bainbridge, these studies confirm what the internet has theorized for a long time: we sometimes share false memories.

“The visual Mandela effect is a great example of how the internet and social media allow us to discover these new psychological phenomena,” Bainbridge said.

How do false memories affect our lives?

False memories can have real-world consequences, from misidentifying people in a lineup to spreading misinformation. Studies have shown that relying on memory and eyewitness testimony in legal trials can lead to false identifications and wrongful convictions

In the 1990s, a heated debate—sometimes called the “memory wars”—arose between psychologists and therapists around the nature of false and repressed memories. This period saw a sharp uptick of reports from therapists who claimed their adult patients had recovered buried memories of childhood sexual abuse. Some of these reports led to legal trials. Memory researchers like Elizabeth Loftus vehemently argued that certain therapy techniques like hypnosis were not uncovering repressed memories, but instead planting false ones. Others believed that skepticism around recovered repressed memories discredited and further traumatized victims of abuse.

Who is at risk of having false memories?

Though most people will experience false memories during their lifetime, research has shown that certain factors such as age, stress, lack of sleep, and drug and alcohol use can increase the likelihood of having false memories. 

According to Gallo, who studies aging and memory, false memories and true memories light up the same regions of the brain including the hippocampus—the area involved in forming associations.

“Both true memories and false memories will tend to activate the hippocampus,” Gallo said. “Part of the reason is that when we have vivid false memories, oftentimes, we're remembering some bits and pieces or details of something that actually did happen.”

As we age, the hippocampus starts to work less effectively. Same goes for the prefrontal cortex, which monitors and edits memories

“When you see those kinds of changes in the aging brain, that's when you start to see that people get even more susceptible to these kinds of memory distortions,” Gallo said.

However, research also has shown that increased false memory with aging is not inevitable, but depends how well your brain ages and the difficulty of the material. 

How do I recognize a false memory? And can I prevent myself from falsely remembering something?

You probably can’t recognize a false memory. People tend to feel less certain about memories that aren’t accurate, but that confidence level can change if a false memory is repeated or reinforced. In general, it’s best not to rely solely on memory. Writing things down or looking at personal photos and videos can help solidify genuine memories. 

While you likely can’t prevent false memories, scientists say the most important thing to recognize is that our memories are fallible and prone to bias—even ones about the news or world events. You’re more likely to remember things in ways that benefit you or reinforce ideas you already believe.

Gallo says that even two sports fans watching the same game will remember it differently. “There's a lot of research to show that even if people are doing their best to perceive and remember the game accurately, they are biased to remember that the calls were worse against their team,” he said.

In an era rife with misinformation, Gallo cautions everyone to check their sources.

“Do you think something sounds accurate because you read it a lot, or because you actually have multiple pieces of evidence for it?” Gallo asked. “That's what I worry about: how basic repetition, familiarity and fluency can distort people's knowledge about the world.”