Deepfakes may soon start filling our brains with false memories

Do you remember the remake of The Matrix where Will Smith starred as Neo? Or the remake of The Shining with Brad Pritt as Jack and Angelina Jolie as Shelley? Or when Charlize Theron starred in Captain Marvel, or Chris Pratt in Indiana Jones?

If you don’t, you’re not going mad: these movies never existed. But if you’re scratching your head thinking “wait, but I swear I remember watching Brad Pitt smash down a hotel door with an axe!”, you’re not going mad either.

Last month, researchers at University College Cork in Ireland published findings from their research into false memories, which found that reading text descriptions of nonexistent films could prompt participants to falsely remember watching or hearing about the films. Interestingly, the study also found that watching deepfake videos produced a similar effect, and also resulted in participants falsely remembering nonexistent films.

Dr Gillian Murphy, the study’s lead author, showed over 400 undergraduate students both deepfake videos and short text descriptions of made-up movie remakes – like a Shining remake starring Brad Pitt and a Captain Marvel remake starring Charlize Theron. The researchers did not immediately tell participants that the films were not authentic, in order to better understand how deepfakes could impact a person’s memory. They also included real film remakes in the mix for comparative purposes.

Each participant was shown text descriptions of three films, and deepfake videos plus text for another three. Each participant was shown four real films – including actual remakes of Carrie, Total Recall, and Charlie and the Chocolate Factory – and two fake films in a random order. Then researchers asked if participants had seen or heard of the fake film remakes before. Any participants who claimed to have previously seen the entire film, seen clips or trailers or heard of the film were categorised as having a false memory.

Amazingly, 75 per cent of participants who saw a deepfake video of Charlize Theron starring in Captain Marvel falsely remembered its existence. 40 per cent of viewers falsely remembered the other three film remakes of The Shining, The Matrix, and Indiana Jones. Bizarrely, people who falsely remembered these films existing sometimes even remembered the fake film remakes more fondly than the original films. For example, 41 per cent of people described the nonexistent Captain Marvel starring Theron as being better than the original with Brie Larson, and 13 per cent described Pratt’s Indiana Jones as better than the original films starring Harrison Ford.

False memories are a relatively common psychological phenomenon where people remember things which never happened. It’s what’s behind the ‘Mandela effect’, where large groups of people collectively share a false memory – the name of the phenomenon was coined after thousands of people reported detailed memories of Nelson Mandela dying in prison in the 1980s, in spite of the fact that Mandela served as President of South African from 1994 to 1999 and died in 2013. Other popular examples of the Mandela effect are the confusion surrounding the title of the childrens’ book The Berenstain Bears, as many people believed it was spelled ‘Berenstein’, and the existence of a movie called Shazaam! starring Sinbad as a genie (even though there’s almost no evidence to suggest such a film was made). 

“Our memories don’t work like video cameras – they have not evolved to perfectly preserve memories of exactly what happened,” Murphy explains. “Instead, our memories are what we call ‘reconstructive’, where everytime we recall something we build the memory in our minds. In this building process, we sometimes make errors by forgetting a piece or the event or adding in something that wasn’t there originally. While this can mean our memories are sometimes inaccurate, it often serves us very well as we can update our memories to reflect things we have learned.”

Given that our memories aren’t as reliable as we might think, should we be worried about deepfakes messing with our minds? There are so many deepfakes floating around the internet at this point – could we get to a stage where huge groups of people falsely remember Donald Trump being pursued by police and arrested or Zelensky surrendering to Putin?

The answer is far from straightforward. The good(ish) news is that deepfakes aren’t uniquely powerful when it comes to messing with people’s memories – but on the other hand, plain text alone was enough to plant false memories in people’s heads. “We found that simple text was just as effective as the realistic deepfakes in convincing people that these fake films existed,” Murphy tells Dazed. After reading these text descriptions, 70 per cent of people had false memories of a Captain Marvel remake, while 40 per cent falsely recalled the existence of remakes of The Shining, The Matrix, and Indiana Jones (the same proportion of people who had a false memory after watching deepfake videos of these other three films).

Murphy stresses that while the “explosion of non-consensual deepfake pornography” demonstrates that deepfakes evidently do have the power to cause immense harm, as this is a new area of research, it’s hard to draw conclusions on just how much we should worry about deepfakes. “The current evidence suggests they’re not uniquely powerful in terms of distorting memory, but they’re just as effective as the written word, which is a powerful vehicle for misinformation as we know,” she continues. “So our study doesn’t claim that that deepfakes can’t distort our memories, just that they’re not any more effective than existing methods.”

Join Dazed Club and be part of our world! You get exclusive access to events, parties, festivals and our editors, as well as a free subscription to Dazed for a year. Join for £5/month today.