Seeing is believing. And because of this fact, we’re screwed.

Due to advances in artificial intelligence, it’s now possible to convincingly map anyone’s face onto the body of another person in a video.

In April, BuzzFeed published a demonstration featuring the actor and director Jordan Peele. Using FakeApp, the same tool used in the celebrity face-swapping porn, BuzzFeed took an old video of President Obama and swapped in Peele’s mouth as he performed an impression of Obama. It’s a creepily powerful PSA with a forceful message: “This is a dangerous time. Moving forward, we need to be more vigilant with what we trust from the internet.”

You won't believe what Obama says in this video pic.twitter.com/n2KloCdF2G — BuzzFeed (@BuzzFeed) April 17, 2018

As Vox’s Aja Romano has explained, this technique is becoming more common in pornography: An actress’s head can be mapped onto a porn actress’s body. These “deepfakes” can be generated with free software, and they’re different from the photoshopping of the past. This is live action — and uncannily real.

And the technology is evolving quickly. In the video above, Peele is essentially acting — via face-swapping software — as a puppeteer for Obama’s face. Not too long ago, this type of software was limited to transferring simple facial expressions and mouth movements from an actor to a fake video. Now, as will be put on display at an motion graphics industry conference next month, the software can account for wide-ranging head and eye movements without much obvious distortion.

Combine fake audio with fake video and it’s not hard to imagine a future where forged videos are maddeningly hard to distinguish from the truth. Or a future where a fake video of a president incites a riot or fells the market. “We’re not so far from the collapse of reality,” as Franklin Foer summed up at the Atlantic.

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But I fear it’s not just our present and future reality that could collapse; it’s also our past. Fake media could manipulate what we remember, effectively altering the past by seeding the population with false memories.

“The potential for abuse is so severe,” says Elizabeth Loftus at the University of California Irvine, who pioneered much of the research in false memory formation in the 1990s. “Once you expose people to such a powerful visual presentation, how do they get it out of their minds?”

We don’t have psychological studies directly looking at the ability of AI-faked video to implant false memories. But researchers have been studying the malleability of our memories for decades.

Here’s what they know: The human mind is incredibly susceptible to forming false memories. And that tendency can be kicked into overdrive on the internet, where false ideas spread like viruses among like-minded people. Which means the AI-enhanced forgeries on the horizon will only make planting false memories even easier.

How a faked photo rewrites our memory

Do you remember this image? It’s of former President Barack Obama shaking hands with Mahmoud Ahmadinejad, the former president of Iran.

I hope you do not remember this photo, because it never happened. It’s photoshopped.

Yet in 2010, when Slate asked about 1,000 of its readers whether they remembered seeing the photo, around 21 percent said yes. Another 25 percent said they remembered that the event happened but couldn’t recall specifically seeing the photo.

Slate also gave its readers some space to write out their feelings about the photo. “I thought Obama was correct, snubbing Ahmadinejad so blatantly would have been a mistake,” one reader wrote, recalling a feeling that certainly never occurred to him.

Inspired by Loftus’s work, Slate’s William Saletan had created a quiz that presented readers with a mix of photos from real events plus one of five randomly selected fake events.

One of the fabricated photos showed Sen. Joseph Lieberman voting “guilty” during President Bill Clinton’s impeachment proceedings (Lieberman voted “not guilty”). Another showed President Bush on vacation with baseball player Roger Clemens during the Hurricane Katrina disaster. Bush spent a chunk of time after Katrina hit at his ranch in Crawford, Texas — but not with any baseball players.

Each faked photo provoked fake memories in at least 15 percent of the respondents. And overall, 50 percent of participants reported they believed the event depicted in the false photo happened. Slate’s project drew the attention of Steven Frenda, a Cal State Los Angeles psychologist who often collaborates with Loftus. Frenda and colleagues took Slate’s data and analyzed it further.

Here’s what they found: People were more likely to say they remember a faked photo when it fit with their political worldview.

“Conservatives were more inclined to believe that Obama had greeted this hostile foreign leader,” Frenda says. And liberals were more likely to recall Bush cavorting with Clemons. “When people encounter events that are complimentary with their political beliefs or preferences, they’re more likely to mistakenly believe those events really happened,” he says.

Think about what this means. Doctored photos can change the way we remember history. And not just our memories for facts, but possibly even our recollections of what we saw with our own eyes. It means that bad actors may be able to prey on our political biases to change our understanding of world events. And remember, these were Slate readers, who are presumably people who like to keep up with current events.

Even if people were lying on the survey in order to seem intelligent, the photos could still implant itself in memory. “When people lie or stretch the truth, sometimes that itself distorts their memory,” Frenda says. “So they will sometimes incorporate their lies or exaggerations into what it is to what they think they genuinely remember.”

Frenda and his colleagues published this conclusion in 2013 in the Journal of Experimental Social Psychology. And this topic — false memories for political events — hasn’t been directly followed up in the academic literature (though a 2010 paper did find similar results). But this finding checks out with what we know about political psychology: We’re more likely to remember facts that support our teams.

“Back in 2013,” Frenda says, “the potential for misusing [or] digitally doctoring images, and now videos,” was not that hot of a topic. Now, “there are a lot of things to worry about.” And there are reasons to believe that the false videos will be an even more powerful way to change how we remember the past.

Why we form false memories, and how

Human memory does not function like a videotape or a digital recording. When we remember, we don’t wind back our minds to a moment in time and relive that exact moment.

Instead, memory is constructed.

This is a tricky thing to understand. When we call on a memory, we have to piece it back together from disparate pieces of information that exist in our minds. Some of what ends up in our recollection is the truth. But there’s a laziness to our recollections. In reconstructing our memories, our brains often grab the easiest bit of information to recall. And information that we’ve learned since the event will be added to fill in memory gaps.

Our memory is not like a videotape. A more helpful metaphor is that it’s like a video editor working on a millisecond deadline. In its mad rush, the editor splices in bits of truth with whatever filler is handy. And what’s handy is often our biases, or new information altogether.

That’s why mere suggestions like being told cars “smashed” instead of “hit” after viewing video of a car accident will lead people to recall the accident being more severe than it was. Or why our memories for feelings of significant historical events — like the O.J. Simpson murder trial — tend to reflect what we think today rather than what we felt back then. Just the process of remembering one thing can cause us to forget another.

Familiarity is critical too. The more familiar we are with an idea, the more likely it is to get inserted into our memories as the truth. Studies find the more often a lie is repeated, the more likely it is to be misremembered. And we tend to forget the source of a piece of information, Frenda explains. After seeing a falsified story from a not-credible news outlet online, it’s possible to later “misremember that you actually saw it on CNN,” he says.

We can misremember whole events that never happened

False memories don’t just fudge the fine details. It’s also possible to falsely remember whole events.

That happened in the Slate survey. But researchers have also found that it can happen in studies where the false information is from a trusted source. We trust family, and faked letters from relatives can lead people to believe they were once lost in a mall as a child or that they committed a crime when they were younger. And we trust photos: Experiments that use altered photos to implant memories tend to be more effective than those that do not.

Here’s what’s really frustrating: We’re confident in our misrememberings. “Once we’ve updated memories, we don’t remember that we’ve done that,” Linda Levine, a University of California, Irvine psychologist who studies memory and emotion. “We have the illusion that we remember things as they happened.”

We’re biased for a sense of continuity, despite the fact that our memories are changing all the time. The video editor in our brains seals the seams up quietly.

That’s true for even the most intense events in memory. In the days after 9/11, psychological researchers interviewed thousands of people across the country, asking them simple questions like, “Where were you when it happened?” and then followed up over 10 years. Even as the participants’ memories for the day shifted, as the details they remembered changed, they still remained extremely confident they were remembering the truth.

Today, the scientific debate on this topic is around how prevalent false memory formation is (critics charge that reports of fully implanting a false childhood memory are overinflated), and how to more precisely define memory.

And researchers propose a few reasons why evolution has favored us to have such malleable memories. One is that it allows us to be creative. We can imagine what the future might look like by merging memories with new information. Another is that saves us effort. We don’t need to remember every detail in our lives.

A third hypothesis highlights the danger of false memories in these polarized times: They help us form a cohesive sense of reality with our groups.

Bill Hirst studies collective memory at the New School. His work explains how the process of talking to one another causes us to selectively remember, forget, and create a false collective narrative.

“All of these [memory] distortions allow us to craft a shared representation of the past,” Hirst says. “And because you and I both have a shared representation of the past, it leads to a common view that reinforces a collective identity.”

Social media is fertile ground for us to acquire truly bizarre false memories. Consider the case of the Shazaam truthers.

We also have the power to influence each other’s memories and construct new versions of reality as we go.

In 2016, the New Statesman magazine published a feature about a community of Reddit users who are fans of a movie from the 1990s starring the comedian Sinbad (remember him?). The movie is called Shazaam, and Sinbad plays a bumbling genie who adventures with two small kids.

The piece, however, was not the typical essay on ’90s pop culture nostalgia. It turns out that the movie Shazaam never existed, and yet many of the people New Statesmen writer Amelia Tait spoke to could not be convinced otherwise. And they were genuinely upset the movie didn’t exist. “It feels like a part of my childhood has now been stolen from me,” one believer told her. And these people insist they’re not simply misremembering the movie Kazaam, which starred Shaquille O’Neal in the role of a genie. (This collective misremembering is sometimes called the “Mandela Effect,” named after the odd phenomenon of people swearing they heard Nelson Mandela died in the 1980s. He died in 2013.)

Here’s one possible reason these redditors believed in the movie so intensely: the Reddit forum itself. Social media brought together like-minded people. “Any type of corroboration is going to strengthen your memory for something, whether it’s true or not, and your confidence in your memory,” Frenda says. These Shazaam truthers were all riffing off one another, giving each other subtle suggestions to form a false narrative that exists in their minds.

It’s a clear of example of how, in an ever-polarizing world, we’re increasingly telling different stories from our neighbors because we’re plugged into separate feeds of information.

Fake video is even scarier than doctored photos

Let’s put this all together. False memories fester when they make sense to our political worldview, when it’s familiar and repeated ad nauseam, when we trust the source of the information, and when this information is corroborated, shared, and discussed by like-minded people.

Where else do all these things happen? Social media. Fake stories tend to move more quickly to people on these platforms than the truth, fueled by surprise and bias.

And so what happens when doctored audio and video get added to the mix? (Shudders.)

Most of the studies on false memories were conducted with faked photos or written documents. Since it’s so new, no one has studied the effect of deepfake video yet, but Levine and Loftus suspect it will be even more compelling. “Here that person is, in the midst of that situation, saying and doing these things,” Levine said. If the video is seamless, that’s going to be convincing. And “it’s legitimately worrisome,” she says.

Loftus agrees: “Having the [faked] video, and the richness of it, is just going to exacerbate the false memory potential,” she says.

The “collapse of reality” isn’t predestined. But there’s good reason to feel uneasy.

We do not yet know how to inoculate people against forming false memories. In fact, it doesn’t seem like any human is immune to forming them. And all around us, the seeds of false reminiscence are being sewn.

A December 2017 poll found 44 percent of Republicans believed President Trump repealed Obamacare. That might be because the legislation was confusing to follow as it ping-ponged through Congress. Or because there’s some truth in that parts of the health care law have been weakened. Or because Republicans increasingly don’t trust the media. Whatever the reason, know this: The repeal didn’t happen.

But what happens when, in the future, there’s a video of Trump signing a fake Obamacare fake repeal? Or a fake clip of a CNN anchor announcing the breaking news of the repeal? And these fake clips prove impossible to eliminate from the web?

The imaginary dystopian scenarios are endless. Loftus has one of her own: a particularly corrupt police force doctoring a video of a suspect confessing to a crime. In those scenarios, she says, even the suspect might believe it. “I wish I could say something optimistic,” she says.

But it’s still possible that our worst fears about this kind of “collapse of reality,” as Foer put it, may not come to pass.

It’s possible fake video and audio will not become sophisticated enough to have an impact. Perhaps people can learn to spot it. Or maybe someone can design algorithms to squash it. Perhaps the tech giants will become vigilant in banning these forgeries. Or maybe we’ll grow so accustomed to lies that we won’t believe anything — a concept technologist Aviv Ovadya described as “reality apathy” in an interview with BuzzFeed.

We can hope that as much as our memories of the past diverge, there will always be historians getting the permanent record down straight.

But I worry that as our country and our media fracture politically, the divergence in our memories and understanding of facts is also going to grow worse. In 40 years, will fewer of us agree on the facts of history?

Further reading on the end of reality

Not terrified enough? BuzzFeed’s Charlie Warzel outlines what the disinformation campaigns of the future could look like when they’re fueled by artificial intelligence.

Vox’s Aja Romano explained the rise of deepfakes, and the community around them on Reddit. (Today, Explained also produced a podcast episode on this topic.)

Do you have a memory that you later found out wasn’t true or accurate?

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