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In Depth

How fake images change our memory and behaviour

Another reason we’re duped so readily is that we're really bad at telling fake photographs from real ones, says Hany Farid, an image doctoring expert from Dartmouth College in New Hampshire, United States. "It turns out that while the brain and the visual cortex is very good at many things, like face recognition, it is really really bad at analysing lighting and reflections." When presented with doctored images, humans are remarkably inept at telling which ones are fake and which are real. And we're bad in both directions, Farid says, judging fake images to be real, and real ones to be fake.

What's worse is that even when we're told the photographs we've seen are wrong, it doesn't seem to help. One of the first things that fades in our memory is where the information came from. Which is why you probably can’t remember who first told you that joke that you tell all the time, says Wade. "When we're faced with doctored images, even if up front if we know they’re fake, over time we may remember the image but not remember knowing that it's doctored.” 

Brain games

In the end, there's not much anyone can really do to guard against being duped by these images, says Wade. Her lab has done studies in which subjects are told that they're about to see both fake and real images. Even with the warning, people will still remember the fake photographs as real. "Warnings don't seem to have much of an effect," she says, "that's how powerful some of these fake photo manipulations can be."

Reverse image searching online can reveal fakes, but time can erase that extra context. And even with specialisation and technology, verifying an image can be nearly impossible. "Proving that something is fake is possible," says Farid, "but proving the image is authentic is virtually impossible." All experts like Farid can really say is whether or not they could find evidence of tampering.

The worry is that with images pouring in from citizen reporters from all parts of the globe, people will be confronted with more doctored images, not less. But as Farid points out, photographers have always been doctoring images in some way. They choose what to frame, what to photograph, what moment to capture and what to crop out. And some famous photographers have staged their photographs not in post-processing, but in real time. In one famous photograph from the Crimean War, bombs littered the road. But the photographer had moved them there, to make things look more dramatic. Many of Mathew Brady’s famous photographs of the American Civil War were staged, the photographer dragging bodies about to make things more gruesome. You could call these contrived, or perhaps even fake, but these images would have passed even the most rigorous of image doctoring tests.

Yet, the way we remember events has a lot to do with the photographs that go with them – from Dorothea Lange’s classic image of a mother during the Dust Bowl, to the single man standing up against tanks in Tiananmen Square. Many probably remember Romney’s Money gaff that wasn’t, or images from Hurricane Sandy that never happened, just as well as they remember real images. When asked in the future, they’ll recall those pictures, and they’ll swear they remember those things happening. "That's the most fascinating thing about memory," says Frenda, "the way that it can be so flagrantly non-factual, but we have really high confidence in the accuracy of it." And it seems there’s nothing anybody can do about it.

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