Out of Sight, Top of Mind

The murky territory of memory isn’t as ambiguous as you may think. Research led by MIT’s Aude Oliva shows that how memorable a photo is can be quantified and even predicted. (Dillon Lee/Exploratorium)

Think about the last time you flipped through a magazine, or scrolled through Facebook. Can you remember the photos you saw? If you saw the images again, would you know it? Chances are, some of the photos stuck more than others — but probably not the ones you’d expect.

“When it comes to memory, we found that there is this dissociation between what we find beautiful and interesting and what we will actually, truly remember,” said Aude Oliva, a cognitive scientist at MIT and an Exploratorium Osher Fellow. Oliva, who is also the scientist behind this optical illusion, visited the Exploratorium in May and gave a talk during an evening program focused on photography.

Oliva’s research team is working to understand and unlock how memory works. By putting thousands of people to the test, or rather, the Visual Memory Game, Oliva’s team has been able to study what kinds of images we’re likely to remember and what kinds we’re all but certain to forget.

The Visual Memory Game worked by giving participants “a sequence of images, each of which was displayed for 1 second, with a 1.4 second gap in between image presentations,” according to the team’s report. “Their task was to press the space bar whenever they saw an identical repeat of an image at any time during the sequence.”

The results were consistent: participants across the board remembered some photos, and forgot others. That consistency led to the creation of a predictive algorithm and interactive website: in goes the image, out comes the memorability score.   

Speaking to a crowd of more than 150 in the Exploratorium’s Kanbar Forum, Oliva conducted an augmented version of the Visual Memory Game by asking the audience to clap every time they saw a photo repeat in a long string of images.

In the beginning, it was easy: the claps came fairly consistently and the audience was largely in sync. But everything changed when Oliva began flipping through the no man’s land of patterns and textures.

The audience (this writer included) started to lose it. The unison clapping of the auditorium began sounding like popcorn. 

The reason, Oliva said, is because the photos were literally meaningless: blurs of blues and greens followed by more blurs of blues and greens that had no semantic meaning, nothing for the audience to grasp onto. And the brain can’t remember “nothing”; memory needs meaning.

“We did not evolve as a species to look at photos,” Oliva said. “We evolved as a species to go through the world.”

That means the brain is wired to remember things that are important, novel, or even dangerous. While there isn’t a formula for taking the perfectly memorable photo, there are several factors that help, such as having one point of focus or some sort of movement.

The memorability of the photo increases when it shows movement that is about to happen rather than a completed movement. Imagine a photo of a runner handing off a baton, and another photo of a runner holding one: it’s the hand-off that’s more memorable than the hold.

“We think in 3D and we think in time. We imagine the motion,” Oliva said. “If we are given half of the motion, we finish it up.”

While Oliva’s studies on memorability are a marketing director’s dream (who doesn’t want to have the most memorable ad campaign in town?), they also lend themselves to creating better mnemonic devices for learning and treatments for diseases that affect the brain. The latter is what motivates Oliva, whose grandmother died of Alzheimer’s disease.  

So far, modern medicine can’t catch Alzheimer’s early enough to stop it; by the time the diagnosis comes, the disease has taken root. That’s where Oliva said her research may be able to help: If a person can’t remember photos that are consistently memorable to a wide range of other people, that can be an early indicator something might be wrong with that person’s memory. And an early indicator could mean the difference between losing your memory and keeping it.

“How can you stop Alzheimer’s?” she said. “By stopping it early.”