#TheDress Revisited: A Neuroscientist Studies the Viral Color Perception Debate

More than two years later, a study looks closely at the differences in color perception that fueled widespread debate over "The Dress."

Back in February 2015, an odd question seized widespread attention and immediately went viral online: What colors are this dress?

Some believed that a dress worn by a mother of the bride at a wedding in Scotland and shown in a much-discussed photo was blue and black. Others saw it as being white and gold. Vigorous debate between the two camps fueled interest in the question, which spurred a wider consideration of how humans perceive color in the world — and if, in fact, we’re all seeing the same colors.

Surely, the dress and the unexpected vigor of the debate over its coloring left a big impression. More than two years later, a new study conducted by New York University looks closely at why people viewed the colors differently.

According to Pascal Wallisch, who teaches psychology and neuroscience at NYU, the answer lies in the shadows.

“It comes down to how we perceive how the dress was illuminated,” Wallisch explained.

Among the people who thought the dress was in a shadow, 80 percent saw the colors white and gold. Those who believed the dress was illuminated by artificial light were more likely to see it as black and blue.

In Wallisch’s study, which was published in the Journal of Vision, 13,000 participants were asked 21 questions, including their age, gender, if they are a night owl, whether they believed the garment was in a shadow, whether they believed it was illuminated by artificial or natural light, and, of course, what colors they saw in the dress.

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Wallisch hypothesized that the different perceptions of colors might be influenced by self-identified circadian types, or whether someone is an early riser or a night owl. People who get up early in the morning and go to sleep by sunset — who spend more time in natural light, which is blue — are more likely to see the dress image as white and gold. The neuroscientist explained that if you subtract the color blue (the color of natural daylight) from gray, you’ll get yellow — which could explain the greater likelihood of that color among early risers.

In contrast, people who stay up late and see more artificial light than natural light are more likely to see the colors blue and black. If you subtract yellow (the color of artificial light) from gray, you’ll get blue.

“Whatever kind of light one is typically exposed to influences how one perceives color,” he explained.

While age or gender didn’t seem to have much of an impact on perceived color, personality could be an area that researchers might want to further explore. Different personality types could coincide with the idea of adopting early or late bedtimes, Wallisch noted.

Another interesting finding: the vast majority of participants over the age of 65 saw the dress as blue and black. Wallisch said he isn’t sure whether this has something to do with the evolution of vision over the years or whether retirees just aren’t spending as much time outside and are limiting their exposure to natural daylight.

In any event, his study opens a window to the idea that our perceptions might differ more than we think.

“People see the world differently,” Wallisch remarked. “We need to start respecting that other people might see the world differently based on who they are.”

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