Why did we see 'the dress' differently? The answer lies in the shadows, new research finds

Works for me. I'm a night owl, and do see the dress as blue and black/gray.

https://www.eurekalert.org/pub_releases/2017-04/nyu-wdw040317.php

Public Release: 7-Apr-2017
Why did we see 'the dress' differently? The answer lies in the shadows, new research finds
New York University

When "the dress" went viral in 2015, millions were divided on its true colors: gold and white or black and blue? In a new study, New York University neuroscientist Pascal Wallisch concludes that these differences in perception are due to our assumptions about how the dress was illuminated.

Those who thought that the dress, worn by the mother of a bride at a wedding in Scotland, was photographed in a shadow likely saw the garment as gold and white; by contrast, those who thought it was illuminated by artificial light were more likely to see it as black and blue.

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"Shadows are blue, so we mentally subtract the blue light in order to view the image, which then appears in bright colors--gold and white," Wallisch continues. "However, artificial light tends to be yellowish, so if we see it brightened in this fashion, we factor out this color, leaving us with a dress that we see as black and blue.

"This is a basic cognitive function: to appreciate the color on an object, the illumination source has to be taken into account, which the brain does continuously."

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He hypothesized that differing perceptions could be linked to one's exposure to daylight--quite simply, people who rise and go to bed early, and spend many of their waking hours in sunlight (i.e., under a blue sky), are more likely to see the dress as white and gold than are night owls, whose world is illuminated not by the sun, but, rather, by long-wavelength artificial light.

To test this, he asked participants if they go to bed early and feel best in the morning (i.e., "larks") or if they like to sleep in and feel best at night ("owls"), then matched this self-identified circadian type with how they saw the dress. Consistent with the hypothesis, larks were significantly more likely to see the dress as white and gold--relative to owls--underscoring the relative effects of exposure to daylight.

"This suggests that whatever kind of light one is typically exposed to influences how one perceives color," Wallisch says.

Conversely, demographic factors such as gender and age had comparatively small effects on the perception of the dress image.

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