Scientists Say Olo is A New Color that Only Five People Have Seen

While following their curiosity, researchers developed new technology which they used on themselves and discovered new things about our color perception

Hiya!

I remember walking in a park as a kid with my dad and asking him if he saw the same shade of green grass as I did. He told me he didn’t know, that no one could ever know because we can’t experience how other people perceive the world. The concept shocked my young mind, and the conversation has stuck with me ever since.

I’ve shared that memory before, so I apologize if you’ve heard it. I’m sharing it again because while scientists understand a lot about the mechanics of our vision and have ample knowledge about its mechanics, precisely how our minds construct the images and colors that our eyes perceive remains a mystery. However, some curious researchers may have brought us one step closer to an answer — and introduced us to a new color in the process.

Color Perception

Unbeknownst to me at the time, my childhood curiosity about the subjectivity of color touched on a conundrum philosophers have fretted over since the late 18th century.

Zed Adams, a philosophy professor at the New School for Social Research who specializes in the experience of color, told Ross Andersen of The Atlantic that many philosophers were "haunted” by the possibility that we’re each trapped in our own perceptual reality, and how,

“Everyone wants to believe that they see the true rainbow, but no one can be sure that they do.”

Then, in 1794, chemist John Dalton discovered red-green color blindness by studying his own vision and learning that he confused red with green and pink with blue. Since then, scientists have learned an impressive amount about our visual perception.

However, our retinas, which are light-sensitive tissues that line the back of the eye, are most involved in color perception and our ability to see details.

Retinas are made up of approximately 120 million rods and 6 million cones. Rods are sensitive to light levels and tell us how dim or bright they are, but cones provide us with color vision.

Most people have three types of cones — S, M, and L — that detect light wavelengths. It’s estimated that about 10 percent of our cone cells are S cones, which respond to shorter wavelengths of light that we perceive as blue. Meanwhile, around 30 percent are M cones, which are triggered by medium light waves that we see as green. However, at 60 percent, L cones make up the majority and react to long wavelengths that we interpret as red.

These blue, green, and red signals from our cones are sent to our brain, where they’re added into the full-color vision we experience. With just these three types of cone cells, scientists estimate we can see and differentiate between about 10 million color hues.

As an aside, there’s also a rare and mysterious condition called tetrachromacy, which exclusively affects females. It’s thought that about 12 percent of females have a fourth cone type that is more sensitive to lightwaves in the orange spectrum. This enables them to see hundreds of times more color hues than the average person. The condition is poorly understood, though research indicates females’ bonus X chromosome may have something to do with it.

Anyway, tetrachromacy or not, part of why we can see so many hues is that the various cone types process overlapping ranges of lightwaves. For instance, lightwaves that trigger M cones will also stimulate either S or L cones.

Interestingly, while the S and L cones can activate independently and in isolation with light wavelengths at the far ends of the spectrum, the same is not true for M cones.

Ren Ng, a professor of electrical engineering and computer science at the University of California, Berkeley, explained to Jacek Krywko of Scientific American,

“There’s no light in the world that can activate only the M cone cells because, if they are being activated, for sure one or both other types get activated as well.”

Considering this, Ng and his colleagues became curious about what would happen if the M cone, and only the M cone, were stimulated.

The Study