A UK Woman Has an Extra Cone Cell in Her Eyes and Can See More Colors – Futurism

In BriefMost people are trichromats, possessing three types of conecells to see color with. A woman in northern England has four typesof working cone cells, which means she has the ability to see farmore colors than most of us can.

After more than 25 years of searching, neuroscientists in the UK recently announced that theyve discovered a woman who has an extra type of cone cell the receptor cells that detect color in her eyes.

According to estimates, that means she can see an incredible 99 million more colors than the rest of us, and the scientists think shes just one of a number of people with super-vision, which they call tetrachromats, living amongst us.

Most humans are trichromats, which means we have three types of cone cells in our eyes.

Each type of cone cell is thought to be able to distinguish around 100 shades, so when you factor in all the possible combinations of these three cone cells combined, it means we can distinguish around 1 million different colors.

Most people who are color blind only have two functioning types of cone cells, which is why they can only see around 10,000 shades and almost all other mammals, including dogs and New World monkeys, are also dichromats.

But theres one doctor in northern England who has four cone cell types, taking the potential number of colors she can distinguish up to 100 million colors most of us have never even dreamed of.

Identified only as cDa29, the scientists finally found this woman two years ago, but theyve been searching for more than 25 years and think there are more tetrachromats like her out there.

So how do you get a fourth type of cone cell?

The idea of tetrachromats was firstsuggested back in 1948by Dutch scientist HL de Vries, who discovered something interesting about the eyes of color blind people.

While color blind men only possess two normal cone cells and one mutant cone thats less sensitive to either green or red light, he showed that the mothers and daughters of color blind men had one mutant cone andthree normal cones.

That meant they had four types of cone cells, even though only three were working normally something that was unheard of before then.

Despite the significance of the finding, no one paid much attention to tetrachromats until the late 80s,when John Mollon from Cambridge Universitystarted searching for womenwho might have four functioning cone cells.

Assuming that color blind men pass this fourth cone cell onto their daughters, Mollon estimated that around12 percent of the female populationshould be tetrachromats.

But all of his tests showed that these women could only perceive the same colours as the rest of us which meant only three of their cone cell types were working, so they werent true tetrachromats.

Then, in 2007, neuroscientist Gabriele Jordan from Newcastle University in the UK, who had formerly worked alongside Mollon, decided to try a slightly different test to look for this super-vision.

She took 25 women who had a fourth type of cone cell, and put them in a dark room. Looking into a light device, three colored circles of light flashed before these womens eyes.

To a trichromat, they all looked the same, but Jordan hypothesized that a true tetrachromat would be able to tell them apart thanks to the extra subtlety afforded to her by her fourth cone.

Incredibly, one of the women tested, cDa29, was able to differentiate the three different colored circles in every single test.

I was jumping up and down,Jordan told Veronique Greenwood fromDiscovermagazine.

So if so many female children of color blind men have four cones, why have we only been able to find one true tetrachromat?

For starters, the team was only looking within the UK. But the bigger issue that Jordan thinks most true tetrachromats would never need to use their fourth cone cell type, and so would never realize they had special vision.

We now know tetrachromacy exists,she told Greenwood. But we dont know what allows someone to become functionally tetrachromatic, when most four-coned women arent.

Jay Neitz, a vision researcher at the University of Washington, who wasnt involved in the study,thinks that it might take practiceand specially designed hues to truly unlock the power of tetrachromats.

Most of the things that we see as colored are manufactured by people who are trying to make colors that work for trichromats,he said.It could be that our whole world is tuned to the world of the trichromat.

In other words, the colors we use are so limited that the fourth cone cell never gets a work out.

The research on cDa29 hasnt been peer-reviewed or published as yet, and Jordan is continuing her research and search for more tetrachromats.

Theres a lot more work to be done and Jordans results need to be replicated and verified. But if we can confirm that tetrachromats really do exist, it wont just teach us about the limitations of human senses, it could help scientists develop better artificial sensing devices, and also help us figure out more about how vision works.

One thing we might never be able to understand, sadly, is exactly what the world looks like through cDa29s eyes, seeing as its our brains that truly perceive color our cone cells just receive the data to be processed.

This private perception is what everybody is curious about,Jordan toldDiscover.I would love to see that.

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A UK Woman Has an Extra Cone Cell in Her Eyes and Can See More Colors - Futurism