Why You Might Be a Tetrachromat with Super Human Vision
After decades of searching, scientists have discovered one woman who can see spectrums of colours that we can only imagine. Surprisingly, this super human vision may be how 12% of the female population is viewing the world right now. Work is currently underway developing tests to confirm this.
This super vision, known as tetrachromacy, is when a person has the ability to see 99 million more colours than the average eye. Most of us are categorized as trichromats, which means we have three types of cone cells collecting data and sending signals to our brains to perceive colour. Colour blind individuals only have two cones functioning, along with one mutant non-functioning cone. Tetrachromats, although they don’t realize it, have four functioning types of cones cells in their eyes. Since each cone allows us to distinguish approximately 100 shades of colour, the average person can interpret about a million tones. With four cones accessible, tetrachromats can view an estimated 100 million colour combinations. Scientists have been studying this abnormality since the 1980s, but only recently has one researcher figured out how to confirm it.
Investigations have narrowed it down that this additional tetrachromat cell, identified as cDa29, is found in 12% of women. Since mothers and daughters of colour blind men have one mutant cone and three normal cones, the assumption is that colour blind men can pass down this fourth cone cell to their daughters. This mutant cone is less sensitive to either green or red light. When this additional cone is added to an average trichomat’s visual cell structure, tetrachromacy is possible.
Once women with the fourth type of cone cell were targeted as possible candidates, researchers devised a test to attempt confirmation. Using a light device, three coloured beams of light were flashed in front of test subjects. If the test subject retained the fourth functioning cone, they were able to tell the subtle differences between the colours of flashing light.
So far, Only one true tetrachromat woman has been discovered. Work will continue to refine the experiments and search for more tetrachromats within the assumed 12% female population. This has proven a challenge thus far, since scientists are trichromats and are developing the tests for a sight range they cannot perceive. Eventually the goal is to confirm that tetrachromats exist, teach us about the limitations of human senses, develop better artificial sensing devices, and learn more about how vision and our brains work.
If you’re interested in learning more about the theories behind eye colour, read our blog on the fascinating variations found in human eyes.