In some ways, vision is predictable. Humans rely on good eyesight to perform complex tasks like making breakfast, driving to work and scanning a document for important phrases. When everything goes right, you hardly notice that your eyes are working overtime to keep you going.
However, there are quirks to your vision that you might not even know about. While the ability to discern colour definitely impacts your skill in determining objects in your field of vision, how your brain processes hues and tones may not be the same as others’. What if your green wasn’t the same as your neighbor’s? What if when you picked up a red crayon, someone else sees you draw purple?
If this sounds farfetched, read on about how people process colour differently to learn what role language and the brain have in your eyesight.
A difference of opinion
Jay Neitz, Ph.D., is a professor of neurology whose research focuses on the way humans perceive colours, and he told Live Science that while the human eye is structurally similar in the vast majority of people, the colours they see are not.
“I would say recent experiments lead us down a road to the idea that we don’t all see the same colors,” Neitz told the source.
The eye uses microscopic cells calls rods and cones to gather visual information on physical scenes. Rods collect wavelengths of monochromatic light, while cones are responsible for capturing and transmitting colour. However, Neitz explained that it isn’t until those signals reach the brain that visual-processing areas give rise to what you perceive of as the visual world.
In fact, it’s this disconnect that gives rise to the potentially troubling issue of differences in colour perception. After all, science publisher Sinauer Associates explained that colour isn’t an inherent property of objects you look at, but rather a perception of them due to light reflecting off external surfaces. It’s only after those rays of light enter your eye and are processed by your brain that you see hues and pigments.
Colour me surprised
If you’re still a bit skeptical about the fluid nature of colour perception, it might help to think of how children around the world grow up learning about how they see the world. While you might think that it’s more or less the same wherever you go, the American Psychological Association explained that different languages actually have tremendous impacts on how speakers process visual colour information.
The APA outlined a study that followed groups of children in southern England and northern Namibia, a country on Africa’s southwestern coast. Both groups grew in wildly different cultural and linguistic surroundings, and the researchers identified 91 children whom they would follow for a longitudinal sample.
The researchers were interested in exploring the effect that linguistic restrictions have on colour perception. For example, English has words for basic colours like black, white and blue, but more specific hues require created or niche titles. The researchers provided the children in the study with 22 coloured squares to represent basic colour concepts in English, as well as 11 coloured squares to demonstrate in-between pigments.
When the researchers tested the Namibian children using English colour concepts, the participants had difficulty grouping blocks in the right context. Moreover, many tried to argue in favor of their choices, which the researchers explained as inherent logical colour systems rather than blind shots in the dark.
Protect your colour
Differences in colour perception don’t usually mean anything for your overall vision health, but there are some instances where damage to the cone cells in your eyes can result in problems that lead to poor eyesight.
Retinitis pigmentosa is a progressive vision loss condition that robs people of their abilities to see in the dark and at the periphery of their field of vision. While there are multiple causes for RP, cone cell damage is a leading one. Congenital factors can lead to cell death after a certain period of time, and though there is generally little light at night, cone cells still allow you to discern contrast in low-light situations.
While most people never have to worry about RP, gene therapy can predict whether you may develop the condition. Regular eye exams also help detect the condition in its earliest stages so treatment can begin as soon as possible.
As scientists continue to explore how the human eye and brain combine to process the physical world, there might come a day when you’re able to see colours you’ve never experienced before. If this sounds like science fiction to you, remember that high-tech procedures like LASIK were once considered impossible, too.
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