What is the “lighter shade of pale”? How many shades have gray? Do we all see the sky as blue and roses red, white, yellow, or pink?
Cone cells in the retina of the eye detect colors. People react to colors depending on the number of cone cells, and women are said to have up to four of such cells so they can see a broader spectrum of colors than men. This is one of the salient highlights in the report “Why We Don’t See the Same Colors” by Prof. Berit Brogaard, published in the magazine Psychology Today in June 2020. She explained that people see colors differently based on their gender, national origin, ethnicity, geography, and language.
Professor Brogaard is the director of the Brogaard Lab for Multisensory Research at the University of Miami.
Nothing is objective about colors, she summarized.
Brogaard’s article cited recent studies suggesting that people have a varying perception of colors based on how a gene in the “X chromosome” reacts. “X chromosome” codes the protein that detects light in the red-orange wavelength regions of the color spectrum.
Thus, people distinguish colors depending on the number of cones, called photoreceptors, in the retina. Cones, or cone cells, respond in varied manners to the light of different wavelengths. It is the part of the eye that is responsible for color vision. Cones vary in numbers.
Sometimes, cones are not present – the condition generally referred to as color blindness. “The difference in one or more cones can make a person color blind,” explains another article published by a United States-based health magazine Bausch+Lomb.
Colorblind persons have only two cone types, the report said.
Color blindness results when one or more of the cone cells are absent or not working. So, the brain detects different colors.
A person is color blind when he or she experiences difficulty distinguishing colors or having a hard time seeing shades or tones of the same color.
Medication cannot cure color blindness. However, there are available contact lenses with filters to help color blind people correct the deficiency.
Many eye health care outfits offer different contact lenses to help ease the difficulty in sensing colors. One is Sears Optical, a Sears chain of department stores in the United States and an Italy-based eyewear company, Luxottica division. Sears Optical has a wide collection of quality eyeglasses, contact lenses. Their well-trained optometrists give professional services.
Also, some LensCrafters prescribe corrective eye wears. Considered as the largest optical retailer in America (it has 90 stores in California alone), LensCrafters has outlets in many countries worldwide. LensCrafters believes that “vision care is a lot more than a prescription or a pair of eyewear.”
When one or more cone cells are absent, not functioning, or detect different color than what has generally perceived it is, it is color blindness. When all the three-cone cells are not there, then it is severe color blindness. Mild color blindness is when one of the cone cells present does not function.
Those with mild color deficiencies can see colors normally in good light but find it difficult to determine colors in dim light. Others cannot distinguish certain colors in any light. The severest form of color blindness is when everything is in shades of gray. It is important to understand that color blindness usually affects both eyes equally and remains that way for life.
Sometimes, color blindness is congenital and can only be detected later.
Aside from the color blindness issue, there is more about how people react to or distinguish colors differently.
Brogaard adds that since the number of cones, or photoreceptors, in the retina is not constant, this is one factor considered how people with a different number of cones measure the input from the retina in varying manners. There is a test on how color vision varies. Some people believe that their best example of red “is what others pick as their best example of orange.”
There is more about how people see colors differently. Ophthalmologists explain that the cones in human eyes vary, suggesting that the brain can readily adjust the input from the retina. Therefore, that variation in color perception does not solely depend on the number of cones or photoreceptors but also how people fine-tune the retina’s input based on the number of cones.
Cone cells, which are concentrated near the center of our vision, distinguish colors. Thus, to determine color perception, the brain uses the cones’ inputs that see the colors red, green, and blue.
Aside from cones, there is another cell that detects light in the retina – the rods. Rods read-only light and dark and are too much sensitive to low light levels.
The Monkees, an American counterpart of The Beatles, sang in the 1960s: “But today there is no day or night/ Today there is no dark or light/Today there is no black or white/Only shades of gray. Perhaps the group referred to the most severe form of color blindness when they recorded “Shades of Gray.”