New research has led scientists to believe that people may not see all the same colors when they look at the same things. It comes down to color perception. Although most of us would agree that red is the color of tomatoes, strawberries and stop signs, scientists now think that one person's red could be another person's blue. Research has led scientists to believe that new techniques might one day allow color-blind people to see colors again and blind people to see once again, too! Find out more about color perception today and what colors you see!
Did you know that your brain is actually the organ that “sees” instead of the eyes? The tissues that work together in the eye send signals to your brain that tell you what you are actually seeing. The eye is extraordinary and complex. Light rays reflect off what you are looking at and enter the eyes through your cornea. Your cornea reacts to that light by bending (also called “refracting”) the light rays that pass through your pupil (the black center of your eye). The colored part of your eye—the iris—constricts and opens depending on the amount of light that is hitting your eye. These movements of your iris affect the size of your pupil, making it smaller or bigger.
This allows light to pass through the lens of your eye, hitting other tissues. The lens of your eye (behind the black center of your eye) is a tissue that bends light rays and focuses it on your retina. This is a light-sensitive tissue in the back of your eye that changes the light that hits it into electrical impulses. These impulses are sent to the brain via the optic nerve (or main nerve in the eye). The brain then tells you what you are seeing. That is how your vision works. Many tissues have to interact with the light that you see to create an image for your brain to interpret.
The vision process is the same for every person. However, color perception is different in some people. Color perception (or the colors you see) depends on if parts of your eyes are working correctly. We mentioned the retina of the eye and how it is a light-sensitive tissue that communicates with the brain. This thin layer of tissue houses millions of microscopic light-sensing nerve cells that we call rods and cones. These are the cells that send impulses to your brain, interpreting colors from lightwaves.
The cones reside in the center of your retina. When they are exposed to bright light rays, they deliver sharp, clear vision with all the colors of the rainbow. They also help you to see objects in fine detail. Cones lie right in the middle of the retina tissue in a part we call the “macula”. The rods are another type of cell that lies just outside this center macula part of the retina. Rods reach the outer edge of your retina, basically meaning that the retina has two different types of cells that help you in color perception. Rods provide peripheral vision and act as motion sensors. These cells are also charged with helping you see at night or in dimly-lit locations.
Rods and cones don’t work the same in every person. They may malfunction slightly, meaning your color perception is only a little off. However, severe forms of abnormal color perception are referred to as “color blindness”. This means that people with color blindness aren’t aware of specific color differences like the rest of the population is. You may see a stop sign as being bright red, while someone with red-green color blindness sees that stop sign as a hue of green. 8% of men and 0.5% of women have color blindness. In many cases, this trait is inherited by males from a mother who had genes for abnormal photopigments. This will make the cone cells work differently in the eye than they should.
There are three different types of color blindness:
Red-green - This happens when your red cone is abnormal, meaning you either don’t have the red and green photopigments, or they have limited functions. Things that should look red, appear gray or green and things that should appear green look brownish-yellow. Most patients either have one cone missing or have limited function in one of their color perception cones.
Blue-yellow - Your blue cone photopigments are either missing or only slightly work. Blue will appear greener than it is and yellow will look violet or gray.
Total - This is total color-blindness, meaning you don’t see color at all. This color perception—or lack of it—is extremely rare.
If you have color blindness, you may or may not realize that your color perception is different than others. The colors you see are natural to you until you get your eyes tested and find out that your color perception is off. We have tests to see what color perception you have. Once we test you, we can help you know how to improve your vision and your color perception. Patients with color blindness can receive special glasses through our office that help them to see colors correctly. Many people don’t know they have color blindness unless their eyes are tested by a professional eye doctor. To have your vision test today, schedule a consultation with Optical Masters by calling (720) 780-8881!