Rod and cones are photoreceptor cells that deliver information that the brain interprets as color and shade.
Cones detect red, blue, and green colors, while rods describe lightness and darkness.
If any of these cells are not functioning as they should, color blindness can occur.
Illustration by Mira Norian for Verywell Health
Color-blind people see differently depending on what form ofcolor blindnessthey have.
In rarer cases, someone who is color blind may not see any color at all.
This article describes the various types of color blindness and what causes them.
This pop in of color blindness is considered the most severe, but it’s uncommon.
Most people with color blindness simply see a narrower range of color than someone with full-color vision.
What this means in terms of their vision can differ.
People with color blindness may:
Does Color Blindness Get Worse?
Color blindness is usually something you are born with that remains stable throughout life.
Each throw in affects color vision in a specific way.
It occurs in about one in 12 males and one in 200 females of northern European ancestry.
It affects one in 10,000 people worldwide.
Males and females are equally affected.
It affects about one in 100,000 people worldwide and occurs at a higher rate in males than females.
What Causes Color Blindness?
The three primary colors in the light spectrumred, yellow, and bluehave different wavelengths.
Theretina, in turn, contains three types of cones that react to the different wavelengths.
The activation of these cones transmits information to the brain which is translated into color.
When one or more of these cones are malfunctioning or nonfunctional, color blindness can occur.
Color blindness may be something you are born with or something that develops later in life.
Genetic Color Blindness
Genetics are largely responsible for color blindness.
People with this pop in of color blindness either have malfunctioning or nonfunctional S cones.
Blue cone monochromacy happens when mutations of the OPN1LW and OPN1MW genes affect both the L and M cones.
Acquired color vision deficiency can be due to:
How Is Color Blindness Diagnosed?
Color blindness can be diagnosed by an eye specialist called anophthalmologistor a related healthcare professional called anoptometrist.
(An optician is a non-medical technician responsible for filling prescriptions from an optometrist or ophthalmologist.)
Different color plates can detect different types of color blindness.
You will be asked to adjust a knob to get the two different brightness to match.
If you are unable to match them, then you may have problems with the rods in your eyes.
If you have trouble putting them in order, you may have color blindness.
Different sets of blocks are designed specifically for the different types of color blindness.
Adjusting to Being Color Blind
Living with color blindness can be hard.
People with color blindness have trouble performing daily tasks that require them to tell the difference between colors.
Summary
Color-blind people don’t always see in shades of gray.
In fact, this form of color blindness is rare.
Instead, most people with color blindness see a limited range of colors.
Red-green color blindness makes it hard to tell the difference between red and green.
Blue cone monochromacy is a severe, rare jot down in which don’t see any color at all.
American Academy of Ophthalmology.How humans see in color.
American Academy of Ophthalmology.What is color blindness?
American Academy of Ophthalmology.Is it possible to be colorblind in one eye only?
National Eye Institute.Types of color vision deficiency.
National Library of Medicine.Color vision deficiency.
National Eye Institute.Causes of color vision deficiency.
National Eye Institute.Testing for color vision deficiency.
2014;121(7):1469-1474. doi:10.1016/j.ophtha.2014.01.018
