Color Blindness: How it Works (or Doesn’t)

Do people see true colors? Turns out, the true color of a tennis ball went pro, garnering international attention. The debate: Is a tennis ball yellow or green? It all started with a Twitter poll and Time magazine wrote an article about it in March 2018. Roger Federer, winner of 20 Grand Slam tournaments and labeled by many as the GOAT (Greatest of all Time), weighed in on a video that has gone viral. “They’re yellow,” according to Fed, whose decisive response only created further fussing among Twitter responders. Color perception—the way we perceive light—is blamed for the strong differences of opinion.

Color Blindness Statistics and Facts

Are we to believe the GOAT? Both men and women can suffer from color blindness, however the color vision deficiency (CVD) affects far more men. Color blindness affects approximately one out of every 12 men (8%) and one in 200 women (.5%) in the world. So…

Most of us share a common color sensory experience, however some people (more men) have CVD which means their perception of color is different from what most people see. As the deficiency develops, it becomes the condition color blindness. People with may not even be aware of their condition unless they receive testing in a doctor’s office or a laboratory. Inherited or genetic color blindness results from abnormal photopigments. Other causes: Trauma, physical or chemical damage to the eye, the optic nerve or part of the brain that process color information; the result of diseases such as diabetes or multiple sclerosis; toxic effects of some drugs; the aging process, most often because of a cataract which is a clouding of the eye’s lens.

Symptoms of color blindness include difficulty seeing colors and their brightness and inability to distinguish between shades of the same or similar colors. This occurs most with red and green, or blue and yellow, according to the American Academy of Ophthalmology. The inability to see any color at all and to see things only in shades of grey is called achromatopsia. Those with this disorder commonly experience amblyopia, nystagmus, light sensitivity and overall poor vision.

More Interesting Facts

  • Color vision tests are important for some jobs including police officers, firefighters, airplane pilots, railroad workers and people serving in the military.
  • Color blindness can affect culinary capabilities and clothing choices. People who are red-green colorblind may not be able to tell if their meat is thoroughly cooked because they cannot determine various shades of red. Also, many color blind people have problems buying ripe produce, like bananas, and matching their clothes.
  • Ninety-nine percent (99%) of all color blind people suffer from red-green color blindness, including Mark Zuckerberg, Facebook founder with the iconic blue logo.
  • Color blind people may feel at a disadvantage in everyday life, but almost no one recognizes this. And many people learn to adapt. A Colblindor is a person who has learned to enjoy life color blind.
  • Contrary to popular belief, dogs are not completely color blind. Our four-legged friends actually do see color, but many fewer colors than humans do.

Types of Color Blindness… and Treatment

There are three main types of color blindness, based on photopigment defects in the three different kinds of cones (in the eyes) that respond to, or perceive light. Red-green color blindness is due to the loss or limited function of the red cone (protan) or green cone (deutan) photopigments. Blue-yellow color blindness is much rarer. Blue-cone (tritan) photopigments are either missing or have limited function. Total color blindness, or monochromacy, is a very rare condition where there is a complete absence of color, and visual acuity may also be affected.

Eye care professionals use a variety of tests to diagnose color blindness based on type and severity. Ishihara plates are the best known color blindness tests, but may not be the most accurate ones in use today. Instead most doctors today use an anomaloscope, the most accurate color blindness test today.

Currently, color blindness has no cure. However, people with the most common red-green color blindness can use a special set of colored lenses or glasses to help them perceive colors more accurately.

If you have any concerns about general eye care, color blindness or cataracts, consult with our specialists at Mann Eye Institute.