I don’t write about colorblindness in children much, largely because it is not something that can be corrected with glasses or contacts or patches.  But it is certainly a component of vision, and a very important one for children (and adults).

Recently, a friend contacted me because his son was recently diagnosed as having moderate-to-severe colorblindness with greens.  As he said “he literally couldn’t see the numbers hidden in the Ishahara plates, for many of them. It was both scary and eerily fascinating.”  While I don’t have any first-hand experience with color blindness, I certainly can relate to how hard it is to watch your child struggle to see something in a vision test.

Child taking a color vision test.  Image credit: National Eye Institute, National Institutes of Health Ref#: EE56

What is color blindness or color vision deficiency?

“Color blindness” is actually a misleading term, the more accurate term is “color vision deficiency.”  Nearly everyone can distinguish some colors, but people with color vision deficiency have trouble seeing differences between certain shades of colors.  The most common types of color vision deficiencies are with shades of reds and greens.  People with normal color vision can distinguish more than 100 different colors.  Those with strong color vision deficiencies may only be able to distinguish 20 colors. 

Color vision deficiency is usually hereditary, though it is sometimes caused by injury.  Color vision is encoded on the X chromosome, which means that men are far more likely to have color vision deficiencies than women.  About 8% of men and about 0.5% of women have a color vision deficiency.  Some people truly are “color blind” in that they cannot see any colors at all.  This is called “achromotopsia” and is very rare: it affects around 1 in 30,000 people.  Achromotopsia is also associated with poor visual acuity and nystagmus.

What is it like to have color vision deficiency?

This is a short documentary that was put together to explain color vision deficiency to children.  It is based on the longer documentary, “No such thing as color.”

What does it mean for my child to have color vision deficiency?

Colblindor has a pretty sweet interview with two boys with color vision deficiency asking about what they see in terms of color.  One question was whether they see rainbows, both boys answered yes.  As the author states,

even if they really have some problems with colors their life is still very colorful.

Unfortunately, children with color vision deficiencies will often have trouble at school.  Many worksheets and exercises are color coded (“color the circle red” or “how many green dots are there?”), and later, charts and graphs used in assignments often have a color component.  These can be very difficult and frustrating for children with color vision deficiency.  That’s why, if you know that your child has color vision deficiency, it is important that you talk with his or her teachers so they all know about it and can adjust those accordingly.  Color deficiency is common enough that statistically, there will be one student with color vision deficiency in each classroom.  However, you may still need to advocate for your child and make sure he or she receives the adaptations they need in school.  There’s a nice post at ColorVisionTesting that talks about ways teachers can help their students with color vision deficiency.

Should I test my child’s color vision?

Children normally develop full color vision by 6 months, but as most parents will tell you, they won’t know their colors by name until well past that age.  At age 2, they should be starting to match colors, around age 3 beginning to name colors, and between 4 and 6, have good color naming skills.  Parents of children with strong color vision deficiency often start to notice problems between the ages of 3 and 10.  If you’re noticing that your child is consistently confusing colors or naming colors incorrectly, they should be tested before starting Kindergarten.

There are online color vision tests, but you will need to see an eye doctor to diagnose color vision deficiencies accurately.

More Reading

I relied very heavily on the excellent Colblindor website for this post.  Some good articles to start with:

• Colorblindness is a part of a web exhibit on color.  It has a really good overview of the types of colorblindness, causes, and tests.  There’s also a very nice vision simulator that lets you choose different pictures and different types of color blindness.
• Is my son colorblind? (this is also applicable to daughters, just boys are much more likely to have color vision deficiencies).
• How to explain color blindness to your little boy
• How to help your color blind kid
• 50 facts about color blindness
• 5 online color blindness tests links and explanations of some of the different types of tests.  Note: make an appointment with an eye doctor if you suspect your child has a color vision deficiency.
• Color Blind Home Page is a site written by publishers of a color vision test.  The site has a lot of good information about color vision deficiency.  This site offers a free online test for color vision deficiency, but make sure you see an eye doctor for a final diagnosis.

Books!!

There are a few books that I found for kids about color vision deficiency.  I have not read these books, I welcome any reviews or other recommendations:

• Seeing Color: It’s my rainbow, too – written by Arlene Evans, a school nurse who worked with many kids with  color vision deficiency.  For ages 9-12 (though one review I read said it would be appropriate for kids as young as 5 or 6).  Includes a glossary of key terms.
• All about color blindness: A guide to color vision deficiency for kids – written by Karen Rae Levine, the mother of a boy with color vision deficiency.  The book follows the story of Cory, a 4th grader who learns he has color vision deficiency and learns to deal with situations that come about because of it.  This one has been awarded the Mom’s Choice Award, Next Generation Indie Book Award, and National Indie Excellence Book Award.
• Erik the Red sees green: A story about color blindness – by Julie Anderson. Erik has troubles in school and at soccer until he discovers that he has color vision deficiency.  He and his friends and teachers figure out ways for him to overcome the difficulties.  For ages 4-7.
• Just like Grandpa: A story about color vision deficiency – by Elizabeth Murphy-Melas.  Ben learns that he has color vision deficiency, just like his grandpa.  His grandpa shares guidance and support and ways to adapt.