What is colour blindness in children?

You have probably already heard of colour blindness, this hereditary disease that alters colour vision. But do you really know how this vision disorder develops and what it entails in the child’s life?

François-Xavier Borruat, a full professor and head of the neuro-ophthalmology unit, explains everything you need to know about this ocular pathology.

How does vision work?

Before we start talking about colour blindness, it’s important to understand how our eyes work.We have the ability to see thanks to the retina, because it contains receptors called rods and cones. 

The rods come into play when the light is dim, for example during the night. 

As for cones, they are useful for daytime vision. They allow very precise central vision, when reading and for colour vision.

How do we perceive colours? 

We identify colours correctly using the three families of cones that work together to provide a normal perception of colours. Colour blindness is a congenital, non-evolving genetic condition in which a family of cones is missing. A colour-blind person is therefore a person who distinguishes colours with different intensities. 

How will the vision of the colour-blind child change?

This visual impairment does not evolve and is not associated with vision loss. The only problem concerns colour vision, which is not normal. 

This is a very common pathology, since 7% to 8% of men in Northern Europe or North America have some form of colour blindness. It is a generally hereditary disease that is transmitted by chromosomes. 

Colour-blind children live very well with this genetic disease, they simply see things differently and grow up with their own vision of colours. 

How can you tell if your child is colour-blind?

It is difficult for a colour-blind child to become aware of this anomaly on their own, because they have no symptoms and live their life like everyone else. This difference is most often detected by the family or teachers.

Colour blindness is detected with very simple tests that make it possible to evaluate the perception of colours. If in doubt, please contact an ophthalmologist for a diagnosis. However, do not worry, the visual prognosis is not bad. People with colour blindness remain colour-blind for the rest of their lives, but their visual function remains normal. 

Do people with colour blindness perceive red and green?

There is a myth about colour blindness. The myth is that a child diagnosed with colour blindness does not see the colour green or red. This statement is actually wrong. 

Colour blindness confuses pairs of colours: a colour and another very precise colour will be confused. But if one of the colours is a little different, a little more red or a little more green, in slightly different shades, the colour-blind person will not confuse the colours.

Find out more about this colour perception disorder

Do you want to learn more about colour blindness? Check out our page on this pathology.

And if you are looking for information on other visual disorders, go to our eye diseases pages. We detail pathologies such as amblyopia, strabismus, myopia, astigmatism or hyperopia.