Vancouver Optometrists & Eye Doctors

4466 West 10th Avenue
Call: 604-224-3937

What Is and What Causes Colour Blindness?

Monday, May 25, 2015 @ 04:05 PM
Author: Amit Mathur

image00

You know how when you are walking outside and you see a beautiful red rose in a garden or on a sunny day, the grass seems greener then normal? Well, not everyone can see those bright and vivid colours the same way. Some people are colour blind.

What Is Colour Blindness?

In a nutshell, colour blindness is when someone is unable to see colours properly under normal conditions and it affects as little as 8% of men and 0.5% of women.

Being colour blind doesn’t necessarily mean you cannot see anything. What it means is that you have are unable to see colours fully the same way as others. There are different types of colour blindness.

What Causes Colour Blindness?

There are different causes, but for the most part colour blindness is caused by genetics which are passed down by your parents.

Research has shown the reason men are more likely to be colour blind then women is because it is a sex-linked trait meaning it is carried on the X chromosome. This explains why colour blindness is more common in men, because they only have one X chromosome, and if that chromosome does not have the proper code they will be colour blind. Whereas a female receives two X chromosomes, so even if one of them is deficient, as long as the other one has the proper coding, the female will be able to see colours without problem.

Colour blindness can also be caused by physical or chemical damage to the eyes, the optic nerves or part of the brain. Other diseases such as diabetes and multiple sclerosis can also cause colour blindness.

Types of Colour Blindness

  1. Total colour blindness is very rare, but can occur in some patients. This results in someone not being able to see any colour at all. It’s like living in a black and white movie; you can see different shades of black, white and grey, but no colour.
  1. Red/Green colour blindness is by far the most common and affects the way they see colours that contain red and green components. For example, some who is red/green colour blind will mix up a blue and a purple colour because they cannot differentiate the red element of the purple. So in a box of 24 colouring pencils, someone with red/green colour blindness can only identify five of the 24 colours.
  1. Blue/Yellow colour blindness means the person has a reduced sensitivity to blue light and therefore blue-yellow colours, and is rather rare. This means the person has trouble telling the difference between blue and yellow, violet and red, as well as blue and green colours. Generally speaking, everything they see seems to be red, pink, black, white, grey and turquoise.

You can also visit these websites that provide you with an online test for colour blindness.

http://colorvisiontesting.com/ishihara.htm

http://www.color-blindness.com/ishihara-38-plates-cvd-test/

To learn more about colour blindness, its causes and the different types, or to get tested professionally, speak with your eye care specialist.

If you enjoyed this post, please consider leaving a comment or subscribing to the RSS feed to have future articles delivered to your feed reader.

Leave a Reply