Colour Blindness Simulator

Colour blindness is a condition that affects the ability to identify and differentiate between specific colours. Many doctors prefer the term ‘colour vision deficiency’ over ‘colour blindness’, since difficulties with colour perception form such a broad spectrum and most people are not actually ‘blind’ to colour (for the purposes of this article we are to stick with colour blindness as that is what most people are familiar with).

What causes colour blindness?

Many people think that colour blindness is the inability to perceive colour, when in fact – despite what the name would suggest – it’s extremely rare not to be able to see any colour at all and there are many different types of colour blindness.

Sometimes the condition is so subtle that people don’t even realise they are affected. If you are concerned that either yourself or a loved one may have problems with colour perception, the test below and this article will help you understand the condition and think through your next steps.

Colour blindness is a condition that affects the ability to identify and differentiate between specific colours. Many doctors prefer the term ‘colour vision deficiency’ over ‘colour blindness’, since difficulties with colour perception form such a broad spectrum and most people are not actually ‘blind’ to colour (for the purposes of this article we are to stick with colour blindness as that is what most people are familiar with).

What is colour blindness?

Colour blindness can either be a condition you’re born with or one that develops later in life. In order to manage and treat it most effectively, it’s important to know the underlying cause which could be down to genetics or develop as a symptom of another underlying health issue.

Inheritance

In most cases, colour blindness is inherited and much more prevalent in men than women. It results from a genetic fault meaning the cells in the eye that are sensitive to colour, called cones, are either missing or defective. Interestingly, hereditary colour blindness normally affects boys more than girls.

Acquired

Sometimes colour blindness presents later in life, as a symptom of an underlying health issue such as:

• Multiple sclerosis
• Diabetes
• Glaucoma
• Muscular degeneration

It can also be triggered by certain medications or chemical exposure.

If you start to experience difficulties with colour vision, you should visit your doctor. The good news is that acquired colour blindness may resolve once the underlying medical condition is treated.

How do we see colour?

Inside our eyes, we have a layer of tissue known as the retina, which is made up of cells called rods and cones. These cones contain a pigment that is sensitive to colour. The colours we see are the result of these pigments and the genetic code that instructs them – if there are mistakes in the genetic code, we see the wrong shades of colour.

Colour Blindness Statistics

Colour blindness can be worrying – especially if it’s a new experience, or you feel your colour vision deficiency is getting worse. To calm your nerves, it may be helpful to take a step back and look at the issue in its wider context; these statistics about colour blindness may give you some perspective:

• Only 25% of people see colours exactly as they are.
• In the UK, approximately 2.7 million people are affected by colour blindness.
• About 95 percent of colour blindness affects the perception of red and green colours
• This “red-green” colour deficiency affects around 1 out of 12 men and 1 out of 200 women.
• The complete inability to see colour (known as monochromacy) is extremely rare, affecting less than one in 30,000 people worldwide.

Types of tests

In order to know for sure whether you are affected by colour blindness, you’ll need to have a diagnostic test. There are different types of test, but the most common ones are:

The Ishihara test

Here you will be shown images consisting of different coloured dots and asked which numbers you can pick out within the image.

The colour arrangement test

For this test, you will be asked to arrange coloured objects according to their shade.

Are there treatments for colour blindness?

If your colour blindness is caused by an underlying medical condition, there’s a good chance that your vision will improve when you treat the condition.

For inherited colour blindness, though, there is currently no known cure. Nevertheless, there are plenty of ways to minimise its negative impact on your life. Such as:

Use technology

There are some excellent smartphone apps that help with the identification of colour. Some name the colour, others adjust the colour so you can recognise it.

Consider using specially designed glasses or contact lenses

It is possible to buy tinted glasses or contact lenses that help you distinguish between certain colours – ask your optometrist if you don’t know where to find them.

Speak to your child’s school

If it’s your child that’s diagnosed with colour blindness, you can ask their teachers to adapt their learning materials so their schooling experience doesn’t suffer.

How does colour blindness affect daily life?

The extent to which your colour blindness affects your life depends on the type and severity of your colour vision deficiency. For people living with milder forms of the condition, it often has minimal effect on their day-to-day. Others need to use conscious strategies to manage everyday tasks such as driving, cooking and shopping.

If you would like to learn about strategies for managing colour blindness, there are some excellent resources available online. It can also help to connect with other people in your area with the same diagnosis.

What research is being done?

If you or someone you love is affected by colour blindness, you will be encouraged to know that there are some promising new treatments in the research stages.

For example, scientists are exploring gene therapy as a possible cure for colour blindness; one study successfully treated colour blindness in monkeys using this method. What’s more: there is hope that an injection may be developed in the future, using the principles of gene therapy, to treat colour blindness in humans.

What to do if you think you may have colour vision deficiency

If you’re concerned about colour blindness, you should start by taking a test to find out for sure whether or not you’re affected.

Remember, the sooner you know what’s going on, the sooner you’ll be able to get it under control. Either by seeking the medical treatment you need, and/or by adopting the necessary coping strategies, to help you feel more in control of your colour vision.

This simulator has been produced by LESH who produce comprehensive information on eye conditions, laser eye surgery.