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Living With Colour Blindness



Colour vision problems are typically genetic disabilities which limit the ability to differentiate between shades of colour. Colour blindness is caused by a deficiency in the cones in the macular area, typically diminishing an individual's capability to distinguish between varieties of green or red, but possibly impacting the perception of other colours also.


Colour perception is dependent upon the cones located in the eye. People are typically born with three types of cones, each perceiving various wavelengths of colour tone. This is similar to the wavelengths of sound. When it comes to colour, the size of the wave is directly related to the resulting pigment. Long waves produce reds, medium-length waves are seen as green tones and short waves produce blue tones. The type of cone that is missing impacts the nature and severity of the colour blindness.


Being a gender-linked genetically recessive trait, many more males are green-red colour blind than women. Still, there are a small number of females who do suffer from varying degrees of colour blindness, specifically blue-yellow colour blindness.


Colour blindness is not a debilitating disability, but it can hinder educational development and restrict options for professionals. Lacking the ability to distinguish colours as friends do can devastate a student's self-confidence. For working people, colour blindness could be a drawback since normal colour vision is necessary for certain careers such as police officers, electricians or artists.


Eye doctors use numerous tests for colour blindness. The most widely used is the Ishihara colour exam, named after its inventor. In this test, a patient views a plate with a circle of dots in seemingly random sizes and colours. Inside the circle one with proper colour vision can see a numerical figure in a particular tint. The patient's ability to see the number inside the dots of contrasting shades determines the level of red-green colour vision.


Even though genetic colour blindness can't be corrected, there are some measures that might improve the situation. For some, wearing tinted lenses or glasses which block glare can help to perceive the distinction between colours. Increasingly, computer applications are being developed for standard personal computers and even for mobile devices that can help users distinguish colour better depending upon their particular condition. There are also interesting experiments being conducted in gene therapy to improve colour vision.


How much colour blindness limits a person depends on the variant and severity of the deficiency. Some individuals can accommodate to their condition by familiarizing themselves with substitute clues for determining a colour scheme. For instance, they can familiarize themselves with the shapes of traffic signs instead of recognizing red, or contrast items with reference objects like a blue body of water or green trees.


If you suspect that you or your child could be colour blind it's important to schedule an appointment with an eye doctor. The earlier the condition is diagnosed, the sooner you can help. Contact our North Vancouver, BC optometrists for information about scheduling an exam.