Title: Why can't men dress themselves?
Author: Martin Drinkwater
Category: Cool Science


Ever wondered why men can’t seem to colour co-ordinate their clothes? Perhaps they are colour blind.

In the retina at the back of our eyes, there are millions of cone cells. The cone cells have three different pigments, each of which is a type of amino acid. 

When you look at an object, the colours that you see are those being reflected from the object. Much of the light in the visible spectrum is absorbed in objects around us, though, rather than reflecting. When a small portion of the reflected light hits a pigment in your eye, it is converted into an electrical signal. The signal is carried through nerves to the brain so that we perceive the light as being a mixture of red, green and blue. The colours that we see depend on this interaction between the eye and the brain. Like radio stations, each colour corresponds to an exact frequency of light.

What happens then if the brain receives the wrong signal? As with static, which represents errant signals on the radio, colours in the eye can appear distorted. Consistent distortion occurs for those with colour blindness. People who are colour blind have missing or abnormal pigments, making them 'colour deficient'. Colour deficiency results in them being sensitive to light of different frequencies than those associated with 'normal' vision. So, might see a common colour as some colour different to what others see, and they may lose the ability to distinguish between colours.

Take a look at the picture. Those with ‘normal’ vision will see the number 35. People suffering from colour vision deficiency will only be able to see either the 3 or 5. Ishihara test for colour blindness

The most prevalent form of colour vision deficiency is "Red-Green". People with this condition are not blind to colour; they just see red and/or green as different things. For example, a red traffic light might look orange, green grass may become indistinguishable from brown.

Other forms of colour vision deficiency can also occur, as well as problems with light sensitivity. Total colour blindness (where vision is in monochrome, meaning black, grey and white) is extremely rare, affecting only about three in every million people.

There are a number of tests for colour vision deficiency. One of the most common is the Ishihara test, which relies on being able to distinguish numbers from a coloured background.

Take a look at the picture. Those with ‘normal’ vision will see the number 35. People suffering from colour vision deficiency will only be able to see either the 3 or 5.

Colour vision deficiency is a genetic disorder. It affects one in 12 males compared to about one in 250 women. Perhaps, this difference goes some way to explaining why males have a reputation for being unable to colour coordinate their wardrobe. Colour vision deficiency is found on the X-chromosomes, so you actually inherit it from your mother. The condition is also far more prevalent in European Caucasians than in any other ethnic background. Who said being a ‘white male’ was easy?