Colour Blindness
Habish Ribin Haneef
Colour blindness or colour deficiency is an eye disorder where you might have difficulties in realising certain colours or you can’t see them properly. A person with colour blindness usually finds it difficult to detect colours like red, green, and blue. In some rare cases, people with colour blindness cannot even detect or identify any colours. Colour blindness is seen in people in different ways. Some people with mild colour blindness can see colours normally in good light but may be having difficulty to see the same colours in dim light. Some other people cannot distinguish certain colours in any light. A person with colour blindness experiences it equally in both eyes and it remains stable throughout their lives. Some famous people with colour blindness include Mark Zuckerberg (Facebook CEO and founder), Robert Redford (American actor), George Clinton (American musician), Prince William (Prince of England, Duke of Cambridge), Christopher Nolan (English director), and Chris Rogers (Australian cricketer).
Discovery:
Colour blindness was discovered by English chemist John Dalton in the year 1798. Hence, Dalton is known as the father of colour blindness. Dalton himself was suffering from colour blindness and he wrote an article related to this topic based on his own experience. According to Dalton, he believed his colour blindness was the result of a discolouration in his aqueous humour, causing him to filter colours incorrectly. Dalton faced difficulties in distinguishing scarlet with green and pink with blue. As a result of this discovery, colour blindness is also known as “Daltonism”.
Symptoms:
Colour Blindness symptoms can range from mild to severe. People with mild symptoms sometimes do not even realise that they are suffering from this disorder.
The symptoms of colour blindness include
- Difficulty in viewing colours and the brightness of colours in the usual way
- Having trouble distinguishing between shades of the same or similar colours, especially with red and green or blue and yellow
- Rapid eye movement
- Sensitivity towards the bright light
Causes:
In the retina of a healthy human eye, there are two types of cells that detect light- rods and cones. The rod cells detect low light and the cone cells detect normal and bright light and are responsible for colour vision. Colour is perceived by three different types of cones- red, green, and blue. These cone cells provide input to the brain that determines our perception of colour. Colour blindness takes place when one or more colour cone cells are absent, not working, or detect a different colour than normal. As mentioned above colour blindness can range from mild to severe. Mild colour blindness occurs when all three cone cells are present but one cone cell does not work properly. On the other hand, severe colour blindness occurs when all three cone cells are absent or do not function in the right way.
There are many factors that can lead a person to colour blindness. These include
- Genetics- Most people with colour blindness are born with it. This condition is called a congenital condition and is usually passed from mother to son.
- Damage caused to the brain, eyes, or nerve cells
- Consumption of tobacco and alcohol
- Use of drugs
- Metabolic disease or vascular disease
- Trauma
Diagnosis:
Ophtalmologists mainly use two tests to detect whether you are having colour blindness or not. The two tests are Ishihara plate test and screening test.
In Ishihara plate test, there will be a pattern composed of multi-coloured dots. Inside these dots, there will be numbers or alphabets. If you are normal, you will be able to detect the colours and numbers or alphabets in the pattern. On the other hand, if you are not able to detect, you are in trouble.
In screening test, the type and severity of the colour blindness is determined.
Treatment:
The fact is that there is no specific treatment for colour blindness. The use of eyeglasses with contact lenses and photographic frames or filters will help you to some extent. A properly balanced diet can also help to somehow overcome the symptoms of colour blindness.
Read more:Solar and Lunar Eclipses
Check your knowledge
Answer. Colour blindness or colour deficiency is an eye disorder where you might have difficulties in realising certain colours or you can’t see them properly.
Answer. Difficulty in viewing colours and the brightness of colours in the usual way, having trouble distinguishing between shades of the same or similar colours, especially with red and green or blue and yellow.
Answer. Rods and cones