eyes-of-the-colourblind-blog

[eyes-of-the-colourblind-blog]

The Island of the Colorblind

An island in the South Pacific called Pingelap Atoll has an interesting genetic occurrence, which is why it is more commonly referred to as the Island of Colourblind. Oliver Sacks explored this phenomenon in his book titled The Island of the Colorblind, which is how we were first introduced to it. As ominous as it sounds, the history dates back to 1775 when a typhoon created a population bottleneck or large decrease in the number of inhabitants. The ruler survived and the nickname of the island can be traced back to him. He was the carrier of a gene that resulted in an extreme type of color blindness called achromatopsia (seeing in shades of grey). Now, ten percent of the population lives with this condition. However, achromatopsia is so rare that it is found in one in 30, 000 people in other places of the world.

The Work of Sanne De Wilde

In 2015 after a visit to the island, De Wilde used her background in photography to curate images using infrared lenses and adjusting photo settings to depict the outcome of living with this condition. Her photographs allow viewers to see the world through the eyes of the colourblind. Some images are black and white, while others have hints of reds to showcase different types of colour blindness. She also invited individuals to colour over her black and white photographs using watercolours despite being unable to identify what colours they were using. This gave a unique perspective. We will also be providing a link to a video including her works and are presenting some photos as well.

Colour vision deficiency contributes to difficulty in identifying and/or distinguishing between an array of colours or shades; opposed to total colour blindness which is the inability to see colour overall. However, as a medical condition to which many individuals live with, its impairments  can be a strain, as it is not taken account for in society. It can impede their aspirations as some careers, such as becoming a pilot, require successful completion of a colourblind vision test day to day life. Moreover, in everyday life, colour coded information, such as street signs and educational visuals, impair an individual’s ability to navigate the world. However, this is an inspirational makeup artist that was able to learn about colour and makeup with the help of her colleagues. At the end of this article, we will provide the video that expresses her talents and her tips!

Defining Colour Blindness 

The retina has two types of cells that helps in detecting light which are known as rods and cones. Rods are able to perceive only light and dark and are very sensitive to low light levels, while cone cells recognize color. There are three types of cones that see color: red, green and blue. The brain uses input from these cone cells to determine our color perception.

Individuals with the colour blindness have cone cells which are absent, not functioning, or unable to distinguish different hues. Typically, most primates are trichromats, which means that they have three colour vision photopigments. Other mammals are classified as dichromats and have two colour vision photopigments. Even surprisingly, Some birds, fish, and reptile have four photopigments allowing them to see ultraviolet light that is invisible to humans! Most often individuals with colour blindness are unable to fully identify red, green or blue light, as they have dichromatic colour vision (only two types of cones). They are not blind, rather, they tend to see colours in in a limited range of hues.  

Symptoms 

Symptoms/clues of colour blindness are usually detected first by parents at a young age. In some rare instances, these symptoms can go undetected, as they range from mild to severe. Some clues include:

Using a wrong colour for unambiguously coloured objects (e.g., using purple for the sun) 

Difficulty reading coloured worksheets 

Inability to tolerate bright lights 

Poor vision 

Inability to distinguish between shades, including similar shades (happens most with red and green and blue and yellow) 

Trouble with the brightness of colour 

Inability to see colour at all (see different shades of grey) 

Diagnosis 

Colour blindness is commonly diagnosed during early children with screening tests, such as the Hardy- Rand- Rittler (H-R-R) or Ishihara Colour Plates. The individual is told to identify coloured shapes or numbers that are surrounded by dots. The tests vary in colour and intensity. A physicians will evaluate the type of colour blindness and the level of colour deficiency.

Ishihara Plates - 

The most common testing method for assessing colour vision is known as Ishihara plates. They are used for colour perception tests specifically aimed at those with red-green colour deficiencies. The plates in the test are based on the “pseudo-isochromaticism”, which describes the effect of two or more colours that appear at the same time, when they are very distinct independent colours. The intention for the use of this test was to have results that were easily interpreted, therefore making it more reliable. However, there are many critiques of this method.

Here as some examples: 

As you can see, the circles contain dots of different sizes and shades of different colours, which would be similar to camouflage. Ishihara plates have four ways that portray the different shades of colours to test the identification of colours –

Transformation Plates: those with defective colour vision should see different figures than those with normal vision; this is because of the different hues of colours that are used for the numerals that overlap vs those that do not.

Vanishing Plates: only individuals with normal vision can see the figure

Hidden Digit Plates: only individuals with a colour vision defect can see the figure

Diagnostic Plates: to determine the type of colour blindness the individual has and the level of it, for example it would measure protanopia or deuteranopia

Types of Colour blindness 

Overall, there are five types of colour blindness, which include –

Anomalous Trichromatic: This is when individuals are able to see colour to some extent as mostly all three of their cones can perceive light colours. One of their cones permits them from perceiving light slightly out of alignment. There are three subsections of this colour blindness: 

Protanomaly: have a reduced sensitivity towards red light.

Deuteranomaly: have a decreased sensitivity to green light

Tritanomaly: have a dropped sensitivity to blue light.

Protanopia Colour blindness: This is when individuals have adversity in perplexing black with several red colours. Such as, dark brown with dark green; dark orange and dark red; some blues with some reds; purples and dark pinks; and, mid-greens with some oranges.

Deuteranopia Colour blindness: This is when individuals have difficulty differentiating with mid-reds and mid-greens. Such as, blue-greens with grey and mid-pinks; bright greens with yellows; mid-reds with mid-brown; light blues with lilac.

Tritanopia Colour blindness: This is when Individuals confuse colours. Such as, light blues with greys; dark purples with black; mid-greens with blues and oranges with reds

Monochromacy or achromatopsia Colour Blindness: This is when no colour can be seen and is considered to be fully colour blind. With this type of colour blindness, the individual only sees various shades of grey ranging from black to white. 

Seeing Colour: Theories 

The component theory was proposed by Thomas Young in 1802 and revised by Hermann von Helmholtz in 1852. It states that we have three kinds of colour receptors (cones), and that each has a different spectral sensitivity. The colour of a specific stimulus is determined by the ratio of activity in the three cone. This is done by mixing together three different wavelengths of light in different promotion creates any colour of the visible spectrum.

The opponent process theory was proposed by Ewald Hering in 1878. According to this theory, there are two different classes of cells in an individual's visual system – class one: encoding colour and class two: encoding brightness. Cone photoreceptors are linked together to form three complementary colour pairings (blue/yellow, red/green, and black/white). The activation of one colour in the pair inhibits activity in the other. No two colours from the complementary pairing can be seen at the same time (e.g., we can not see bluish yellow or reddish green). People with dichromatic deficiencies are able to match a test field using only two primaries. Depending on the deficiency they have, they will confuse either red and green or blue and yellow.

With colour constancy, it is followed that the perceived colour of the object is not as simple as the functioning of wavelengths reflected by it. An object stays the same colour despite major changes in the wavelengths of light that it reflects An advantage of this would be that the colour doesn’t change every time there is a change in illumination.

Finally, the retinex theory of colour focuses on the reflectance of items, which would mean the proportion of light of different wavelengths that a surface reflects. This theory follows that this is what determines the colour of objects we see. According to this theory, our visual system perceives colours through reflectance of surfaces and then through the comparison of light from an adjacent surface in different wavelengths (short, medium and long). The theory is crucial for neuroscientists and their discovery for mechanisms used in colour vision because it suggests how some neurons involved in colour work. Land’s theory also states that the colours we see are constant, so green objects are green, blue objects are blue. 

Treatments

In most cases, colour blind or colour deficient individuals can benefit from technologies, such as using colour filters from apps. Optical assistant devices, such as enchroma glasses and the wearable improved vision system for colour vision deficiency device also aid in enhancing brightness between some colours. Gene therapies are also being observed to create an additional photopigment, thus, creating trichromatic vision. However, currently there is no cure for colour blindness. The following images have been edited using a filtering app that alters images to make colours easier to see for those with colour blindness and is inclusive to the different types. You can access more images under our gallery tab and we have provided information about the app in another tab as well.

Here is our original photo:

Now, here are some with the filters from the app NowYouSee. This filter helps recognize green by substituting with different colours that can be distinguished by those with deuteranopia

This filter helps recognize blue by substituting blue with different colours to help those with tritanopia

Here’s a cool podcast you can listen to! If you find this interesting, you can read about more scientific research by clicking the tab at the top of our page.  

Facts 

Being completely colourblind means you see the world in black and white, most colourblind individuals see some colours but cannot distinguish between certain colours, like red and green

Did you know that some animals are actually colourblind? Animals like dogs, cats and rabbits have a high chance of being colourblind and seeing the world through grey shades. However, others like butterflies see more colours than humans.      

Colourblindness can affect cooking abilities and it is found that those with red-green colourblindness have a hard time telling if their meat is cooked through

It is possible to be colourblind in one eye (really rare!) and is known as unilateral dichromacy 

Colour blindness is more frequent in males than females; 1/12 males suffer from a degree of colour blindness, whereas 1/200 females are affected