The 3 types of color blindness (and their characteristics)

We review the different typologies of this disorder in color perception.

The diagnosis of color blindness, or color blindnessAlthough it is relatively easy to detect, it often goes unnoticed for many years and only becomes apparent after a casual exposure to an Ishihara test or a typical driver's license test.

Although it may sound strange, this is what happens in a large number of cases: we do not stop to think about how we see, we simply do it and think that our color, for example, blue is the same as that perceived by other people.

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Brief definition of color blindness

Color blindness or color blindness is a disorder of genetic origin in which the sufferer does not have the same number of types of cones in his visual system or has them but they are altered.

This is because we do not have the necessary elements to capture the wave frequencies that make us capture light in the form of different colors, which is due to the sensory cells called cones.

While most people have three types of cones (one for red, one for green and one for blue) and some women have even detected four (although this is very rare), color blind people will have three, at least one of them being altered or less.

This means that we cannot capture the wave frequency necessary to capture certain colors, perceiving the stimulation under a certain frequency.and perceive the stimulation under a different wave frequency. Thus, the subject will not be able to appreciate a color and those related to it, perceiving them as if they were others.

The different types of color blindness

Color blindness can present itself in different modalities, depending on the type of pigments that are not available or that are altered. Specifically, there are three main types of color blindness, as follows.

1. Achromatism

This is a very rare condition. Achromatism or monochromatism appears when the subject does not have any pigment or the cones in question are not functional at all. Vision in this case is based on the information extracted from the cells that capture luminosity, the rods, being only in grayscale, black and white.

2. Dichromatism

Generally, when we think of someone with color blindness we tend to identify them with someone suffering from dichromatism.. This is understood as the type of color blindness caused by the absence of one of the pigment types, so that it is not possible to perceive either the color in question or the colors associated with it (for example, if someone cannot see the color red, the perception of orange will also be altered). In this case the wave frequency that allows the perception of the color cannot be captured, so the pigment that captures the closest wave frequency will perform its function, causing the colors to be confused.

Within dichromatism we can identify three basic typologies.

2.1. Protanopia

The subject cannot pick up the wave frequencies that allow seeing the color red, which has a long wave frequency. The red color tends to be perceived as beige or gray, sometimes with greenish tones. If the sling frequency is very high, it is perceived as yellow.

2.2. Tritanopia

The least common type of dichromatism, affecting the perception of short-wave frequencies. The person suffering from tritanopia does not have the pigment corresponding to the color blue, which is often confused with green. Yellows also tend to be seen as red, violet or white.

2.3. Deuteranopia

This is the most common type of color blindness along with protanopia. In this case the green pigment is missing, and cannot pick up wave frequencies of that color (which would be medium wave frequencies). Green is not picked up, generally appearing as a beige color. The perception of red also tends to be affected, having brownish tones.

3. Anomalous trichromatism

Anomalous trichromatism occurs when the person in question possesses the same three types of pigments as the majority of the population, but nevertheless at least one is altered and non-functional.. Although it is possible that they may have a slight perception of non-functional color, they need very intense stimulation to be able to capture it, being more likely that their vision is similar to that of a dichromatic.

Within this type of color blindness we can find three subtypes depending on which of the pigments is not functional.

3.1. Protanomaly

In this case, the subject is able to perceive green and blue colors normally, but red is not assimilated and captured normally.

3.2. Tritanomaly

Blue is not picked up correctly, being easy to confuse it with others depending on the wave frequency picked up. Red and green are picked up normally.

3.3. Deuteranomaly

The anomaly is found in this case in the green pigment, which cannot be perceived completely.