Synesthesia – What is it and how to diagnose it?
Synesthesia or Synaesthesia is a very interesting phenomenon. It is a condition of the mind resulting when the brain’s processing centers of the senses of are interconnected. People who “suffer” (or better benefit) from it, experience the world in a very different and unique way. They are called synesthetes.
So, how do these people experience their lives? They can “hear” or “taste” colors they see colored letters, they can “see” sounds and generally they perceive a sensation with more than one senses. For example, a smell can engage their vision or any other sense. They are not hallucinating they are just synesthetes.
Synesthesia is a strange mix of the senses perception which can be expressed in various forms. Some people may see the sounds, while some others may listen to the smells or they can smell drawings. According to a study of Dr. Simon Baron-Cohen, professor of psychology in Cambridge University, it is estimated that one person out of 2000 is a synesthete. The scientist and synesthete Sean Day created a list of 40 different expression forms of the disturbance. In most of them, shapes, smells, sounds and tastes acquire colors.
The first step for understanding Synesthesia was to be defined as a real perception which is stable in time and not periodical. Initially, it was believed that it had to do with memories and experiences from the childhood. According to another interpretation, when someone who is synesthete confirms that the number 5 is red and the number 7 is green, he confirms it “poetically”. However, none of these theories explains why we are not all synesthetes.
Some scientists believed that this phenomenon had a biological aspect and they decided to research the brain condition of synesthetes with the help of modern technology. Many theories trying to explain this phenomenon have been developed and are being developed as research goes on.
One interesting theory formed by the neurologist Richard E. Cytowick at ’80s. Cytowick supported that this disturbance is due to the non natural activity of the brain area which is connected with the senses. This area is the most primitive part of the human brain. According to the neurologist, all the information from the senses is concentrated to the hippocampus of the brain where they are being evaluated.
MRI (Magnetic Resonance Imaging) research confirmed that Synesthesia which is related to colors and numbers is due to the parallel activation of the V4 and neighboring areas of the brain. V4 area is responsible for processing information about colors.
When we see a specific number or letter the areas of the cortex, which are connected with the representation of the forms, are engaged. But in synesthetes the area V4 is also engaged at the same time. Scientists believe that in the brain of synesthetes there are more connections between the areas of the brain resulting to the communication of neighboring areas.
Other theories are based on the development of similar connections between different areas of the brain that are responsible for the sensory perception. For example, the center of the auditory sense is neighboring with the area of the brain which accepts stimuli from the V4 area. As mentioned earlier, V4 is related with color perception. This adjacency may explain the connections between sound and color.
The Synesthesia expression which involves taste and touch senses may be due to connections between the area of the taste and an adjacent area which controls touch. But the question of why this phenomenon is limited only to some people is still being unanswered.
Francis Galton observed that in families where there was at least one synesthete, it was possible to be other synesthetes as well. A study of some psychologists of Trinity College in Dublin was published in 2006 and showed that 42% of synesthetes have at least one first degree relative with the same particularity. Some people believe that Synesthesia is connected with a powerful gene in the chromosome X, which is transferred from mother to children. And also this is the reason that the phenomenon is presented mostly to women.
There is no explicit connection between creativity and Synesthesia. Scientists confirm that the expression of the “disease” is due to more connections between different areas of the brain. Because of these connections, senses can be triggered also from ideas or thoughts and not only from external sensory stimuli, as it was believed until now. Some people do not agree with this explanation as it has not scientifically proved.
Synesthesia is a very interesting field of research that contributes to the research of perception and consciousness. Many specialists certify that further research of this phenomenon will reveal new discoveries in the field of neurological research which is related to linguistics and metaphorical meanings.
Synesthesia Test – Try Your Senses
There are many synesthesia tests that can reveal if someone is a synesthete. A simple one is the following picture. If a normal person sees the following picture, he will not observe anything unusual.
A synesthete would likely see different letters in different colors. The next picture shows how a he would see this drawing.
Colored Numbers ?
A common expression of synesthesia is the mix of numbers and colors. The American scientists Vilayanur S. Ramachandran and Edward Hubbard created the following test in order to study this kind of synesthesia.
As you can see in the picture above there are groups of the numbers 5 and 2 in gray color. A synesthete is able to identify immediately the number 2 because he sees it in different color. The next picture shows what he would probably see.
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