The History of Synesthesia

History of Synesthesia

Synesthesia is the crossing of two neural pathways which causes one sense to be activated unconsciously when another was consciously activate. The Greek meanings of the word are Syn (union) and aisthesis (sensation); put together for the union of different sensations. Synesthesia is a phenomenon which has been boggling researchers for over three-hundred years. While it has been known in the world for such a long time; there is still little to no research which has been successful in answering the age old question of why and how synesthesia occurs in the brain (Harrison, 1995). This is due to the primary source of data on the phenomenon is people who claim to have experienced synesthesia themselves; which leaves researchers with one-hundred percent subjective data, versus the objective data they need to draw the conclusions they need.

There are many different types of synesthesia which have been discovered. Some of which are more commonly known, but actually less common in the world. Different types of synesthesia include: Grapheme-color synesthesia,
 Chromesthesia, Spatial sequence synesthesia, Number form, Auditory-tactile synesthesia, Ordinal linguistic personification, Misophonia, Mirror-touch synesthesia, Lexical-gustatory synesthesia, and Spatio-temporal synesthesia. There are many more types of synesthesia, however, there is not much research done to explain how they work at this time (Novich, 2011).

The most common form of synesthesia which is known is grapheme-color synesthesia. This is the association between letters or numbers and colors. Such as when a person with synesthesia hear the letter “L” they would think of a specific color. Each letter and number have an assigned color to them and they do not change as the person with synesthesia grows older (Novhich, 2011).

One of the most widely known forms of synesthesia is actually one of the most rare forms of synesthesia to be truly experienced by a person. This form is known as chromesthesia; which is the association of a color with sounds which are heard by the person. It is mostly done with music, however, there are cases of people experiencing colors with everyday sounds, such as car doors closing (Novich, 2011).

Another rare form of synesthesia is known as mirror-form synesthesia. This is when a person thinks that they can feel on their body what a different person is feeling on their body. An example of this is when a person observes another person being tapped on the knee, they then believe that they can feel someone tapping on their knee at the same time. Someone who has this form of synesthesia has been showed to have higher levels of empathy in their body compared to the general public. This is due to the mirror neurons which are present in the motor areas of the brain, which are linked with empathy (Novich, 2011).

In order to make an attempt to make synesthesia be more understood by others, Ox compares it to the phenomenon of absolute pitch. The comparisons between the two phenomenons are that one can either be born with it; or can attempt to train themselves to have the skill. However, it has been shown that one cannot really learn to have synesthesia, only teach themselves associations between the senses. Such as always associating a certain letter with a certain color, this may not be synesthesia, it could just be a person who has always thought of that color because of a certain memory. This compares with a person “training” themselves to have absolute pitch because even if they were to acquire absolute pitch throughout their life, it would not be as strong and would actually be referred to as relative pitch instead (Ox, 1999).

Ox went on in his research article to say that it could indeed be possible to forge new pathways in one’s brain which connected senses together, but there is still no evidence proving that it can be done at this time (Ox, 1999). However, he does go on to explain how we all experience synesthesia in our lives with poetry. Due to the way which the author writes their poems, they all seem to have a “melody” which they follow. This causes the person who is reading it to “sing” the poem and almost feel as if they were creating music. While this is not actually synesthesia, it is probably the closest thing those who do not have synesthesia can get to experiencing it in our lives without the use of hallucination inducing drugs (Ox, 1999).

While it will not be true synesthesia, Ox and his colleagues encourage anyone who has conducted research in the field of synesthesia to send their work in to their publishing company, Leonardo. They are looking for research done on the topics of art and synesthesia; either the exploration of a person who has true synesthesia or on research of how to make human-made synesthesia; this is where equivalences have been made between different forms of media and are also carefully calculated. The researchers at Lenardo are hoping to uncover a new way in which we can explore this widely unexplored phenomenon (Ox, 1999).

A Biological Explanation?

In the history of studying synesthesia, researchers thought that there had to be a biological explanation for the phenomenon. While many studies show that synesthesia is a hereditary trait, which therefore makes it a biological component of a person; a study conducted by Paulesu et al. proves otherwise. Paulesu tested to see whether or not there was an increase of rCBF in the limbic areas of the brain. The study’s results showed that there was no increase in rCBF in the limbic areas of those who claim to have synesthesia. Therefore, there is still no biological explanation for synesthesia to be occurring at this time (Harrison, 1995).

First Known Account of Synesthesia

Georg Tobias Ludwig Sachs provides us with what is probably the first ever medical account of synesthesia, which is based on observations of himself. His case was widely cited in the medical literature of the nineteenth century, but is not well known by contemporary researchers due to their being no English translation of his work (Jewanski, 2009). Sachs published this work in 1812; it mostly discussed his albinism as well as his sisters albinism; but he also touched on the topic of synesthesia. Sachs research suggests that there is a different structural organization in the white matter of the brain in a person who has synesthesia; this would give researchers the evidence they need to make sense of the subjective information they have been provided with thus far in their research. Unfortunately, due to researchers not having access to his study until recently, no further research has been conducted in order to continue on the researcher’s work (Jewanski, 2009).

Jewanski went on to discuss how even if Sach’s research showed to not be the actual first case of synesthesia which has been documented, his research is fascinating and worth the read. Jewanski then went on to talk about “pretenders” which tried to also say that they were the first case of synesthesia in the world. There are four other cases which have been claimed this; three of which were all blind people who said they could still experience colors, and a fourth who is said to most likely be the person who invented the color-music correspondence which is now commonly known as chromesthesia (Jewanski, 2009).

Testing for Synesthesia

Researchers have come to no clear consensus when it comes to finding a way to test for synesthesia. Researchers agree that we must establish the presence of synesthesia before we can set a baseline for measuring synesthesia and experimentation with synesthesia. There needs to a method in which identifies the information which is being derived form one sense modality to the modality of another (Harrison, 1995).

One study which attempted to measure synesthesia was conducted by Baron-Cohen. The researcher studied how those who claim to be synesthetic assign each word they were told to the color which they “saw” in their brains. Baron-Cohen found after this study that the color-correspondence done in this study was unreliable due to the subjects being told to assign the colors based on the component letters in the word versus Baron-Cohen’s later study which told the participants to assign the color to the word depending on the dominant letter, or the first letter, of the word.

Famous Figures

Throughout history, there have been many famous figures who have claimed to have synesthesia. Many of these figures are in the creative field of work; poets, artists, and musicians. Some of which even claim that the synesthesia is what allowed them to create their pieces of work. A quote from Vassily Kandinsky explains his experience of synesthesia and what he feels in really happening while he is composing his music, “ The violins, the deep tones of the basses, and especially the wind instruments at that time embodied for me all the power of that prenocturnal hour. I saw all my colors in my mind; they stood before my eyes. Wild, almost crazy lines were sketched in front of me. Vassily Kandinsky (1913, p. 364).” (Ione, 2004).

In his article, “What Do You Care What Other People Think?,” Feynman (1988, p. 59) claimed, ‘‘When I see equations, I see the letters in colors.’’ To composer Alexander Scriabin the key of F# major appeared violet in color (Myers, 1914). Writer Vladimir Nabokov noted in his autobiography Speak, Memory (1947, p. 21), ‘‘[t]he long ‘‘aaa’’ of the English alphabet has for me the tint of weathered wood, but a French ‘‘a’’ evokes polished ebony.’’ And composer Oliever Messiaen waxed lyrical about ‘‘the gentle cascade of blue-orange chords’’ in one of his pieces (Bernard, 1986). (Ione, 2004).


Harrison, J., & Baron-Cohen, S. (1995). Synaesthesia: Reconciling the subjective with the objective. Endeavour, 19(4), 157.

Ione, A., & Tyler, C. (2004). Neuroscience, History and the Arts Synesthesia: Is F-Sharp Colored Violet?. Journal Of The History Of The Neurosciences, 13(1), 58–65.

Jewanski, J., Day, S. A., & Ward, J. (2009). A Colorful Albino: The First Documented Case of Synaesthesia, by Georg Tobias Ludwig Sachs in 1812. Journal Of The History Of The Neurosciences, 18(3), 293–303. doi:10.1080/09647040802431946

Novich, S., Cheng, S., & Eagleman, D. M. (2011). Is synaesthesia one condition or many? A large-scale analysis reveals subgroups. Journal Of Neuropsychology, 5(2), 353–371. doi:10.1111/J.1748–6653.2011.02015.x

OX, J. (1999). Color Me Synesthesia. Leonardo, 32(1), 7.