A look into the neurological condition that creates blended senses
What’s significant about the letter-number string A2R4MNKWS7Y3ELFTB5JQDPH6?
If you said “nothing,” you’re partially right. To most people, this arrangement of graphemes (a term meaning “numbers and letters”) is completely arbitrary. To me (the person who created the sequence), however, it looks like this:
Now what’s significant? Well, that’s obvious: it’s a rainbow! Usually, I’m the only one who can see that, though, thanks to a neurological condition called grapheme-color synesthesia.
The word “synesthesia” refers to the conscious, involuntary, and vivid blending of two or more modalities[1] (see next paragraph). In people with synesthesia, one modality can trigger the experience of another modality. For grapheme-color synesthetes like me, the experience of seeing numbers, letters, or characters can trigger a mental sensation of color.
Modalities are “aspects of perception[1]” that can be linked in synesthetes’ brains; some examples of modalities are smell, taste, texture, color, and sound. The reason that “modality” is sometimes used instead of “sense” when talking about synesthesia is that synesthetic linkages are often between elements that are more specific than senses. Colors and letters, for example, both fall within ‘sight’, yet are separate modalities.
About 1 in 23 people have the genes which code for synesthesia, though only 1 in 90 actually display the trait.[1] It is a hereditary condition, and people who display one subtype (such as grapheme-color synesthesia) have a 50% chance of displaying multiple subtypes.[1]
There are a large variety of different subtypes. Some synesthetes can “taste” music. Some perceive a unique texture, color, personality, and appearance for every number. And some, with a subtype of synesthesia called “chromesthesia,” associate colors and sounds.[2] For example, Annie Dickinson, a high schooler who gave a TEDx Talk on the subject of her chromesthesia, sees colored spots in her vision when she hears sounds, and vice versa. She uses her unique perceptions to create music; her first album is aptly titled Synesthesia.[2]
For people with any type of synesthesia, the linkages are consistent: grapheme-color synesthetes always see the same color for each letter or number (though the exact hue may be affected by the font, capitalization, spacing, etc. of the text) and chromesthetes always see the same color for each note or chord.
For example, to me, the word “LEFT” is an exploration of the color green: L has a delicate pale spring color, while E looks like a summer field, F is the color of young grass, and T looks like a dark forest. My “4” and “7” are a tasty orange and pale peach. And my favorite number is 256 because it looks so vibrant: bright red, royal blue, and violet-purple.
However, just because letter-color pairings are consistent for each person doesn’t mean they’re the same for everyone across the grapheme-color synesthetic community. Some commonalities do exist, but they aren’t universal. For example, 40% of synesthetes have a red “A,” and 20% have a green “H.” In general, commonly occurring graphemes tend to take on commonly occurring, saturated, and light characteristic colors.[1]
The shape of graphemes also seems to have some effect on how they are perceived; even toddlers without the ability to read usually associate “O” and “I” with white and “X” and “Z” with black, just like most adult grapheme-color synesthetes (including me) do.[1]
Synesthesia can be a remarkable memory and problem-solving aid. One of the most famous synesthetes in both the popular and psychological world was psychologist A. R. Luria’s patient Solomon Shereshevsky. Shereshevsky was more popularly known as “S,” or by a third, more evocative title: “The Man Who Could Not Forget.” Luria wrote extensively and poetically about “S” in his book, The Mind of a Mnemonist, discussing how tormented his patient was over his own inability to let go of memories of even trivial events. The real-life Solomon Shereshevsky (who did, in fact, have the ability to forget) became a performing memory expert who quickly learned lengthy strings of information for audiences.[3]
Other synesthetes are mathematical savants or musical geniuses. Daniel Tammet is one example: he solves complex mathematical problems by moving the ‘shapes’ of the numbers around in his head.[4]
“Daniel Tammet PI Palais de la découverte Paris” by De Lorelei is licensed under CC BY-SA 4.0
Clearly, having linked modalities can allow for unorthodox methods of composition or equation-solving. However, it can also lead to confusion or difficulty with things that are fairly everyday for non-synesthetes. I myself have issues trying to solve math problems involving various numbers of colored marbles, because the colors I see in the quantities and the colors of the marbles themselves usually don’t match. People with more severe and interconnected forms of synesthesia, such as Julie Roxburgh, a synesthetic music teacher living in the UK, may even have problems in noisy or colorful environments like cities, which are full of dizzying, uncontrollable, and overwhelming sensations.[1]
Synesthesia is a broad term, and its expression takes many forms; sometimes a help, sometimes a hindrance, and sometimes merely a colorful complement to life. Understanding more about this condition can help bring exposure not only to the 1% of the population who experiences its symptoms, but can also shed light on the way that we all intake and process information, create metaphors, and develop a view of the world.
References:
[1] Cytowic, R. E. (2018). Synesthesia. Cambridge, MA: The MIT Press.
[2] Dickinson, A. (2018, October 9). Seeing Sound: How Synesthesia Can Change Our Thinking. Lecture presented at TEDxYouth, Lancaster.
[3] Johnson, R. (2017, August 12). The Mystery of S., the Man with an Impossible Memory. The New Yorker. Retrieved from https://www.newyorker.com/books/page-turner/the-mystery-of-s-the-man-with-an-impossible-memory
[4] Watt, N., Strauss, E. M., & Rodrigues, A. (2010, May 28). Daniel Tammet: Mathematical Genius Visualizes Numbers, Solves Problems in Blink of an Eye. ABC News. Retrieved October 16, 2018, from https://abcnews.go.com/2020/autistic-savant-daniel-tammet-solves-problems-blink-eye/story?id=10759598
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