“Until very recent years, it was supposed by philosophers that there was a typical human mind which all individual minds were like … Lately however, a mass of revelations have poured in which make us see how false a view this is.”
—William James, 1890
As far back as the 19th century, the psychologist and philosopher William James concluded that human minds come in a variety of types. His research into psychology had shown him that each individual apprehended the world in a slightly different way, processing and coding it with a unique stamp. In his work, James was among the first to emphasize auditory, visual, and kinetic components of individuals’ inner “representational systems” as the essence of the workings of the mind.
In our own time, researchers of learning theory have reinforced James’ conclusions, stressing the importance of an individual method of internalizing knowledge — a unique blend of auditory, visual, and kinetic elements. Each person has a unique way of absorbing, processing, and coding information from the outside world with a mix of visual, auditory, and kinetic components that is not quite like any other’s.
In his autobiography, “Speak Memory,” the great 20th-century multilingual author, Vladimir Nabokov, describes his inner perception of letters of the alphabet and words:
… a French a evokes polished ebony. This black group [of letters] also includes hard g (vulcanized rubber) and y (a sooty rag being ripped). Oatmeal n, noodle-limp l, and the ivory-backed hand mirror of o take care of the whites. I am puzzled by my French on which I see as the brimming tension-surface of alcohol in a small glass. Passing on to the blue group, there is steely x, thundercloud z, and huckleberry k … I hasten to complete my list before I am interrupted. In the green group, there are alder-leaf f, the unripe apple of p, and pistachio t. Dull green, combined somehow with violet, is the best I can do for w. The yellows comprise various e’s and I’s, creamy d, bright golden y and u, whose alphabetical value I can express only by “brassy with an olive sheen.” In paler j, and the drab shoelace of h. Finally, among the reds, b has the tone called burnt sienna by painters, m is a fold of pink flannel, and today I have at last perfectly matched v with “Rose Quartz” in Maerz and Paul’s Dictionary of Color…
As Nabokov writes in “Speak Memory,” his description “presents a fine case of colored hearing”; that is, spoken words regularly evoked for him an automatic inner experience of color and texture. Nabokov’s response to language is what neuroscientists term color-lexical synesthesia, a form of perception that, over the last two decades, has been studied at universities around the world. For synesthetes like Nabokov, the color/tactile attributes perceived in letters and words remain consistent each time that word is heard, read, or thought of.
Although the phenomenon of synesthesia has been known for centuries, it is only in the last 20 years or so (since scientists developed brain-imaging technology) that synesthesia has been seriously studied. In 1995, Dr. Simon Baron-Cohen, a Cambridge University neuroscientist, headed a team that undertook brain-imaging studies of color-lexical synesthetes. Upon hearing a list of words read aloud, the synesthetes showed increased neural blood flow to a part of the brain that controls aspects of color perception (while a control group showed none). The results of the study indicated that hearing words produced a perception of color for the synesthetes.
The study of synesthesia has opened the door to the realization that each of us processes language in a unique way. Even among synesthetes, researchers are discovering a range of neural patterns for processing words and letters. Also, scientists are finding that all of us have a degree of synesthesia, from mild to strong (which is why such metaphors as “loud colors” and “sharp cheese” make sense to all of us). The study of synesthesia is helping researchers to understand the variety of ways that the human brain can process and code language.
What the Study of Synesthesia is Revealing
While in the early 1980s some researchers put the incidence of color-lexical synesthesia at one in 10 million, over the last two decades, neuroscientists such as V. S. Ramachandran, of the University of California at San Diego’s Center for the Study of the Brain and Cognition, have changed the estimate to one in 200. And even among those, there is no uniformity; color-sound perception is unique and idiosyncratic. What’s more, Dr. Ramachandran says, all of us have some experience of cross-sensory associations when processing language. The difference in processing between the one synesthete and the other 199 people may be a matter of degree and conscious awareness. Also, sensory features besides color may be prominent.
The study of synesthesia may open a dialogue that reveals the unique way that each of us inwardly experiences language and the “personal code” that we have unconsciously evolved to represent it. Since the 1970s, learning-style theorists have recognized the importance of the unique mix of auditory, visual, and kinetic elements in a given individual’s absorption of language. Learning-style testing is done to determine a student’s learning style, and teachers are encouraged to adapt their teaching methods based on a student’s individual style. However, current testing instruments have fallen short of providing insight into how language is apprehended. At present, we might consider whether an individual’s own awareness and description of his or her inner process could be more revealing — and perhaps of greater use. Could the results of any learning-style indicator have provided more insight into Nabokov’s mode of processing than Nabokov’s own description?
Synesthetic elements are common to all modes of language processing
The study of synesthetic modes of language processing may reveal something about the idiosyncratic nature of all language processing, because research indicates that all language processing contains sensory components.
It is important to understand that synesthetic perceptions do not always involve words triggering perceptions of color; they can also involve, among other combinations, sounds triggering perceptions of shapes. In his fascinating series of BBC Reith Lectures, titled “The Emerging Mind,” Dr. Ramachandran offers an example. Look at the two shapes below. Which shape is the kiki, and which shape is the booba?
Did you answer that the image on the left is the booba, the one on the right the kiki? If so, you have answered as 98 percent of the population does. But why do most of us answer like this? Because we are making a cross-sensory, synesthetic connection between sharpness of sound and sharpness of shape.
As Dr. Ramachandran explains, “Look at the kiki and look at the sound kiki. They both share one property, the kiki visual shape has a sharp inflexion and the sound kiki represented in your auditory cortex, the hearing centers in the brain, also has a sharp sudden inflexion of the sound and the brain performs a cross-modal synesthetic abstraction saying the only thing they have in common is the property of jaggedness. That’s why they’re both kiki …”