For people with synthesthesia, sound has color and music has shape

By Lisa Marshall, Camera Staff Writer
December 14, 2003

To Massachusetts photographer Marcia Smilack, the image of light reflecting on water makes an almost deafening musical crescendo.

To New York painter Carol Steen, pain appears orange.

To Boulder poet Clara Burns, a year is an exaggerated oval, a "bent race track," and each month is a colored rectangle within it.

Confused?

While these may sound like mere metaphors hatched in the fertile imaginations of artists, they are in fact true sensory experiences, says psychologist Peter Grossenbacher, head of the Consciousness Laboratory at Naropa University and one of the nation's leading experts in synesthesia.

The little-known neurological trait ≈ only recently acknowledged as real in the scientific community ≈ causes as many as 1 in 300 people to have their perceptual wires crossed, leading them to respond to outside stimuli with one sense instead of or in addition to the expected one. Some so-called "synesthetes" literally see sounds and hear colors. Others taste shapes and feel images. Many, like Burns, perceive time as having shape and numbers and letters as having their own specific colors.

"For them, the experience is so real. A scent may be smelled and heard. It has its own loudness, pitch and timbre. Or the sound of an electric guitar may induce one specific color," says Grossenbacher, who has a Ph.D. and spent five years studying synesthesia at the National Institutes of Mental Health before coming to Boulder three years ago.

While reports of "colored hearing" and "colored letters" date back to the early 1800s, synesthesia was long written off as the product of artistic fancy, psychedelic drugs or madness. But in the past decade, thanks to brain scan technology that now allows scientists to spy on the brain as it experiences the senses, researchers have begun to acknowledge that the condition may be real and investigate what causes it.

Perhaps, some researchers say, the brains of synesthetes are structurally different, with portions of the brain that control color signals and hearing, for instance, so close together that signals intended for one area hit both. Or perhaps, as Grossenbacher thinks, people have the same basic neurological wiring, but in most of us, hormones keep us from experiencing those extra sensory perceptions so we don't get confused.

"There are people who never experience synesthesia until they take LSD," he notes. Because people don't suddenly grow new anatomical connections in their brains when they take drugs, he's convinced we all have the same neurological connections, but for some reason synesthetes use theirs more fully.

The trait is worth studying, researchers say, because it may offer insight into why some people are naturally more artistically inclined or more easily overstimulated than others. And perhaps, some theorize, those who lose one sense due to a brain injury may be able to compensate through synesthesia.

For those who have it and never knew it had a name, the brewing interest has been a blessing because it has brought them together.

Being different

"People with synesthesia just think that everyone is perceiving what they are perceiving until one day, they say something by accident and they realize that is not the case," says Pat Duffy, co-founder of the American Synesthesia Association and author of "Blue Cats and Chartreuse Kittens; How Synesthetes Color Their Worlds," (Henry Holt; 2001) "It can make you feel kind of strange and alone."

To Duffy, the letter A has always been orange in her mind's eye and the letter C has always been blue. Time has always had shape and color.

It never dawned on her that others didn't see things the same until age 16, when she was reminiscing with her dad about when she was learning to write the letters P and R.

"I said to my father, 'I was so surprised that I could turn a yellow letter into an orange letter just by adding a line," she recalls.

Understandably, he was puzzled.

Years later, she came across an article written by one of Grossenbacher's colleagues, and learned that her visions of colored numbers had a name.

Soon, she was seeking out other synesthetes around the country so she could share their story in a book.

Steen was one of them.

The New York painter and sculptor was 7 when she first realized she may be different.

"I was walking home from elementary school in Detroit and I turned to my girlfriend and said, 'You know, the letter A is the prettiest pink I've ever seen," recalls Steen. "She gave me one of those withering looks and said, 'You are really weird.' I didn't say another word about it until I was 20. I didn't want to be weird."

In 1995, she helped Duffy found the American Synesthesia Association.

It now has 150 members and has held several national conferences at prestigious universities.

Steen, known for her vivid paintings of the color of touch, now lectures and writes academic papers about her experiences as a synesthetic artist. The ASA Web site serves to bring synesthetes from across the country together.

"It has completely shaped my life, now that I know I have it," Steen says.

Artistic link

So far, research has shown that synesthesia is hereditary, and more common among women and children. But new research is suggesting another not-so-surprising trend. It is far more prevalent among artists.

Out of 84 synesthetes Grossenbacher interviewed this fall for a study, 26 turned out to be professional artists, writers or musicians and 44 spent much of their free time pursuing the arts.

Another study, cited in an April article in Scientific American found that the condition was seven times more common among artists than in the general public:

"Our insights into the neurological basis of synesthesia could help explain some of the creativity of painters, poets and novelists," wrote Vilayanur S. Ramachandran, director of the Center for Brain and Cognition at the University of California at San Diego.

In her book, Duffy points out that many famous artists over the centuries have touted themselves as synesthetic:

Nineteenth-century French poet Arthur Rimbaud wrote about seeing colored vowels; Russian writer Vladimir Nabokov described his own colored alphabet in his autobiography; composers Frank Liszt and Olivier Messiaen both reported seeing colored musical notes. Painter David Hockney paints with the colors he sees when listening to music.

"It makes sense," says Duffy. "You have this very active inner life, and you want to express it."

Massachusetts photographer Marcia Smilack says she could not practice her unique art without her synesthesia.

"I consider it a gift. Everyone I have ever known considers it a gift," she says.

She has a doctorate in English literature but earns her living as a "reflectionist" photographing almost exclusively reflections on water. When the light hits the water, she literally hears music.

"I shoot when I hear a chord of color," she says.

Scientific evidence

While such stories may seem hard to believe, modern science is beginning to lend credibility to them.

At last month's Society for Neuroscience meeting in New Orleans, researchers from the United States and Europe shared their recent findings on synesthesia.

In one study a team of scientists at Oxford University interviewed people who said they had experienced colored hearing all their lives. They were asked to describe what colors they saw when hearing the names of each day of the week, month of the year, and letter of the alphabet and of several numbers between one and 100. Two months later, they were surprised with another, identical pop quiz.

Their answers were, for the most part, the same.

"This is strong evidence that they were experiencing a genuine phenomenon. They actually appeared to be seeing colors in their mind's eye," said Megan Steven, the lead author of the study, in a prepared statement. Even more impressive: the subjects had all been blind for at least 10 years.

In another study, which Ramachandran describes in the Scientific American article, synesthetes were asked to look at a set of black 2s in the shape of a triangle, hidden in a sea of black 5s. To most viewers, it would be hard to distinguish the 2s from the 5s and the black-and-white sea. But for synesthetes, for whom 2s and 5s are different colors, the triangle of 2s popped out immediately.

In another experiment using brain imaging techniques, synesthetes presented with a sequence of numbers showed activity in not only the portion of the brain that processes numbers, but also the one that processes color.

And the researchers are just getting started, Grossenbacher says.

He has been in contact with more than 400 synesthetes across the nation and hopes to interview as many as possible.

He says better understanding the trait may help prevent those who have it from being misunderstood.

"I had one woman who, as a teen, was sent to drug rehab after a teacher overheard her describing something she had seen," he said. Another was placed on medication to treat what her doctor perceived as hallucinations.

Duffy is delighted to, at last, be connecting with others like her around the country.

But she thinks her neurological quirk is just one example of how differently human beings ≈ synesthetic or not ≈ can perceive the world around them.

"Anytime any of us looks at the world, we are seeing it as no one else has seen it before. We are seeing it through a lens that no one else," she says. "Maybe synesthesia just gives us a very concrete example of that."