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I Smell Something You Can't See

Ina Rottscheidt (ncy)December 11, 2004

Tuesday is red, the sound of a soprano hitting a high note is green. Seeing tones and words in color are some of the things that people with the rare gift of synaesthesia experience.

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Synaesthesia: Can you see the sound of airplane noise?Image: Gesellschaft zur Förderung angewandter Informatik

Jana Schneider and her classmates knew something was different about her on their very first day in school. "Four plus four is red," she declared to the laughter of her peers. Eight was red for Jana, and it still is. For photographer Jonas Merk the sounds of trumpets are yellow and saxophones play purple.

Jana and Jonas are merely two of an estimated 100,000 synaesthetes in Germany. In addition to normal perception caused by sensory stimuli this phenomenon automatically sets off an additional sensation. Synaesthetes taste shapes, sees smells or hear colors, the latter of which is most common, as Prof. Henning Scheich from the Leibniz Institute for Neurobiology in Magdeburg explained.

Tuba Bläser auf dem Trachten- und Schützenumzug anlässlich des Münchener Oktoberfestes
Purple to someImage: AP

Synaesthesia can't be explained away as the makings of active imaginations. "In genuine synaesthetes, that is, those who from childhood have possessed this sense, the connections are fixed," Scheich said.

Scheich will often read lists of hundreds of words to his test subjects, and months later they again describe the exact same perceptions they connect to the individual words. "People simulating don't manage to do that. That's how we differentiate synaesthetes and people who just use free association."

So far science hasn't yet been able to explain the phenomenon. "There's the hypothesis that synaesthetes retain nerve connections normally lost after babyhood," Scheich explained. Synaesthetics researcher Hinderk M. Emrich from the Hanover Medical School has described the phenomenon as a "short-circuit in the head."

Pepper sauce tastes like triangles

Musik im Kopf
Hyperfunction of the brain?Image: Christian Gaser

Theoretically, any combination of melding senses is possible. "The letter 'a,' for example, is blue to one person, a high C smells like lemon to another and to a third pepper sauce tastes like pointy triangles. It's highly individual," Markus Zedler from the Hanover Medical School explained. He described the phenomenon as a "hyperfunction of the brain." Different areas of the brain are connected in such a way that stimuli that would normally be repressed are caused in the consciousness.

A similar thing happens to people who aren't synaesthetes but take hallucinogenic drugs. "Stimulus satiation or delusions as in drug abuse, however, are virtually unknown in synaesthetes," Scheich said.

But Scheich and his colleagues don't view the phenomenon as an illness. On the contrary: "Many test people can take note of things more easily because they virtually store the things twice," Zedler said. Thus, many synaesthetes are particularly good at remembering figures since they see numbers as colors.

Hard being different

"Often though synaesthetes experience severe psychological because they aren't taken seriously by others and are laughed at," Scheich has been told by those affected.

Improvisation VII
Vasily Kandinsky, Improvisation VII, 1913

"When I told my best friend her name sounded dusky pink, my relatives wanted to send me to a psychologist," synaesthete Sabine Schneider recalled. But now the educational theorist is proud of her ability, even competing her PhD on the subject.

And Schneider may one day join the ranks of famous creative synaesthetes, along with musician Blixa Bargeld, composer Jean Sibelius and artist Vasily Kandinsky. The Russian painter is said to have hummed the tones of colors before he mixed the paints on his palette.