How can synaesthesia help us better understand the neurological basis of metaphor, what kinds of art does synesthesia inspire, and what might synesthesia tell us about creativity?
As Ramachandran and Hubbard pointed out in 2001, metaphors often take the form of cross-sensory associations such as “loud tie,” “cool jazz”,”sharp cheese”, “sour note”. But why do we have such synesthetic turns of phrase and why is their meaning so readily obvious? For example, when we describe people as “sweet”, we do not literally mean that if we were to lick them like an ice-cream cone they would taste sweet. Rather , we mean they are pleasant and agreeable the way sweets are.
We already indicated that syntesthetes and non synthesthetes both make matches in ways that are similiar. The work of Larry Marks and others unmasks systematic and lawful correspondences among sensory dimensions such as size, pitch, lightness, loudness, visual position and shape. For example louder tones are brighter than soft tones, higher ones are smaller and brighter than low ones, and low tones are both larger and darker than high ones. Even smell maps to bright-dark and high-low dimensions, the relation between color, light-ness, and odor intensity being well known to both psychologists and chefs: For example, people agree that a darkly tinted liquid smells stronger than when it is pale. A darker color also makes them say that the taste is stronger.Dance was another example we gave of cross-sensory mapping in which body rhythms effortlessly correspond to sound rhythms both kinetically and visually.
Consider the following experiment first conducted in 1929 among different cultures. When speakers of various tongues are shown the two shapes one looking like a jagged shard of broken glass, and the other like an amoeba blob, and told that in some alien language one of the shapes is called “bouba” and other “kiki”, 98% pick the spiked shape as “kiki” because its visual jags mimic the “kiki” sound and the sharp tongue inflections against the palate.
This kind of correspondence across culture illustrates the rule that pre existing relationships(analogies) are often co-opted in biology. In this way synesthetic associations our ancestors established long ago grew into the more abstract expressions we know today – and this is why metaphors make sense. Orderly relationships among the sense imply a cognitive continuum in which perceptual similarities give way to synestheic equivalences, which in turn become metaphoric identities, which then merge into abstractions of language.
perception -> synesthesia-> metaphor->language
Metaphor is therefore the reverse of what people usually assume. it depends not on some artful ability for abstract language but on our physical interaction with a concrete, sensuous world, as Berkeley linguist George Lakoff first demonstrated. Closely following his examples, let us see how our many orientational metaphors grow out of the physical experience with up and down polarities