Mind Moves: Can you imagine seeing colours when you hear music: hearing the colours of Fauré's Pavane or Tchaikovsky's Chanson Triste? What coloured cascades might Mozart's music bring? What gathering lights or whites Debussy's Clair de lune? And would Vivaldi evoke traditional seasonal 'tones' or would each note provide a different coloured shade of sound?
These are the kind of questions cognitive neuroscientists and neuropsychologists studying the intriguing condition known as synaesthesia might ask as part of their constant quest to understand how the brain determines mind.
The word synaesthesia (also spelt synesthesia) derives from the Greek word for union of the senses with syn meaning together/shared and aesthesis meaning sensation/perception. It relates to the condition where stimulating one sense triggers another so that you may conceivably taste shape, smell colour and see sound. This is involuntary sensory cross-activation and those people, known as synaesthetes, who enjoy such hybrid vibrations may not know that others do not share their rich intersensorial world.
Researchers into synaesthesia emphasise the involuntary nature of the experience compared to the deliberate use of metaphor, contrived creative interchange of co-sensory words in literature and poetry, literary troops or sought sensory fusion in audio-visual, spatial or multisensory music. Nor is it the same as pseudosynaesthesia, which can occur with drug use, such as LSD, providing the confusion of the senses.
The literature on synaesthesia is vast, highlighting that it runs in families with more women than men (ratios from 3:1 to 8:1), there is a tendency to be left-handed, to have an excellent memory, and there is debate about whether it is present in infancy and subsequently lost and whether more artistic, intuitive, psychic and creative people are synaesthetes and in what circumstances it may help or hinder a person.
References to synaesthesia extend back to Newton's observations that there was a parallel between colours of the spectrum and the notes on a musical scale from which he designed a colour music wheel. However, it is only in recent times that significant interdisciplinary attention has been paid to the condition of synaesthesia as the technology of brain functional imaging allows us to observe the brain in action, record subjective experience and to revisit ideas of the brain as self-contained subsystems.
As US researcher Richard Cytowic writes, "although medicine has known about synaesthesia for three centuries, it keeps forgetting that it knows".
But this is a condition that behoves us to remember because of the insight it may provide into the working of the brain: into memory, modes of learning and detailed recall. Many synaesthetes report amazing memory for poems, prose and dialogue and have superior photogenic spatial recall with a mental map of the exact location of a book on a shelf, a poem in a book or an object in the garden shed.
Understanding synaesthesia may provide more information on sensation and perception, the connections between reason and emotion, and conscious and unconscious processes.
There is significant controversy as to whether understanding synaesthesia may provide more understanding of conditions like dyslexia (although many synaesthetes report seeing letters or words in colour form), dyscalculia, or problems in mathematical reasoning, allochiria, which is right-left confusion and poor sense of direction, experiences of deja-vu and psychic phenomenon.
Perhaps there are more ordinary experiences. Our language is replete with images and words that show our accessibility to this fusion of feelings engendered by the senses. We speak of 'loud colours' and 'heavy tones', 'sharp sounds', 'vivid smells' and the 'bitter word'. And we speak of 'cheerful yellow' and we often 'sing the blues' and we see what we mean when we say these things. This is why some thinkers, such as the Russian Galeyev, believe we misunderstand synaesthesia and each of us carries the potential to capture, sensitively and with sensuality, the world of beauty, the world of art and artistry, the aesthetic world, which, he reminds us, is another Ancient Greek word from which synaesthesia may derive.
Certainly, the wealth of artists and poets identified as synaesthetes who seem to have translated their co-sensory experiences of imaginary endeavours for us, are many and varied. So what can we say about the musicality of colour or the chromatism of music? Well, think of the artist David Hockney. Just look at his painting A Bigger Splash for a vision of that sound, or Jackson Pollock's dripping smearing paint, or artist Kupka's Discs of Newton or his Piano Keyboard Lake based on a colour music code of scientist Helmholtz.
Think of the works of Kandinsky, the music of Liszt translating the writings of Hugo, Byron and Goethe. And why is our own James Joyce not on the list? On page 565 of Ulysses, he shows possible membership of the world of synaesthetes with the words, "he could hear, of course, all kinds of words changing colour, like those crabs about Ringsend in the morning burrowing quickly into all colours of different sorts".
Synaesthesia captures our imagination, perhaps, because it is the place where science and art collide, where philosophy and neurology, genetics, psychology and theology may reside and coincide: for if we look at the brain, in what part does poetry lie, where in the occipital lobe is the artist?
We know that we are more, much more, than sensory and neuronal paths however complex these may be and that these physiological pathways are passages to imagination, corridors of creativity to possibilities beyond.
• Marie Murray is Director of Psychology at St Vincent's Psychiatric Hospital Fairview.
• Research into synaesthesia is currently being conducted in the Department of Psychology, Trinity College, Dublin. More details at www.tcd.ie/psychology/synres Email: synres@tcd.ie - Tel: 086-0767753.