- Note: Synaesthesia was the name of a series of events that took place in Rochester, NY in 2003 (see Synaesthesia (events)). There is also an industrial music band called Synæsthesia.
Synaesthesia (also spelled synesthesia); from the Greek (syn-) “union”, and (aesthesis) “sensation”; is the neurological mixing of the senses. A synaesthete may, for example, hear colors, see sounds, and taste tactile sensations. Although considered a symptom of autism, it is by no means exclusive to those with autism. Synaesthesia is a common effect of some hallucinogenic drugs such as LSD or mescaline.
Synaesthetes often experience correspondences between the shades of color, tones of sounds, and intensities of tastes that provoke alternate sensations. For instance, a synaesthete may see a more intense red as the pitch of a sound gets higher, or a smoother surface might make one taste a sweeter taste. These experiences are not metaphorical or merely associations; rather, they are involuntary and are consistent throughout life, although some young synaesthetes seem to lose their ability by or during adulthood. Depressant drugs tend to increase the depth of the perception.
Synaesthesia can even occur when one of the senses no longer functions properly, e.g., a person who can see colours when words are spoken can still see the colours if he becomes blind in later life. This phenomenon is known as "martian colors." The term originated from a case of a synaesthete who was born partially color blind, but saw certain 'alien' colors in his synaesthetic perceptions that he never saw (was incapable of seeing) in the 'real world.'
The most common forms of synaesthesia involve colour, being assigned to letters, numbers, days of the week or (especially for musicians) musical keys.
Alternate spellings exist (synaesthesis, synesthesia), and many of those who experience the phenomenon identify as "synaesthetes".
Synaesthesia in art
- Annihilating all that's made
- To a green thought in a green shade
- ( —"The Garden")
- Sometimes you can smell the green
- When your mind is feeling fine
- ( —Aliotta, Haynes and Jeremiah)
Synaesthesia has influenced many artists in various fields, including poets Charles-Pierre Baudelaire and Arthur Rimbaud (specifically his poem Voyelles), and an ersatz synaesthesia has sometimes been overused since as a shortcut to "modernity."
Composer Alexander Scriabin, in his orchestral work, Prometheus: Poem of Fire (1910), included a part for a "clavier à lumières". This instrument was played like the piano, but produced colored light instead of sound. Scriabin did not experience the physiological condition of synaesthesia. The color system he described and which he used in pieces such as Prometheus, unlike most systems and synaesthetic experience, lines up with the circle of fifths, indicating that it was a thought-out system; it was also influenced by his theosophic readings and based on Sir Isaac Newton's Optics. Many other artists have used fabricated synesthetic systems, such as the Italian futurist Filippo Tommaso Marinetti and the Russian abstract-painting pioneer Wassily Kandinsky.
Amy Beach was a synesthete, seeing different colors for different keys, as well as possessing absolute pitch. Nikolai Rimsky-Korsakov was reputed to be a synesthete. Olivier Messiaen was a true synesthete; he discussed his condition to a great extent in his writings, going so far as to describe in detail the exact colorations evoked by particular chords. Contemporary postminimal composer Michael Torke is a synesthete who perceives colors for various time units. French drummer Manu Katché and world-renowned oboist Jennifer Paull are both synesthetes, Katche seeing various images with music, and Paull seeing an expanded unexplainable spectrum to various sounds, the sensation of the oboe compelling her to take it up.
Franz Liszt, when conducting, confused the musicians by describing timbres or sonorities in chromatic terms. Ludwig van Beethoven considered B minor to be "the black key," and Franz Schubert viewed E minor as like "a maiden robed in white and with a rose-red bow on her breast." In such cases of long-dead people, it is difficult to tell whether they were describing their synesthesia or using figures of speech such as those from Marvell and Fitzgerald above.
Jimi Hendrix, who knew little music theory, would attempt to describe chords and harmony in terms of colour. For example, the chord E7#9 (often referred to by guitar players as the 'Hendrix chord') gave him a strong sense of the colour purple. The chord is played under the words 'purple haze' in each verse of the song of that name.
As digital entertainment becomes more developed, the possibility of synaesthesia through technology has begun to be considered. Several video games already use the term in their advertising, most notably the 2001 Dreamcast/PlayStation 2 game REZ (which does have some elements of synaesthesia in its gameplay, notably the interaction of controller vibration, music, player interaction and graphics).
The ability to read could be also be considered a form of synaesthesia - the linking of shapes to sounds.
Synaesthesia is a real phenomenon: indeed, some people see colors when they hear or read letters and numbers (the most common form). Others taste and feel sounds, colors, and so forth. There are many people with Synaesthesia. It is estimated that 10% of people are Synaesthetes. But only those awarely perceiving their Synaesthesia can recognize the inner colors.  Synaesthetes have been studied by neurologist V. S. Ramachandran at the University of California, San Diego, who remarked that "processes similar to synaesthesia might also underlie our general capacity for metaphor and be critical to creativity." Ramachandran has said it is "not an accident" that the phenomenon is noted eight times more frequently in writers and artists than in the typical population, and is more common in creative people. Synaesthesia often runs in families. About one-third of synaesthetes report that another family member experiences similar phenomena.
Another leading psychologist, currently a fellow at Trinity College, Cambridge, Prof. Simon Baron-Cohen, is also undergoing ground-breaking research into the topic.
In synaesthesia's most common form (Grapheme-color synaenesthesia), individual letters of the alphabet, as well as numbers, are "shaded" or "tinged" with a color. The alphabet color pattern is different for every individual. Many synaesthetes report that they were unaware their abilities were special or unusual until they realized other people didn't have them. Writer (and synaesthete) Patricia Lynne Duffy remembers the experience: "'one day,' I said to my father, 'I realized that to make an 'R' all I had to do was first write a 'P' and then draw a line down from its loop. And I was so surprised that I could turn a yellow letter into an orange letter just by adding a line.'"
From another grapheme-color synesthete: "I often associate letters and numbers with colors. Every digit and every letter has a color associated with it in my head. Sometimes, when letters are written boldly on a piece of paper, they will briefly appear to be that color if I'm not focusing on it. Some examples: "S" is red, "H" is orange, "C" is yellow, "J" is yellow-green, "G" is green, "E" is blue, "X" is purple, "I" is pale yellow, "2" is tan, "1" is white. If I write SHCJGEX it registers as a rainbow when I read over it, as does ABCPDEF." (From a slashdot discussion)
Another account: "I have synesthesia, and as a child I thought it was normal until I realized other people didn't see numbers and letters as colours. I believe synesthesia can link any kind of sensory input to abstract forms like letters and numbers, but in my case (and in most), it's simple colours. This makes it easy for me to remember trivial information like phone numbers, account numbers, historical dates, and pi (3.141592653589 is how far I remember without looking it up). Every string of numbers and letters forms a composite colour based on those of its individual characters. I've studied Japanese for a few years and now find that Japanese syllable characters also have colours for me now. I imagine that with extreme synesthesia, a person might understand abstract notions like numbers and math in a completely different way. I remember once showing my sister two Smarties (they're like M&Ms) and telling her they were '3' and '6' instead of yellow and green. It took me a moment to realize why she didn't understand." (From a slashdot discussion)
Research indicates that, while few grapheme-color synaesthetes perceive the color associations of the alphabet in exactly the same way, the distribution of patterns and colors shows striking trends and similarities. Although grapheme-color synaesthetes have the highest rate of incidence, there are (according to one researcher) 40 distinct types of synaesthesia, including varieties affecting the sense of taste, smell, music, and touch.
- Cognitive neuroscience
- Mind's eye
- Schmidt Sting Pain Index (A good example.)
- The Color of Sound Cool Flash experiment where you can assign colors to sounds and see how other people voted.
- Synaesthesia and MigraineSynaesthesia may occur as a visual migraine aura.
- People who feel color gets scientific acceptance
- Synesthesia research project in Waterloo, Ontario (volunteer synaesthetes needed)
-  Colortronic is an electronic music project from Brazil which blends color and music.
-  A highly synaesthetic person's experience including letters having colour and texture, and digits having colour and personality.
-  A girl's Geocities page about her gustatory, or word-tasting, synesthesia.
-  Crétien van Campen, 'Artistic and psychological experiments with synesthesia' gives the historical background.
-  Richard Cytowic, 'Synesthesia: phenomenology and neuropsychology' emphasizes the involuntary nature of the cross-modal perceptions and 'distinguishes it from metaphor, literary tropes, sound symbolism, and deliberate artistic contrivances that sometimes employ the term "synaesthesia" to describe their multisensory joinings.'
-  Crétien van Campen, 'Synesthesia and artistic experimentation' comments on Cytowic, adducing the examples of Scriabin's and Kandinsky's experiments as relevant for the study of synesthesia.
-  Synaesthesia and the Arts - Dr. Hugo Heyrman 'Museums of the Mind'. Research and theory on the future of the senses. Homepage of the Belgian Synesthesia Association.
- Synaesthesia and Education: a research project at the University of Cambridge investigating the effects of grapheme-colour synaesthesia on numerical processing in children.
- Scientific American article Hearing Colors, Tasting Shapes (PDF version) by Vilayanur S. Ramachandran and Edward M. Hubbard, May 2003.
- A Brief History of Synaesthesia and Music
- A Mango-Shaped Space, a novel about a 13-year-old with synesthesia by Wendy Mass
- Synaesthesia - union of the senses (from Kuro5hin)
- Blue Cats and Chartreuse Kittens by Patricia Lynne Duffy
- American Synesthesia Association
- CNN article on tasting musical tones
- Why some see colours in numbers at BBC News, 24 March, 2005
- Artificial synesthesia (for the blind)
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