Other Types of Synesthesia

At its most basic level, synesthesia is a mixing of the senses. The term derives from the Greek words "syn" (together) and "aesthesia" (sensation). There are four main types of synesthesia, but even these can be difficult to separate or may be found together in one person.

  • Color-grapheme synesthesia - colors are associated with numbers, words or letters
  • Sound-color synesthesia - sounds are associated with colors
  • Word-taste synesthesia - words are associated with tastes
  • Taste-touch synesthesia - tastes are associated with physical sensations

In some cases, people also associate letters or words with colors and qualities. For example, the letter 'E' could be red, jagged and powerful. Some synesthetes also cite letters, months or days of the week as having three-dimensional qualities.

People with color-grapheme synesthesia associate colors with letters.
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Someone with color-grapheme synesthesia may associate a color with each letter of the alphabet.

Despite various hypotheses, the causes of synesthesia are still unknown, though it's believed to have a hereditary association. Researchers believe that it's found in one out of every 100 or 200 people and is more common in women and left-handed people.

Men with morning sickness?
Not quite sympathy pains or mirror-touch synesthesia, a unique condition known as Couvade syndrome has afflicted some men with pregnant partners. These men have involuntarily experienced many of the symptoms of pregnancy -- food cravings, mood swings, cramps, enlarged stomachs, back ache, even morning sickness. Some symptoms persist until delivery -- one man even told the BBC that he thought his labor pains were more severe than his wife's! The symptoms usually go away after the baby is born, but men seem to have no control over them.

Like the mirror-touch synesthete who thought everyone was like her or people who go years without knowing that they are color-blind, some synesthetes may not even think they're different at all. That may especially be true for developmental synesthetes, those who have had synesthesia all their lives. Others can develop what's known as acquired synesthesia, which can be caused by drug use or brain injuries.

For those who have it, synesthesia can be useful. Synesthetic associations can boost memory abilities, and numerous artists, musicians, writers and other creative types have cited their synesthesia as an important component in their work. While some famous suspected synesthetes haven't been confirmed, here are some prominent people who have or had synesthesia:

  • Duke Ellington (jazz musician)
  • Richard Feynman (physicist, Nobel Prize winner)
  • David Hockney (painter)
  • Wassily Kandinsky (painter)
  • Franz Liszt (composer, conductor, pianist)
  • Vladimir Nabokov (writer, lepidopterist)
  • Nikolai Rimsky-Korsakov (composer)
  • Pharrell Williams (musician, producer)

For more information about synesthesia, the brain and other related topics, please check out the links on the next page.