To form a sound into a physical shape? To taste musical intervals? To see music as a colored haze? These descriptions are not the result of a vivid imagination, but the way people like Elisabeth Sulser perceive the world of music: As an expression of colors, shapes or flavors.
This rare neurological phenomena of a so called double perception is also known as synesthesia. Merely one percent of the population has the ability to combine different sensual perceptions like sounds or colors simultaneously as described above. Certain brain structures of the people concerned are linked more particular and intense then usual. Due to this fact these specific perceptions occur involuntary and cannot be suppressed.
It was at the age of sixteen that Elisabeth Sulser became aware of her synesthetic perceptions. Ever since she participated as a test person in several studies, among others in one of the Institute of Neuropsychology at the University of Zurich. Her specific version of synesthesia has been pointed out frequently in the international media, for her being the only person worldwide so far to be declared a synesthete with a interval-taste combination.
The most common occurrences are visual synesthesias. It means that visual perceptions are triggered by acoustical impressions like sounds or words. It can also signify that emotions can be triggered by visual perceptions or acoustical impressions. Over sixty versions of synesthesias are known to date, although not all of them need to be triggered by a sensory stimulus. For example many synesthetes perceive numbers as colors. But some of them may already experience a color only by visualizing a number.

Bohemian Rhapsody, Queen