There are people who perceive our world differently. They see numbers and letters in color, can taste words, feel sounds, or see feelings.

A one is green, and A is purple, a red apple is C major, and a Riesling wine tastes blue. It sounds absurd but these perceptual phenomena are not pathological. They are a special ability called synaesthesia. Synaesthetes are "normal" people with an additional talent for the processing of sensory stimuli as well as perception and thinking. Neuroscientists have discovered that synaesthetes have an increased functional coupling between brain regions that make simultaneous sensory perceptions possible. With the research of synaesthesia, neuroscientists hope to learn more about the organization and function of the brain and thereby gain new insights into the functioning of human consciousness.