What is the color of A?
What's the colour of Tuesday? What's the week's form? Can music have a taste, can taste have a melody? Such questions might appear strange on first sight, but for many people they are completely normal.
What is synaesthesia?
Synaesthesia is a special crosslinking in the brain, which causes multiple senses to be activated simultaneously. Synaesthesia is quite common.
People living with "united senses" are called synaesthetes. Many synaesthetes are able to feel letters or to taste words. Others can see sound in bright colours ("coloured hearing"), which is one of the most frequent kinds of synaesthesia.
There are clearly more synaesthete women than men (estimated 3:1 to 7:1). Because of the accumulation in families, heritability is assumed.
Not all synaesthetes know about their gift. You have to observe sensible to experience synaesthesia.
The word synaesthesia is derived from the ancient greek words syn (= together) and aisthesis (= to sense), the dictionary describes it as the additional activation of a sense organ on stimulation of another one, in the broadest sense it is also the trigger of an impression caused by a different impression.
Synaesthesia means additional neural channels between the senses. Studies and experiences show that certain phenomena appear often for synaesthetes. Those may be high intelligence and creativity. as well as increased sensitivity and concentration problems.