Do normal people also experience synesthesia?
A form of synesthesia exists in all our brains. For instance, we speak of certain smells of particular liquids–like nail polish–as being sweet, even though we have never tasted them. This might involve the close neural links and cross activations–that is, when one area of the brain affects another–between the areas involved in smell and taste. This would make sense functionally–e.g., fruits are sweet and also smell sweet like acetone. But it also makes sense structurally, because the brain pathways for smell and taste are closely intermingled and they both project signals to the same parts of the frontal cortex during sensory processing. Here’s another example. Consider how, even as infants, we scrunch up our noses and raise our hands when we encounter disgusting smells and tastes. We also use these gestures, as well as the word “disgusting,” to describe a person who is morally questionable. Why do we use the same word as for taste? Why not say he is “painful,” for instance? The r
