In people with Tourette Syndrome, the thinking brain, or cerebral cortex, is short on dopamine and serotonin, chemicals that permit the brain to regulate feeling, emotion, and body functions. At the same time, a Touretter's brain often harbors unusually high levels of dopamine in the primitive structures that govern instinct and emotion. This biochemistry conspires to switch off cortical control and let wilder and more impulsive sectors of the brain take charge over behavior and emotion. With a cerebral cortex in low gear, a person with Tourette Syndrome takes in everything at once, unfiltered. Basically, stress depletes already low levels of dopamine and serotonin in the cerebral cortex.
History is full of highly creative Touretters.
Dr. Samuel Johnson, who wrote the first English language dictionary in 1755, may have been obsessive-compulsive or Tourettic. His correspondences are rife with scatological references and obscenities. This manifestation, called coprographia, is similar to coprolalia but involves the writing of obscenities. This strange behavior is seen in about a third of those with Tourette. Mozart is described by those who knew him as being constantly in motion, fidgety, with a strange habit of repeatedly touching others.