Lots of people have dark holes inside them, but some have sewers - places so deep and putrid it's best to keep them covered. Art is often the pipeline through which the putrid sewage leaks. People who become artists often share strikingly similar traits with those who become serial killers: abusive parents, traumatic childhood events, and marked scarcity of the brain chemical serotonin. Scientists are now finding that people with a mild form of manic depression tend to rhyme and use sound associations, such as alliteration, far more frequently than patients without the disorder. In a 1995 Scientific American article, Kay Redfield Jamison, a professor of psychiatry at Johns Hopkins University, noted that this "familiarity with transitions" is "probably useful in artistic endeavors." In fact, one of the criteria that psychiatrists use to diagnose mania is "sharpened and unusually creative thinking." One possible cause of manic-depressive disorder is an imbalance of the chemicals serotonin and norepinephrine. Recent studies have found chemical differences in the brains of highly creative people, including increased serotonin transporters and dopamine receptors.
In 1992 Arnold M. Ludwig from the University of Kentucky published a survey of 1,005 famous twentieth-century artists, writers, and other professionals. He discovered that artists and writers experienced 2-3 times the rate of psychosis, suicide attempts, mood disorders, and substance abuse than people in science, business, and public life. Poets, in particular, were a staggering 18 times more likely to commit suicide than the general public. But then most poets are 99.9 times more likely to make no money at all from their artistic endeavors.