The Evolutionary Explanation for the Link Between Mental Illness & Creativity

Is it true that mental illness is associated with creativity -
or is that just a myth?

There is a bit of an evolutionary puzzle surrounding the persistence of mental illness, particularly debilitating conditions like schizophrenia. Many forms of mental illness are heritable and also associated with dramatically reduced ability to cope effectively with day-to-day life. If such conditions interfere so dramatically with life, wouldn't they impede reproduction too? Of so, then why do genes linked with schizophrenia persist?

The authors of the research article Schizotypy, creativity and mating success in humans provide some intriguing answers to this paradox. Their article was published in the Proceedings of the Royal Society, a well-respected journal, in 2005.

Schizotypy refers to a personality type that shares many of the same traits as schizophrenia, but not to the same extreme. The traits are:

• magical thinking, unusual experiences
  
• attention & concentration difficulties
• impulsive non-conformity (rash, reckless behavior that is eccentric)
• introverted anhedonia (social withdrawal, lack of enjoyment)
  

Several studies have found that artists and others active in the creative arts have elevated levels of some of these schizotypal traits. Specifically, the first and third.

In fact, artists and poets score as high on those two traits as schizophrenia patients do.

These are also traits that should theoretically lead to having more sexual partners, and hence, greater mating success. That final part is an important piece of evidence the authors use to explain why these traits persist in the general population. I should point out that the number of children schizotypal people have is a more valid measure of reproductive success than their number of sexual partners.

The authors of the study looked at correlations between the personality traits, creativity, and sexual activity. They used a sophisticated type of statistical analysis to guess at the causal relationships. Correlational data can never be used to determine whether one thing causes another, such whether being schizotypal causes one to produce more art. For that you need an experiment that manipulates one to see the effect on the other. However, path analysis can hint at causal relationships.

Using path analysis, the authors found that having a lot of unusual experiences ( I wish they had given some examples, but they didn't - boo) affects artistic output, which in turn affects sexual activity. What this means is that more prolific artists have more sexual partners.

This is consistent with psychologist Geoffrey Miller's theory that artistic creativity functions as courtship display - something akin to a peacock strutting its feathers.