Distinct personality types make humanity very special, not only in their interactions with each other, but within themselves.
Psychiatric diagnoses of eminent people have been derived not from clinical sources but from general and popular biographies revealing apparent clay feet of creative heroes, unproven gossip and hearsay, and a field called pathography, in which both literary and psychological analysts describe correlations between artists' psychological constitutions and pathological elements they see in subject matter or characters.
Other studies have purportedly found psychopathology in people attending art or writing classes or achieving positive scores on various creativity measures.
The confused beliefs and purported findings have primarily arisen because both creativity and mental illness involve deviations, sometimes fairly extreme ones, from normative modes of thought.
Symptoms of mental illness differ from normal thinking and behavior, and creativity requires special or uncommon capacities. But there are sharp differences in effects; mental illness symptoms--compulsions, obsessions, delusions, panic attacks, depression, and personality disorders-deviate in stereotyped and frequently banal ways, whereas creativity involves novel and rich results.
The Greek philosopher Plato noted that creative types often seemed to possess "divine madness" -- a stereotype later applied to Vincent Van Gogh, Salvador Dali and Edvard Munch. However, good studies on the subject have been lacking.
Now James MacCabe at Kings College London and his colleagues have pored over the health and education records of the entire population of Sweden, focusing on the mental health of people who had done subjects like art, music or drama at university.
They found that those who had studied an artistic subject were 90 percent more likely to be hospitalised for schizophrenia, compared with the general population. Such people were also 62 percent more likely to be admitted for bipolar disorder, and 39 percent more likely to be admitted for depression.
These hospitalisations usually occurred after university, most commonly in people's mid-30s. Those with law degrees did not have the same elevated risks, suggesting psychiatric conditions are not simply linked to university education, says MacCabe.
The findings are consistent with a 2015 study of 86,000 people in Iceland, which found that artists, musicians and other creative professionals were slightly more likely to have genetic variants linked to schizophrenia and bipolar disorder.
It may be that the same genetic variants that unleash creativity can also trigger mental conditions, says MacCabe. "Creativity often involves linking ideas or concepts in ways that other people wouldn't think of," he says. "But that's similar to how delusions work -- for example, seeing a connection between the colour of someone's clothes and being part of an MI5 conspiracy."
Slightly More Common
People who feel things deeply may have more internal creative inspiration but greater emotional instability, says MacCabe. "Someone who is moved to tears by looking at a painting may have greater artistic sensitivity but also be more vulnerable to depression," he says.
But the study has some limitations, including the way it used arts degrees as a proxy for creativity. "It's not ideal because many highly creative people are not studying art," says Shelley Carson at Harvard University.
Artists shouldn't feel too worried because the risks are small, says Jeremy Hall at Cardiff University. In the Sweden study, schizophrenia still only affected 1 in 115 artistic people.
"My advice to artists would be the same as to anyone else worried about developing psychosis," says Hall. "Don't smoke cannabis and try to lead a generally healthy life."