One of the developing themes in recent research is the linking of creativity to biology. That same mechanism can also offer insight into mental illness, which this 2003 Science Daily article describes:
The study in the September  issue of the Journal of Personality and Social Psychology says the brains of creative people appear to be more open to incoming stimuli from thesurrounding environment. Other people's brains might shut out this same information through a process called "latent inhibition" - defined as an animal's unconscious capacity to ignore stimuli that experience has shown are irrelevant to its needs. Through psychological testing, the researchers showed that creative individuals are much more likely to have low levels of latent inhibition.
"This means that creative individuals remain in contact with the extra information constantly streaming in from the environment," says co-author and U of T psychology professor Jordan Peterson. "The normal person classifies an object, and then forgets about it, even though that object is much more complex and interesting than he or she thinks. The creative person, by contrast, is always open to new possibilities."
But not just any possibility. Some interpretive framework must be involved:
The authors hypothesize that latent inhibition may be positive when combined with high intelligence and good working memory - the capacity to think about many things at once - but negative otherwise. Peterson states: "If you are open to new information, new ideas, you better be able to intelligently and carefully edit and choose. If you have 50 ideas, only two or three are likely to be good. You have to be able to discriminate or you'll get swamped" (emphasis supplied).
"Scientists have wondered for a long time why madness and creativity seem linked," says Carson. "It appears likely that low levels of latent inhibition and exceptional flexibility in thought might predispose to mental illness under some conditions and to creative accomplishment under others."
Little latency is related to creativity, no latency to schizophrenia.
This reminds me very much of some of the current research into the nature of religiosity. Some researchers believe that "dualism" - a hardwired attraction to "things with minds" - explains a belief in God among adults. And as with creativity, at this end of biological continuum, some say, are too many loose associations.
Well I can think of one.