Ideas Rain In

In 1675 Isaac Newton suffered a mental breakdown—some modern psychiatrists diagnose him as a manic-depressive—and he was still recovering in 1679. But long before that, Newton had already invented calculus and formulated his law of gravitational attraction. Throughout history, genius and madness have often dwelled together: think of Vincent Van Gogh, William James, M.D. 1869, and, more recently, mathematician John Forbes Nash (portrayed in the book and film A Beautiful Mind). Delusional psychosis and inspired creativity, ostensible antipodes of human experience, ironically also seem to be next-door neighbors. Over the centuries, thinkers have wrestled with this enigma, usually on a purely speculative basis. Now, a new empirical study suggests a specific style of cognition shared by those who hear the Muse and those who merely hear voices. The research also suggests variables that distinguish the two groups.

In a paper published in the Journal of Personality and Social Psychology, lecturer on psychology Shelley Carson, Ph.D. '01, Harvard graduate student Daniel Higgins, and Jordan Peterson of the University of Toronto (formerly assistant professor of psychology at Harvard) focus on "latent inhibition," a cognitive mechanism discovered as a result of experiments with animals in the late 1950s. Latent inhibition is the capacity of an animal to unconsciously screen out stimuli perceived as irrelevant to its needs.

Psychologists have generally linked a low level of latent inhibition to psychotic conditions like schizophrenia; the lack of filtering can even flood the mind with random inputs. But the eminent psychologist Hans Eysenck also speculated that low latent inhibition might be one of the cognitive deficits that creative and psychotic people share. Although too much material entering the "cognitive working area" might disorient psychotics, Carson wondered whether "highly creative people could use those many bits and pieces in the cognitive workspace and combine them in novel, original ways."

The researchers studied two groups of Harvard undergraduates, of 86 and 96 people, respectively. They rated the subjects' creativity using three types of psychological tests, including one that inventoried actual creative accomplishments. One instrument, a "divergent thinking" task, asked subjects to write down, in three minutes, a list of alternate uses for a common object like a brick, or to list edible things that are white. For the latter challenge, creative thinkers go beyond potatoes and popcorn to "responses like paper, paste, Eucharist wafers, and underwear," Carson notes. The researchers also gave subjects IQ tests and measured their latent inhibition levels with a task that involved abstract audio and visual signals. The data showed that high lifetime creative achievers had significantly less latent inhibition than low creative achievers.

The psychologists also identified a third group: 25 Harvard undergraduates who were "eminent creative achievers" in a single domain. Inclusion in this group required accomplishments like having a novel, book of poetry, or musical composition published (or recorded) and sold, having a prototype invention patented and built, or having a private showing of original artwork at a recognized gallery. Such young creators proved seven times more likely to have low latent inhibition scores than high ones.

Intelligence (the mean IQs of the three subject pools fell between 120 and 130), when married to low latent inhibition, may potentiate original thought. These two factors combined to explain one-fifth to one-quarter of the variance in creativity among the three groups of students. "Intelligence allows you to manipulate the additional stimuli in novel ways without being overwhelmed by them," Carson explains. "IQ may act as a protective factor. That does not mean it will prevent psychosis.

"If a cause of psychosis is a failure of filtering, those who suffer from it may have difficulty determining if stimuli are internally or externally generated," Carson says, noting that the average age of onset for schizophrenia is 16 for males and 20 for females, a time when adolescents are defining their boundaries. "A memory or a mental image may appear to be coming from the outside; consequently, psychotics attach emotional significance to random stimuli. They develop an associational network that is not comprehensible to anyone else—their network is both broader and shallower than that of the general population.

"This is also true for creative persons," Carson continues. "Imagination comes from image, an internally generated image. What you do with that image has a lot to do with whatever else is in your mind. Preparation is a part of creativity. If you're a real artist, you know your field; when ideas start coming, you know when there is an aesthetic fit. Creators can communicate their associations with other people in a form that is original, useful, or that resonates with a certain portion of the population."

However, while intelligence and preparation may be necessary, they may not be enough to produce creativity. "Maybe it's working memory capacity that is the protective aspect," Carson says. "How many things can you hold in your mind and process and manipulate?" In a preliminary, unpublished study, she says, "The combination of low latent inhibition and high working memory also predicted creative achievement."

~Craig Lambert


Shelley Carson e-mail address:

Read more articles by Craig Lambert

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