“I think I’ve only spent about ten percent of my energies on writing,” Pulitzer Prize-winning writer Katherine Anne Porter confessed in a 1963 interview. “The other ninety percent went to keeping my head above water.” While art may be a form of therapy for the rest of us, Porter’s is a sentiment far from uncommon among the creatively gifted who make that art. Why?

When Nancy Andreasen took a standard IQ test in kindergarten, she was declared a “genius.” But she was born in the late 1930s, an era when her own mother admonished that no one would marry a woman with a Ph.D. Still, she became a psychiatrist and a neuroscientist, and made understanding the brain’s creative capacity her life’s work. Having grown up steeped in ambivalence about her “diagnosis” of extraordinary intellectual and creative ability, Andreasen wondered about the social forces at work in the nature-nurture osmosis of genius, about how many people of natural genius were born throughout history whose genius was never manifested, suppressed by lack of nurture. “Half of the human beings in history are women,” she noted, “but we have had so few women recognized for their genius. How many were held back by societal influences, similar to the ones I encountered and dared to ignore?” (One need only look at the case of Benjamin Franklin and his sister to see Andreasen’s point.)

Andreasen didn’t heed her mother’s warning and went on to become a pioneer of the neuroimaging revolution, setting out to understand how “genius” came to be and whether its manifestation could be actively nurtured — how we, as individuals and as a society, could put an end to wasting human gifts. She did get a Ph.D., too, but in Renaissance English literature rather than biochemistry — a multidisciplinary angle that lends her approach a unique lens at that fertile intersection of science and the humanities.

In The Creating Brain: The Neuroscience of Genius (public library), Andreasen — whom Vonnegut once called “our leading authority on creativity” — crystallizes more than three decades of her work at the intersection of neuroscience, psychology, and cultural history.

One of the most interesting chapters in the book deals with the correlation between creativity and mental illness, bringing scientific rigor to such classic anecdotal examples as those evidenced in Van Gogh’s letters or Sylvia Plath’s journals or Leo Tolstoy’s diary of depression or Virginia Woolf’s suicide note. Having long opposed the toxic “tortured genius” myth of creativity, I was instantly intrigued by Andreasen’s inquiry, the backdrop of which she paints elegantly:

Did mental illness facilitate [these creators’] unique abilities, whether it be to play a concerto or to perceive a novel mathematical relationship? Or did mental illness impair their creativity after its initial meteoric burst in their twenties? Or is the relationship more complex than a simple one of cause and effect, in either direction?

She cites the work of Havelock Ellis, one of the earliest scholars of creativity, a Victorian physician, writer and social reformer ahead of his time. In 1926, in his late sixties, he published A Study of British Genius, an effort to provide a scientific assessment of the link between genius and psychopathology by studying a sample of people found in the British Dictionary of National Biography — a compendium of about 30,000 eminent public figures, whom he sifted through a set of criteria to identify 1,030 displaying “any very transcendent degree of native ability.” Andreasen recounts his findings:

The rate of “insanity” noted by Ellis is certainly higher than is usually recorded for the general population, for which the current base rate is 1 percent for schizophrenia and 1 percent for mania. These are the two most common psychotic illnesses. The rate of melancholia — or what we currently call depression — is similar to current lifetime population rates of approximately 10 to 20 percent.

Once she became a psychiatrist, having come from a literary world “well populated with people who had vividly described symptoms of mental illness,” Andreasen decided to apply everything science had uncovered in the decades since Ellis’s work and design a rigorous study on the relationship between creativity and mental illness. Andreasen had attended the University of Iowa Medical School and had completed her residency in psychiatry there — a somewhat fortuitous circumstance that presented her with the perfect, quite convenient sample pool for her study: the Iowa Writers’ Workshop, one of the most prestigious creative-writing programs in the world, which has included such distinguished faculty as Kurt Vonnegut and Annie Dillard since its inception in 1936.

Andreasen’s study had a couple of crucial points of differentiation over Ellis’s work and other previous efforts: Rather than anecdotal accounts in biographies of her subjects, she employed structured, first-person interviews; she then applied rigorous diagnostic criteria to the responses based on The Diagnostic and Statistical Manual of Mental Disorders, the bible of modern psychiatry. Andreasen writes:

In addition to incorporating diagnostic criteria, the Iowa Writers’ Workshop Study also improved on its predecessors by including a group of educationally matched controls. The Writers’ Workshop has a limited number of permanent faculty members (typically two poets and two prose writers). The remainder of the faculty in any given year consists of visiting writers who come to Iowa, drawn by its pastoral tranquility and an opportunity to be “far from the madding crowd” for a time of introspection, incubation, and isolation. […] I began the study with a perfectly reasonable working hypothesis. I anticipated that the writers would be, in general, psychologically healthy, but that they would have an increased rate of schizophrenia in their family members. This hunch made good sense, based on the information that I had at that time. I was influenced by my knowledge about people such as James Joyce, Bertrand Russell, and Albert Einstein, all of whom had family members with schizophrenia.

But as she began administering the interviews and applying to them the diagnostic criteria, her working hypothesis quickly crumbled: To her bewilderment, the majority of the writers “described significant histories of mood disorder that met diagnostic criteria for either bipolar illness or unipolar depression.” Most had received treatment for it — some with hospitalization, some with outpatient therapy and medication. Perhaps the most startling contrast with her initial hunch was the fact that not a single writer displayed any symptoms of schizophrenia.

And this is where the monumental importance of her study shines: What Andreasen found wasn’t confirmation for the “tortured genius” myth — the idea that a great artist must have some dark, tragic pathology in order to create — but quite the opposite: these women and men had become successful writers not because of their tortuous mental health but despite it.

Andreasen reflects on the findings:

Although many writers had had periods of significant depression, mania, or hypomania, they were consistently appealing, entertaining, and interesting people. They had led interesting lives, and they enjoyed telling me about them as much as I enjoyed hearing about them. Mood disorders tend to be episodic, characterized by relatively brief periods of low or high mood lasting weeks to months, interspersed with long periods of normal mood (known as euthymia to us psychiatrists). All the writers were euthymic at the time that I interviewed them, and so they could look back on their periods of depression or mania with considerable detachment. They were also able to describe how abnormalities in mood state affected their creativity. Consistently, they indicated that they were unable to be creative when either depressed or manic.

More than that, her study confirmed two pervasive yet conflicting ideas about the relationship between creativity and mental illness:

One point of view … is that gifted people are in fact supernormal or superior in many ways. My writers certainly were. They were charming, fun, articulate, and disciplined. They typically followed very similar schedules, getting up in the morning and allocating a large chunk of time to writing during the earlier part of the day. They would rarely let a day go by without writing. In general, they had a close relationship with friends and family. They manifested the Freudian definition of health: lieben und arbeiten, “to love and to work.” On the other hand, they also manifested the alternative common point of view about the nature of genius: that it is “to madness near allied.” Many definitely had experienced periods of significant mood disorder. Importantly, though handicapping creativity when they occurred, these periods of mood disorder were not permanent or long-lived. In some instances, they may even have provided powerful material upon which the writer could later draw, as a Wordsworthian “emotion recollected in tranquility.”

Andreasen’s seminal study inspired a series of related research, most notably a project by British psychologist Kay Jamison, who examined 47 prominent poets, playwrights, novelists, biographers, and artists to find that a significant portion of them had mood disorders. Harvard psychiatrist Joseph Schildkraut found even starker evidence of the same tendency in a study of 15 mid-century abstract expressionists — about half had “some form of psychopathology, which was predominantly mood disorder.”

Andreasen returns to the question of why mood disorders are so common among writers, but schizophrenia — which she initially expected to find — is not:

The evidence supporting an association between artistic creativity and mood disorder is quite solid, as is the absence of an association with schizophrenia. The nature of artistic creativity, particularly literary creativity, is probably not compatible with the presence of an illness like schizophrenia, which causes many of its victims to be socially withdrawn and cognitively disorganized. An activity such as writing a novel or a play requires sustained attention for long periods of time and an ability to hold a complex group of characters and a plot line “in the brain” for as long as one or two years while the novel or play is being designed, written, and rewritten. This type of sustained concentration is extremely difficult for people suffering from schizophrenia. Creativity in other fields may, however, be compatible with an illness like schizophrenia, particularly those fields in which the creative moment is achieved by flashes of insight about complex relationships or by exploring hunches and intuitions that ordinary folk might find strange or even bizarre.

(The famed Russian composer Tchaikovsky, who some scholars have speculated had symptoms of schizophrenia, articulated those “flashes of insight” spectacularly in his 1876 letter on the “immeasurable bliss” of creativity.)

Andreasen considers the unique psychoemotional constitution of the highly creative person, both its blessing and its curse:

Many personality characteristics of creative people … make them more vulnerable, including openness to new experiences, a tolerance for ambiguity, and an approach to life and the world that is relatively free of preconceptions. This flexibility permits them to perceive things in a fresh and novel way, which is an important basis for creativity. But it also means that their inner world is complex, ambiguous, and filled with shades of gray rather than black and white. It is a world filled with many questions and few easy answers. While less creative people can quickly respond to situations based on what they have been told by people in authority — parents, teachers, pastors, rabbis, or priests — the creative person lives in a more fluid and nebulous world. He or she may have to confront criticism or rejection for being too questioning, or too unconventional. Such traits can lead to feelings of depression or social alienation. A highly original person may seem odd or strange to others. Too much openness means living on the edge. Sometimes the person may drop over the edge… into depression, mania, or perhaps schizophrenia.

She considers the cognitive machinery common to both creative thinking and mental turmoil:

Creative ideas probably occur as part of a potentially dangerous mental process, when associations in the brain are flying freely during unconscious mental states — how thoughts must become momentarily disorganized prior to organizing. Such a process is very similar to that which occurs during psychotic states of mania, depression, or schizophrenia. In fact, the great Swiss psychiatrist Eugen Bleuler, who gave schizophrenia its name, described a “loosening of associations” as its most characteristic feature: “Of the thousands of associative threads that guide our thinking, this disease seems to interrupt, quite haphazardly, sometimes single threads, sometimes a whole group, and sometimes whole segments of them.”

Of course, we now know that this crossing of the wires that combines seemingly unrelated concepts is also the essence of creativity — or what Einstein once described as the “combinatory play” at the heart of ideation — and why dot-connecting is vital for great art. Andreasen writes:

When the associations flying through the brain self-organize to form a new idea, the result is creativity. But if they either fail to self-organize, or if they self-organize to create an erroneous idea, the result is psychosis. Sometimes both occur in the same person, and the result is a creative person who is also psychotic. As [schizophrenic mathematician John] Nash [who inspired the film A Beautiful Mind] once said: “the ideas I have about supernatural beings came to me the same way that my mathematical ideas did, so I took them seriously.”

This failure to self-organize stems from what cognitive scientists call input dysfunction — a glitch in the filtering system we use to tune out the vast majority of what is going on around us. Andreasen explains:

All human beings (and their brains) have to cope with the fact that their five senses gather more information than even the magnificent human brain is able to process. To put this another way: we need to be able to ignore a lot of what is happening around us — the smell of pizza baking, the sound of the cat meowing, or the sight of birds flying outside the window — if we are going to focus our attention and concentrate on what we are doing (in your case, for example, reading this book). Our ability to filter out unnecessary stimuli and focus our attention is mediated by brain mechanisms in regions known as the thalamus and the reticular activating system.

Creative people, Andreasen notes, can be more easily overwhelmed by stimuli and become distracted. Some of the writers in her study, upon realizing they had a tendency to be too sociable, employed various strategies for keeping themselves isolated from human contact for sizable stretches of time in order to create. (Victor Hugo famously locked away all his clothes to avoid the temptation of going out while completing The Hunchback of Notre Dame in 1830, which he wrote at his desk wearing nothing but a large gray shawl.) And yet for all its capacity to overwhelm, the creative mind remains above all a spectacular blessing:

Our ability to use our brains to get “outside” our relatively limited personal perspectives and circumstances, and to see something other than the “objective” world, is a powerful gift. Many people fail to realize that they even have this gift, and most who do rarely use it.

The Creating Brain is a fascinating read in its entirety. Complement it with a brief cultural history of “genius,” Bob Dylan on creativity and the unconscious mind, the psychology of how mind-wandering and “positive constructive daydreaming” boost creativity, and Carole King on overcoming creative block.