01/23/2012 03:04 pm ET Updated Mar 24, 2012

Depression, Memory and Adaptation

Mental illness is a killer. It takes the life of a person every 15 minutes in this country. And suicide is the fourth highest cause of death among those between the ages of 18 and 65, according to the American Foundation for Suicide Prevention. Moreover, the World Health Organization indicates that, by 2020, depression will be the second leading contributor to the global burden of disease, as measured in the years of life and productivity lost due to premature mortality and disability.

So I would never wish to glorify or romanticize mental illness. And yet, having overcome a onetime diagnosis of schizophrenia and having subdued my depression and psychosis, I now live a fruitful life and recognize that for some of us mental illness can offer advantages, most notably in the realm of the imagination.

William Wordsworth, the Romantic poet, found that his recollections of early childhood offered him a glimpse at the sublime and stimulated his creativity. He suffered from deep depression, but that depression never impaired and may have even heightened his memory and imagination.

One might wonder how this could be. Doesn't depression debilitate an individual? Yes, it does. It hindered my concentration level for years and denied me pleasure as a reader, an activity that requires intense concentration. However, it has never thwarted my memory or imagination.

Wordsworth and I are not alone in this regard. Think of the poet Robert Lowell or USC Law Professor Elyn Saks, both of whom have remembered their psychotic breaks.

Could it be that depression, even of a psychotic and/or manic variety, functions as an evolutionary adaptation? Yes, I believe that this can be true, though a recent New York Times piece by Dr. Richard A. Friedman casts doubt on this theory.

There is no denying that depression destroys lives, but it can also shield some people from more severe tragedies, a point I made in writing about the recent Lars von Trier film, Melancholia. In that film, the depressed protagonist, played by Kirsten Dunst, was the only one with the imagination to cope with and arguably combat the possible destruction of the planet.

Like all adaptations, depression begins to percolate at a subconscious level. While I hope never to face the annihilation of the planet, I have faced life-threatening situations when I was deeply suicidal. With a bit of luck, some fortitude and a penchant for survival, I overcame those threats.

On a more mundane level, I have been told that I sometimes tune out people. I have not typically been aware of that, but it is clear to me that tuning out has been a defense mechanism against trauma that I suffered in childhood, trauma that was exacerbated by a genetic predisposition toward depression, psychosis and suicide.

I don't know if I fully accept the notion that what doesn't kill you makes you stronger. It is a bit of cliché, since many people who survive mental illness are irreparably damaged by it. As Bob Dylan wrote in "Mississippi," a soulful ballad from Love and Theft, "The emptiness is endless, cold as the clay. You can always come back, but you can't come back all the way."

As usual, Dylan is right. You can't come back all the way. Wordsworth had that wisdom too. Indeed, he may have been thinking about the detrimental effects of depression and growing up when he wrote, "The things which I have seen, I now can see no more."

I too realize that, while I have tamed my mental illness, there are some things that I will never be able to do because of my condition. That is fine with me. I accept that, since the things that I can do offer me exquisite pleasures, not least of which is helping to dispel stereotypes about those who suffer from mental illness.

For more by Robert David Jaffee, click here.

For more on mental health, click here.

Need help? In the U.S., call 1-800-273-8255 for the National Suicide Prevention Lifeline.