Jonah Lehrer writes today in The New York Times about the evolutionary upside of depression.
Andy Thomson is a psychiatrist at the University of Virginia. Paul Andrews is an evolutionary psychologist at Virginia Commonwealth University. In July they published their ideas in the Psychology Review.
The article is interesting–maybe entertaining–but I’m suspicious of it. Too much anecdote and too little science. It is the type of article that’s easy, and feeds popular misconceptions about depression. For example, it pits anti-depressants against talk therapy. Research shows the combination of both therapies, yields the best results; it is not one versus the other.
I’ve posted several quotes from it below. If you’ve read my posts, you know I’m a fan of Peter Kramer, and he is quoted below, critical of Andrews and Thompson’s hypothesis.
The persistence of [depression] — and the fact that it seemed to be heritable — posed a serious challenge to Darwin’s new evolutionary theory. If depression was a disorder, then evolution had made a tragic mistake, allowing an illness that impedes reproduction — it leads people to stop having sex and consider suicide — to spread throughout the population. For some unknown reason, the modern human mind is tilted toward sadness and, as we’ve now come to think, needs drugs to rescue itself.
The alternative, of course, is that depression has a secret purpose and our medical interventions are making a bad situation even worse. Like a fever that helps the immune system fight off infection — increased body temperature sends white blood cells into overdrive — depression might be an unpleasant yet adaptive response to affliction. Maybe Darwin was right. We suffer — we suffer terribly — but we don’t suffer in vain.
Is this a useful analogy? We do use medication to attack the fever and underlying cause. Analogously, we should fight depression, medically, the symptom and the underlying infection. It is not clear, for example, that prozac is only attacking the symptom. It also may be helping repair the brain at the neurological level. And yes, I do advocate talk therapy to also address and the underlying cause as well.
The bleakness of this thought process helps explain why, according to the Yale psychologist Susan Nolen-Hoeksema, people with “ruminative tendencies” are more likely to become depressed.
The capacity for intense focus, [Andrews and Thomson] note, relies in large part on a brain area called the left ventrolateral prefrontal cortex (VLPFC), which is located a few inches behind the forehead. While this area has been associated with a wide variety of mental talents, like conceptual knowledge and verb conjugation, it seems to be especially important for maintaining attention. Experiments show that neurons in the VLPFC must fire continuously to keep us on task so that we don’t become sidetracked by irrelevant information. Furthermore, deficits in the VLPFC have been associated with attention-deficit disorder.
Human attention is a scarce resource — the neural effects of depression make sure the resource is efficiently allocated.
. . . rumination is largely rooted in working memory, a kind of mental scratchpad that allows us to “work” with all the information stuck in consciousness. When people rely on working memory — and it doesn’t matter if they’re doing long division or contemplating a relationship gone wrong — they tend to think in a more deliberate fashion, breaking down their complex problems into their simpler parts.
The publication of Andrews and Thomson’s 36,000-word paper in the July 2009 issue of Psychological Review had a polarizing effect on the field. While some researchers, like Jerome Wakefield, a professor at New York University who specializes in the conceptual foundations of clinical theory, greeted the paper as “an extremely important first step toward the re-evaluation of depression,” other psychiatrists regarded it as little more than irresponsible speculation, a justification for human suffering. Peter Kramer, a professor of psychiatry and human behavior at Brown University, describes the paper as “a ladder with a series of weak rungs.” Kramer has long defended the use of antidepressants — his landmark work, “Listening to Prozac,” chronicled the profound improvements of patients taking the drugs — and criticized those who romanticized depression, which he compares to the glamorization of tuberculosis in the late 19th century. In a series of e-mail messages to me, Kramer suggested that Andrews and Thomson neglect the variants of depression that don’t fit their evolutionary theory. “This study says nothing about chronic depression and the sort of self-hating, paralyzing, hopeless, circular rumination it inspires,” Kramer wrote. And what about post-stroke depression? Late-life depression? Extreme depressive condition? Kramer argues that there’s a clear category difference between a healthy response to social stressors and the response of people with depressive disorder. “Depression is not really like sadness,” Kramer has written. “It’s more an oppressive flattening of feeling.”
For Thomson, this new theory of depression has directly affected his medical practice. “That’s the litmus test for me,” he says. “Do these ideas help me treat my patients better?” In recent years, Thomson has cut back on antidepressant prescriptions, because, he says, he now believes that the drugs can sometimes interfere with genuine recovery, making it harder for people to resolve their social dilemmas. “I remember one patient who came in and said she needed to reduce her dosage,” he says. “I asked her if the antidepressants were working, and she said something I’ll never forget. ‘Yes, they’re working great,’ she told me. ‘I feel so much better. But I’m still married to the same alcoholic son of a bitch. It’s just now he’s tolerable.’ ”
The experiment itself was simple: Forgas placed a variety of trinkets, like toy soldiers, plastic animals and miniature cars, near the checkout counter. As shoppers exited, Forgas tested their memory, asking them to list as many of the items as possible. To control for the effect of mood, Forgas conducted the survey on gray, rainy days — he accentuated the weather by playing Verdi’s “Requiem” — and on sunny days, using a soundtrack of Gilbert and Sullivan. The results were clear: shoppers in the “low mood” condition remembered nearly four times as many of the trinkets. The wet weather made them sad, and their sadness made them more aware and attentive.
Joe Forgas is a social psychologist at the University of South Wales in Australia.
the virtue of self-loathing, which is one of the symptoms of depression. When people are stuck in the ruminative spiral, their achievements become invisible; the mind is only interested in what has gone wrong. While this condition is typically linked to withdrawal and silence — people become unwilling to communicate — there’s some suggestive evidence that states of unhappiness can actually improve our expressive abilities. Forgas said he has found that sadness correlates with clearer and more compelling sentences, and that negative moods “promote a more concrete, accommodative and ultimately more successful communication style.” Because we’re more critical of what we’re writing, we produce more refined prose, the sentences polished by our angst.
…depressive disorder is an extreme form of an ordinary thought process, part of the dismal machinery that draws us toward our problems, like a magnet to metal.
Randolph Nesse at the University of Michigan, say that complex psychiatric disorders like depression rarely have simple evolutionary explanations. In fact, the analytic-rumination hypothesis is merely the latest attempt to explain the prevalence of depression. There is, for example, the “plea for help” theory, which suggests that depression is a way of eliciting assistance from loved ones. There’s also the “signal of defeat” hypothesis, which argues that feelings of despair after a loss in social status help prevent unnecessary attacks; we’re too busy sulking to fight back. And then there’s “depressive realism”: several studies have found that people with depression have a more accurate view of reality and are better at predicting future outcomes. While each of these speculations has scientific support, none are sufficient to explain an illness that afflicts so many people. The moral, Nesse says, is that sadness, like happiness, has many functions.
Why did The New York Times give Lehrer so much space to this “analytic-rumination” hypothesis? Merely because it is newest?
