Here’s the deal: Depression is endemic in the population. Every year, seven percent of us get taken down by what William Styron described as a “gray drizzle of horror ... a storm of murk.” But:
If depression was a disorder, then evolution had made a tragic mistake, allowing an illness that impedes reproduction ... to spread throughout the population.
So does depression have some kind of secret purpose, like a fever that helps the immune system fight off infection? Enter Andy Thompson and Paul Andrews, a psychiatrist and evolutionary psychologist respectively from the University of Virginia, who came up with the “analytic-rumination hypothesis.”
Start with the proposition that depression is characterized by over-ruminating. Our brain gets locked into “a recursive loop of woe.” We can’t think about anything else. What is good about that?
Nothing, according to prevailing opinion, which strongly suggests that our malfunctioning brains are genetic accidents.
But the evolutionary perspective forces us to consider depression as an adaptation (however painful) to our environment. We typically ruminate in response to a bad setback, such as death in the family or loss of a job. A rumination about a bitter divorce may take the form of regret, second-guessing, and concern about the future.
These are the type of thoughts that fuel depression, which meds and talking therapy aim to stop dead. But suppose this type of rumination forces us to focus on the things we need to be dealing with right now? To learn from our experience and reject the type of rationalizations that may have gotten us into this very type of mess in the first place? So, quoting Andrews:
I started thinking about how, even if you are depressed for a few months, the depression might be worth it if it helps you better understand social relationships. Maybe you realize you need to be less rigid or more loving. Those are insights that can come out of depression, and they can be very valuable.
Bullshit, says Peter Kramer, author of "Undoing Depression." Depression sucks, and that’s all there is to that. How does the hypothesis account for chronic depression, for instance? Or late life depression?
Ed Hagen, an anthropologist at the University of Washington who is sympathetic to the hypothesis, also has some quibbles. For instance, individuals with major depression often don’t groom, bathe, or sometimes even use the toilet. This is one helluva price to pay for quiet reflection.
But evolutionary psychiatry and its critics are essentially coming from the same starting point. Depression is a hugely complex illness. Multifactorial and heterogeneous are the terms used to describe its many causes and seemingly infinite variations. No one theory is going to account for every single depression.
Randolph Nesse, an evolutionary biologist at the University of Michigan, offers a list of possibilities (see Darwin and the Psychiatric Advantage and Randolph Nesse Interview), including a plea for help, signal of defeat (to prevent future attacks), and removing the rose-colored glasses. Nesse compares depression to pain, which can arise from a variety of sources, as well as being an affliction in its own right.
In the meantime, though, something observable is going on in the brain. Researchers investigating depressed individuals have picked up heightened activity in the ventrolateral prefrontal cortex (VLPFC), which is especially important for maintaining attention. (Deficits in the VLPFC have been linked to ADHD.) One possibility is the VLPFC underlies rumination, allowing individuals to stay focussed.
The downside to this type of focus is individuals are too wrapped up in their own shit to concentrate on other things, such as work and relationships or even the most basic cognitive tasks. But, “human attention is a scarce resource — the neural effects of depression make sure the resource is efficiently allocated.”
Moreover, “if depression didn’t exist — if we didn’t react to stress and trauma with endless ruminations — then we would be less likely to solve our predicaments. Wisdom isn’t cheap, and we pay for it with pain.”
This same unrelenting focus may help account for the unbelievable creativity found in the depressed population. As neuropsychiatrist Nancy Andreasen of the University of Iowa describes it, “if you’re at the cutting edge, then you’re going to bleed.”
In the meantime, there is a growing body of opinion that meds may interfere with the rumination process. Yes, there is a use for meds, but the high relapse rate (76 percent according to one study) when antidepressants are discontinued indicates a host of underlying personal problems that haven’t been resolved.
Even strong supporters of antidepressant therapy acknowledge that these meds are treating the symptoms rather than the cause. But do we do nothing while over-rumination works its destructive course? Of course not. Certain kinds of talk therapy are extremely helpful, and further refinements may speed up the rumination process.
Often, when the ruminator solves his or her problem and comes to a decision (such as to find a new career), the depression lifts. But can we afford to wait that long? As the article concludes:
To say that depression has a purpose or that sadness makes us smarter says nothing about its awfulness. A fever, after all, might have benefits, but we still take pills to make it go away. This is the paradox of evolution: even if our pain is useful, the urge to escape from the pain remains the most powerful instinct of all.
Posts
