Sunday, February 28, 2010

Silver Lining?

Jonah Lehrer has an excellent article in today's New York Times Magazine about a new way that a psychiatrist and an evolutionary psychologist, Paul Andrews and Andy Thomson, are thinking about depression, or at least one of its features - rumination. If it such a widespread condition, they ask, then is it possible that it is somehow adaptative? Don't worry, both the article and the scientists are not belittling the pain of being depressed.

Lehrer explores their idea that rumination, which is typical to the grief reaction, is more than simply pessimism, it is also the kind of extended expenditure of mental energy on a problem out of which can be born new understanding. The ruminative feature resembles a part of the cognitive process that often results in successful creations. I would add my thought that, in a situation of pain or loss, the lack of interest in activity, food, or sex, keeps one physically passive at a time when the prediction-making part of us does not have the optimal setting for activities requiring good coordination and fast reaction-time, and we may therefore make bad judgments. So instead our body demands that we sit, collect, and turn things over. This could also be another adaptive feature of the mechanism. Lehrer also gives space in his article to discuss the criticisms many psychiatrists have of this new notion.

I would have appreciated brief inclusion of the current theories of what is happening not just in the psyche, but in the brain, during depression. One theory receiving a lot of attention is that of reduced neurogenesis (less creation of new neurons) in certain parts of the brain. I wonder how this correlates with or contradicts Andrews and Thomsons hypothesis? Their idea began with the prevalence of depression, which Lehrer describes as 7 percent. Is that a world-wide statistic? A Western society statistic? An American statistic?

I have often heard the construct of depression critiqued as an illness of wealthy privileged societies. That made me think two things: a) adaptation occurs by random mutation (although it's the Natural Selection part that people most like to focus on) and, b) the notion of which features are adaptive for humans needn't be monolithic. Humans haven't all evolved to one perfect homogeneous species and stopped. We are evolving many different features. Some of us are hairy, some smooth. We have different pigments shading our skin, which were adaptations to different environments. We have different length femurs, so why not different cognitive styles? Most of us are no longer hunters and gatherers. Perhaps we are becoming aware of a random mutation that gives us a different default setting for our prediction-making organs (our brains) to favor periods of less action, less reproducing, and more rumination. Perhaps in certain contexts in which humans live this will make us more adaptive and therefore it will survive over the long run. Perhaps the features of it that are maladaptive in other contexts will result in it disappearing over millenia. We won't be around to find out. But I am glad for Lehrer's thoughtful look at scientists who are trying to look at a cultural and scientific phenomenon with a longer view. I always admire his writing and, as usual, this piece gives us insight into novel thoughts about topical issues of mind and psyche. It also rekindled in me some thoughts about our society's knee-jerk propensity to always value happiness above grief, anger, passion, or doubt. We have a range of affective states. Perhaps each part of that range has its uses.


Pete said...

Ted, thanks for pointing me to this article which I found very interesting indeed. I agree with you that it would have been helpful to read more on the neuroscience of depression. I can't remember if Lehrer responded to the neurogenesis question on his blog. As for the statistics, it's interesting that in South Africa (where I live), a recent Mental Health and Poverty study suggests that depression is much more prevalent in poorer communities than previously thought.

Ted said...

Hi Pete- Glad you got a look at it. JL had a series of posts on his blog over the course of last week, addressing various criticisms (unsurprisingly).