The last issue of the journal Progress in Neuro-Psychopharmacology and Biological Psychiatry has a very interesting special issue on how evolutionary theory and psychology can be integrated into psychiatric theory about mental disease. It’s also called “evolutionary psychiatry“.
OK, you might ask; we can accept that evolutionary theory can explain why we behave as we do today, i.e. normal cognition and behaviour. But psyhiatric disease? Is this an attempt to explain the evolution of a disease? The straightforward answer is a resounding “no”. Evolutionary approaches to disease – including mental disease – is an attempt to describe and explain the design characteristics that make us susceptible to the disease (from Nesse & Williams, 1996). The evolutionary trajectories of humans is far from a travel towards perfection. We are full of errors and somatic and mental shortcomings – and the appendix, near-sightedness, and a bottleneck attentional system and the like are examples of this.
Another important issue is that the border between normal and abnormal psychology is becoming increasingly muddled. That may sound as a problem, but it’s actually caused by a change in our understanding of how our minds come to be, and especially how normal variation extends into pathological domains. In this sense, it’s hard to draw waterproof boundaries between normal and abnormal psychology. We work on a continuum, and the branch of modern evolutionary psychiatry makes a good case for such an approach.
Here is the introduction by Dan J. Stein:
Darwin wrote extensively on the implications of evolutionary theory for understanding human psychology, and made a special effort to gain access to observations on the insane. Pioneering ethologists, such as Tinbergen, emphasized the value of their work for understanding psychiatric disorders. Today, evolutionary psychology has become an accepted scientific field, and the area of evolutionary psychiatry has similarly shown increasing maturity. This special issue of “Progress in Neuropsychopharmacology and Biological Psychiatry” provides an opportunity to review some of these developments.
An introductory paper by Stein summarizes some of the history of evolutionary psychiatry in general, and considers its application to psychopharmacology in particular. Panksepp then outlines a number of conceptual issues at the heart of evolutionary psychiatry, arguing that there are flaws in much of the work that has been undertaken in evolutionary psychology and psychiatry, and proposing a novel way forwards. These introductory papers emphasize the possibility that the focus of evolutionary psychiatry on distal mechanisms can be usefully integrated with advances in our understanding of the proximal mechanisms that underpin psychopathology.
Several of the contributions in this issue go on to exemplify the application of the constructs of evolutionary psychiatry to particular mental disorders. Crow and Burns put forward different evolutionary approaches to schizophrenia, Allen and Badcock review evolutionary approaches to depression, Bracha focuses on the anxiety disorders, Feygin and colleagues on obsessive-compulsive disorder, and Baron–Cohen on autism. Although there are important challenges for evolutionary psychiatry going forwards, as the sophistication of its concepts and methods increases, so likely will its influence on the understanding of psychopathology.
A number of authors in the area of evolutionary psychiatry are also interested in more fundamental issues in evolution of brain and behavior. Thus, Crow is crucially concerned with the evolution of language, Burns emphasizes the evolution of social cognition, Baron–Cohen’s work touches on the importance of gender differences in systematizing and empathizing abilities, and Feygin and colleagues’ work addresses the evolutionary bases of religious ritual and loving attachment. Indeed, there is an argument that fundamental progress in evolutionary theory will be reliant on the resolution of key questions about mind and its illnesses.
-Thomas
Could’nt read the Journal article as it needed subscription, but found the link to “evolution psychiatry” very educative. While many see evo psychologists as devoting much time to inconsequential and obvious issues like “why rich men and beautiful women are attractive to the other sex”, these articles point to a new direction of research that has important implications for psychology. Would love to see more content on group selection, social mind and mate selection and thier contribution to pathology/ normalcy. Also was wondering if the four Archetypes as on the “evolution psychiatry: link need to be revisited and aligned with the five-factor theory of Personality.
regards,
Sandy G
Hi Sandy,
I could not agree more. Evo-psychology seems to focus too much often on the obvious. Of course, the nitty-gritty details need to be sort out, and they may occasionally provide surprising results. But this is a refreshing use of evolutionary thought.
-Thomas
Evo-psychiatry
Brain Ethics has just picked up on the recent development of “evolutionary psychiatry” (evo-psychiatry for short) that aims to understand mental disorder in terms of how we have evolved to become susceptible to disabling thought and behaviour pattern…
Randy Nesse actually does argue that depression is an adaptation that happens in response to loss (depression in grief) or status loss (other depression). He bounces back and forth between whether he means that low mood is an adaptated response and depression is a pathological form, or whether he really means that depression is an adapted response.
I have also read evolutionary theory suggesting that bipolar disorder is an adaptation (for increased offspring or migration in the spring) but I can’t remember the source. (And I don’t actually think it’s accurate.)
Evpsych does sometimes say that certain things aren’t really disorders because they’re adaptations, and when reading that, even if you take it to be true, it’s important to keep in mind that adaptations can be incredibly bad for you. Take, for example, sickle-cell anemia. Protects against malaria, but also messes you up.
Nesse; sounds interesting, and interesting about his indecisiveness.
Bad adaptions: thanks for pointing this out. Many people have the impression that evolution leads to improvements only. So, in the case of sickle-cell anemia, we could think of psychopathology in the same vein. Cognitive adaptions that have come to be to support certain functions, can have backsides that lead to great suffering. And still be “normally” evolved.
-Thomas
[...] Great summary of evo-psychiatry here. Thanks again to Brain Ethics. I would read all of this if I had the time or mental ability ; ) [...]
Hi Everyone,
AThe note above about my work on evolution and mood disorders is interesting. My position is that the capacity for mood is useful and none of us are in a position to decide when depression symptoms are normal or abnormal until we understand the situations in which symptoms of low mood/depresison are useful. I try to avoid using the word “depression” because many people automatically presume that it refers to a pathological state.
Why genes for bipolar disease persist is a whole separate question from the question about why mood exists, but they are related because I expect bipolar disease arises from dysregulaion of normal mood. For those interested, I have a new chapter from the APA handbook of evolution and depression on my webpage. There is also an overview of evolutionary psychiatry that I wrote for the Handbook of Evolutionary Psychology. Comments welcome.
Randy
Dear Randy,
Thanks a lot for pointing this out to us. I’ll read up on your most interesting work after resurrecting my computer to a fully working state (to all, a total computer havock has caused a prolonged period of no blog-posting from me).
The link to Prof. Nesse’s homepage is: http://nesse.us/
Best,
Thomas
Dear Thomas,
I wonder if your position on evolutionary psychiatry (a resounding “no”) evolved from the time of original publication more than 3 years ago. I’ll be happy to read an update.
Cordially,
Michael Levin, MD
I guess I can call myself an evolutionary psychiatrist.
Hi Michael,
Not sure whether I’d have any position on evo-psychiatry at all, just noted the issues with the approach. I’m probbaly not qualified to judge this, but my issue would be that we should be careful with any evolutionary explanation, as it from a logical standpoint may so easy become retrofitting.
-Thomas