I just listened to a recent edition of ABC Radio National’s All in the Mind on evolutionary approaches to mental illness. While the topic isn’t new, it’s interesting that the two clinicians try to directly apply some of the ideas to their work treating patients with mental disorders.
Almost all evolutionary accounts of mental illness attempt to explain why we still have mental illness when it so markedly reduces the chances of reproductive success.
Most theories, and indeed the ones discussed on the programme, argue that in small doses the genes that raise risk for mental illness are useful in promoting creativity (e.g. psychosis / mania), maternal withdrawal (e.g. in post-pregnancy depression), self-preservation (e.g. anxiety) or some other presumably adaptive behaviour in specific situations.
I’m fairly tolerant of these theories, on the basis that they’re hard to demonstrate but plausible, but I have less time for Paul McClean’s ‘triune brain’ theory which one of the interviewers seems to favour.
In fact, everytime I hear the phrase ‘reptilian brain’, I reach for my spear.
This is often invoked in discussions about evolutionary psychology as a seemingly more sensible alternative to Freudian theories.
What makes me chuckle is that they are remarkably similar. Freud argued that we are a subject to evolutionary ancient drives of the Id that must be controlled by the Ego, McLean suggested that we are a subject to evolutionary ancient drives of the reptilian brain that must be controlled by the neocortex.
For an updated and significantly more sophisticated version of these arguments, neuroscientist Jaak Panksepp’s 2002 article [pdf] on the weakness of evolutionary psychology without neuroscience is well worth a read.
While we’re on the subject, distinguished biologist and sufferer of depression Lewis Wolpert recently published an open-access article on ‘Depression in an evolutionary context’ which is well worth a look.