Evolution of the troubled mind

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.

Link on AITM on evolutionary approaches to psychiatry.
pdf of Panksepp’s article on ‘neurevolutionary psychology’.
Link to Wolpert’s article on evolution and depression.

3 thoughts on “Evolution of the troubled mind”

  1. Sammie: Programme?
    Sinclair: We’re not in Kansas anymore.
    Eric Y. (bored and perceptive) : I’m sure you have a question for the noted anthropologist, Sammie.
    Sammie (directing his attention towards Jay Whitlow) : Okay. Height is normally distributed.
    Jay Whitlow: Yes, Sammie, physical attributes are often normally distributed.
    Sammie: And intelligence is normally distributed.
    Jay Whitlow: Yes.
    Sammie: Is intelligence a physical attribute?
    Eric Y. (suddenly more interested) :The brain is a physical structure.
    Sammie: So is sanity also normally distributed?
    Jay Whitlow: Assume sanity IS normally distributed. Most of us are in the middle with both extremes represented roughly equally. Does this lead to any unusual conclusions?
    Sinclair (with a flash of insight that is purposly hidden by his condescending nature) :”Sanity” is socially constructed, so it would be “defined” by the middle of the curve. So both extremes would be “insane”. The “sane” cannot be “insane”, a contradiction.
    Jay Whitlow: Good.
    Sammie: So what is the distribution?
    Sinclair (looking around) :When are we going back to Kansas?

  2. The Triune brain hipothesis also makes me bother. It is as if evolution does not take into account what already exist and proceed from scratch forming new cortical sheets without connection between each other. The confusion arised as a consequence of bad and misguided evolutionary arguments from the time of the mayor nomenclatures of the XVIII, XIX and the beginning of XX century¬¥s anatomy, such as those of Brodmann, Von Economo, Vogt and Vogt…
    On the other hand, i think evolutionary psychology is most of the time trapped in wishful thinking. How can be proved many of its conclusions about past evolutionary enviroments and their selective pressures causing the appearence of new adaptive traits?
    New mergings such as neuroevolutionary psychology or evolutionary cognitive neuroscience are the best way to fill the gap.

  3. Mental illness is non-physical. If it were physical the illness would be treated by a neurologist.
    Mental illness unlike an broken bone, infection or cancer , lasts the rest of the patients life (so say the diagnosticians-psychiatrists)
    Mental illness is still real, as emotions and thoughts are real to the individual.
    There will always be mental illness.
    But playing along with the idea of mental illness is a defective brain and bad DNA, after the Nazis killed 250,000 genetically “bad” people in Action T4 during WW2, was there a measurable reduction of mental illness in the countries they controlled? I think not.

Leave a comment