Mentalization and borderline personality disorder (part two)

Sigmund Karterud is a pioneer of group therapy for borderline personality disorders. He focuses on mentalization: our ability to understand ourselves and other people in terms of mental phenomena – beliefs, feelings, wishes, and hopes. In the second part of our interview, Sigmund explains the evolutionary relevance of Mentalization-Based Group Therapy. (Read Part one of Sigmund’s interview here.)

In a previous article you wrote for the OUPblog, you said some interesting things about the evolutionary reasons behind mentalization; about the way in which the ability emerged. Could you say a little about how, as a phenomenon, it came into existence?

Sigmund Karterud: The word ‘mentalizing’ refers to the ability to think, in mental terms, of the reasons for behavior; for your behavior and mine, and for the interaction between us. For example, that I am able to see that you behave [in a certain way] because you are hungry, you are angry, you are driven by sexual lust.

There are mental intentions behind your behavior, but the issue here is that those intentions are more or less opaque; they are not written on your forehead. So I have to interpret why you behave in a certain way, and my interpretations can be wrong. This ability to infer why people behave as they do is mostly taken for granted, it’s so obvious, but of course this ability evolved at some point and for some reason.

There’s a lot of interest around this subject at the moment, and what exactly the differences are between chimpanzees’ mental functioning and humans’, especially a child’s mental functioning. Do chimpanzees interpret other chimpanzees? Do they even think?

You can interpret another person in an intuitive way, and when you do, you don’t think about it too much. That’s called ‘implicit mentalizing’. ‘Explicit mentalizing’ (the opposite of implicit) is when I’m saying to myself, ‘the reason for your behavior is so and so’. It is a linguistically based capacity. I need language to speak to myself in such a way, so explicit mentalizing must be linked to the evolution of language.

When did we start to communicate in linguistic terms, or with sounds and gestures, such as those used by the Great apes? Of course they have a rather sophisticated communication, but it’s when you move to a linguistic form that the possibilities are far greater. In evolutionary terms, that’s linked to the question of when the brain developed areas responsible for linguistic concepts. The question for us is, how did the brain change in order for us to articulate; and what were the reasons for these developments?

The kind of explanatory direction I support is that developments in group complexity demanded more social cognition. That sets all of this up to happen. The more complex, social and organizational interaction is, the more rewarding it is for you and me. If I’m able to interpret my neighbour and the other members of the group, then I can become smarter.

So, the evolutionary driving force for mental capabilities is not to avoid danger from wild animals. It is for social cooperation, perhaps for hunting, which is necessary for the development of the group from a scattered family to complex group dynamic, a dynamic that remains today.

Featured image: Cave of the Hands by Mariano. CC-BY-SA-3.0 via Wikimedia Commons.