Sunday, February 21, 2010

Brain Science Podcast 62: Warren Brown on “Did my neurons make me do it?”

I was listening to this podcast as I was going back and forth to my learning team meeting today and found it to be very interesting in how Warren Brown, author of Did My Neurons Make Me Do It?: Philosophical and Neurobiological Perspectives on Moral Responsibility and Free Will, conceives of the mind and consciousness. He seems very close to my own view.

As a precursor to this podcast, it might help to listen to Podcast #53: “Did My Neurons Make Me Do It?”, in which they discuss the book that informs this more recent episode.

BSP-62: Warren Brown on “Did my neurons make me do it?”

Warren Brown and Nancey Murphy

Warren Brown and Nancey Murphy

Episode 62 of the Brain Science Podcast is an interview with Warren Brown, PhD, co-author (with Nancey Murphy) of Did My Neurons Make Me Do It?: Philosophical and Neurobiological Perspectives on Moral Responsibility and Free Will. This book was discussed in detail back in Episode 53, but this interview gave me a chance to discuss some of the book’s key ideas with Dr. Brown. We focused on why a non-reductive approach is needed in order to formulate ideas about moral responsibility that are consistent with our current neurobiological understanding of the mind.

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One of the things I found useful in the discussion was his philosophical stance, which he terms nonreductive physicalism:
The book’s main premise is a philosophical position called nonreductive physicalism—which is a mouthful, I know. The physicalism part means that it’s really not necessary to add some additional entity—a mind or a soul—to account for human capacities, human distinctiveness, the humanness of persons; that there is sufficient complexity in our physical systems to account for that.

And then the non-reductive part means that there are properties of us as whole persons, as whole physical beings, that cannot be accounted for on the basis of the properties of neurons, or molecules, or atoms: That there are what are called emergent properties, and that those are sufficient to describe and account for our humanness, including things like free will, or moral agencies making moral decisions, being social and moral persons.
In general, the authors tend to reject the idea of "nothing buttery" - the notion that mind and consciousness are nothing but atoms and molecules, neurotransmitters and electrical impulses. This "nothing but" approach is what most of us mean when we talk about neuroscience being too reductionist in its approach to mind.

I appreciate that qualification - Brown favors an emergence perspective for mind - but this is the section that appreciated the most:
Dr. Campbell: Warren, let’s get into some of the meat of your book. You said in the book at one point that you had to attack (I think you used the word ‘attack’; I apologize if that’s an exaggeration) two very prevalent world views—causal reductionism and the idea of the mental as inner. Can you address why those would need to be attacked?

Dr. Brown: Causal reductionism just does not work, because it’s basically dehumanizing that every causal process is down to the level of atoms and molecules—that humans per se are nothing but vibrating molecules, and all the rules and everything that moves us forward in the world are entirely determined at the level of lower processes, so that causal reductionism means all the causes are down there at these micro levels.

And if you have that, rationality doesn’t make any sense, ethics doesn’t make any sense, because any ethical thought or rational thought you would have could not be judged by truth or social ethics. It would just be the outcome of things happening at the level of molecules and atoms. So, causal reductionism is just problematic.

Dr. Campbell: The idea of mental as being inner.

Dr. Brown: Yes. As soon as you have mental as describing things inside of me, you have lapsed back into (whether you intended to or not) a mind-body or a body-soul sort of dualism, as if there are two things going on—one which is an inner autonomous separate event and one that is an outer bodily event. And so, we just thought that the idea of mental as inner was problematic.

I would say (I don’t remember if we said this in the book; we might have) the idea of mind is basically a verb. It’s not a noun. And we get ourselves trapped by using ‘mind’ as a noun. Minding—doing complex sorts of interactions with the world that we call mental—are in fact ways we interact with the world. They’re ongoing processes. We don’t have ‘a’ mind. As soon as you have ‘a’ mind, then you’ve got to figure out where is the mind, and that’s where you get into this problem of the mind being inner.

Dr. Campbell: You use a phrase in the book that’s very important—top-down causation. And I know when I was reading the book, my first reaction to that was very negative. I was expecting God around the corner, to be honest with you. But then I read carefully what you wrote, and realized that wasn’t what you were talking about. Can you talk about how you use the phrase ‘top-down causation’?

Dr. Brown: There are several ways that ‘top-down’ is rightly used with respect to humankind and us as embodied persons. One is probably better described as sort of levels of complexity: the more complex system as a whole constraining or influencing the less complex parts. It’s sort of a part-whole relationship. The whole constrains all the parts.

In that sense we don’t mean top-down in the sense of top-down in a company, where the executive is at the top, and the executive sends a command down that tells some other member of the organization to do X or Y. That would necessitate some kind of an inner agent that was different than the person as a whole. So, part-whole, or the constraint of the smaller parts with respect to a system as a whole, is the best way to understand that part-whole.

Now, there is a form of top-down that kind of works down the nervous system, from the cerebral cortex down through the midbrain, and the brainstem, and the spinal cord. And in that sense there is a sort of a hierarchical top-down. But these levels are so tightly coupled that what happens in the cortex kind of has no existence or meaning without tight coupling with the brainstem, or the midbrain, or the spinal cord.

So, even though you kind of have a hierarchical system in the nervous system, and in that sense some kind of a top-down from the cerebral cortex down, it’s much more tightly coupled than having an independent agent, or autonomous agent at the top commanding everything down below it.

Dr. Campbell: Right.

Dr. Brown: So, there are two ways that we would think about top-down, but that second way I’m talking about can be distracting if you don’t credit the tight coupling in the entire nervous system, and the nervous system with the entire body.

Dr. Campbell: Yes, if you don’t take that into account, the fact that in the sensory system there’s like 10 times as much feedback downward as there is feedforward signals wouldn’t make any sense at all.

Dr. Brown: Right. That the cerebral cortex, for example, in the visual system sorts visual information. Not everything that comes into the eye gets passed on or processed in the cerebral cortex. And attention and other kinds of expectancies have a lot to do with what the visual system processes. But this merely means that they’re tightly coupled together. They don’t operate independently.

So, it’s not like the frontal cortex, for example, is an autonomous agent governing and pulling the strings to what happens in the posterior visual system, but these are just very much integrated into one processing unit. It’s just that the things that the frontal cortex, for example, does—at least in terms of informational complexity—kind of operate at a higher level.
And then there is this section, which gets into the idea that consciousness is embodied (and encultured) and is not simply located in the brain:
Dr. Campbell: So, that sort of leads into the next thing I wanted to talk about, which is the problem of replacing mind-body dualism with brain-body dualism.

Dr. Brown: Yes. A lot of the way that we loosely talk about the brain is as if all of mental activity is simply brain processes, and therefore what we used to call the mind is now the brain, but it’s in some sense independent of, or sort of residing in this body, and controls it as some kind of an autonomous agent that controls the body that it’s nested in.

And one of the ways that I think this gets sort of processed in philosophy is these ideas of a brain in a vat—as if the brain can be separated from the world and be intelligent at all. I just think it’s a non sequitur. It’s a meaningless mental experiment to think about a brain in a vat, because a brain in a vat without a body just can’t have meaningful information to start with.

It can’t be intelligent, because we’re intelligent because we interact with the world bodily. Our bodies are part of our sensory systems, and part of our emotional feedbacks, and all kinds of things. We just don’t have any information without being able somehow to interact with the world.

And when I think I’m thinking offline (you know, I’m sitting in my chair, I’m really not doing anything here, I’m just sort of thinking about things) I’m basically rehearsing actions in the world from memory. I’m rehearsing conversations, creating possible conversations, imagining possible actions, but all accessed out of memories of real actions in the world in the past.

You mentioned people like Raymond Gibbs. Raymond Gibbs talks about this a lot. Andy Clark talks about this a lot—about the degree to which our intelligence is really an embodied intelligence. It’s not an abstract thing sitting in the brain—that the brain can be intelligent on its own.

Dr. Campbell: Yes, you had that great quote in the book (and I don’t remember who it’s from): ‘The mind is embodied, not embrained.’

Dr. Brown: Yes. That’s a term we have used and others have used. Yes, exactly. And it’s not just embodied. Andy Clark really says we’re sort of encultured, in the sense that he says we make the world smart so that we can be dumb in peace.

And a lot of our intelligence is scaffolded out in things that we either construct or our culture has constructed for us out in the environment. We, as intelligent beings, are pretty tightly coupled with our social and cultural environment. So, in that sense we’re embedded as well as embodied.
Go listen to (or read) the whole podcast - Dr. Campbell is a great interviewer and her position on neuroscience and psychology is philosophically similar to the material I post here regularly.


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