What’s wrong with my homunculus?

My homunculus is tired of being dismissed so casually. In neurology, we’re introduced to the Homunculus in reference to body maps in neuroanatomy. For example, there’s a map of the body superimposed on the motor cortex, the part of the cerebral cortex that initiates the final common pathway for volitional movements from the cortex to the muscles, The maps a funny one, being upside down and distorted so that the regions with the greatest control (face and hands) take up largest area:

Motor Homunculus

There’s a neat 3D model of what this distorted little man would look like:

Motor Homunculus Model

There’s a similar somatosensory map for touch sensation from the skin. These funny looking little men are the internal representations of our body in the brain.

I’m reading Alison Gopnik’s excellent book The Philosophical Baby. She does a great job of tackling some real philosophy in the context of developmental neuroscience and psychology. But like lots of scientists, when up against that very difficult barrier of materialism and functionalism, she bails.

I’ve pointed out before that materialists, faced with a complete inability to explain the subjective feeling of consciousness turn into dualists, asserting that only the brain can exist. Yet they can’t help speaking of mind as something that exists even while implying it can’t exist as it is not material and can’t be pointed at; only the brain can is.

We know that there are models of the body in the brain. The motor homunculus is a well established example. It is the motor map in the cortex. It seems clear to me that I experience voluntary movement through that map. It is the homunculus and I don’t need another map to control that map. There are also maps of the world in the brain. Maps of concepts like the analogous ideas of distance and addition of numbers

The existence of the motor homunculus doesn’t mean there’s a little man sitting on the motor cortex controlling movement. Its the cortex that’s doing the work. It is organized as a map of the body.

When she dismisses out of hand the concept of the homunculus, Gopnik makes the mistake of confusing the general concept of a homunculus with an infinite regress. That’s the fallacy of the little man controlling movement. If I have a little man in my head, then that little man needs a little man to control him and on into an infinite regress.

Many also confuse the concept of a homunculus with dualism. Certainly a theory that requires a separate homunculus, a little man that controls movement or who sees what is projected into the brain isn’t useful.. This kind of dualism accounts for consciousness but is unacceptable because it has no explanatory power.

The tough question is how does mind, consciousness, arise from its substrate, brain.

There’s a common misunderstanding of John Searle’s Chinese Room argument mostly made by materialists. Searles argues strongly and directly against materialism, believing as I do that mind exists and must itself be explained. It is a different level of analysis of the material world, the way hardness or smoothness of rocks can’t be explained solely with reference to reductionist information from inorganic chemistry. Hardness and smoothness are systems level qualities that are dependent on the chemistry, not explained by it. Similarly mind is dependent on brain, not explained by it.

In the Chinese Room argument, a translator appears the same to an outside observer whether or not he understands the language or is just looking up phrases in a big book. This demonstrates that information about function can’t distinguish between the conscious and the mechanical. Materialist explanations, without reference to a larger systems level examination are missing something. Mind is something different from the functional activity, here for example translation. It can be done with understanding or without understanding The brain need not itself be conscious to generate the events. The substrate can be aware or not aware in the black box.

The difference between the translator that knows chinese and the one who is translating mechanically without awareness is understanding.

So I’ll point to my motor homunculus as one part of the brain that I know my mind is dependent on for fine voluntary movement. I can’t yet point to where Searle’s Chinese Room argument is modeled in my brain. Sorry.

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