Friday, April 04, 2008

A Unified Theory of Consciousness


Consciousness studies are in the same place as physics when it comes to a theory of everything.

In physics, the goal is to unite Einsteinian physics with quantum mechanics. The closest solution to date is string theory (or actually M-Theory), for which there is no consensus that it is the solution. There is still an unresolved disconnect between the macro and the micro. Oh, the joy.

Consciousness is in the same bind. While the neuroscientists keep seeking new ways to explain away consciousness as a by-product of neurological processes, many others reject that reductionist view as fundamentally flawed in that it cannot explain how we understand our sense of self. Again, there is a conflict between the micro and the macro.

Recently, I mentioned that was I reading the newest Douglas Hofstadter book, I Am a Strange Loop. Although I am still early on in the book, what I see emerging is an attempt to bridge the micro and the macro through the idea of the "strange loop."

DH uses a thought experiment to explain the premise. He proposes a frictionless pool table with only sixteen balls, but very many extremely tiny marbles, called sims (small interacting marbles).

These sims bash into each other and also bounce off the walls, careening about rather wildly in their perfectly flat world -- and since it is frictionless, they just keep on careening and careening, never stopping.

.... The sims are also magnetic (so let's switch to "simms", with the extra "m" for "magnetic"), and when they hit each other at lowish velocities, they can stick together to form clusters, which I hope you will pardon me for calling "simmballs". A simmball consists of a very large number of simms (a thousand, a million, I don't care), and on its periphery it frequently loses a few simms while gaining others. There are thus two extremely different types of denizens of this system: tiny, light, zipping simms, and giant, ponderous, nearly-immobile simmballs.

The dynamics taking place on this pool table -- hereinafter called the "careenium" -- thus involves simms crashing into each other and also into simmballs. (pg. 45)

He then adds some more complexity to the system.

The vertical walls that constitute the system's boundaries react sensitively to outside events (e.g., someone touching the outside of the table, or even a breeze) by momentarily flexing inward a bit. This flexing, whose nature retains some traces of the external causing event, of course affects the motions of the simms that bounce internally off that section of wall, and indirectly this will be registered in the slow motions the nearest simmballs as well, thus allowing the simmballs to internalize the event. We can posit that one particular simmball always reacts in some standard fashion to breezes, another to sharp blows, ans so forth. Without going into details, we can even posit that the configurations of simmballs reflect the history of the impinging outer-world events. In short, for someone who looked at the simmballs and knew how to read their configuration, the simmballs would be symbolic, in the sense of encoding events. (pg 45-6)

This is his explanation for the pun of simmballs and symbols. Here is the point of this thought experiment.

Of course this image is far-fetched, but remember that the careenium is merely intended as a useful metaphor for understanding our brains, and the fact that our brains, too, are rather far-fetched, in the sense that they contain tiny events (neuron firings) and larger events (patterns of neuron firings), and the latter presumably somehow have representational qualities, allowing us to register and also to remember things that happen outside of our crania. .... The key idea is that whereas no simm on its own encodes anything or plays a symbolic role, the simmballs, on their far more macroscopic level, do encode and are symbolic. (pg. 46)

What DH seems to be proposing is that our sense of self, the "I" of consciousness, arises from the interplay between the microscopic neuronal firings and neurotransmitter work and the macroscopic, symbolic epiphenomena that we think of as awareness.

While the neuroscientists are happy to reduce all epiphenomena to the microscopic level (which is no doubt true in one sense), the complexity of such a system is infinitely complicated to the point of being incomprehensible.

No fixed portion of the universe [or mind] can be tightly fenced off from interacting with the rest -- not even approximately. To a reductionsist, the idea of carving the universe up into zones with inviolable macroscopic spatiotemporal boundary lines makes no sense. (pg. 47)

Same thing holds true in consciousness studies -- the more we learn about the brain, the more we know that there are no distinct cells that encode "love" -- there are auditory networks (songs, voices), visual networks (faces, flowers, books), olfactory networks (perfumes, pheromones), sensory networks (touch, arousal), and so on, almost infinitely, all of which encode the symbol/word "love".

Although he hasn't explicated the idea yet -- the next 60 or so pages explain the idea of feedback loops -- I think that DH is proposing that a feedback loop between the macro and the micro -- a strange loop -- is where we find the "I" of consciousness. This would provide the first workable "unified theory of consciousness."

I'll keep you posted.


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