Tuesday, January 22, 2008

Defending Consciousness

The LA Times has an interesting editorial by Jonah Lehrer, called Misreading the Mind. The article is an impassioned defense of subjective experience -- what is often thought of as consciousness -- against the reductionism of mainstream neuroscience.

The success of modern neuroscience represents the triumph of a method: reductionism. The premise of reductionism is that the best way to solve a complex problem -- and the brain is the most complicated object in the known universe -- is to study its most basic parts. The mind, in other words, is just a particular trick of matter, reducible to the callous laws of physics.

But the reductionist method, although undeniably successful, has very real limitations. Not everything benefits from being broken down into tiny pieces. Look, for example, at a Beethoven symphony. If the music is reduced to wavelengths of vibrating air -- the simple sum of its physics -- we actually understand less about the music. The intangible beauty, the visceral emotion, the entire reason we listen in the first place -- all is lost when the sound is reduced into its most elemental details. In other words, reductionism can leave out a lot of reality.

This is a useful argument. In no way have we been able to "locate" consciousness in any of the nearly 100 billion brain cells residing in our skulls. Not have we been able to locate consciousness in any of the complex hierarchy of automatized skills and processes that function beneath our awareness. This is important, and I'll come back to it in a minute.

Lehrer continues:

If neuroscience is going to solve its grandest questions, such as the mystery of consciousness, it needs to adopt new methods that are able to construct complex representations of the mind that aren't built from the bottom up. Sometimes, the whole is best understood in terms of the whole. William James, as usual, realized this first. The eight chapters that begin his 1890 textbook, "The Principles of Psychology," describe the mind in the conventional third-person terms of the experimental psychologist. Everything changes, however, with Chapter 9. James starts this section, "The Stream of Thought," with a warning: "We now begin our study of the mind from within."

With that single sentence, James tried to shift the subject of psychology. He disavowed any scientific method that tried to dissect the mind into a set of elemental units, be it sensations or synapses. Modern science, however, didn't follow James' lead. In the years after his textbook was published, a "New Psychology" was born, and this rigorous science had no use for Jamesian vagueness. Measurement was now in vogue. Psychologists were busy trying to calculate all sorts of inane things, such as the time it takes for a single sensation to travel from your finger to your head. By quantifying our consciousness, they hoped to make the mind fit for science. Unfortunately, this meant that the mind was defined in very narrow terms. The study of experience was banished from the laboratory.

Again, a useful defense of the subjective element of consciousness that neuroscience so far has been unable to measure empirically. But it doesn't go anywhere toward solving the problem of consciousness -- who is this Self that I call and "I," that I can talk about, experience, or simply observe as it operates?

Merlin Donald, in A Mind So Rare, offers a possible solution, while not resorting to reductionism (which he names the Hardliner viewpoint) or some woo-woo ephemera that cannot be tested and therefore holds no value to science.

[T]he existence of of hugely complex hierarchies of automatized skills, such as languages, in the human mind does not constitute evidence that these skills reside in innate modules or that consciousness is out of the loop. Rather it testifies to the enormously important constructive role that consciousness plays in adult cognition. When we speak or see the world through the intervention of automatized subroutines, we are playing a cognitive instrument that was originally created and fine-tuned in consciousness and continues to be maintained by conscious processing.

This frees us from the conceptual prison of the Hardliners' philosophy. Inasmuch as awareness pilots the process of of cognitive development and continuously reviews, fine-tunes, and modifies the status of our automatized cognitive routines, there is a much greater degree of long-term conscious control over cognition than may be evident in the short-term perspective adopted by most experiments. Instead of locking into the immediate moment, conscious awareness has a lifelong constructive impact, through its guidance of the process of cognitive epigenesis. Moreover, as the concepts and ideas of a growing mind develop greater breadth, intermediate-term awareness gains enormously in power.

By ignoring these dimensions of conscious supervision, and by focusing exclusively on the low-end limits of sensorimotor performance, the Hardliners have distorted our view of consciousness.

....

In humans, particularly, consciousness is occupied more with intermediate-term governance, longer-term planning and supervision, and the process of self-assembly than with immediate sensation and reactive movement. It is a constructive device, ultimately responsible for assembling not only our representations of reality but the high-end cognitive system itself. (pgs. 58-59)

What he is arguing here is that much of the research in neuroscience -- that has resulted in the rejection of consciousness (the Hardliner, reductionist view) -- has been in the realm of short-term sensorimotor responses and short-term memory. The science tells us that these functions are largely automated -- as it should be. If we had to think about moving our hand out of the fire, we would suffer much worse burns. Likewise, if we had to think about each word we were about to speak (and some of us should), speech would take forever.

On the other hand, when we look at the intermediate-term functions of consciousness, we find that there is a there there -- meaning, we have cognitive control over many elements in our awareness, i.e., consciousness.

Yet, even this definition of consciousness doesn't address the ability of the anterior self to witness the activities of the proximate self and/or distal self, or of the proximate self to describe the distal self as "me" or "mine."

I suspect that Donald will get to this, but I have been slow in reading this book.


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