Alva Noe, a professor of philosophy at UC Berkeley, has written a book called Out of Our Heads: Why You Are Not Your Brain, and Other Lessons from the Biology of Consciousness. Because of a number of interesting issues raised by Noe's book, I recommend reading it. But there are a number of serious problems with the way Noe defines consciousness.
When we talk about conscious, we're usually talking about subjectivity, awareness, a sense of the self (or self-reference), qualia and attention. For many people, including myself, there appear to be other qualities of consciousness as well. Among some additional qualities, I would include our sense of history, and the shock we sometimes feel when we can vividly recall incidents 20 to 50 years old. I would include our feeling for a nexus of relationships (but not the relationships themselves). I would also include the interiority of sensations that becomes obvious when we simply close our eyes or plug our ears.
Noe's book is a bit discursive but particularly in the first 20 pages. He writes the way I would imagine he talks on a discussion panel—intelligently but not always to the point.
He also protests too much about fMRI and PET studies. Maybe in the early years, researchers overstated what they had found but what I've been reading in the last few years suggests many neuroscientists are much more circumspect these days and not making the one-to-one correspondences they did in earlier years, particularly back when so many were guided by the modular thinking of cognitive psychology.
I would also add that some of the experiments now done are far more elegant than some of the experiments done back in the 1980s and early 90s. Furthermore, many older neuroscientists are feeling a little humility these days simply because there have been so many surprises. The brain is truly complex and we're a long ways from understanding it. Yes, there are some locked-in neurologists and locked-in philosophers who clearly aren't as open-minded as they should be about the study of the brain. It seems at times there are too many models out there about how the mind works based on too little information.
On page 22, Noe writes, "...it is highly likely that there is feedback. Neural activity in the brain during perception, for example, is not a one-way thing. Neural activity is characterized by loops and two-directionality." I agree with Noe here but I would say multi-directionality.
Neural feedback is an old concept that has had its ups and downs, more down in the 1980s perhaps when computer models of the brain and modular ideas of cognitive psychology were at their height. But neural feedback has always been an unavoidable and difficult part of understanding the brain. The late 60s neural feedback model had to be revamped over a number of years beyond the ascending/descending feedback systems to include the multiple routes involved; despite the difficulty of creating a vigorous model, we know from chaos theory that recursiveness has to be a key part of brain function. Noe actually picks up on this idea of recursiveness but his descriptions are often more about learning, language, life and experience rather than specifically about consciousness, though I should add that all these things contribute to consciousness without actually shedding light on what consciousness is. Language as an example can evoke the color red but it normally does not evoke the actual qualia of red which in any case is different than reading or hearing about the color red. Through training, one can shape or refine qualia. Musicians do this to varying degrees but a qualia of sound was there before the training.
Actually, getting back to what Noe said about neural activity, I think the feedback system of the brain is so crucial that the brain at times seems to have a pragmatic capacity to reset the button somewhat at key moments during the day and probably when we are asleep. The Orden and Papp paper, by the way, is from 1997 and seems dated in the context of Noe's book.
One of the big problems in Noe's book occurs early on when he in effect talks about the consciousness of bacteria. On page 41, he writes:
You can't both acknowledge the existence of the organism and at the same time view it as just a locus of processes or physicochemical mechanisms. And once you see the organism as a unity, as more than just a process, you are, in effect, recognizing its primitive agency, its possession of interests, needs, and point of view. That is, you are recognizing its at least incipient mindfulness.
The problem of consciousness, then , is none other than the problem of life. What we need to understand is how life emerges in the natural world.
Conciousness is not the same thing as life. Even if we concede that bacteria in some fashion has some tiny measure of consciousness, we also have to talk about levels of consciousness. To shift the frame slightly, the daisy has life but I'm not so sure it has consciousness—or what it means exactly if we say it does have consciousness. But Noe's comments raise an issue: it's odd that we're already in the 21st century and we still have difficulty defining life. The problem of fully defining life beyond such standard ideas as self-replication admittedly gives Noe wriggle room for his "Mind is Life" theme. But the distinction between consciousness and life remain a useful one.
I'm not at all buying Noe's idea that mind is life, largely because I think Noe's theme eventually undersells life and undersells consciousness. In the last twenty years, biology has gotten more interesting rather than less interesting. The fact that our genetic codes so thoroughly overlap across a wide range of seemingly unrelated species tells us immediately we have much more to learn. I agree with those biologists that point to the complex, dynamic wetness of life. Physics, chemistry and biochemistry still cannot explain life to us. Noe actually seems to respect much of this but I disagree with the heavy use of overlapping terms. And I would add there are also sobering observations out there about the nature, at least, of human consciousness. When people suffer damage to their visual cortex, they see themselves as blind and are not aware that they can in a real sense still see. Some aspect of consciousness has been lost and it not only is traced to the brain, it's traced specifically to neocortex. Not all animals have neocortex. But all animals and all plants are alive.
Whether he realizes it or not, Noe is tied to the hard determinism model of biological science. Or it might be better to say he is overawed by that model. I'm sure whatever is going on will eventually be explained by science but something is missing in our understanding of life and our understanding of consciousness. But Noe at least is trying to understand something that is beyond our conventional explanations. I appreciate how he talks about the organism interacting with the world and how tied that interaction is to fulfilling what the organism is. This is curiously consistent with fMRI research that has focused on what language and reading do to the human brain. Language and reading have a curious way of hooking up all the parts of our mind.
Again, I recommend Alva Noe's book but I wish he had called it something like, We Are More Than Just Our Brain.
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