Consciousness and the Brain: Deciphering How the Brain Codes Our Thoughts by Stanislas Dehaene
My rating: 5 of 5 stars
This is an excellent survey of that particular area of brain science at the forefront of which Dehaene is working. The bibliography alone is worth the purchase, and the narrative recognizes the work of a large group of direct colleagues, all of which provide some indication of how important his area is.
I was surprised to find Julian Jaynes referenced, which makes the second (after Dawkins) respectful nod I've seen from a respected source. He also pulls in Dennett and even Chalmers by the end, though Chalmers in a pretty dismissive way. I guess what I'm saying is that here is an exceedingly thoughtful and well-read scientist who had earned my solid confidence.
I do have to confess that his placing himself among those who ascribe to the 'brain in a vat' school of consciousness theorists puts me off. This also, obviously, means that he supposes that artificial consciousness is possible. While he takes pains to distinguish his model for consciousness from those which deploy computer metaphors, he still operates strictly within a fully empirical model, no spooks allowed.
No spooks allowed to my thinking either, but while I give him full high marks for his excellent science, I do believe that he operates within an obsolete paradigm. I say this mostly because he doesn't even consider emotion as a part of consciousness. I would guess that all the believers in 'brain in a vat' suppose that emotions are some low-order epiphenomena whose existence will drop out once the hard problems are resolved. And this hard stuff is really still mathematical and computational problems as presented here, metaphor or no.
In part, I'm buying the claim for a new paradigm staked out in another recent read: How Emotions Are Made: The Secret Life of the Brain, by Lisa Barrett (no mention in this book's bibliography). That book lays out a more constructivist view of reality, to be distinguished from the perceptually based theory of consciousness here. Everything about Dehaene's theory supposes a fixed and subject-independent external reality which correlates to whatever goes on in the brain.
Dehaene takes pains to distinguish those aspects of his experimental evidence which provide correlation without demonstrating causation or real findings. This is the bugaboo of all statistically-based investigation, which is most of science now. Long gone are the days of either/or billiard ball physics. All mechanism has now been replaced with either/or digital teasing out of a hidden reality (the reality beyond what we can perceive - the real real) which is so far from perception as to stretch credulity about the proof of a boson's existence, say, to almost the extent that social science might want you to see cultural relativity in the way that we construct most of our more mundane realities.
Lisa Barrett starts with how emotions are culturally grounded (not universal and inborn, as they have often been assumed to be) and constructed, like language is. Her bedrock is emotional concepts, which are also shared, often as a part of language, just as all reality is. I believe that Dehaene would agree about the language connection. He may even have been informed by Jaynes!
One way to distinguish emotional from perceptual "feeling" is that emotion is felt directly "in the mind" while perceptual feeling passes through the body, to be felt - perceived - at a distance. Indeed, one might suggest (I sure would) that most of the evidence described in this book - which relates to neuron-based brain activity as captured by varieties of instrumentation descended from fMRI and EEG - might reference more what is felt by the mind than is allowed here by its transmutation into 'readings' on the sort of instrument which stands-in for perception.
I am asking the question whether things which come to consciousness are ever emotion-free. Surely we must admit that most of what determines who we are - including our consciousness - is derived from a series of accidents more than it is derived from personal agency. Just try being born black (as has been related in ways that I fully trust).
Or in other words, much of what Dehaene defines as consciousness might be more emotive than empirically based. We can also read emotions by interpreting facial expression or heart-rate, but that doesn't mean that we've learned anything about what emotion essentially is.
To be fair, Dehaene is putting subjective reality fully front and center in his research. To be conscious is to be able to report what one is conscious of, which would include hallucinations, delusions, trompe-l'oeil, and more unreal stuff.
Dehaene provides a brilliantly comprehensive look at how most of the perceptual data which the brain receives is combined, conditioned, organized and conceptualized at the subliminal pre-conscious level. Consciousness is the coming into being of what feels to me like a kind of standing wave in a feedback loop. One of his great accomplishments is progress toward the detection of consciousness in a damaged brain, removed from bodily interaction from the world about.
Evidence for consciousness is made when all the subliminal unconscious Bayesian conjectures attempting to match what's actually "out there" with the raw perceptual data coming in finds a good match from memory 'within'. He describes the "ignition" of consciousness as happening when there is feedback from the conscious regions of the brain to where the subliminal stuff is happening. Contact!
There is a kind of match, or what I would call a kind of standing wave of resonance between subliminal constructs and what deserves or requires conscious awareness and attention. I would call it that because it might have the quality of emergence, like a snowflake, whose structure cannot be predicted from knowledge about its component parts, and their interactions. Emergent qualities put the lie to our current beliefs about causality, almost as though what emerges is a kind of primordial concept on the order of a Platonic idea. Or life itself, which is an emergent quality of matter.
In much the way that our eyes must constantly move about so that our brain can form a smooth reality in which we might navigate, this subliminal neural conjecture also jitters about on its own; not simply waiting for information to come in. Massive amounts of perceptual data turn into conscious awareness of some important 'thing' depending on our conscious attention and arousal. The subconscious mind already narrates - strings together in time - worthy candidates for conscious claiming. Consciousness is always slow to the game, taking credit for what the unconscious mind already put together from low-speed interconnections of disparate workings of the brain. Conceptualization is synchrony, where narrative builds across time. Aha!
Along with Lisa Barrett (I believe), I would call this coming to consciousness an emotive event. Like a lot of consciousness researchers, Dehaene looks for correlates in the brain for what is present to our conscious awareness. This sounds to me very much like what I would consider to be the mistaken notion that our brain contains a more or less complete "image" of the world around us. I would rather call these often so-called images what they really are, which is a collection of concepts.
One forms a concept of, say, a lion, by experience with several such creatures, likely preloaded with a name; a word from one's shared language. When confronted by an actual instance of the lion concept, and when that fills front and center of conscious awareness, we don't choose what to do about it based on conscious anything before being energized by the powerful feeling of fear.
Calling up what we think is a mental image of the lion might simply be reliving prior perceptions which are "stored" in our brain as delayed - endlessly looping - actual perceptions of actual things. This insight derives from the Spread Mind theory of Riccardo Manzotti (also not referenced in this book).
Manzotti comes from the field of artificial intelligence and not from neurology, and so is likely considered a flake from the perspective of serious brain scientists. Ironically enough, Manzotti seems to agree with me that there will be no such thing as artificial intelligence; at least not that would replicate human intelligence.
The big advantage of the Spread Mind theory as a basis to understand consciousness is that one doesn't have to decide whether objective reality is constructed. This is the same collapse that quantum physics realized, where subject can never be teased out entirely from object; where objects are a construct of probability until detected into reality. One is looking in the wrong place if one is looking for quantum features of the brain as a basis for "free will." They are already out there.
Intelligence is no more contained in and by a brain than a gene without its proper niche can describe a living host. By definition, the niche is as complex as the projected creature. Context and object, concept and percept, standing waves and particles, emotive and motive forces, conspire together for reality to emerge.
Artificial intelligence is not impossible because human intelligence is so very special. It's not. And I really doubt that human intelligence has gone very far toward what intelligence could be. Which is just another way to suggest that natural evolution isn't done yet. But what I am saying is that there would be and can be no intelligence at all without the whole of life on the planet. And I don't mean must life as it "led up" to us, but life as it is all around us. "Brain in a vat" is metaphor for intelligent life on an artificial planet or in virtual reality. Neither are possible.
(The living and conscious brain of a person who's lost their brain stem proves only the same thing that consciousness in a baby proves - neither is any way to live a full life)
Why is artificial intelligence not possible? you ask. Well, it is possible and it's all around us, but it will never be conscious.
OK, so here's my own little flaky contribution to the science of consciousness: emotion is not just in the mind, it's also out there, along with all that we perceive. Surely you might agree that lots of animals have emotions, but that's not the limit to what I mean. I mean that emotion is elemental in just the way that subatomic particles and forces are. We think the latter are what composes reality, but we know them directly only as our bodies interact with them.
Turns out that our interactions are determined by a hidden, non-perceptual reality which is only accessible by way of the conceptual gymnastics of a living mind in a living body which can handle the instrumental tools for discovery. These concepts are also shared, and not contained "inside" our minds. Gravity is the boundary between particle-mediated forces and the emotive prognostications of impingement among emergent beings. Both are equally real. Particles and concepts both pop in and out of nothingness. Reality is irony writ large.
Consciousness, even as it exists in a lizard or maybe a spider, allows us to navigate - to move - in the real world as it actually is, and even to make it more as we wish it to be, once we become human - a work still very much in progress. Our imagination helps with that. We are more intelligent in our interactions with reality, apparently, than is any other creature. That's especially so once language enters our picture and we can conspire together, as this book so powerfully demonstrates. Indeed the brain here is presented almost as a hierarchical ordering of a community of billions of otherwise independently clustering and firing neurons. It is presented as a metaphor for how society and civilization have accomplished so very much, so singularly as a social species. We are not conscious alone.
Navigating the world is, of course, directional in time and space. Our behaviors are based on the collective predictions of our neurons and our society. For physical reality, time is defined by entropy. The running out of a clock; the wearing of rocks in a river; the death of any individual life. Life moves the other way and has since the beginning of time.
In the beginning was the concept; a replicable structure for matter otherwise blowing apart. Atoms, molecules, structures, and the universal replicators of genetics. The anti-entropic direction for life - forward in time - is composed of the chance recombination of the raw stuff of physics into persistent conceptual structures. Their recombination in the direction of life makes a prognostication for the future. There are no physical forces which move us collectively that way. There is only emotive attraction and repulsion which no instrument will ever measure directly.
Emotion is what binds us to all of "creation." Emotion is what connects us to all that is alive. I mean this is the same technical sense that is meant when you call out a proton, please. I know we don't give a shit for the whales or the wolves, or even for each other based on the evidence. But that doesn't mean we're not connected. It does mean that to conceive of the cosmos as built of zeros and ones means to conceive of a cosmos in a vat, disconnected from anything else.
There is more to life than we can know by instrumental science. A mind confined to a brain - the brain in a vat, or the butterfly in the diving bell - is but a correlate to a mind and not the real thing.
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