Consciousness, a Hall of Mirrors, Baffles Scientists
To contemplate consciousness is, as professor of religion Greg Peterson put it, like looking into and out of a window at the same time. No surprise then that philosophers of science call it the Hard Problem of Consciousness. The inexorable progress of brain imaging was supposed to dissolve the conundrum but we spoil no surprise by saying that new information and insights only deepened it.
Among the many quests, one has been to discover the seat of consciousness. An image rises unprompted. Seat? Does consciousness have a seat at the table? Wait a minute. Isn’t consciousness the table? You see the difficulty, of course. At any rate, the search is for the specific bit of the brain that spews out the unthinking electrical charges that create consciousness.
It’s been a long and winding road. Brain imaging has not turned out to be a road map of the mind. For example, functional MRI imaging only tells researchers where blood is traveling in the brain. The problem is, as a Duke University research group pointed out, “the level of activity for any given person probably won’t be the same twice, and a measure that changes every time it is collected cannot be applied to predict anyone’s future mental health or behavior.”
Rise and Fall of the Lizard Brain
The most widely popularized theory of mind — the triune brain theory — depends on organization rather than imaging. Originally developed by Yale University physiologist and psychiatrist Paul D. MacLean (1913–2007) decades ago and promoted by celebrity skeptic Carl Sagan (1934–1996), it divides the brain into three parts. The reptilian brain controls things like movement and breathing, the mammalian brain controls emotion, and the human cerebral cortex controls language and reasoning.
This approach resulted in immensely reassuring ideas; for example, a widely disliked boss or politician morphed into a “dinosaur brain.” In 2021, Jeff Hawkins, inventor of the PalmPilot (a smartphone predecessor) even claimed to have figured out how human intelligence works, relying on his model of the mammalian brain.
The human brain was bound to disappoint pop culture in this matter because key functions are distributed throughout. Also triune brain theory doesn’t square with the high animal intelligence recently found in (non-vertebrate) octopuses. Claims for the mammalian brain in particular don’t square with the high intelligence found in some birds. Let alone with the fact that human consciousness remains an absolute outlier.
But MacLean’s idea has proven much too culturally satisfying to be spoiled by mere neuroscience. As one research team notes, “despite the mismatch with current understandings of vertebrate neurobiology, MacLean’s ideas remain popular in psychology. (A citation analysis shows that neuroscientists cite MacLean’s empirical articles, whereas non-neuropsychologists cite MacLean’s triune-brain articles.)”
It’s All in the Connections
Never mind, the exciting new world of -omes (genomes, epigenomes, biomes…) beckons. The connectome — essentially, a complete “wiring diagram” of the brain, might possibly identify human consciousness. In 2010, computational neuroscientist Sebastian Seung told humanity, “I am my connectome,” a thought on which he expanded in his 2012 book, Connectome: How the Brain’s Wiring Makes Us Who We Are. In 2012, National Institutes of Health director Francis Collins was thinking along the same lines: “Ever wonder what is it that makes you, you? Depending on whom you ask, there are a lot of different answers, but these days some of the world’s top neuroscientists might say: ‘You are your connectome.’”
That moment has passed. Harvard neuroscientist Jeff Lichtman, who is trying to map the brain, surveys the awful complexity nearly a decade later and sums up,
…if I asked, “Do you understand New York City?” you would probably respond, “What do you mean?” There’s all this complexity. If you can’t understand New York City, it’s not because you can’t get access to the data. It’s just there’s so much going on at the same time. That’s what a human brain is. It’s millions of things happening simultaneously among different types of cells, neuromodulators, genetic components, things from the outside. There’s no point when you can suddenly say, “I now understand the brain,” just as you wouldn’t say, “I now get New York City.”
GRIGORI GUITCHOUNTS, “AN EXISTENTIAL CRISIS IN NEUROSCIENCE,” NAUTILUS, JANUARY 22, 2020
In short, once we are into abstractions, we are no longer dealing with the concrete substance of the brain.
It’s All in the Electricity
But what about the bioelectric fields that swarm throughout the brain? Bioelectric currents, unlike electric currents, rely on ions rather than electrons but they are still electricity. Evolutionary biologist and lawyer Tam Hunt tells us, “Nature seems to have figured out that electric fields, similar to the role they play in human-created machines, can power a wide array of processes essential to life. Perhaps even consciousness itself.” That’s a remarkable idea because it includes the notion that our individual cells exhibit consciousness: “Something like thinking, they argue, isn’t just something we do in our heads that requires brains. It’s a process even individual cells themselves, and not requiring any kind of brain, also take part in.”
This sounds cool but gets us nowhere. We have no reason to believe that our individual brain cells are conscious; what we know is that we are conscious as whole human beings. We could say the same about claims that everything is conscious (panpsychism) or that nothing is (eliminativism). Whatever else the claims do, they shed no light on the conundrum at hand.
Consciousness as an Undetected State of Matter
Max Tegmark, MIT physicist and author of Our Mathematical Universe: My Quest for the Ultimate Nature of Reality (Knopf, 2014), goes still further. He suggests that consciousness is a so far undetected state of matter, perceptronium, “defined as the most general substance that feels subjectively self-aware.” Which, again, gets us precisely nowhere.
Prominent neuroscientist Christof Koch notes more mundanely that physical distance in the brain matters: “A new study documents an ordering principle to these effects: the farther removed from sensory input or motor output structures, the less likely it is that a region contributes to consciousness.” And that’s about as far as neuroscience has got.
Koch has also written a book, The Feeling of Life Itself (MIT Press, 2019), where he tells us, among many other things, of dogs, Der Ring des Nibelungen, sentient machines, the loss of his belief in a personal God, and sadness, all seen as “signposts in the pursuit of his life’s work — to uncover the roots of consciousness.” And that is where we must leave the subject for now. We are back where we started — but we do have interesting books.
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