Hall of Mirrors

The Consciousness Conundrum Continues

To contemplate consciousness is, as professor of religion Greg Peterson put it, like looking into and out of a window at the same time.¹ Brain imaging was supposed to dissolve the hard problem of consciousness, but new information and insights have only deepened it.²

One quest has been to discover the seat of consciousness—the specific bit of the brain that spews out the unthinking electrical charges that create it. Seat? But wait, isn’t consciousness the table? You see the difficulty, of course . . .

It’s a long and winding road. 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.”³

The Discarded Triune Brain Theory

Surely, many have reasoned, our consciousness would reside in the most “human” parts of the brain. A popular theory of mind—the triune brain theory—attempted to meet this objective. Originally developed decades ago by Yale University physiologist and psychiatrist Paul D. MacLean (1913–2007) and promoted by celebrity skeptic Carl Sagan (1934–1996), it divides the brain into three parts.⁴ 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 birthed some immensely reassuring ideas for some. For example, pop science could depict a widely disliked boss or politician as a “dinosaur brain.” In 2021, Jeff Hawkins, inventor of the PalmPilot (a predecessor to the smartphone) even claimed to have figured out how human intelligence works by relying on his own interpretation of the mammalian brain.⁵

It turned out on further study, though, that key neurological functions are distributed throughout the brain. Also, triune brain theory doesn’t square with the mammal-like intelligence recently discovered to exist in invertebrate octopuses. Nor do claims for the mammalian brain square with the high intelligence found in some birds.⁶ And human consciousness, far from being leveled by all this theory and research, remains an absolute outlier.

But MacLean’s triune brain idea proved 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, and neuroscientists have urged psychologists to abandon the theory.”⁷

“I Am My Connectome”?

Never mind, the exciting new world of -omes (genomes, epigenomes, biomes . . . ) beckons. Could the connectome—essentially, a complete “wiring diagram” of the brain—identify human consciousness? In 2010, computational neuroscientist Sebastian Seung told humanity, “I am my connectome,”⁸ 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.’”⁹

That moment, too, passed. Harvard neuroscientist Jeff Lichtman, who is trying to map the brain, surveyed its awful complexity nearly a decade later and summed up the “Existential Crisis in Neuroscience”:

[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.”¹⁰

In short, once we are into the abstractions of the mind, we are no longer dealing with the concrete substance of the brain.

Consciousness as Bioelectric Fields?

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 argues, “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.”¹¹

This sounds cool but gets us nowhere. We could say the same about claims that everything is conscious, or conversely, that nothing is. We have no reason to believe that our individual brain cells are conscious; what we do know is that we, as whole human beings, are conscious. Whatever such fantastical claims may do, they shed no light on the consciousness conundrum at hand.

Perceptronium?

Max Tegmark, MIT physicist and author of Our Mathematical Universe (Knopf, 2014), goes more boldly than anyone. He suggests that consciousness is a so-far-undetected state of matter, perceptronium, “defined as the most general substance that feels subjectively self-aware.”¹² Which, again, sounds way cool but 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.”¹³ So while here, as elsewhere, it pays to be close to the source, this, too, brings us nowhere closer to understanding consciousness.

Meanwhile, Koch has also written a book, The Feeling of Life Itself (MIT Press, 2019), in which he offers many observations—on dogs, The Ring of the Nibelung, 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.”

Nonetheless, the roots remain elusive. In short, the neuroscience approach to understanding consciousness is back where it started, but we do have some interesting new books and big-idea words.

Notes
1. https://www.religion-online.org/article/god-on-the-brain-the-neurobiology-of-faith/.
2. https://consc.net/papers/facing.pdf.
3. https://today.duke.edu/2020/06/studies-brain-activity-aren%E2%80%99t-useful-scientists-thought.
4. https://www.realclearscience.com/articles/2023/06/03/what_carl_sagan_got_very_wrong_about_the_human_brain_903398.html.
5. https://www.technologyreview.com/2021/03/03/1020247/artificial-intelligence-brain-neuroscience-jeff-hawkins/.
6. https://www.lesswrong.com/posts/ixZLTmFfnKRbaStA5/book-review-a-thousand-brains-b.
7. https://journals.sagepub.com/doi/10.1177/0963721420917687.
8. https://www.ted.com/talks/sebastian_seung_i_am_my_connectome.
9. https://directorsblog.nih.gov/2012/11/05/the-symphony-inside-your-brain/.
10. https://nautil.us/an-existential-crisis-in-neuroscience-rp-237679/.
11. https://nautil.us/the-link-between-bioelectricity-and-consciousness-238148/.
12. https://www.pbs.org/wgbh/nova/article/physicists-say-consciousness-might-be-a-state-of-matter/.
13. https://www.nature.com/articles/s41562-020-0925-7?utm_c+target.