Over centuries, neuroscience folly repeats itself. Philosopher and mathematician René Descartes (1596–1650) broke from the classical (and quite satisfactory) traditional understanding of the soul. He proposed that the immaterial soul and the material body were separate substances, and he speculated that the soul and body meet in the pineal gland, a tiny gland in the center of the brain.

With the rise of mechanical philosophy and materialism in the 18th and 19th centuries, philosophers discarded Descartes’ immaterial soul. They replaced it with the concept of the mind, which was not necessarily immaterial. And then they concocted a jumble of crazy theories — behaviorism, identity theory, functionalism, and eliminative materialism — to square the circle. Somehow they had to account for the emergence of first-person experience from a wrinkly three-pound lump of meat. 

When modern neuroscientists discarded the soul, they labeled its replacement “consciousness.” They have since been picking through the brain for a 21st century version of the pineal gland, which, of course, never lived up to Descartes’ expectations. Thus, we hear: Consciousness comes from the cerebral cortex! No, it comes from the brainstem! No, it’s the thalamus! No, it’s the causal properties of the neurons!

Is the Brain an “Organic Machine”?

Neuroscientist Alan McComas thinks he’s finally solved the problem — consciousness comes from the hippocampi, which are two small clumps of neurons, one in each temporal lobe of the brain. He sees the brain as machine-like and thinks that the hippocampi are the conscious part of the machine.

McComas, enamored by machines, takes a reductionist approach (his words) in his recent article in American Scientist:

[The] reductionist approach…views consciousness as a function of the brain — a biological machine whose workings can be understood by an examination of its parts…[C]onsciousness requires no mystical explanation but rather is a function of the brain, an organic machine that we can understand through research.

But is the brain really an “organic machine,” as he says? “Organic” describes a body organ that has a natural set of powers — the heart pumps blood, the kidney makes urine, the stomach digests, etc. “Machine,” by contrast, means a non-natural thing — an artifact. It is assembled by intelligent agents (usually in a factory) for a purpose that is not natural to the materials of which the machine is made. Cars, wristwatches, and computers are machines, and they’re not natural at all. So the term “organic machine” is an oxymoron; if the brain is organic with natural powers, it can’t be a machine.

Perhaps McComas just means that “machine” is an analogy for the brain. The brain is like a machine. But what does that mean? He seems to mean that the brain, like a machine, has parts that work together to do things. But everything in the natural world has parts that work together to do things — atoms (made of electrons, protons, quarks, etc.), molecules, glaciers, trees, planets, galaxies, the whole shebang. So is everything a machine?

McComas could just as readily have compared the brain to a fire — it gives off heat. Or to a boat — it floats in cerebrospinal fluid. Or the brain is like a crumpled linen shirt, because it’s wrinkly. Analogies are useful if they give us useful insight into something. But to call the brain a machine because it has parts that work together to do things isn’t very helpful. Does anyone really think that brain doesn’t have parts that do things?  

Why the Claim that the Brain Is a Machine Matters

McComas’s “brain as organic machine” faux pas isn’t just harmless silliness. Physicist Werner Heisenberg (1901–1976) observed that “What we observe is not nature itself, but nature exposed to our method of questioning.” If McComas studies the brain as if it were a machine, he’ll conclude that it’s a machine, and his whole scientific perspective on the brain is yoked to his mistaken analogy.

Thus, when McComas searched this cerebral contraption for consciousness, he reported that he had found it! The CPU of consciousness is in “concept cells” in the hippocampi:

[H]ippocampal [concept cells]…respond to a certain person, place, or object while ignoring others. …[T]he image’s details [do] not seem to matter. Whether the person in the image was looking at the camera or away from it, dressed in different clothes, or sporting short or long hair, [makes] no difference. Remarkably, in some instances [concept cells] would still fire if, instead of an image, researchers substituted the written or spoken name signifying the person, object, or place…. Here [is] credible evidence of the role of hippocampi [and concept cells] not only in memory, but in the kind of holistic conceptualization associated with consciousness.

What Concept Cells Actually Do

Concept cells are indeed fascinating, but to attribute consciousness to them is nonsense. There are millions of people with damaged or destroyed hippocampi who are conscious. Bilateral hippocampal damage or loss is unfortunately common.

Alzheimer’s disease is characterized by hippocampal atrophy (decay). Hippocampi can also be destroyed by tumors, strokes, head injury, and the like. If concept cells nestled in the hippocampi were the seat of consciousness, bilateral hippocampal destruction would cause loss of consciousness. It doesn’t. Alzheimer’s patients are quite conscious; what they lack is memory. Similarly, bilateral hippocampal destruction by injury to the temporal lobes causes a catastrophic loss of ability to form new memories, but such patients are fully conscious.

Furthermore, there are disabled people who have hydranencephaly, a condition in which both cerebral hemispheres, which include the hippocampi, are destroyed by intrauterine strokes. People with hydranencephaly, although disabled, are quite conscious.

Concept cells and hippocampi are fascinating brain parts that clearly play a role in memory, but McComas’s theory that they are the seat of consciousness is nonsense. Which leaves us with the centuries-old question: What is consciousness, and where does it come from?

Where Does the Concept of Consciousness Come From?

The concept of consciousness is modern; the classical philosophers didn’t invoke it. What we call consciousness is akin to what the classical thinkers called perception — consciousness is the means by which we think and know, reason and will.

Because consciousness (or perception) is a means, and not an end, we can’t observe it directly or understand it as it is. It is somewhat like contact lenses. We see better when using them so we can think about what we see more clearly, but when we are using them, we don’t see them.Consciousness is also immaterial as well so it becomes a slippery concept…

If We Restored the Traditional Idea of the Soul

Classical philosophers were right about the invisibility of our means of perception and conception — that is why we have such difficulty studying and even defining consciousness. They generally followed the ancient philosopher Aristotle’s understanding of man: We have souls. The soul isn’t mystical — it’s just the set of abilities that make us alive. The composite of activities characteristic of life — breathing, metabolizing, reproducing, growing, moving, seeing, imagining, remembering, reasoning, willing — is the human soul. What neuroscientists like McComas call consciousness is just several of those powers of the soul.

Modern neuroscience has revealed much about the soul. The most remarkable thing we have learned from science about the soul is that it has two quite different and distinct sets of powers. On the one hand, we have physiological processes like control of heartbeat, breathing, hormones, as well as the ability to move our muscles, to perceive, to imagine, to remember, and to have emotions.

On the other hand, we have the capacity to think abstractly, to reason and to exercise free will.

The pioneering neuroscientists of the 20th and 21st centuries — Wilder Penfield, Roger Sperry, Justine Sergent, Yair Pinto, Benjamin Libet, and many others — have shown that the brain is the source of five of these kinds of activities—physiological control (of heartbeat, breathing, etc.), locomotion, perception, memory, and emotion.

But the higher human ability to think abstractly — to reason and will freely — are not physical abilities and do not come from the brain. Penfield showed that higher abstract thought could not be evoked from the brain by electrical stimulation. Sperry, Sergent, and Pinto showed that after split-brain surgery, patients have the ability to compare two images presented to different brain hemispheres even though no part of the brain could “see” both images. Libet showed that free will in making simple choices like deciding to push a button is real. Researchers in the emerging science of near death experiences have shown clearly that at least some of these experiences are real — that is, people can have awareness after complete cessation of brain function.

The Brain Is Not a Machine

Reductionism is nonsense, and “consciousness” is not nestled in clusters of neurons. Neuroscientists who search for consciousness in the brain cortex, the brainstem, the thalamus, or the hippocampi are engaged in something akin to pseudoscience. We have spiritual souls and physical bodies. Like the heart, the lungs, and the kidney, the brain is an organ by which we do things, like move, see, hear, remember, and emote. But we are spiritual creatures, created in our Creator’s image, and we have the immaterial capacity to reason and freely will.

Cross-posted at Mind Matters News.