Are Consciousness and the Soul Found in Split Brain Experiments?
Written by: Matthew Sabatine
Image credits belong to: geralt | Pixabay
What is materialism? Materialism is the philosophy assuming that only matter is the core to all things in existence, and therefore assumes further that soul or spirit is not a core constituent of who we are and does not exist. All things, including mental states and consciousness, must be explained in terms of cells, molecules, atoms, and subatomic particles. Nothing more. Nothing less.
In a 2019 YouTube video, Dr. Michael Engor claims to refute materialism, leading us to think there is sufficient reason for denying the philosophy that denies the existence of souls and spirits.
Dr. Michael Engor is a neurosurgeon who works with children and is a professor of Stony Brook University’s neurology department. He has experience in performing a type of brain operation called a corpus callosotomy, in which he severs the fibers holding together the brain’s two hemispheres. This is an operation meant for alleviating the patient’s epileptic seizures. Mainstream materialists deplore him because of his rejection of evolutionary theory and support for Intelligent Design.
In the video I linked above, Engor discussed Roger Sperry who won the Nobel Prize for his 1960’s research on patients whose brains he bisected in the same kind of corpus callosotomy operations that Engor performs today.
In the 20th Century, neurosurgeons realized that a severance of the hemispheric fibers could block the travel of seizures from one hemisphere to the other, and therefore remedy the patient’s condition.
Engor states:
“Surprisingly, after the operation, the patients’ seizures would get better, of course, but they really were not much different. Their brains were essentially cut in half, but they still seemed to be a unitary person. They seemed to be fairly normal. Sperry was a neuroscientist who studied these people in detail. And he found that there were some abnormalities as a result of cutting the brain in half. But the abnormalities were very subtle. The differences were so subtle that the experiments won him the Nobel Prize. But they weren’t obvious. They weren’t obvious changes. What that implies is that the human mind is not purely generated by the matter of the brain. Otherwise, cutting the brain in half would have profound effects on the human mind. It might make two people. Certainly, it would create a profound difference in someone’s state of consciousness. And it doesn’t. You can cut the brain in half and the person can’t tell the difference, except that he has fewer seizures.”
I am unsure of Dr. Engor’s interpretation of Roger Sperry’s work. I am unsure that Sperry’s reports revealed a unity of consciousness after severance of the hemispheric nerve fibers.
I would like to provide you with some quotes from Sperry and my own interpretations of those quotes, to let you be the judge on Dr. Engor’s interpretations. I am open to any fair corrections for any mistakes I have made.
While reading a 1969 paper titled A Modified Concept of Consciousness written by Roger Sperry, what I have learned is that Sperry was dissenting against the popular view of his time, which argued that subjective happenings do not causally affect the course of events in the brain.
He states on page 533:
“It has long been the custom in brain research to dispense with consciousness as just an ‘inner aspect’ of the brain process, or as some kind of parallel passive ‘epiphenomenon’ or ‘paraphenomenon’ or other impotent by-product, or even to regard it as merely an artifact of semantics, a pseudoproblem.”
Alternatively, he endorsed the view that consciousness is an emergent property. I understand ‘emergent property’ in this context to mean that the constituents of our consciousness only become as such when they have a relationship or interaction as a whole. Individually, they cannot be identified as consciousness. Consciousness “exerts a directive holistic form of control over the flow pattern of cerebral excitation,” as Sperry states in the opening paragraph.
He appears to be suggesting that consciousness is split, as he states:
“In the surgically separated state, the two hemispheres appear to be independently and often simultaneously conscious, each quite oblivious of the mental experiences of the opposite hemisphere and also of the incompleteness of its own awareness. Many problems are raised in regard to the seeming unity of conscious experience in both the normal and bisected condition and the relation of conscious unity to the neural process.” (pg. 532)
Conscious experience is inextricably attached to the brain’s matter and limitations, even though the conscious properties of neuronal voltage are recognizably different from everything else. I interpret Sperry to say that the phenomenon of consciousness is best explained when we do not end our discussion with a fixation on molecules and physiology as individual units but also use them in ultimate reference to the whole or bigger picture. The brain cannot make the necessary series of actions to achieve its particular goal without reference to consciousness.
Sperry states:
“Just as the holistic properties of the organism have causal effects that determine the course and fate of its constituent cells and molecules, so in the same way, the conscious properties of cerebral activity are conceived to have analogous causal effects in brain function that control subset events in the flow pattern of neural excitation. In this holistic sense the present proposal may be said to place mind over matter, but not as any disembodied or supernatural agent.” (pg. 533)
The last sentence appears to lack endorsement of the supernatural even though I involved some teleology in my own interpretation.
Conscious forces may sculpt and fashion the streams and designs of excitation and neuronal voltage, but conscious properties are not interventionists. They are not breaching the physiological laws of nerve impulse traffic. There is no intervention but there is a supervenience, meaning that distinctive attributes of one thing are visible and present because of the distinctive attributes of another. One cannot exist without the other. Let me use a sculpture as a comparison:
A sculpture’s contours, outlines, degree of compactness, consistency of surface, and matter are the essential, inseparable attributes that exist alongside the combination of qualities that are pleasing to the senses. If you could find another public display of beauty that is essentially identical to the sculpture–a matching twin–could that second display still aesthetically differ from the sculpture? If the answer is ‘no’ then the aesthetics would supervene on what is intrinsically present. A set of properties, F, supervenes on a set of properties, G, which entails that any differences in F-properties calls for a difference in G-properties. A brain and all of its electricity, wiring patterns, neuronal firings, synaptic transmissions, ionic flows, and glial supports cannot exist separately from the overall scheme of consciousness.
Sperry states further:
“This comes about as a result of higher level cerebral interactions that involve integration between large processes and whole patterns of activity. In the dynamics of these higher level interactions, the more molar conscious properties are seen to supersede the more elemental physiochemical forces, just as the properties of the molecule supersede nuclear forces in chemical interactions.” (pg. 534)
These quotes are reflected in Sperry’s book titled Science and Moral Priority–Merging Mind, Brain, and Human Values. In that book, he inveighs against “the pervasive influence of creeping materialism.” However, he also admits that “once we have materialism squared off against mentalism in this way, I think we must all agree that neither is going to win the match on the basis of direct, factual evidence. The facts simply do not go far enough to provide the answer, or even to come close.” The “physiological language of the cerebral hemispheres” was not sufficiently understood for accomplishing the task during his time. Brain code is constructed upon patterns of space-time and excitations involving ionic flow in and out of the cell.
But…
“When it comes to even imagining the critical variables in these patterns that correlate with the variables that we know in inner conscious experience, we are still hopelessly lost.” (pg. 30)
The people of his time had an acceptable understanding of the translations of messages happening within the brain. But they were clueless as to how the messages are incoming and from where they were originating:
“The central unknowns directly associated with consciousness seem to be rather well cushioned on both the input and output sides of the brain by further zones of physiological unknowns. Our explanatory picture for brain function is reasonably satisfactory for the sensory input pathways and the distal portion of the motor outflow. But that great in-between realm, starting at the stage where the incoming excitatory messages first reach the cortical surface of the brain, still today is very aptly referred to as the ‘mysterious black box.’” (pg. 30)
There is an intuitive and speculative basis, instead of an empirical basis, behind the assumption that the mind and consciousness are not in the driver’s seat and not manipulating the physical and chemical processes. For Sperry, mind is over matter, and “not under or outside or beside it.” Ideas are effectively above the trafficking of neurons and DNA.
For Sperry, there is a rank of biological authority and organization that inhabits us in regard to “who pushes whom around.” The energetic subnuclear forces of causality are numerous but…
“do not have very much to say about what goes on in the affairs of the brain. We can pretty well forget them, because they are all firmly trapped and kept in line by their atomic overseers. The atomic nuclei and associated electrons are also, of course, firmly controlled in turn. The various atomic and subatomic elements are ‘molecule-bound”--that is, they are hauled and pushed around by the larger spatial and configurational forces of their encompassing molecules.” (pg. 32-33)
For Sperry, the “forces of perception, emotion, reason, belief, insight, judgment, and cognition” all are in a chain of command that sit atop the primitive cellular, molecular, and atomic workings of nerve impulse. Ideas sit at the peak of the mountain overlooking everything. Man is higher than animals because he possesses ideas and ideals that feel just as concrete and real as a molecule, cell, or nerve impulse. Ideas respond to and advance from other ideas. Not individual molecules. Not individual cells. And not individual nerve impulses. Ideas affect each other in the same brain, affect the ideas of other brains, and grab megaphones and talking screens and advertising campaigns to spread themselves to brains in distant countries.
Sperry speaks of a “higher command”:
“Even the brain cells, however, with their long fibers and impulse-conducting properties, do not have very much to say about when they are going to fire their messages, for example, or in what time pattern they will fire them. The firing orders for the day come from a higher command.”
“Higher command” is an interesting choice of terms, as if to suggest that something other than the sodium channels, cell membranes, action potentials, and neurons is causally connected to the firing. I suppose that materialists and reductionists would object to the apparent anthropomorphism of “higher command” and say that I should avoid teleology.
But this is where materialism and reductionism becomes fuzzy for me. This is where language about physical stuff reaches its boundary, and we cross over the threshold into language about non-physical stuff. The non-physical stuff is ‘ideas.’ If ideas are somewhat synonymous with thoughts, perhaps thoughts are the “higher command”? Maybe thoughts must superimpose on neurons. Maybe thoughts also precede neurons. What a crazy idea! But how else can we bridge that gap between the material and immaterial? This parallels with Sharon Dirckx, a woman with a PhD in brain imaging, who said that “there is nothing in any study that will get you to the conclusion that neurons create thoughts.”
Perhaps Sperry’s 1980’s word choice of “higher command” was alluding to something for which we have a better understanding, today. Perhaps the “higher command” involves a cell reaching its threshold prior to firing information and electrical signals down the axon. Perhaps the “higher command” involves the actions of the sodium channel and the changes of cell polarization, initiating the action potential moving along the axon.
Perhaps he was alluding to the all-or-none law which states that action potentials either occur or they do not. To explain that law further, the robustness of a stimulus does not determine the robustness of a nerve cell’s response or a muscle fiber’s response. The response is either fully there or fully not. There is no in-between. For me, that argues against a deterministic universe that tells me I am essentially defined by the laws of biophysics with no core soul or spirit connected to a consciousness or a mind beyond me. Is it obvious what I think that implies for me as a Christian? If my thoughts sit at the top of the chain of higher command, and if God is interwoven with many of my thoughts, then thoughts of God persuade me to think He is my ultimate commander.
Here is another idea to propose for another blog post: Can my thoughts influence the timing and firing of action potentials down my axons? Can my thoughts determine whether a stimulus is above or below the threshold for firing a nerve or muscle fiber? Furthermore, how can I be used to influence myself? What forces of my external environment should I allow to influence me, to determine the next stimulus that will go above or below the necessary threshold for firing an action potential? Well, it is impossible for me to zoom into my own inner micro-worlds to observe every firing happening within every second. So, perhaps I really cannot know.
Sperry states that the entire cerebral circuitry commands the stream and schedule of impulse traffic. The collective properties of the cerebral system may make far-reaching changes within itself on a moment-to-moment basis because of one flip of a micro-switch in some small corner we overlooked. Such micro-changes that involve significant micro-consequences can be related to something that feels so insignificant, such as “a shift of attention, a turn of thought, a change of feeling, or a new insight.”
Thus Sperry ends with an eye-opening statement:
“To make a long story short, if one keeps climbing upward in the chain of command within the brain, one finds at the very top those overall organizational forces and dynamic properties of the large patterns of cerebral excitation that are correlated with mental states or psychic activity. And this brings us close to the main issue.” (pg. 33)
Two different brains do not have the same “specialized cerebral circuitry.” They are wired differently. Therefore they cannot exactly feel nor exactly know each other’s subjective qualities without being inside each other or married to each other. This means that each individual has an inner life that can only be known by himself/herself and no one else. Sperry’s severances of the brain hemispheres belonging to cats and monkeys involve a few “cross-connections” between the two, making two minds that acquire knowledge, awareness, and sensory perceptions that are separate from each other. However, some visual and tactile subjective experiences can still be shared between the two hemispheres if some “cross-connections” are left unbroken.
Sperry states that this can be replicated in humans who get a corpus callosotomy with unbroken “cross-connections” between parts responsible for emotion and feeling. The two severed brain halves share emotional experiences but un-share the experiences of sight, hearing, memory, and knowledge acquisition.
“For example, if an emotion is triggered through vision by the introduction of an unexpected pinup picture of a nude into a sequence of ordinary geometric pattern stimuli being projected into only the right lobe, it is quite apparent from the verbal readout through the other half of the brain (that is, the one not directly excited) that this second hemisphere also feels properly embarrassed–or whatever the case may be. The second hemisphere, however, has no idea why it has these inner feelings and is unable to describe their source.” (pg. 37)
Based on these quotations from Sperry’s 20th Century writings, perhaps Engor’s statements about unity of consciousness are in reference to the cross-connections and shared emotional experiences between the two severed hemispheres. Perhaps they are overstatements, unfortunately.
However, Engor is a neurosurgeon. I am not.
He must be seeing something in his patients that I could never see.
Considering Sperry’s rejection of materialism, and espousal of mentalism, in light of his research on the split minds of his patients, I believe the materialists have gained no victory points from this. As a Christian, I remain unconvinced that God does not exist.
General Disclaimer: All sources are hyperlinked in this article. The author has made their best attempt to accurately interpret the sources used and preserve the source-author’s original argument while avoiding plagiarism. Should you discover any errors to that end, please email thecommoncaveat@gmail.com and we will review your request.
All information in this article is intended for educational/entertainment purposes only. This information should not be used as medical/therapeutic advice. Please seek a doctor/therapist for health advice.
Sources:
[1] Michael Egnor: The Evidence against Materialism - Science Uprising Expert Interviews - YouTube
[2] A modified concept of consciousness (typeset.io)
[3] Supervenience and Mind | Internet Encyclopedia of Philosophy (utm.edu)
[5] Iain McGilchrist & Sharon Dirckx • Brain science, consciousness & God - YouTube
[6] Action Potential and How Neurons Fire (verywellmind.com)
[7] All-or-None Law for Nerves and Muscles (verywellmind.com)