Why splitting the brain doesn't split consciousness

Not too sure if this has been covered on here before but I'd noticed these recent articles on split brain patients from MindMatters explaining why splitting the brain doesn't split consciousness/the 'spirit'. I'm aware that they are somewhat biased, but their articles are still often well-supported and researched.

The first article discusses the work of Roger Perry brought up in an interview with Michael Egnor: https://mindmatters.ai/2020/04/if-your-b...ne-person/

So Sperry asked a question. He said, “What happens to these people?” It was clear that, by cutting the corpus callosum, their seizures were made better but were they still one person? What did cutting the brain, basically in half, do to a person? So he studied these patients in great detail...

...What Sperry did, though, was he studied them very, very carefully. And he found that there were subtle differences that—for example, it’s well known that, if you look straight ahead, everything to the left of the midline of where you’re looking is seen via the right hemisphere of your brain and everything to the right of where you’re looking is seen by the left hemisphere of your brain. So the visual fields kind of cross in the brain.

And Sperry showed that the left hemisphere is mainly the hemisphere that mediates speech and the right hemisphere tends to mediate geometrical and spatial understanding. If the corpus callosum is cut, the two hemisphere have perceptual abnormalities. If you sow the right hemisphere an apple, it’s capable of knowing that it is an apple but it is not capable of mediating speech in saying that it is an apple. Only the left hemisphere can do that. So he was able to understand the functioning of the hemispheres in a little more detail. But all of the functional abnormalities that he found, number one, they were undetectable in everyday life. In fact, that’s why he won the Nobel Prize. You don’t win the Nobel Prize for finding out obvious things. So in everyday life, these people were perfectly normal. On very careful, subtle testing, you could find these perceptual abnormalities...

But the other thing that he found was that all of these abnormalities were perceptual, none of them were intellectual… it wasn’t like you disconnected addition from subtraction or justice from mercy or integral calculus from differential calculus. There were no intellectual changes. These were all just perceptual...

...The implications of split-brain research have been widely debated. Scientists and philosophers have long argued over what is known as the mind-body quandary, the relationship between our mind and the physical brain. Some scientists saw the work of Sperry and others as supporting the notion that the brain operates almost entirely mechanically, and that consciousness, reasoning and free will have almost no effect. But Sperry strongly felt otherwise…

What this meant to Sperry was that free will, and responsibility, were no illusion. “It is possible to see today,” he believed, “an objective, explanatory model of brain function that neither contradicts nor degrades but rather affirms age-old humanist values, ideals, and meaning in human endeavor.”

I do think Egnor tends to jump to conclusions a little too often sometimes due to his biased beliefs, but he still makes some good points. I think he needs to be careful though when he starts making some claims that aren't concretely supported about the mind. Anyways, a more recent article basically pokes fun at an outdated video:
https://mindmatters.ai/2020/06/my-right-...t-no-wait/

The left hemisphere, for example, processes visual and tactile information from the right side of the visual field and body, and the right hemisphere processes visual and tactile information from the left side of the visual field and body. The left hemisphere (in most people) acts to produce speech, whereas the right hemisphere mediates many non-verbal tasks such as spatial orientation. Neither hemisphere “thinks” or “perceives,” any more than an eye sees or a foot walks.  A person thinks and perceives and sees and walks, using his brain and eyes and feet to do so. Neither organs nor parts of organs “think.”...

...Ramachandran goes on to quip about a series of questions he asked a patient via his right hemisphere (Are you on the moon? Are you in California?, etc.) and the answers he got from the patient (which were correct in those instances). He asked the patient his sex, which he misidentified, and then the patient laughed about it (the right hemisphere has a sense of humor!). Ramachandran doesn’t tell us if the patient used both sides of his mouth when he laughed. If so, his right hemisphere alone could not have mediated the reply (because the right side of the mouth is innervated only by the left hemisphere of the brain)...

He goes on to quote this research paper from 2017 (which happens to be the first thing that crops up on Google on the matter) that contradicted the claims made in the video: https://www.sciencedaily.com/releases/20...093823.htm

Another recent example was with the infamous Jerry Coyne: https://mindmatters.ai/2020/01/yes-split...you-think/

He claimed that:

“‘will’, ‘volition’ and ‘consciousness’ are the results of purely physical processes in the brain… perhaps the notion of consciousness and of will are things that merely report to us after the fact the deterministic actions of our brain, and are not in any way part of a causal chain.”

I'm not sure Coyne did any studies himself, since he apparently just 'formed his own conclusions' based on prior studies. I also have no idea whether he wrote a response to Egnor either

Coyne: “‘will’, ‘volition’ and ‘consciousness’ are the results of purely physical processes in the brain… perhaps the notion of consciousness and of will are things that merely report to us after the fact the deterministic actions of our brain, and are not in any way part of a causal chain.”

I think Egnor totally demolishes Coyne and other mind-body materialists in their arguments from the results of split-brain operations. 

And Coyne strikes me as remarkably incoherent in this statement in his blog. It's self-contradictory. What is a "notion" but a thought held in consciousness, which absolutely exists as something existentially different from "deterministic actions of the brain". Oh well, he probably doesn't even accept the existence of the Hard Problem.

Interesting stuff, I'd note there were reproducibility issues with the old split brain work as well.

In fact the interpretation of split-brain experiments has always been disputed. Although in experimental conditions the subjects seem divided, they don’t feel like two people and generally – not invariably -behave normally outside the lab. We do not have cases where the left hand and right hand write separate personal accounts, nor do these patients

Various people have offered interpretations which preserve the essential unity of consciousness, including Michael Tye and Charles E. Marks. One way of looking at it is to point out how unusual the experimental conditions are. Perhaps these conditions (and occasionally others that arise by chance) temporarily induce a bifurcation in an essentially united consciousness. Incidentally, so far as I know no-one has ever tried to repeat the experiments and get the same effects in people with an intact corpus callosum; maybe now and then it would work?

The philosopher Stephen Braude has made note of this as well, how oftentimes people will take results gleaned from artificial conditions in a lab and try to extend them as some discovered "law of psychology" as if such a thing could mirror the universal regularities we find in physics.

The thing that troubles me with Egnor is his association with the Discovery Institute, which has been heavily criticised for 'promoting pseudoscience'. I find it interesting how Wikipedia focuses more on bashing him than crediting his work, though I've noticed this bias has been apparently a thing for quite a while. Personally, I still appreciate his input since MindMatters is less likely to be biased, focusing less on ID, which I have mixed thoughts on myself. 

Meanwhile, Jerry Coyne's Wikipedia page seems to prefer to praise his work and gloss over the many criticisms levelled against him. You can mostly only find them under John Hogan's review of his book. I'm also pretty certain that Bernardo Kastrup had his own Wikipedia article but it has mysteriously vanished. Even if he didn't, the man definitely deserves one.

The thing that troubles me with Egnor is his association with the Discovery Institute, which has been heavily criticised for 'promoting pseudoscience'. I find it interesting how Wikipedia focuses more on bashing him than crediting his work, though I've noticed this bias has been apparently a thing for quite a while. Personally, I still appreciate his input since MindMatters is less likely to be biased, focusing less on ID, which I have mixed thoughts on myself. 

Meanwhile, Jerry Coyne's Wikipedia page seems to prefer to praise his work and gloss over the many criticisms levelled against him. You can mostly only find them under John Hogan's review of his book. I'm also pretty certain that Bernardo Kastrup had his own Wikipedia article but it has mysteriously vanished. Even if he didn't, the man definitely deserves one.

I think that you need to study the scientific basis of Intelligent Design theory, the overwhelming evidence for it, and the utter lack of evidence for Darwinism as the source of innovation in evolution. There is not only a lack of evidence for Darwinism as the source for most of evolution especially the major innovative leaps, but a pile of evidence clearly against it being any even remotely plausible mechanism. 

Of course the Darwinist mainstream of biology criticizes the Discovery Institute, both because it espouses and finances research into ID science, and because it is basically a Christian organization and opposes reductionist materialist naturalism. Of course the mainstream Darwinists (who are wedded to their ideology which is the most paradigmatically basic form of materialism) claim that because Discovery Institute is Christian it is promoting religiously-inspired "pseudoscience". Many in the mainstream continue to deliberately mistake the ID movement as fundamentalist Christian Creationism, which it most emphatically is not.

As I have pointed out before, the ultimate validity of an intellectual position on something in science or other subject matter has nothing to do with the religious orientation of the holder of that position, and has everything to do with the actual evidence for and logic leading to that position. An old false debating tactic.

I understand that nbtruthman, thank you. I think it is worth remembering that there are different 'forms' of Intelligent Design if I recall correctly, such as that at the quantum level, which I find more convincing personally. I do still respect Egnor however, especially since Wikipedia seems to gloss over his credentials. It doesn't even have an article on MindMatters or anything Egnor has said more recently!

The thing that troubles me with Egnor is his association with the Discovery Institute, which has been heavily criticised for 'promoting pseudoscience'. I find it interesting how Wikipedia focuses more on bashing him than crediting his work, though I've noticed this bias has been apparently a thing for quite a while. Personally, I still appreciate his input since MindMatters is less likely to be biased, focusing less on ID, which I have mixed thoughts on myself. 

Meanwhile, Jerry Coyne's Wikipedia page seems to prefer to praise his work and gloss over the many criticisms levelled against him. You can mostly only find them under John Hogan's review of his book. I'm also pretty certain that Bernardo Kastrup had his own Wikipedia article but it has mysteriously vanished. Even if he didn't, the man definitely deserves one.

It's worth adding a reminder that Wikipedia isn't a neutral resource. There may be references found there which themselves can be useful, but the commentary permitted in Wikipedia pages is inevitably biassed, pretty much by definition.

In terms of the topics we cover at Psience Quest, I'd suggest Wikipedia only as a possible starting point to help find some other resources, and not as a reference in itself.

So my minds been stuck on the split brain stuff again so I’ve formulated those thoughts to get them out of my head and hopefully add to the conversation.

The person from that 2017 paper actually has a more recent paper out where he and his team tested the somatosensory system of split brain patients. As a quick explanation, they generally replicated what they found in their previous study.
https://www.researchgate.net/publication...n_patients

Several of the same authors are also listed as authors on this paper talking about the current state of split brain studies and where to go moving forward.
https://www.researchgate.net/publication...sciousness

And cuz my mind likes to torment me, I’ve been thinking of a hypothetical: if it is found that the right side of the brain in split brain patients does exhibit a personality, wants and desires, etc., would that be some kind of blow to immaterial theories of consciousness? After thinking and reading on it, I don’t think it would.

I could certainly see issues with a dualist perspective (the idea of a single soul that should be indivisible) but I imagine it could still be argued that the relation to the brain causes weird effects to it in such cases.

An idealist metaphysics though, doesn’t seem to have this problem. With idealism having consciousness as the fundamental, it already presupposes some kind of separation and division so individual beings can exist. Donald Hoffman has talked about the split brain cases as an example of conscious agents creating more conscious agents. And Bernardo Kastrup has apparently mentioned in his book Why Materialism Is Baloney (at least according to a comment he made on his forum), in relation to his whirlpool metaphor, that a single whirlpool can be separated into two sub whirlpools with some careful intervention.

I also got introduced to a different perspective from listening to this episode of the Consciousness Podcast: https://theconsciousnesspodcast.com/epis...-niebauer/
The guest (who studies the left and right hemispheres) suggests that what the split brain experiments is really showing something about the mind and not consciousness. He also talks about how in the West people typically confuse consciousness for mind (basically thinking you are your thoughts as opposed to the one observing them). The guy seems to be more non dual which I don’t fully agree with, but I think he made a lot of great points.

And this isn’t even talking about the kind of evidence of stuff that’s discussed here. So yeah, these are my thoughts and hopefully some of you guys enjoy them.

And cuz my mind likes to torment me, I’ve been thinking of a hypothetical: if it is found that the right side of the brain in split brain patients does exhibit a personality, wants and desires, etc., would that be some kind of blow to immaterial theories of consciousness? After thinking and reading on it, I don’t think it would.

Those are interesting thoughts you had.

From my perspective, several things come to mind.

1. As far as I'm aware, split-brain patients/subjects continue to exhibit just a single personality.

2. Separate from this topic, there is of course the known phenomena of Dissociative identity disorder (DID), previously known as multiple personality disorder (MPD). This is not associated with split-brain as far as I'm aware. It is unrelated.

3. Colloquially speaking, the idea of left-brain versus right-brain has entered popular culture, supposedly one side is creative, another side rational and so on. Personally I take that with a pinch of salt. I tend to think the division in this case may not have anything to do with the split-brain at all, but may instead be illustrating a division between the material brain and the non-physical consciousness. But, it is not possible during our present-day establishment to express things in those terms, so instead the left-right language is used, since it is more politically correct.

Those are interesting thoughts you had.

From my perspective, several things come to mind.

1. As far as I'm aware, split-brain patients/subjects continue to exhibit just a single personality.

2. Separate from this topic, there is of course the known phenomena of Dissociative identity disorder (DID), previously known as multiple personality disorder (MPD). This is not associated with split-brain as far as I'm aware. It is unrelated.

3. Colloquially speaking, the idea of left-brain versus right-brain has entered popular culture, supposedly one side is creative, another side rational and so on. Personally I take that with a pinch of salt. I tend to think the division in this case may not have anything to do with the split-brain at all, but may instead be illustrating a division between the material brain and the non-physical consciousness. But, it is not possible during our present-day establishment to express things in those terms, so instead the left-right language is used, since it is more politically correct.

And of course there are the well documented (hydrocephalus) cases of people with hardly any brain, just a thin smear of tissue. 

 https://science.sciencemag.org/content/210/4475/1232