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At Mind Matters News: The brain stem, not the prefrontal cortex, may be the seat of consciousness


In a recent discussion/debate with neurosurgeon Michael Egnor, neuropsychologist Mark Solms offers an unconventional but evidence-based view, favoring the brain stem:

In September, neurosurgeon Michael Egnor debated atheist broadcaster Matt Dillahunty at Theology Unleashed, on the existence of God. This time out (October 22, 2021), he is teamed with distinguished South African neuropsychologist Mark Solms, author of The Hidden Spring (2021) — who begins by declaring, in his opening statement, “the source of consciousness in the brain is in fact in the brain stem,” not the cerebral cortex, as almost universally assumed. He explains his reasoning with evidence.

Egnor doesn’t dispute that statement; in fact, in his own opening statement later, he reinforces it with observations from his own practice.

News, “Consciousness: Is it in the cerebral cortex — or the brain stem?” at Mind Matters News

Mark Solms: I have been led to the view, over a few decades of working in this field, that we’ve made a big mistake in our conception of consciousness in neuroscience. The mistake has a very long history, which I won’t go into, but it boils down to the view that the seat of consciousness in the brain is the cerebral cortex. This is an absolutely universal view with a very few… few exceptions, myself included, obviously.[00:03:30]

It’s our evolutionary pride and joy. But … a lot of evidence, suggests that the source of consciousness in the brain is in fact in the brain stem, which is a much more ancient, much more primitive structure that we share, not only with all other primates and all other mammals, but in fact, with all vertebrates. The basic structure of the brain stem in you and me is the same as it is in fishes. If you’re going to look at it from the physical point of view, which part of the brain, is bound up with this mental property that we call consciousness? It is the reticular activating system, in particular, of the brain stem. It’s primitive core. I said, there’s tons of evidence, but let me just mention the most dramatic bit of evidence. [00:05:00]

A very old fashioned method in neuroscience is the lesion method. Lesion is just a fancy word for damage. So, if there’s damage to a part of the brain that performs a certain function, then that function should be lost. If you apply the lesion method to this question, you find that if you damage just a tiny area of the reticular core of the brain stem, roughly two cubic millimeters in extent, in other words, the size of a match head, then the lights go out. Consciousness is lost entirely. On the other hand, there are children who are born with absolutely no cerebral cortex, a condition called hydranencephaly, and these kids are conscious. They’re conscious in the sense that they wake up in the morning, and they go to sleep at night, but more interestingly, they are emotionally responsive to their environments. [00:06:00] … More.

Takehome: The evidence shows, says Mark Solms, author of The Hidden Spring, that the brain stem, not the cerebral cortex is the source of consciousness.

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These findings concerning the brain stem being the ultimate source of at least primitive consciousness will undoubtedly be used by materialist neuroscientists to claim that NDEs originate from the brain stem. They will claim that NDEs occuring "while the brain is dysfunctional" are really not - they come from the brainstem which is still supposedly active even when the frontal lobes are moribund during cardiac arrest and other traumatic circumstances. They will also claim this to explain the cases of normal or near-normal intelligence in hydrocephaly and other patients with no or almost no frontal lobes at all. Of course this sort of argument will be invalid, because materialist neuroscience has to assume that full consciousness (and NDEs are often of enhanced super-clear consciousness) is the function of or is identical with the incredibly complex data processing of untold millions and billions of neurons in the brain. But the brain stem (especially what has been found to be the matchhead-sized core of consciousness) is a small structure with nowhere near the huge data processing capacity that is assumed to be able to generate consciousness. The function of this core structure in the brain stem is most likely the central interface between immaterial consciousness and the brain, allowing consciousness to manifest in the physical via the physical brain. So it doesn't look that these research findings will constitute any sort of "out" for the scientism believers. doubter
Nope, it has to be more basic than that. Cephalopods are unquestionably conscious because they have dreams. Their brains are entirely different. The simplest hypothesis is that consciousness is a universal property of LIFE. polistra

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