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Pioneering Neuroscientist Wilder Penfield: Why Don't We Have Intellectual Seizures?
Evolution News and Views ^ | April 21, 2016 | Michael Egnor

Posted on 04/21/2016 12:30:08 PM PDT by Heartlander

Pioneering Neuroscientist Wilder Penfield: Why Don't We Have Intellectual Seizures?

Michael Egnor April 21, 2016 12:00 PM | Permalink

Wilder Penfield was a pivotal figure in modern neurosurgery. He was an American-born neurosurgeon at the Montreal Neurological Institute who pioneered surgery for epilepsy. He was an accomplished scientist as well as a clinical surgeon, and made seminal contributions to our knowledge of cortical physiology, brain mapping, and intraoperative study of seizures and brain function under local anesthesia with patients awake who could report experiences during brain stimulation.

His surgical specialty was the mapping of seizure foci in the brain of awake (locally anesthetized) patients, using the patient's experience and response to precise brain stimulation to locate and safely excise discrete regions of the cortex that were causing seizures. Penfield revolutionized neurosurgery (every day in the operating room I use instruments he designed) and he revolutionized our understanding of brain function and its relation to the mind

Penfield began his career as a materialist, convinced that the mind was wholly a product of the brain. He finished his career as an emphatic dualist.

During surgery, Penfield observed that patients had a variable but limited response to brain stimulation. Sometimes the stimulation would cause a seizure or evoke a sensation, a perception, movement of muscles, a memory, or even a vivid emotion. Yet Penfield noticed that brain stimulation never evoked abstract thought. He wrote:

There is no area of gray matter, as far as my experience goes, in which local epileptic discharge brings to pass what could be called "mindaction"... there is no valid evidence that either epileptic discharge or electrical stimulation can activate the mind... If one stops to consider it, this is an arresting fact. The record of consciousness can be set in motion, complicated though it is, by the electrode or by epileptic discharge. An illusion of interpretation can be produced in the same way. But none of the actions we attribute to the mind has been initiated by electrode stimulation or epileptic discharge. If there were a mechanism in the brain that could do what the mind does, one might expect that the mechanism would betray its presence in a convincing manner by some better evidence of epileptic or electrode activations.1 [Emphasis added.]

Penfield noted that intellectual function -- abstract thought -- could only be switched off by brain stimulation or a seizure, but it could never be switched on in like manner. The brain was necessary for abstract thought, normally, but it was not sufficient for it. Abstract thought was something other than merely a process of the brain.

Penfield's observations bring to light a perplexing aspect of epilepsy -- or at least an aspect of epilepsy that should be perplexing to materialists. Seizures always involve either complete unconsciousness or specific activation of a non-abstract neurological function -- flashes of light, smells, jerking of muscles, specific memories, strong emotions -- but seizures never evoke discrete abstract thought. This is odd, given that the bulk of brain tissue from which seizures arise is classified as association areas that are thought to sub-serve abstract thought. Why don't epilepsy patients have "calculus seizures" or "moral ethics" seizures, in which they involuntarily take second derivatives or contemplate mercy? The answer is obvious -- the brain does not generate abstract thought. The brain is normally necessary for abstract thought, but not sufficient for it.

Furthermore, Penfield noted that patients were always aware that the sensation, memory, etc., evoked by brain stimulation was done to them, but not by them. Penfield found that patients retained a "third person" perspective on mental events evoked by brain stimulation. There was always a "mind" that was independent of cortical stimulation:

The patient's mind, which is considering the situation in such an aloof and critical manner, can only be something quite apart from neuronal reflex action. It is noteworthy that two streams of consciousness are flowing, the one driven by input from the environment, the other by an electrode delivering sixty pulses per second to the cortex. The fact that there should be no confusion in the conscious state suggests that, although the content of consciousness depends in large measure on neuronal activity, awareness itself does not.2

Penfield finished his career as a passionate dualist. His materialist naiveté did not survive his actual scientific work and his experiences as a clinical neurosurgeon. My own experience as a neurosurgeon has led me to the same conclusion.

Remarkably, scholastic philosophers who worked in the Aristotelian tradition presaged Penfield's observations centuries ago. In the classical Aristotelian-Thomist understanding, the mind is several powers of the soul, which is the subsistent form of the body. "Subsistent" means that the soul informs the body, so to speak, as any form is composed to matter, but that it can exist independently of matter. The reason it can exist independently of matter is that the intellectual powers of the soul -- the ability to contemplate universals and engage in abstract thought -- is necessarily an immaterial power. Universals -- concepts that are not particular things -- by their nature cannot be in particular things, and thus cannot be in matter, even in brain matter.

Thus, the mind, as Penfield understood, can be influenced by matter, but is, in its abstract functions, not generated by matter.

Aristotle, if informed of Penfield's experiments, would have yawned: "Of course the mind is not wholly material. Abstract thought -- contemplation of universals -- is immaterial by its nature, and cannot be generated by the brain." The philosopher would have shrugged, as he concerned himself with other propositions that weren't as obvious. It is remarkable that insights from philosophers in the Aristotelian-Thomist school from millennia ago presage modern discoveries in the neuroscience of the mind-brain relationship with such stunning accuracy.

H/t: Chris Carter, Science and the Near-Death Experience: How Consciousness Survives Death.

References:

(1) Penfield, The Mystery of the Mind, pp. 77-8.

(2) Ibid., p. 55.



TOPICS: Health/Medicine; Science
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1 posted on 04/21/2016 12:30:08 PM PDT by Heartlander
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To: Heartlander

What, people don’t have those?

I feel like I have them all the time!


2 posted on 04/21/2016 12:35:25 PM PDT by rlmorel ("Irrational violence against muslims" is a myth, but "Irrational violence against non-muslims" isn't)
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To: rlmorel

Brain farts?


3 posted on 04/21/2016 12:37:46 PM PDT by shotgun
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To: Heartlander

Well, maybe it’s because abstract thoughts, and more generally the “mind”, aren’t the product of a single specific area of the brain. If abstract thought and consciousness are the product of an amalgamation of several areas of the brain working in concert, you’d have to have some kind of distributed seizure in order to provoke involuntary complex or abstract cogitation. On further consideration, involuntary abstract thought sounds a lot like having a dream. Is our sleep really just a massive, hours-long full-brain seizure?


4 posted on 04/21/2016 12:39:01 PM PDT by Little Pig
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To: Heartlander

Mind exists apart from the brain. Buddhism 101.


5 posted on 04/21/2016 12:43:19 PM PDT by TigersEye (This is the age of the death of reason and rule of law. Prepare!)
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To: Heartlander

Higher consciousness is an emergent property of a sufficiently complex neural network, not the function of any one mechanism.


6 posted on 04/21/2016 12:49:23 PM PDT by thoughtomator
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To: TigersEye
Mind exists apart from the brain. Buddhism 101.

The brain is just a collection of cells...just like the heart,lungs,liver,kidneys,etc.A chemical/physiological abnormality can cause profound alterations in thinking and perception.

7 posted on 04/21/2016 12:50:28 PM PDT by Gay State Conservative (Obamanomics:Trickle Up Poverty)
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To: Gay State Conservative
The brain is just a collection of cells...just like the heart,lungs,liver,kidneys,etc.A chemical/physiological abnormality in any of those organs can cause profound alterations in thinking and perception.
8 posted on 04/21/2016 12:52:06 PM PDT by TigersEye (This is the age of the death of reason and rule of law. Prepare!)
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To: Talisker

Ping to an extension of the brief conversation we had yesterday - my apologies, I had to break it off before it got to the interesting bits.


9 posted on 04/21/2016 12:54:00 PM PDT by Billthedrill
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To: shotgun

Lol, yes!


10 posted on 04/21/2016 12:58:20 PM PDT by rlmorel ("Irrational violence against muslims" is a myth, but "Irrational violence against non-muslims" isn't)
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To: Heartlander
Penfield began his career as a materialist, convinced that the mind was wholly a product of the brain. He finished his career as an emphatic dualist.

the falsity of materialism is why secular humanism with its denial of consciousness is a bad premise to base the foundation of libtardism on.

11 posted on 04/21/2016 1:00:50 PM PDT by mjp ((pro-{God, reality, reason, egoism, individualism, natural rights, limited government, capitalism}))
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To: Heartlander
Is he kidding me? I know of one guy who had been in intellectual status epilepticus for the last 7 years, minimum.


12 posted on 04/21/2016 1:07:06 PM PDT by Gamecock ( Do not be afraid of those who kill the body but cannot kill the soul...Matthew 10:28)
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To: rlmorel
Do you ever stop to think. . . .

and then have trouble getting started?

I do.

13 posted on 04/21/2016 1:10:12 PM PDT by BipolarBob (I'm so open minded that you should only think like me.)
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To: All

You are a spirit. You live in a body. The brain is the interface unit.


14 posted on 04/21/2016 1:10:29 PM PDT by TheTimeOfMan (Three Percenter - Cruz/West)
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To: Heartlander

to put it in computer terms ....his mapping of the brain told him that brain handled the io and handle the memory but it didn’t deal with the actual CPU function


15 posted on 04/21/2016 1:21:21 PM PDT by tophat9000 (King G(OP)eorge III has no idea why the Americans are in rebellion... teach him why)
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To: Heartlander

abstract thought could be just an aberration to begin with and makes no difference in the procreation of the species.


16 posted on 04/21/2016 1:24:56 PM PDT by HWGruene (REMEMBER THE ALAMO! Really, no kidding.)
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To: thoughtomator; Billthedrill
Higher consciousness is an emergent property of a sufficiently complex neural network, not the function of any one mechanism.

There are enough undefined terms in that sentence to make HAL start slamming doors on astronauts.

17 posted on 04/21/2016 1:53:24 PM PDT by Talisker (One who commands, must obey.)
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To: Talisker

Truth.

And yet, the statement still has meaningful semantic content.

Call it a metametaphor.


18 posted on 04/21/2016 2:07:36 PM PDT by thoughtomator
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To: thoughtomator

My problem with it is that through implication it suggests that consciousness is actually created by emergence. More properly, we can only say that a sufficiently complex system enables the emergence of measurable, or even detectable, consciousness. A rock, for example, could be fully conscious. But how would we know? It has no known mechanism to express that consciousness.


19 posted on 04/21/2016 2:13:35 PM PDT by Talisker (One who commands, must obey.)
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To: Talisker

The definition of consciousness is a slippery one, for sure. Maybe on some extremely rudimentary level, even a single atom has consciousness, or even its component parts.

Given simple physical instances of electrical charge like electrons and protons, atoms are composed which have properties no electron nor proton has. From where do these atomic-level properties come from? I would say they are emergent properties.

On a far larger scale we have simple neurons and to a large degree we do understand how they work as individual neurons. Get a bunch of these simple, understandable neurons together, however, and they are able to function in ways that we can’t even begin to understand.

Whether the properties of the configuration of individual parts are latent within those parts is not terribly important if the only way those properties can be expressed is through the configuration of a multitude of them. The exact mechanism need not be known to observe that collections of neurons can think while a single neuron may not, just as collections of fundamental particles can behave in ways a single particle may not. The recognition of emergent properties is something distinct from determining how exactly those properties emerge.


20 posted on 04/21/2016 2:32:36 PM PDT by thoughtomator
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