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April 27, 2016

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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.
Then Penfield is just wrong. Random example:

"In humans, transcranial direct current stimulation (tDCS) can be used to induce, depending on polarity, increases or decreases of cortical excitability by polarization of the underlying brain tissue. Cognitive enhancement as a result of tDCS has been reported. The purpose of this study was to test whether weak tDCS (current density, 57 microA/cm(2)) can be used to modify language processing. Fifteen healthy subjects performed a visual picture naming task before, during and after tDCS applied over the posterior perisylvian region (PPR), i.e. an area which includes Wernicke's area [BA 22]. Four different sessions were carried out: (1) anodal and (2) cathodal stimulation of left PPR and, for control, (3) anodal stimulation of the homologous region of the right hemisphere and (4) sham stimulation. We found that subjects responded significantly faster following anodal tDCS to the left PPR (p<0.01). No decreases in performance were detected. Our finding of a transient improvement in a language task following the application of tDCS together with previous studies which investigated the modulation of picture naming latency by transcranial magnetic stimulation (TMS) and repetitive TMS (rTMS) suggest that tDCS applied to the left PPR (including Wernicke's area [BA 22]) can be used to enhance language processing in healthy subjects."
http://www.ncbi.nlm.nih.gov/pubmed/17804023

Incidentally, I wouldn't trust Michael Egnor on anything - he is one of the most dishonest people that have ever plagued the www.

Andy, why attack the man? And, your rebuttal isn't a rebuttal at all, but a quote mine. You sound very angry, which casts doubt on your objection.

Cory, a "quote mine" is when you quote something while omitting relevant context - so that the quote appears to say something different than it would with the proper context. I didn't do that, none of the context in Egnor's post changes the meaning of the part I quoted in any way - and the part I quoted is simply flat out wrong as I demonstrated.

Andy, language processing isn't the same thing as abstract thought. And enhancement of something a person is consciously attempting to do (e.g., increasing its speed) isn't the same as stimulating the brain and causing the process itself to spontaneously occur (i.e., it's unlike causing someone to spontaneously experience a smell). Penfield's quotes in the original post explain more, and the last paragraph in the quote above is relevant, as well.

My artificial intelligence professor in college described his prevailing theory of the brain as hardware and the mind as software. His belief was that you couldn't tell what the mind was doing by studying neurons any more than you could tell that your computer was running Microsoft Word by measuring electrical current on your motherboard. Extending this analogy further, you could flip a bit on your computer's memory and notice that Word started to behave erratically or even crash, but nothing about flipping a single bit would cause a sentence to be written on the screen. I believe in dualism, but not for the reasons that Penfield cites -- I don't think they hold up.

Amy,

Andy, language processing isn't the same thing as abstract thought.

That is false. Language processing is one of the most intellectually demanding abstract thinking that humans engage in - if language processing does not count as abstract thought, nothing does.
To quote wikipedia:
"Thinking in abstractions is considered by anthropologists, archaeologists, and sociologists to be one of the key traits in modern human behaviour, which is believed to have developed between 50 000 and 100 000 years ago. Its development is likely to have been closely connected with the development of human language, which (whether spoken or written) appears to both involve and facilitate abstract thinking."

And enhancement of something a person is consciously attempting to do (e.g., increasing its speed) isn't the same as stimulating the brain and causing the process itself to spontaneously occur (i.e., it's unlike causing someone to spontaneously experience a smell).
If you induce a certain sense experience like a smell through an external stimulus, you do not cause a process to spontaneously occur, you rather alter a process that is already occuring and change the outcome. And it is no different with abstract thought. The person is already able to think in abstractions and already does so, the external stimulus alters how the brain processes that cause this thinking work. And it's not limited to enhancing abstract processes either (although that alone would already be incompatible with dualism). The brain can also be stimulated to completely change the way that abstract thoughts work - the most obvious example for that is LSD. And that change is not just detrimental - there are plenty cases of scientists, inventors and artists that had groundbreaking ideas while being high on cocaine or acid. This is not compatible with dualism, quite the opposite.

Andy,
If you don't believe in mind-body dualism, you are reduced to a machine that responds to stimulus (ultimately chemical/electric reactions in your brain in response to years of environmental and sensory input). You write what you write, think what you think and say what you say for the same predictable reason that an electric motor spins when electricity is passed through its wire. I do not argue with a motor about its direction of rotation or its speed. I don't expect the motor to respond to such discourse. Perhaps a discussion with you is equally useless. After all, if you change, all it means is that the input applied produced the necessary changes in the "neural network configuration" that is your brain and produced a different output.

kpolo,

If you don't believe in mind-body dualism, you are reduced to a machine that responds to stimulus (ultimately chemical/electric reactions in your brain in response to years of environmental and sensory input). You write what you write, think what you think and say what you say for the same predictable reason that an electric motor spins when electricity is passed through its wire.

An electric motor has neither conscience nor intentions - we do. And the truth of that is completely independent of whether monism or dualism wrt minds is correct. You might want to say that sentience like ours cannot possibly be reduced to or emerge from natural process in our brain, but unless you have an argument for that, this is just a mere assertion.

Perhaps a discussion with you is equally useless. After all, if you change, all it means is that the input applied produced the necessary changes in the "neural network configuration" that is your brain and produced a different output.
Do you have a point here? How exactly do you think it is relevant whether a person changing amounts to a) changes of brain states or b) changes of [insert your favorite hypothetical magical substrate of the human mind here]?

Related:

https://involutedgenealogies.wordpress.com/2016/04/28/a-brief-refutation-of-christian-physicalism/

A nice reminder of Physics' entire anthology affirming dualism :-)

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