Updates are in italics. Note that the first part of this is very much lifted from the piece I referenced. Hopefully that was clear when it was first published, but if not, my apologies to the author (Colin Klein) for that.
Your brain represents only 2% of your body weight. However, it is estimated that it consumes 20% of more of your body’s energy, even at rest. Modern Brain imaging techniques like fMRI or PET scans purport to associate particular states of consciousness with increased activity in specific areas of the brain. In the most basic of terms increased “activity” as measured by fMRI or PET or other techniques correlates with increased “activity” in a particular state of consciousness. So so far so good. It certainly makes cognitive sense to connect the two. It turns out that one of the founders of modern brain imaging techniques, Robert G. Shulman has begun to question this supposed link. In a fascinating new (not so new anymore) work he suggests and describes in detail the weaknesses of this approach to cognitive neuroscience and modern neurophilosophy. It turns out that many imaging studies actually show a decrease in brain activity related to rest as measured by modern technologies in response to a given cognitive task. Modern interpretations of this data suggest that the decrease is attributable to increases in activity in areas related to self reflection and social reasoning. In other words it’s not really a decrease at all but simply an increase in other non-related areas of the brain. Shulman argues that every area of the brain is active at rest not just the specific areas attributed by modern researchers. I can tell you for a fact my brain is never at rest and boy does it suck sometimes.
So far I have relied (and cribbed) extensively from Colin Klein’s excellent review of Shulman’s book. I highly recommend you read it if you are at all interested in this area of research/philosophy/neuroscience. http://ndpr.nd.edu/news/40439-brain-imaging-what-it-can-and-cannot-tell-us-about-consciousness/
However at this point I will diverge from Klein’s viewpoint and offer an alternative interpretation. Klein suggests that Shulman is endorsing a stand often dubbed “pragmatic philosophy”. He goes on to ascribe this view to the perhaps the twentieth centuries greatest philosopher’s of mind Ludwig Wittgenstein. In turn he impugns the works of Bennet and Hacker who provided one of the strongest and most controversial (debatable/debated might have been better word choices) supports of Wittgenstein’s views to modern neurophilosophy. Basically “pragmatic philosophy” as described by Klein says that concepts described by the sciences are useful and thus should be adopted while those used in cognitive neuroscience/philosophy are useless and should be discarded. I certainly have sympathy for this approach but disagree that Wittgenstein and even Bennet/Hacker (WBH) would go quite this far. (I should have been a bit stronger here and said they would not even go close to this far) It is not so much that cognitive terms should be discarded but rather that they should be questioned and doubted and treated with a higher level of skepticism than scientific terms that have been “proven” with empirical data. Summing up the hypothetical position of two of the modern giants of neurophilosophy or any philosophy in one or two sentences is a near impossible and always dangerous task. I am sure if they read this they would expound at length on how I have mischaracterized their views. Oh well, they surely never will so hah!
To illustrate my point I now introduce the work of Julian Jaynes. Undoubtedly his seminal work on the bicameral mind is (of the) non-scientific/pragmatic (variety). He presents arguments that have the veneer of science but on deeper probing rely, for the most part, on conjecture and theory. In my opinion his thoughts/theories/hypothesis on the structure and function of consciousness are some of the least “pragmatic” of the twentieth century. Yet, I have little doubt that Wittgenstein and Bennet/Hacker would embrace his views. Not because they are so “unscientific” but in spite of this fact. True genius as the sort practiced by Wittgenstein and to a lesser extent Bennet/Hacker recognizes its own. Even if/when that genius clashes with closely held beliefs. Now that is a whopper of a supposition on my part. One can have little doubt about something and still be 100% wrong. It happens to me a lot. As I and others have said many times, conviction in belief and correctness of belief often have an inverse relationship.
I suspect that Jaynes would support Shulman’s argument that functional brain imaging is a poor (at best) representation of the working of the conscious mind. I am not exactly sure that is true. I sure wish he were around to ask. Moreover I would argue that WBH would mostly agree. Even the laymen is exposed to news stories on a regular basis suggesting that such and such brain area has been associated with so and so activity/cognitive state. Almost always these stories are reported based on studies conducted with brain imaging techniques. More often than not these results are presented as fact. I would argue that WBH and Janes would dispute these so-called facts as at least partially artifacts of the techniques being employed to generate them. In reality the “facts” of brain imaging are at best half truths. Suggestive of something but not necessarily descriptive of the question at issue. Until we have a better understanding of the brain at so called “rest” we will never be able to truly ascribe functional imaging results to cognitive states. More simply put our brain baseline needs a better definition before deviations from it can mean anything real. I left out of this one of the bigger problems with these studies and that is the cross category/vagueness problem whereby often times the cognitive attribute being studied is something like “criminality”, a term with a huge number of possible definitions and characteristics that cross a number of categories of human thought/belief/behavior.