Mind and Brain

From the Washington Post: The federal Centers for Disease Control and Prevention recently issued a flier to combat myths about the flu vaccine. It recited various commonly held views and labeled them either “true” or “false.” Among those identified as false were statements such as “The side effects are worse than the flu” and “Only older people need flu vaccine." When University of Michigan social psychologist Norbert Schwarz had volunteers read the CDC flier, however, he found that within 30 minutes, older people misremembered 28 percent of the false statements as true. Three days later, they remembered 40 percent of the myths as factual.The article suggests that when we hear or read a denial of a statement, we tend to remember the association of the items in the statement but not the fact that the statement was a negation. Thus nonsense tends to persist in the face of refutation. ...

A piece at the 700 Club describes Jeff Harshbarger’s childhood acquisition of a Ouija board, which he convinced himself was being used by demons to communicate with and ultimately possess him: Jeff: It scared me beyond anything I’d ever experienced but at the same time, it was like a rollercoaster ride. You’re scared to death but you’re thrilled. I began to recognize that there was a presence that began to develop in my house. I would wake up in the middle of the night and literally feel somebody’s watching me. I basically felt like someone was with me. I would wake up and walk through the house in order to experience that because I liked it.Of course, the movement of a Ouija board planchette is well-known to be caused by subconscious ideomotor movements by the people using it, as are similar phenomena like table-tipping. Table tipping was studied by the 19th century scientist Michael Faraday, who demonstrated that the forces applied to the table were coming from the people with their hands upon it. But Harshbarger convinced himself that he was accompanied by a presence that was controlling the planchette, and then that he was freed from demons by the intervention of a woman who led him to Jesus (and who he may have then married–the story’s not clear on that). (Via The Agitator.)

In an experiment by Friederike Range of the University of Vienna reported in the Washington Post, a border collie named Guinness would demonstrate to other dogs how to use her paw to push down on a bar to get a treat. Guinness would demonstrate in one of two different conditions–with a ball in her mouth, and without a ball in her mouth. Dogs prefer to use their mouths to move the bar, and so dogs that saw the demonstration while Guinness had a ball in her mouth inferred that she was only using her paw because her mouth was otherwise occupied, and would use their mouths. Dogs that saw her perform the demonstration without a ball would duplicate her demonstration, using their paws to push on the bar.

Via Will Wilkinson, the February 12, 2007 issue of The New Yorker has a nice profile of the Churchlands (PDF) which discusses their history and views on mind and brain (without once mentioning the term “eliminative materialism”): One afternoon recently, Paul says, he was home making dinner when Pat burst in the door, having come straight from a frustrating faculty meeting. “She said, ‘Paul, don’t speak to me, my serotonin levels have hit bottom, my brain is awash in glucocorticoids, my blood vessels are full of adrenaline, and if it weren’t for my endogenous opiates I’d have driven my car into a tree on the way home. My dopamine levels need lifting. Pour me a Chardonnay, and I’ll be down in a minute.’”Wilkinson points out that he has adopted similar use of scientific language about physical states to describe his mental states, and agrees with the Churchlands that this enhances the ability to describe what he’s feeling: I think that once one gets a subjective grasp of the difference between the effects of dopamine, serotonin, oxytocin, adrenaline, glucocorticoids, prolactin, testosterone, etc., monistic conceptions of pleasure and happiness become almost self-evidently false, and a kind of pluralism comes to seem almost inevitable as the trade-offs between different kinds of physical/qualitative states become apparent. Wilkinson’s blog post on the subject is here. I was also interested to see that the Churchlands are advocates of using the evidence from neuroscience in ethical and legal contexts, which brings to mind Jeffrey Rosen’s recent article in the New York Times (March 11, 2007) on “The Brain on the Stand." ...

Here’s a nifty little device that sits on your tongue and electrically stimulates it via 144 microelectrodes. Your brain figures out how to “see” patterns on the surface of this device, and: In testing, blind people found doorways, noticed people walking in front of them and caught balls. A version of the device, expected to be commercially marketed soon, has restored balance to those whose vestibular systems in the inner ear were destroyed by antibiotics.

Tom Gilson has posted some thoughts on the “self-undermining” arguments about rationality and naturalism that have been made by C.S. Lewis, Victor Reppert, J.R. Lucas, Richard Taylor, Alvin Plantinga, and others. The basic argument is that if our thoughts are the product of natural causes, then we have no reason to trust that the inferences we make are rational. There are many variations on the argument, and I think this basic line of argument goes back to ancient arguments about determinism. I offered my thoughts in the comments on Vic Reppert’s blog, and repeat them here: The conclusion that rationality is undermined doesn’t follow–at best the conclusion is that the connection between the physical causes and the rational inferences is at best a contingent one that is in need of explanation, which I think is a valid conclusion. But it’s one that is in the process of being answered as we learn about how the brain and perceptual systems work, how language develops, and how the mind evolved. If the fact that the brain operates in accordance with physical law undermined rationality, then the fact that computers operate in accordance with physical law would undermine their ability to perform logical inferences and computations. The real question is how brains came to be able to engage in rational inferences in virtue of the way that they physically operate, not whether they do. Gilson (and Victor) argue that they could only have this ability by being divinely designed to do so–a thesis that doesn’t seem to be particularly fruitful for scientific exploration.Naturalists and supernaturalists agree that we do engage in rational inferences. The supernaturalists think we do so using magical non-physical properties; many of them think that our minds are completely independent of our brains, though I think this is a position that is untenable in the face of empirical evidence from neuroscience (evidence which I have yet to see a substance dualist even attempt to address). In the face of arguments about the fact that computers are physical devices which engage in computation and inference, they respond that this is not real computation and inference, but only a derived computation and inference that is fully dependent upon human computation and inference. Naturalists, by contrast, think that our abilities to engage in rational inference and language have evolved, and that they are both dependent on natural causes and productive in generating additional natural causes of reasoning and action. They are far from perfect–we can identify systematic failures of reasoning that occur (e.g., examples of the sort in Kahneman & Tversky’s classic Judgment Under Uncertainty). And our understanding of our own abilities is far from complete–but is growing rapidly. Scientific examination of our cognitive capabilities has been extremely productive, while the supernatural thesis has been moribund. ...

I’ve posted a commentary on the exchange between Richard Carrier and Tom Wanchick about this particular argument from Carrier. The post is at the Secular Outpost.

Research by Jon-Kar Zubieta at the University of Michigan published in The Journal of Neuroscience shows that subjects told they were receiving pain medication produced more “opioid” activity in the brain, as measured by PET scans showing activation of “mu-opioid receptors.” Subjects given the placebo showed higher such receptor activation and reported greater pain relief, and had to be given higher levels of pain stimulus to maintain the same reported level of pain. So it’s not just mind over matter magic.

The Economist reports on research from Steven Most at Yale into a condition called “emotion-induced blindness” (apparently similar to and named analogously to motion-induced blindness). Most’s research shows that gory and erotic images trigger a condition which lasts for two-tenths to eight-tenths of a second during which the viewer fails to process what they see immediately afterwards. This is attributed to “an information-processing bottleneck in the brain when it is presented with important stimuli,” the categories in question being relevant to avoiding dangers and reproductive success, respectively. This phenomenon provides grounds for an argument that some content-based restrictions on visual material in certain locations (e.g., alongside highways) are justified on the basis of their potential to cause physical harm. (Or that liability should be incurred for resulting accidents by those who put such material in place.) ...