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Thursday, May 08, 2008

Placebo effect: Your mind's role in your health

Recently, a group of writers from The Word Guild got together and contributed essays to a book, Hot Apple Cider. I offered an essay that looked at some of the findings from The Spiritual Brain - what I learned about how mental states affect physical health. Here's part of my reflection, for your enjoyment:

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You probably aren’t waiting for science to come up with “the perfect pill for every ill,” but if you know anyone who is, he or she likely will be waiting a long time. Not because dramatic science discoveries will fail, but because the effect of many medical treatments depends at least in part on the patient’s expectation. Doctors know this by experience, of course, but research has shed new light on how powerful the patient’s expectation is.

In 2004, University of Michigan researchers reported on a study of pain experienced by healthy young male volunteers. To induce pain, they injected saltwater into their volunteers’ jaws and measured the impact by positron emission tomography (PET). They then gave the volunteers a substance described as pain relief. Not only did the volunteers report feeling better thereafter, but a number of brain regions that activate when we experience pain showed a reduced response. In other words, there was external evidence that the volunteers’ subjective belief that they felt better corresponded to the reality of pain signals in their brains.

However, … and this is the key point … no pain relief drug had actually been used in the study! The volunteers felt less pain simply because they believed they had received a powerful drug. The researchers commented that their study demonstrates how our perceptions truly affect the amount of pain we experience. This study, along with many others, showed that the effect of what we believe is real and measurable in scientific terms.

This effect is usually called the placebo effect, after a Latin phrase meaning “I will please.” Some researchers prefer to call it the “meaning effect” or the “remembered wellness” effect. Whatever its name, the meaning you attach to a treatment helps determine how effective that treatment will be for you.

For example, anthropologist Daniel Moerman of the University of Michigan notes that various studies have shown that large pills work better than medium-sized pills and four pills work better than two, even when all the pills are sugar and all the injection are sterile water. And culture can make a difference in the relief we experience too. North Americans tend to believe that injections are more powerful than pills, so injections of sterile water may provide us more relief than a sugar pill (even though both are placebos). But that does not work for Europeans who do not think that injections are more powerful than pills. Blue sleeping pills work better than other colors—except when given to male Italian soccer fans whose team colour is blue.

Even sham surgery works. Sylvester Colligan of Beaumont, Texas, could barely walk before his 1994 knee operation. He was mobile and free of pain six years later. But, as he later learned, he was actually in the control group. Yes, he received three knee incisions, but he was just sewn up again afterward; no conventional arthroscopy was done. But his body did not know that because his mind did not.

Similarly, a 2004 study compared 30 patients who received controversial embryonic stem-cell implants for Parkinson’s disease to patients who received only sham surgery. The patients who thought they had received the stem cells reported better quality of life a year later than those who thought they had received the sham surgery—regardless of which surgery patients had actually received. Ratings by medical personnel tended to concur with the patients’ own views. That last point is significant. The more your doctor believes in a treatment, the more likely you are to experience relief from it.

At one time, doctors suspected that more emotionally expressive people responded more strongly than stolid souls, but that does not seem to be the case. Our minds are real, and what we expect to happen is important.

Still, there are limitations on the power of our minds. Placebos do not help to treat cancer (though they help cancer patients with appetite and pain control). Also, only a person who is intellectually capable of believing that a medication provides relief can experience the effect of hope. One study found that Alzheimer patients whose cognitive deficits interfered with their ability to expect relief did not experience it.

Still, looking at the big picture, the effect—call it “placebo” or “meaning” or whatever you like—is pretty powerful. All drugs are tested against it—not because it doesn’t work but precisely because it does. A medication must work five percent better than a placebo to be licensed for use. That makes sense. You certainly would not want to pay $159.95 for a prescription that worked only one percent better than faith that you will get well. The money would be much better spent on a day at the spa.

So... throw out the medications? By no means! They already have been tested and found to be more useful than placebos, or they would not be on the pharmacist’s shelf. But, as Moerman says, the power of expected healing shows that meaning—our interpretation of what is happening to us—can make a huge difference to how effectively medications work. He sums it up: “Meaning can make your immune system work better and it can make your aspirin work better too.” Whether medications are intended to help us with physical or psychological problems, we must actively cooperate with them to make them work their best for us.

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Philosophy of Mind: In case you wondered whether you are conscious and reading this ...

This preprint is an academic argument (I think) for the actual existence of consciousness (as opposed to the materialist view that consciousness is merely an illusion) that you do not want to try at a party this Saturday night:
Is Consciousness primary?

Abstract:
Six arguments against the view that conscious experience derives from a material basis are reviewed. These arguments arise from epistemology, phenomenology, neuropsychology, and philosophy of quantum mechanics. It turns out that any attempt at proving that conscious experience is ontologically secondary to material objects both fails and brings out its methodological and existential primacy. No alternative metaphysical view is espoused (not even a variety of Spinoza's attractive double-aspect theory). Instead, an alternative stance, inspired from F. Varela's neurophenomenology is advocated. This unfamiliar stance involves (i) a complete redefinition of the boundary between unquestioned assumptions and relevant questions ; (ii) a descent towards the common ground of the statements of phenomenology and objective natural science : a practice motivated by the quest of an expanding circle of intersubjective agreement. (By Michel Bitbol (2008))

Actually, there is hardly a materialist explanation for consciousness that is even worth discussing, as Mario and I point out in The Spiritual Brain, because the phenomenon is non-material in principle.

For instance, as John Searle, among others, has said,
“The most striking feature is how much of mainstream [materialistic] philosophy of mind is obviously false….[I]n the philosophy of mind, obvious facts about the mental, such as that we all really do have subjective conscious mental states…are routinely denied by many…of the advanced thinkers in the subject.”

-- John Searle, The Rediscovery of Mind (Cambridge, MA: MIT Press, 1992), 3.

Well, those who cannot account for something deny it.

Some recent Mindful Hack stories on consciousness:

Mind vs. meat vs. computers: The differences

Consciousness: Recent public squabble between philosophers of mind rates better than most sitcoms

Interview with Spiritual Brain authors Mario and Denyse at campus Web site

Books: New physics takes on the human mind

Is consciousness a trick to ensure survival?

The Spiritual Brain reviewed in Jesuit thinkmag America

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Animal minds: Learning may not pay, but some animals do it anyway

In "Lots of Animals Learn, but Smarter Isn't Better" (May 6, 2008), New York Times science writer Carl Zimmer tackles the question of how learning evolves.

If your science prof told you long ago that learning evolves because animals that learn faster are more likely to survive, forget it. Learning imposes costs of its own, as one experiment showed:
Dr. Kawecki and his colleagues pitted smart fly larvae against a different strain of flies, mixing the insects and giving them a meager supply of yeast to see who would survive. The scientists then ran the same experiment, but with the ordinary relatives of the smart flies competing against the new strain. About half the smart flies survived; 80 percent of the ordinary flies did.

Reversing the experiment showed that being smart does not ensure survival. “We took some population of flies and kept them over 30 generations on really poor food so they adapted so they could develop better on it,” Dr. Kawecki said. “And then we asked what happened to the learning ability. It went down.”

The ability to learn does not just harm the flies in their youth, though. In a paper to be published in the journal Evolution, Dr. Kawecki and his colleagues report that their fast-learning flies live on average 15 percent shorter lives than flies that had not experienced selection on the quinine-spiked jelly. Flies that have undergone selection for long life were up to 40 percent worse at learning than ordinary flies.

Actually, most life forms have not relied on high levels of individual learning to survive (or not, as the case may be). Quick learning is, after all, an alternative to built-in behaviour. Whether it is better or worse depends on the circumstances, I suppose.

The article closes with speculations about human learning. But I don't think the comparison to fly and worm learning really works.

The reality is that we humans must learn. If we don't, we suffer, just as we would if we didn't exercise. Friends who nurse people with Alzheimer and other dementias say that the best defense against the disease is to keep on learning. One Alzheimer nurse recommends learning a new language, for example.

A healthy neuron is a busy neuron? I would love to see a neuroscience study on that!

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Heard way, way too often: The soul boils down to a few genes?

Materialism, as I learned while working on The Spiritual Brain, is exceedingly difficult to parody effectively. Materialists put me out of work by parodying themselves.

Take for example, this gem of a puff by reviewer Michael A. Goldman for the latest molecular biologist Lee Silver's latest book, Challenging Nature, in Science (the AAAS's publication). Silver, a molecular biologist, believes that his field is "compared with every other field of scholarship and science the least compatible with spiritual beliefs." GOldman goes on to say,
Many scientists are afraid to ask what differentiates humans from all other animal species. The Christian view is still heavily influenced by the idea that the human spirit remains beyond scientific inquiry. In Silver's view, the major emphasis of human genome analyses in the Western world has been to enhance health, but some investigators (including researchers at the RIKEN Institute in Japan) have been asking how we differ genetically from chimpanzees. Silver thinks that one day the difference will boil down to a few dozen genes, a kind of "soul code." Of his host at RIKEN Silver writes, "Sakai yearns to answer a question possibly as old as humankind itself: What gives a human being a human mind with the ability to ask the question 'What gives a human being a human mind?'" These investigators were "trying to find the DNA code for the human soul." When Silver asked the researchers at RIKEN whether or not they might one day try to transfer those very genes into a nonhuman primate, their answer was affirmative: they would, if they could, try to imbue a chimp with a human soul. The Neandertal genome projects may provide even more exciting information for the next edition of Silver's book.

If Silver really thinks that the difference between humans and chimpanzees will boil down to a few dozen genes or a kind of "soul code", I think that the incompatibility is not between spirituality and molecular biology but between spirituality and Silver.

Interestingly, Goldman admits that he didn't read Silver's earlier Remaking Eden because
I found the author's bravado in interviews as an unabashed salesperson for our biotechnological future distasteful and embarrassing. I almost dropped a popular textbook just for adding him as a co-author. I still cringe a bit after reading Challenging Nature, but now I think it isn't so bad to have an eloquent, well-traveled, and well-read counterbalance for Leon Kass and Jeremy Rifkin. It is refreshing to see Silver's careful, though biased, examination of the issues from a scientific perspective on bioethics. The Princeton professor's new book provides insight into and ammunition against almost any anti-biotechnology argument scientists are likely to encounter.

It sounds suspiciously like Goldman is willing to put up with any nonsense Silver offers as long as he thinks that spirituality boils down to a few dozen genes or a soul code. Or, as the free summary* of Challenging Nature at Science puts it, "Proclaiming an unlimited promise for biotechnology, the author paints its varied critics as uniformly ignorant and blinded by spiritual beliefs" - which means he is on the side of the lumps of flesh, I guess (a good thing, apparently).

There, you see, if I had just said that on my own initiative, you might criticize me for misrepresenting materialism, implying that it is more foolish than it is. But I didn't say it, I only reported it.

The culturally significant fact is that so few in legacy media take issue with or critique any of this stuff. But then, that's why they are legacy media, right?

By the way, have a look at the next post down, Materialist Mythbusting: Genes 'R' Not Us, if you think genes tell us everything. (For one thing - and this is only one thing among many - with genes, as with music, it is the expression that counts, not the notes written down somewhere.)

Here's Silver's book:


*Note: Michael A. Goldman's review of Challenging Nature at Science (Oct. 20, 2006: Vol. 314. no. 5798, p. 423) is hidden behind a subscribewall, and you need to scroll down at the Biotechnology Knowledge Center link provided above.

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Materialist Mythbusting: Genes 'R' NOT Us

"Score one for the nurture side of the nature vs. nurture debate, " says the ambitious press release from the North Carolina State University, following some of their researchers' discovery that
By studying gene expression of white blood cells in 46 Moroccan Amazighs, or Berbers – including desert nomads, mountain agrarians and coastal urban dwellers – the NC State researchers and collaborators in Morocco and the United States showed that up to one-third of genes are differentially expressed due to where and how the Moroccan Amazighs live.
The research team, which looked at the 23,000 human coding genes of members of three Amazigh groups, discovered that whether people followed urban, rural, or nomadic lifestyles significantly influenced which genes were expressed, even though members of the group had very few genetic differences. For example,
... they found respiratory genes were upregulated, or turned on, more frequently in the urban population than in the nomadic or agrarian populations. This makes sense, Idaghdour says, as urban dwellers deal with greater amounts of pollution in the city and encounter more difficulties with diseases like asthma and bronchitis. So it stands to reason that certain respiratory genes in city dwellers go into overdrive while staying quiet in rural and nomadic populations, he adds.
Anyone remember the 1997 film GATTACA? Produced in the looming shadow of the mapping of the human genome (2000), it captures the basic idea behind genetic determinism - Genes 'R' Us - and then subverts it.

In the words of David A. Kirby of Science Fiction studies at DePauw University in Indiana,

GATTACA depicts a future world in which parents are encouraged to decide the genetic makeup of their offspring before birth. In this world not everyone has access to the technology, and individuals who have not been genetically enhanced encounter severe discrimination. GATTACA’s narrative focuses on Vincent Freeman, a genetically unenhanced individual, and his interactions with three characters, Eugene, Irene, and Anton, who are genetically enhanced. During the course of the film, Vincent avoids genetic discrimination by passing off Eugene Morrow’s genetic makeup as his own. Because everyone believes that Vincent has Eugene’s genetic profile, he is able to obtain a job at the prestigious Gattaca corporation, which arranges offworld expeditions. ... Early in the film an executive is murdered at Gattaca, and the subsequent investigation is conducted by Vincent’s genetically augmented younger brother, Anton. A stray eyelash provides DNA evidence, making Vincent the prime suspect in the murder.
But GATTACA assumes that determination to succeed is the only thing that eventually enables Freeman to overcome his handicap ("There is no gene for the human spirit"). The handicap itself is viewed as fixed and irrevocable. In a scene near the movie's opening, a health technician informs Freeman's parents that, among other things, he will die in his late twenties, due to a heart defect. There it is, his whole fate, just like a sum drawn correctly on a chalkboard ...

That conventional view of the future of genetics has been widely disseminated in popular media, but recent research, like this North Carolina State study, has dealt some serious blows. As the study illustrates, genes must be expressed in order to be effective, and environment and lifestyle play a role in how they are expressed. Determination to succeed plays a key role in humans, to be sure, but the "Freemen" of the world will doubtless be glad to discover that they have other heavy hitters on their team as well.

Abstract, citation, paper, and other resources

Abstract: The different environments that humans experience are likely to impact physiology and disease susceptibility. In order to estimate the magnitude of the impact of environment on transcript abundance, we examined gene expression in peripheral blood leukocyte samples from 46 desert nomadic, mountain agrarian and coastal urban Moroccan Amazigh individuals. Despite great expression heterogeneity in humans, as much as one third of the leukocyte transcriptome was found to be associated with differences among regions. Genome-wide polymorphism analysis indicates that genetic differentiation in the total sample is limited and is unlikely to explain the expression divergence. Methylation profiling of 1,505 CpG sites suggests limited contribution of methylation to the observed differences in gene expression. Genetic network analysis further implies that specific aspects of immune function are strongly affected by regional factors and may influence susceptibility to respiratory and inflammatory disease. Our results show a strong genome-wide gene expression signature of regional population differences that pesumably include lifestyle, geography, and biotic factors, implying that these can play at least as great a role as genetic divergence in modulating gene expression variation in humans.

Citation: "A Genomewide Gene Expression Signature of Environmental Geography in Leukocytes of Moroccan Amazighs" by Youssef Idaghdour and Greg Gibson, North Carolina State University; John D. Storey, Princeton University; and Sami J. Jadallah, HRH Prince Sultan International Foundation for Conservation and Development of Wildlife, Agadir, Morocco was published April 11, 2008, in PloS Genetics.

The paper is here.

Other resources:

North Carolina State News Release



Note: Materialist myths about human origins and existence - like Genes 'R' Us - are busted weekly at Design of Life blog.

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