The Physiology of Placebos Magnetic Underlays Superstition Survey (Part 2)
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The physiology of placebos Magnetic underlays Superstition survey (Part 2) number 91 - autumn 2009 content editorial The physiology of the placebo effect 3 The supernatural Magnetic underlays: what’s the attraction? 3 retains its appeal Newsfront 10 Forum 12 LTHOUGH formal religion is continuing to decline in this Hokum Locum 14 Acountry, belief in the supernatural remains high. That seems Supersitious? Me? That to be the main conclusion to be drawn from a recent survey of New depends (Part 2) 18 Zealand religious affiliations and attitudes carried out by Massey University as part of the International Social Survey Programme. Evolution: What the fossils say and why it matters – The survey of 1000 people found 40 percent of respondents said Book Review 19 they had no religious affiliation compared with 29 percent just 17 years ago. Fifty-three percent said they believed in God, although half of those said they had doubts, and 20 percent believed in some form of higher power. Professor Philip Gendall, who led the study, said there had been no change in the proportion of those who say they believe in a higher power. “The survey shows that God is not dead, but religion may be dying,” he said. Fifty-seven percent believed in life after death, with 51 percent believing in heaven and 36 percent ISSN - 1172-062X believing in hell, the survey showed. Contributions Of particular interest to skeptics were the responses on supersti- Contributions are welcome and tions, though these were only a small part of the overall study. A should be sent to: quarter thought star signs could affect people’s futures, 28 percent David Riddell said good luck charms work and 39 percent said they believed for- 122 Woodlands Rd tune-tellers could foresee the future. RD1 Hamilton Email: [email protected] Perhaps we can take some comfort in the fact that those figures are all well under 50 percent, but they’re still high. It would be interest- Deadline for next issue: ing to see reliable, up-to-date figures for attitudes in New Zealand June 10 2009 towards alternative medicine, creationism, mediums, UFOs, and the Letters for the Forum may be edited various claims of the alternative archaeology crowd. Some of those as space requires - up to 250 words I suspect would be really alarming. is preferred. Please indicate the publication and date of all clippings I’m not aware of any formal attempt to carry out such a study. The for the Newsfront. closest would be last year’s Sunday Star-Times survey, of which the second half of Vicki Hyde’s response is printed in this issue. Re- Material supplied by email or IBM- compatible disk is appreciated. spondents in that were a self-selected subset of the paper’s readership – hardly a random sample of the entire country. All the same, where Permission is given to other non- comparisons could be made, results are fairly comparable with the profit skeptical organisations to Massey survey – eg 40 percent of respondents said they believed in reprint material from this publication provided the author and NZ Skeptic God with another 10 percent not sure, which could be rephrased as are acknowledged. 50 percent believing but 10 percent uncertain, quite similar to the Massey figures. About 44 percent thought it was possible to foresee Opinions expressed in the New Zealand Skeptic are those of the the future, which is again close to what Gendall’s team found. So individual authors and do not even though the Sunday Star-Times survey’s prime objectives were to necessarily represent the views of entertain and to sell papers, it seems it may NZ Skeptics (Inc.) or its officers. have provided a useful snapshot of New Subscription details are available Zealanders’ attitudes to the paranormal. from www.skeptics.org.nz or PO Box 29-492, Christchurch. number 91 - autumn 2009 main feature The physiology of the placebo effect Martin Wallace Placebos may contain no active ingredients, but they have real effects on the human brain. This arti- cle is based on a presentation to the NZ Skeptics 2008 conference in Hamilton, September 26-28. ARLIER this year, Dr Tipu response to some arcane practice seventh to ninth centuries. Chau- EAamir of the Auckland Pain is a placebo response, that settles cer called one of his characters Management Service drew my at- the issue. Placebo in the Merchant’s Tale, tention to something peculiar. In because the word had come to a double-blind, randomised, pla- Over the last 30 years there has mean a flatterer, a sycophant, or cebo-controlled trial of morphine been a large amount of research a parasite, by the 14th century. after a standard knee operation, into the undoubted effects of “Placebo seyde: 30 percent of those receiving a placebos. I thought it might be Ful little need had ye, my lord placebo get pain relief. When of interest to review this work in the context of our frequent use so deare, those people are given a specific Council to ask, of any that are morphine antagonist (‘antidote’), of ‘placebo effect’ to explain the unscientific. here their pain comes back! In the But that ye be so ful of sapi- words of a former contributor at ence.” an annual conference of this society, this was an epiphany. He also uses it in the Par- I needed to know more. son’s tale: “Flatterers be the Devil’s chaplains, which sing After all, how could some- ever ‘Placebo’.” thing that was ‘all in the mind’ be changed predictably In the 1811 edition of by a substance with a known Hooper’s Medical Diction- pharmacological action? ary, placebo was defined as “an epithet for any medicine Any study of homeopathy adopted more to please than raises the issue of the pla- benefit the patient”. In a re- cebo effect. As a result of a cent edition of Collins’ Con- meta-analysis in 2005 of a cise Dictionary of the English number of studies comparing Language it is defined as “an homeopathic remedies with inactive substance adminis- What does ‘all in the mind’ mean? Placebos orthodox treatment, Shang et generate real changes in brain function. tered to a patient to compare al stated in their conclusion its effects with those of a that the effect of homeopathic real drug, but sometimes for remedies was no greater than that Placebo is a Latin word for the psychological benefit of the of a placebo. Not that they had “I shall be pleasing, or accept- patient through his believing he no effect, but it was no greater able”. It is the first word of the is receiving treatment”. than that of a placebo. first antiphon of the Roman Rite of the Vespers for the Dead (!), However, placebos do benefit We skeptics are often happy to Placebo Domino, dating from the patients, and they are certainly accept the explanation that if a page placebos not inactive in the context in • The site of this activity in effect, and that in fact, as an inert which they are given. the brain placebo can have no effect per se, what we see is the effect of the • The most dramatic example of Why there is variation context in which the treatment this that I saw in clinical practice in the placebo effect from indi- is given. involved a young man on arti- vidual to individual ficial kidney treatment. When Neurophysiology of placebo • erythropoietin became available What are the implica- pain relief for the treatment of the severe tions for the classical drug trial anaemia seen so often in this format? Over the last 30 years, there situation, he was the first patient has been much interest in the neuro-physiological mechanisms in our unit to receive it. Erythro- There must be a of the placebo response. poietin is a hormone made in the physiological cause for healthy kidney, which increases placebo analgesia. In 1975, Hughes et al iden- the number of red cells in the tified in the brain two related blood and the amount of the oxy- pentapeptides (a chain of five gen-carrying haemoglobin. The amino acids linked together) synthetic version has achieved Psychological mechanisms with potent opium-like action. notoriety as a performance en- There are many more now iden- hancer in sport, for example in Those who study the psycho- tified. These compounds act the Tour de France. We were logical processes of the placebo on specific receptors on the all very enthusiastic about this effect cite two major mecha- membranes of neurones, and via improvement in management nisms. intracellular metabolic changes for our patient, and he was given Conditioning. Pavlov (1849- increase synaptic transmission. his first dose with much interest 1936) showed that dogs given They are made in the pituitary from all of us. That night he meals as a bell rang would and hypothalamus, and are called went home, recovered his bicycle subsequently salivate when the endorphins. from the shed where it had been bell rang despite not being given A digression undisturbed for many months, food. This process has been and rode all around his town explored in humans, who will In pharmacology the term with great energy and pleasure. experience pain relief when a agonist denotes a drug with an He hadn’t heard the information placebo is substituted for a pain effect, and antagonist, a drug that the drug took three weeks to reliever when a sequence of ac- which specifically blocks the ef- act on the anaemia. tive analgesia has been associ- fect of the first substance. ated with an environmental cue.