Riassunto : L’ effetto nocebo è l’effetto psicobiologico dovuto al contesto psicosociale negativo che accompagna una terapia. Dal momento che lo studio dell’ anticipazione dolorifica prende in considerazione la fase temporale della “attesa dell’iperalgesia”, e considerando che – proprio come il nocebo – è possibile elicitarla con il solo uso di verbalizzazioni negative, questo modello può permettere di studiare la risposta nocebo. Ad oggi infatti non si dispone di dati univoci circa le aree coinvolte in questi processi e circa il (...) ruolo cognitivo da queste ricoperto. Abbiamo condotto una meta-analisi su studi fMRI di anticipazione dolorifica su cui applicare un modello di connettività meta-analitica su due regioni di interesse: la corteccia cingolata e l’insula anteriori, le cui attivazioni sembrerebbero correlano ai domini comportamentali dell’azione, dell’emozione e della percezione. I risultati avvalorano l’ipotesi dell’esistenza di un sistema supramodale altamente distribuito, attivato dall’anticipazione del dolore, e, infine, volto all’elaborazione delle informazioni e all’auto-regolazione delle risposte adattive all’ambiente. Parole chiave : Placebo; Nocebo; Dolore; Correlati neurali; Comportamento umano Placebo Analgesia, Pain Anticipation, and the Possible Neural Correlates of Nocebo Effect: The nocebo effect is a psychobiological effect that occurs when a negative psychosocial context that accompanies a therapy. Since the study of pain anticipation takes into account the temporal phase of the “expectation of hyperalgesia”, and considering that it is possible to stimulate such anticipatory processes merely through the use of negative verbalizations, this model is appropriate for studying the nocebo response. To date, there are no univocal data about the brain areas involved in these processes or their cognitive roles. We conducted a meta-analysis on pain anticipation fMRI studies. We then applied a meta-analytic connectivity model to activations in the anterior cingulate cortex and the anterior insula, which correlate with the behavioral domains of action, emotion and perception. Our results support the hypothesis that there is a highly-distributed supramodal system, activated by pain anticipation, for processing information that enhances the self-regulation of adaptive responses to the environment. Keywords : Placebo; Nocebo; Pain; Neural Correlates; Human Behaviour. (shrink)

There is compelling evidence that pain experience is influenced by cognitive states. We explore one specific form of such influence, namely placebo analgesia, and examine its relevance for the cognitive penetration debate in philosophy of mind. We single out as important a form of influence on experience that we termradical cognitive penetration,and argue that some cases of placebo analgesia constitute compelling instances of this phenomenon. Still, we urge caution in extrapolating from this to broader conclusions about (...) cognitive penetration in perceptual experience. Instead, we suggest that the cognitive penetration of pain raises distinctive psychological, epistemological, and ethical issues. (shrink)

This paper examines research on three hypnotic phenomena: suggested amnesia, suggested analgesia, and “trance logic.” For each case a social-psychological interpretation of hypnotic behavior as a voluntary response strategy is compared with the traditional special-process view that “good” hypnotic subjects have lost conscious control over suggestion-induced behavior. I conclude that it is inaccurate to describe hypnotically amnesic subjects as unable to recall the material they have been instructed to forget. Although amnesics present themselves as unable to remember, they in (...) fact retain control over retrieval processes and accommodate their recall (or lack of it) to the social demands of the test situation. Hypnotic suggestions of analgesia do not produce a dissociation of pain from phenomenal awareness. Nonhypnotic suggestions of analgesia and distractor tasks that deflect attention from the'noxious stimuli are as effective as hypnotic suggestions in producing reductions in reported pain. Moreover, when appropriately motivated, subjects low in hypnotic suggestibility report pain reductions as large as those reported by highly suggestible hypnotically analgesic subjects. Finally, the data fail to support the view that a tolerance for logical incongruity (i.e., trance logic) uniquely characterizes hypnotic responding. So-called trance-logic-governed responding appears to reflect the attempts of “good” subjects to meet implicit demands to report accurately what they experience. (shrink)

Discussions concerning the modularity of the pain system have been focused on questions regarding the cognitive penetrability of pain mechanisms. It has been claimed that phenomena such as placebo analgesia demonstrate that the pain system is cognitively penetrated; therefore, it is not encapsulated from central cognition. However, important arguments have been formulated which aim to show that cognitive penetrability does not in fact entail a lack of modularity of the pain system. This paper offers an alternative way to (...) reject the modularity of the pain system, which is independent from, but consistent with, the presence of cognitive penetration. It is proposed that, given the current knowledge regarding the functioning and the structure of the pain system, there are good reasons to accept that certain central cognitive mechanisms are part of the pain system. It is argued that such a ‘cognitive constitution’ of the pain system entails that the pain system is not modular. (shrink)

Health care providers are expected both to relieve pain and to provide anticipatory guidance regarding how much a procedure is going to hurt. Fulfilling those expectations is complicated by the cognitive modulation of pain perception. Warning people to expect pain or setting expectations for pain relief not only influences their subjective experience, but it also alters how nociceptive stimuli are processed throughout the sensory and discriminative pathways in the brain. In light of this, I reconsider the characterization of placebo (...) analgesia as pharmacologically inert and the use of it as deceptive. I show that placebo analgesia exploits the same physical mechanisms as proven analgesics and argue that it should be utilized to relieve pain. Additionally, I describe factors to help identify situations in which clinicians have the obligation to disclose the potential for pain coupled with ways of mitigating the risk of high-intensity pain by setting positive expectations. (shrink)

When someone steps on your toe on purpose, it seems to hurt more than when the person does the same thing unintentionally. The physical parameters of the harm may not differ—your toe is flattened in both cases—but the psychological experience of pain is changed nonetheless. Intentional harms are premeditated by another person and have the specific purpose of causing pain. In a sense, intended harms are events initiated by one mind to communicate meaning (malice) to another, and this could shape (...) the recipient’s experience. This study examined whether self-reported pain is indeed higher when the events producing the pain are understood as intentionally (as opposed to unintentionally) caused by another person. Although pain was traditionally conceived to be solely physical in nature (Aydede, 2005), its experience varies substantially with psychological context. The placebo analgesia effect, for example, is the reduction of pain without a change in physical stimulation when context, expectations, or sugar pills challenge the interpretation of a sensation as painful (e.g., Fields, 2008). The nocebo effect, in turn, is the experience of pain without any physical stimulation—as when participants report headaches when told that a (nonexistent) electric current is passing through their heads (Schweiger & Parducci, 1981). These variations in pain experience seem to depend on the meaning of the stimulus: A sugar pill is meant to decrease pain, whereas electric current is meant to increase pain. In an interpersonal context, the meaning of an action is derived from the would complete. perceiver’s perceptions of the actor’s intention (Clark, 1996). (shrink)

Converging data from different disciplines are showing the role of classical conditioning processes in the elaboration of human and animal behavior to be larger than previously supposed. Restricted views of classically conditioned responses as merely secretory, reflexive, or emotional are giving way to a broader conception that includes problem-solving, and other rule-governed behavior thought to be the exclusive province of either operant conditiońing or cognitive psychology. These new views have been accompanied by changes in the way conditioning is conducted and (...) evaluated. Data from a number of seemingly unrelated phenomena such as relapse to drug abuse by postaddicts, the placebo effect, and the immune response appear to involve classical conditioning processes. Classical conditioning, moreover, has been found to occur in simpler and simpler organisms and recently even demonstrated in brain slices and in utero. This target article will integrate the several research areas that have used the classical conditioning process as an explanatory model; it will challenge teleological interpretations of the classically conditioned CR and offer some basic principles for testing conditioning in diverse areas. (shrink)

We suggest that pain processing has a modular architecture. We begin by motivating the (widely assumed but seldom defended) conjecture that pain processing comprises inferential mechanisms. We then note that pain exhibits a characteristic form of judgement independence. On the assumption that pain processing is inferential, we argue that its judgement independence is indicative of modular (encapsulated) mechanisms. Indeed, we go further, suggesting that it renders the modularity of pain mechanisms a default hypothesis to be embraced pending convincing counterevidence. Finally, (...) we consider what a modular pain architecture might look like, and question alleged counterevidence to our proposal. (shrink)

It has been almost 20 years since the field of bioethics was galvanized by a controversial series of multinational AZT trials employing placebo controls on pregnant HIV-positive women in the developing world even though a standard of care existed in the sponsor countries. The trove of ethical investigations that followed was thoughtful and challenging, yet an important and problematic methodological assumption was left unexplored. In this article, I revisit the famous “double standard of care” case study in order to (...) offer novel consideration of the placebo orthodoxy that underlies much of the ethical debate. This majority view found in medical research is that placebo-controlled trials are methodologically superior to comparative trials that use active controls. I challenge this orthodoxy and argue that lives were unnecessarily lost in these trials as a result. Furthermore, current HIV research on vaccines and microbicides is now poised to repeat the error of subscribing to the placebo orthodoxy. (shrink)

It has been presumed within bioethics that the benefits and risks of treatments can be assessed independently of information disclosure to patients as part of the informed consent process. Research on placebo and nocebo effects indicates that this is not true for symptomatic treatments. The benefits and risks that patients experience from symptomatic treatments can be shaped powerfully by information about these treatments provided by clinicians. In this paper we discuss the implications of placebo and nocebo research for (...) risk–benefit assessment and informed consent. (shrink)

The placebo drug reactions from controlled trials were studied for the first time systematically for efficacy and the safety in drug data pooled from randomized, placebo-controlled, multicentre studies. Results: The efficacy of placebo on clinical symptoms and outcome varied between the therapeutic indications. However, no placebo effects on laboratory values, as e.g. blood glucose or Hb1c in diabetics, were noted. The frequency and type of placebo-induced adverse reactions also varied between indication groups. The placebo (...) side effect profile was largely similar to the side effect profile of the active treatment. The mechanisms of placebo effects are manyfold and varied (e.g. endorphin release, conditioning), much lacks explanation. Conclusion: Since the prescription of non-evidence based medicines (= pseudoplacebos) may clearly also result in serious adverse effects, such practice may not only be non-beneficial but may even be harmful. In clinical research, the judicious use of placebo remains essential to establish the efficacy and safety, safeguarding that patients receiving placebo will not be subject to harm and are fully informed. (shrink)

The concepts of placebos and placebo effects refer to extremely diverse phenomena. I recommend dissolving the concepts of placebos and placebo effects into loosely related groups of specific mechanisms, including (potentially among others) expectation-fulfillment, classical conditioning, and attentional-somatic feedback loops. If this approach is on the right track, it has three main implications for the ethics of informed consent. First, because of the expectation-fulfillment mechanism, the process of informing cannot be considered independently from the potential effects of treatment. (...) Obtaining informed consent influences the effects of treatment. This provides support for the authorized concealment and authorized deception paradigms, and perhaps even for outright deceptive placebo use. Second, doctors may easily fail to consider the potential benefits of conditioning, leading them to misjudge the trade-off between beneficence and autonomy. Third, how attentional-somatic feedback loops play out depends not only on the content of the informing process but also on its framing. This suggests a role for libertarian paternalism in clinical practice. (shrink)

The maternal‐fetal HIV transmission trials, conducted in developing countries in the 1990s, undoubtedly generated one of the most intense, high profile controversies in international research ethics. They sparked off a prolonged acrimonious and public debate and deeply divided the scientific community. They also provided an impetus for the revision of the Declaration of Helsinki – the most widely known guideline for international research. In this paper, I provide a brief summary of the context, outline the arguments for and against the (...) controversial use of placebo controls, and focus on particular areas that I believe merit further discussion or clarification. On balance, I argue that the researchers failed in their duties to protect the best interests of their research subjects, and to promote distributive justice. I discuss the difficulties of obtaining valid consent in this research context, and argue that it is unethical to inform women of their HIV status without at least offering them prophylactic treatment for their unborn children. A global view of justice, which endorses international equity, cannot be squared with international research guidelines that allow ‘local conditions’ to define the scope of duty to the control group. Finally, I suggest that the heated debate reflects a tension, if not an outright war, between two conflicting meta‐ethical systems, or incommensurable paradigms, that underpin scientific research involving human subjects. (shrink)

The placebo drug reactions from controlled trials were studied for the first time systematically for efficacy and the safety in drug data pooled from randomized, placebo-controlled, multicentre studies. Results: The efficacy of placebo on clinical symptoms and outcome varied between the therapeutic indications. However, no placebo effects on laboratory values, as e.g. blood glucose or Hb1c in diabetics, were noted. The frequency and type of placebo-induced adverse reactions also varied between indication groups. The placebo (...) side effect profile was largely similar to the side effect profile of the active treatment. The mechanisms of placebo effects are manyfold and varied (e.g. endorphin release, conditioning), much lacks explanation. Conclusion: Since the prescription of non-evidence based medicines (= pseudoplacebos) may clearly also result in serious adverse effects, such practice may not only be non-beneficial but may even be harmful. In clinical research, the judicious use of placebo remains essential to establish the efficacy and safety, safeguarding that patients receiving placebo will not be subject to harm and are fully informed. (shrink)

Placebos are allegedly used widely in general practice. Surveys reporting high level usage, however, have combined two categories, ‘pure’ and ‘impure’ placebos. The wide use of placebos is explained by the high level usage of impure placebos. In contrast, the prevalence of the use of pure placebos has been low. Traditional pure placebos are clinically ineffective treatments, whereas impure placebos form an ambiguous group of diverse treatments that are not always ineffective. In this paper, we focus on the impure (...) class='Hi'>placebo concept and demonstrate problems related to it. We also show that the common examples of impure placebos are not meaningful from the point of view of clinical practice. We conclude that the impure placebo is a scientifically misleading concept and should not be used in scientific or medical literature. The issues behind the concept, however, deserve serious attention in future research. (shrink)

Among medical researchers and clinicians the dominant view is that it is unethical to deceive patients by prescribing a placebo. This opinion is formalized in a recent policy issued by the American Medical Association (AMA [Chicago, IL]). Although placebos can be shown to be always safe, often effective, and sometimes necessary, doctors are now effectively prohibited from using them in clinical practice. I argue that the deceptive administration of placebos is not subject to the same moral objections that face (...) other forms of deception in clinical practice and medical research. Although deception is normally objectionable on the grounds that it limits autonomy and breaches trust, these grounds do not apply to placebos when they are prescribed within appropriate ethical limits. Patients have reason to prefer that doctors can prescribe placebos in ethically responsible ways. Hence, the AMA has an obligation to endorse and to promote the responsible use of deceptive placebos in clinical practice. (shrink)

The material presented at this conference pointed to a new dimension in the prosecution of activities that seek to relieve people of disease. While the simple instrument of the placebo may show those interested in the efficacy of physiologically active chemicals the extent to which the chemical of interest is actually active, the surprising outcome of such studies is that the placebo per se is worthy of more general study. This, when taken further, points to the ways in (...) which mind can influence the matter of the body. Of course, mind itself is an activity of matter, so we may retain the experimental approach that has told us about the world outside ourselves to examine the world that is inside our brains. New techniques and approaches to these once intractable problems are now in train. Where they will lead us we cannot predict, but as with the emergence of all new tools, we have to adopt those ethics that will carry us forward with the expectation that we will maximise benefits and minimise harms. (shrink)

A humorous short story about a company that tries marketing a placebo as a more expensive drug on the grounds that doing this will both maximize their profits and benefit the greatest number, since research shows the placebo to be highly effective if marketed as something else.

Philosophical debates about how best to explain emotion or placebo are debates about how best to characterise and explain the distinctive form of human responsiveness to the world that is the object of interest for each of those domains of inquiry. In emotion research, the cognitive theory of emotion faces several intractable problems. I discuss two of these: the problem of epistemic deficit and the problem of recalcitrant emotions. Cognitive explanations in Placebo Studies, such as response-expectancy and belief-based (...) explanations, also face the problem of epistemic deficit in addition to the problem of logically self-destructive true belief. While such considerations might motivate a retreat to affect, this brings its own problems. I argue that it is a particular version of cognitivism, representational cognitivism (Rep-Cog), that generates the paradoxes we encounter in emotion and placebo research. I propose that turning to nonrepresentational accounts of cognition will dissolve these paradoxes. As I move toward conclusion, I propose drawing on the ethnomethodological tradition to respecify human responsiveness to loci of significance in the lifeworld by undertaking ethnographies of members’ own situated methods for making intelligible and accountable their attitudinal and nonattitudinal responsiveness to loci of significance in their environment. (shrink)

Objectives -/- Surveys in various countries suggest 17% to 80% of doctors prescribe ‘placebos’ in routine practice, but prevalence of placebo use in UK primary care is unknown. Methods -/- We administered a web-based questionnaire to a representative sample of UK general practitioners. Following surveys conducted in other countries we divided placebos into ‘pure’ and ‘impure’. ‘Impure’ placebos are interventions with clear efficacy for certain conditions but are prescribed for ailments where their efficacy is unknown, such as antibiotics for (...) suspected viral infections. ‘Pure’ placebos are interventions such as sugar pills or saline injections without direct pharmacologically active ingredients for the condition being treated. We initiated the survey in April 2012. Two reminders were sent and electronic data collection closed after 4 weeks. Results -/- We surveyed 1715 general practitioners and 783 (46%) completed our questionnaire. Our respondents were similar to those of all registered UK doctors suggesting our results are generalizable. 12% (95% CI 10 to 15) of respondents used pure placebos while 97% (95% CI 96 to 98) used impure placebos at least once in their career. 1% of respondents used pure placebos, and 77% (95% CI 74 to 79) used impure placebos at least once per week. Most (66% for pure, 84% for impure) respondents stated placebos were ethical in some circumstances. Conclusion and implications -/- Placebo use is common in primary care but questions remain about their benefits, harms, costs, and whether they can be delivered ethically. Further research is required to investigate ethically acceptable and cost-effective placebo interventions. (shrink)

Robin Nunn has argued that we should stop using the terms ‘placebo’ and ‘placebo effect’. I argue in support of Nunn’s position by considering the logic of why we perform placebo comparisons. Like all comparisons, placebo comparison is just a case of comparing one thing with another, but it is a mistake, I argue, to think of placebo comparison as a case where something is compared to ‘a placebo’. Rather, placebo comparison should be (...) understood as a situation which sets-up the treatment and control groups in a particular way; not as a case involving objects or procedures called ‘placebos’ employed in order to control for ‘placebo effects’. (shrink)

It is widely believed that medically inert treatments (“placebos”) can bring about therapeutic benefits. There is also evidence that medically active treatments may also have “placebo” effects. Since anything that has the potential to benefit patients ought to be exploited, subject to appropriate ethical standards, it has been suggested that more should be done to investigate and exploit the power of the placebo for therapeutic benefit. I explore the acute epistemic and ethical constraints that such exploitation is likely (...) to face, and conclude that effective exploitation is unlikely. (shrink)

Randomised clinical trials involve procedures such as randomisation, blinding, and placebo use, which are not part of standard medical care. Patients asked to participate in RCTs often experience difficulties in understanding the meaning of these and their justification.

Placebos are commonly defined as ineffective treatments. They are treatments that lack a known mechanism linking their properties to the properties of the condition on which treatment aims to intervene. Given this, the fact that placebos can have substantial therapeutic effects looks puzzling. The puzzle, we argue, arises from the relationship placebos present between culturally meaningful entities, our intentional relationship to the environment and bodily effects. How can a mere attitude toward a treatment result in appropriate bodily changes? We argue (...) that an ‘enactive’ conception of cognition accommodates and renders intelligible the phenomenon of placebo effects. Enactivism depicts an organism’s adaptive bodily processes, its intentional directedness, and the meaningful properties of its environment as co-emergent aspects of a single dynamic system. In doing so it provides an account of the interrelations between mind, body and world that demystifies placebo effects. (shrink)

In this paper, Isuggest that placebo effects, as we know them today, should be understood as experimental phenomena, low-level regularities whose causal structure is grasped through particular experimental designs with little theoretical guidance. Focusing on placebo interventions with needles for pain reduction -one of the few placebo regularities that seems to arise in meta-analytical studies- I discuss the extent to which it is possible to decompose the different factors at play through more fine-grained randomized clinical trials. My (...) sceptical argument is twofold. On the one hand, I argue that experiments alone are not enough to standardize interventions, and that it is necessary to include theories. On the other hand, I argue that the social interactions that seem to be part of placebo effects are difficult, if not impossible, to blind. Therefore, the measurement biases arising from the participants’ reactivity to the experimental setup cannot be controlled for. Further decomposition of placebo effects requires a theoretical account of the existing experimental regularities that may guide further tests. (shrink)

Several authors have recently argued that psychotherapy, as it is commonly practiced, is deceptive and undermines patients’ ability to give informed consent to treatment. This ‘deception’ claim is based on the findings that some, and possibly most, of the ameliorative effects in psychotherapeutic interventions are mediated by therapeutic common factors shared by successful treatments, rather than because of theory-specific techniques. These findings have led to claims that psychotherapy is, at least partly, likely a placebo, and that practitioners of psychotherapy (...) have a duty to ‘go open’ to patients about the role of common factors in therapy ; to not ‘go open’ is supposed to unjustly restrict patients’ autonomy. This paper makes two related arguments against the ‘go open’ claim. While therapies ought to provide patients with sufficient information to make informed treatment decisions, informed consent does not require that practitioners ‘go open’ about therapeutic common factors in psychotherapy, and clarity about the mechanisms of change in psychotherapy shows us that the common-factors findings are consistent with, rather than undermining of, the truth of many theory-specific forms of psychotherapy; psychotherapy, as it is commonly practiced, is not deceptive and is not a placebo. The call to ‘go open’ should be resisted and may have serious detrimental effects on patients via the dissemination of a false view about how therapy works. (shrink)

Placebo-controlled trials are held by many, including regulators at agencies like the United States Food and Drug Administration, to be the gold standard in the assessment of new medical interventions. Yet the use of placebo controls in clinical trials has been the focus of considerable controversy. In this two-part article, we challenge a number of common beliefs concerning the value of placebo controls. Part I critiques statistical and other scientific justifications for the use of placebo controls (...) in clinical research. The continued use of placebo controls in clinical trials on diseases for which accepted treatment exists raises equally important ethical, legal, and regulatory issues for which various justifications have been given. Defense of this practice relies on normative as well as empirical myths.In their attack on the prevailing use of placebo controls, Kenneth Rothman and Karin Michels emphasize that this practice stands in violation of the World Medical Association's guidelines on the ethics of human experimentation, most commonly known as the Helsinki Declaration. (shrink)

Background Intensivists must provide enough analgesia and sedation to ensure dying patients receive good palliative care. However, if it is perceived that too much is given, they risk prosecution for committing euthanasia. The goal of this study is to develop consensus guidelines on analgesia and sedation in dying intensive care unit patients that help distinguish palliative care from euthanasia. Methods Using the Delphi technique, panelists rated levels of agreement with statements describing how analgesics and sedatives should be given (...) to dying ICU patients and how palliative care should be distinguished from euthanasia. Participants were drawn from 3 panels: 1) Canadian Academic Adult Intensive Care Fellowship program directors and Intensive Care division chiefs (N = 9); 2) Deputy chief provincial coroners (N = 5); 3) Validation panel of Intensivists attending the Canadian Critical Care Trials Group meeting (N = 12). Results After three Delphi rounds, consensus was achieved on 16 statements encompassing the role of palliative care in the intensive care unit, the management of pain and suffering, current areas of controversy, and ways of improving palliative care in the ICU. Conclusion Consensus guidelines were developed to guide the administration of analgesics and sedatives to dying ICU patients and to help distinguish palliative care from euthanasia. (shrink)

While a significant body of bioethical literature considers how the placebo effect might introduce a conflict between autonomy and beneficence, the link between justice and the placebo effect has been neglected. Here, we bring together disparate evidence from the field of placebo studies and research on health inequalities related to race and ethnicity, and argue that, collectively, this evidence may provide the basis for an unacknowledged route by which health disparities are exacerbated. This route is constituted by (...) an uneven distribution of placebo effects, resulting from differences in expressions of physician warmth and empathy, as well as support and patient engagement, across racial and ethnic lines. In a discussion of the ethical implications of this connection, we argue that this contribution to health disparities is a source of injustice, consider ways in which these disparities might be ameliorated and suggest that this conclusion is likely to extend to other realms of inequality as well. (shrink)

The paper presents major ethical, legal and methodological problems related to the use of placebo in mental disorders, especially in depression. It is pointed out that although authoritative groups of experts and numerous publications in the field of psychopharmacology indicate advisability of the double blind design with placebo in clinical trials of antidepressants, in recent years there have been more and more voices questioning legitimacy of this method. Objections of an ethical nature are raised, and reliability of this (...) approach is put into doubt from the methodological viewpoint. These issues are discussed in more detail in the paper. Available alternative solutions should be implemented in psychotropic drug studies. The author shares these objections and doubts of an ethical nature, and believes that the placebo procedure is not a necessity in clinical trials of antidepressants. (shrink)

In this paper, I respond to some criticisms of Greenwood (1996) advanced by Grunbaum (1996) and Erwin (1996). I argue that Grunbaum's problematic account of "placebo effects" and placebo control treatments does not really address, far less resolve, the problems with experimental evaluations of psychotherapy documented in my original paper.

Placebo effects raise some fundamental questions concerning the nature of clinical and medical research. This Element begins with an overview of the different roles placebos play, followed by a survey of significant studies and dominant views about placebo mechanisms. It then critically examines the concept of placebo and offers a new definition that avoids the pitfalls of other attempts. The main philosophical lesson is that background medical theories provide the ontology for clinical and medical research. Because these (...) theories often contain incoherent and arbitrary classifications, the concept of placebo inherits the same messiness. The Element concludes by highlighting some impending challenges for placebo studies. (shrink)

Mazur & Booth present an intriguing model of the relationship between circulating testosterone levels and dominance behaviour in man, but their review of studies on testosterone–behaviour relationships in man is selective. Much of the evidence they cite is correlational in nature. Placebo-controlled manipulations of testosterone levels are required to test their hypothesis that dominance levels are testosterone-dependent in man. The changes in testosterone level that follow behavioural experience may be a consequence of stress. Testosterone levels in man are determined (...) by a wide variety of factors, and a multivariate approach is required. (shrink)

Despite the conceptual problems in identifying the placebo effect, an increasing number of multidisciplinary inquiries rest on the assumption that there is a distinct class of effects, placebo effects. In this chapter, I argue against this assumption. I present cases and characterizations of the placebo effect as offered in the literature, and argue that the latter are subject to insurmountable problems. Moreover, I argue that identification of placebo effects as such is not useful for the three (...) main purposes offered in the literature. I then offer suggestions for why it may remain intuitive that some effects are placebo effects and close by noting the potential benefits of ultimately explaining away these intuitions. (shrink)

The placebo effect has puzzled scientists for centuries. Philosopher Dien Ho argues that we now know how it works, and that this should transform our understanding of the relationship between mind and body. We must stop thinking of improvements in health due to placebo as somehow less real than those due to other medicines: there can no longer be a clean distinction between ill-health that’s “all in the head” and ill-health that involves a malfunctioning body. Ho argues that (...) our improved understanding of placebos means that doctors should now harness their power in treatment, especially since research shows that they can be effective even when patients are told that they’re taking a placebo. (shrink)

Evidence that placebo acupuncture is an effective treatment for chronic pain presents a puzzle: how do placebo needles appearing to patients to penetrate the body, but instead sitting on the skin’s surface in the manner of a tactile stimulus, evoke a healing response? Previous accounts of ritual touch healing in which patients often described enhanced touch sensations suggest an embodied healing mechanism. In this qualitative study, we asked a subset of patients in a singleblind randomized trial in irritable (...) bowel syndrome to describe their treatment experiences while undergoing placebo treament. Analysis focused on patients’ unprompted descriptions of any enhanced touch sensations and any significance patients assigned to the sensations. We found in 5/6 cases, patients associated sensations including “warmth” and “tingling” with treatment efficacy. The conclusion offers a “neurophenomenological” account of the placebo effect by considering dynamic effects of attentional filtering on early sensory cortices, possibly underlying the phenomenology of placebo acupuncture. (shrink)

The achievement of optimal therapeutic results presupposes the use of appropriate treatment combined with maximal utilization of placebo effects. These aims may sometimes be difficult to satisfy in randomized clinical trials (RCTs). The question thus arises whether there is a conflict between the goals of therapy and those of experimental research; and if so, to what extent, and how is it handled in practice by clinicians and researchers. Various ethical problems have been discussed in several reports connected with RCTs. (...) But we have found no discussion concerning the conflict between obtaining informed consent and promoting optimal placebo effects. Information about RCTs can be given in various ways. Sometimes appropriate information about RCTs to patients involves non-optimal utilization of placebo effects. This gives rise to ethical and methodological problems, which are discussed in this article. (shrink)

National and international research cultures for the innovation of new medicines involve various value claims about the ethics of the placebo entity as differentiating comparator. Yet, in turn, the instantiation of the placebo comparator as cultural artefact for the creation and identification of the ‘control group’ depends also upon prior social understandings of ‘comparability’. Reading back the ethics controversies surrounding the Risperidone psychiatry trials in India, the paper illustrates why drug efficacies need to be studied not only through (...) comparative techniques such as randomised controlled trials, but also through analytical modes of inquiry that can begin to place the problem of efficacy within particular social and cultural contexts, as well as across disciplines. It is suggested that future bioethics debates could benefit from a revised conception of the interdisciplinary placebo — one that is rooted in ‘placebo politics’ and that listens responsively to the voices of the global South. (shrink)

What’s so bad about the placebo effect? John Worrall discusses the recent Nurofen labelling “scandal”.

The current controversy as to the proper role of the placebo control in the evaluation of new treatments for schizophrenia requires an analysis that is sensitive to both ethical and scientific issues. Clinical equipoise, widely regarded as the moral foundation of the randomized controlled trial (RCT), requires the use of best available treatment as the control in RCT. Scientific criticisms of the use of an active control are examined and none present an insuperable barrier to the use of an (...) active control. Indeed, scrutiny of the most recent argument for the use of placebo controls, 'assay sensitivity', suggests that the use of placebo may be the cause of the problem pointed to. Scientific, regulatory, ethical and legal advantages of the use of an active control are described. While the use of a placebo control may be acceptable in carefully defined circumstances, in most cases the use of an active control in schizophrenia research is ethically and scientifically preferable. (shrink)

This article considers issues concerning cases where the use of placebo is lawful or is not lawful under aspects of German criminal law. It will differentiate between cases of individual therapy and cases of supervised experiments within the scope of medical tests. Thereby, it reveals that a medication of placebo with regard to an individual patient seems to be lawful if there is no alternative possibility of a better treatment using a chemically effective medicine and if the limits (...) of presumed consent are complied with. On the other hand, in the context of the supervised experiment, the assignment of a patient to a group treated with placebo is only lawful if the patient has been fully informed about the possibilities of a treatment and if the patient has given consent to it. (shrink)

The UK Medical Research Council, in order to further its mission of maintaining and improving human health, supports a substantial number of clinical trials on a wide variety of medical questions; some of these trials involve the use of placebos as controls or to maintain blinding. Before providing support, proposed trials are carefully reviewed to assess scientific quality, and to determine whether a placebo is required and is ethical — in addition to ethics review by independent Research Ethics Committees. (...) Some questions such as the choice of placebos in trials in developing countries, in surgical trials and those involving alternative medicine require consideration of additional, specific issues. Involvement of consumers in MRC work has been increasing and includes the establishment of a Consumer Liaison Group; members of this group comment on patient information leaflets for clinical trials, helping to improve patient understanding of trials and ensuring topics like placebo use are explained clearly. Views differ on the value of placebos in clinical care and on their mechanism of action; continuing research is helping to clarify the issues. (shrink)

Abstract. The placebo effect these days is no longer merely the insubstantial, subjective response that some patients have to a sham treatment, like a sugar pill. It has been reconceived as a powerful mind-body phenomenon. Because of this, it has also emerged as a complex reference point in a number of high-stakes conversations about the metaphysical significance of experiences of religious healing, the possible health benefits of being religious, and the feasibility of using double-blind placebo-controlled trials to investigate (...) the efficacy of prayer. In each of these conversations, the placebo effect is always pointing toward some larger issue, serving some larger agenda. The agendas, though, tend to pull in different directions, leading to a situation that feels at once fractured and stalemated. This essay reviews the main areas of interest, and proposes some specific issues where humanistic scholars of religion in particular might be able to introduce constructive and creative new perspectives. (shrink)

Often regarded simply as a nuisance in clinical drug trials in which the aim is to separate drug response from placebo response in a statistically significant manner, the placebo response has important implications. These implications relate to the nature of illness, the study of non-specific factors in the treatment setting that are related to clinical improvement, methods of enhancing these non-specific sources of benefit, and the neurobiology that is associated with the placebo response. Specific sources of clinical (...) improvement in medical and psychological treatment generally consist of drugs or clear interventions that appear to directly contribute to the desired treatment. Non-specific factors, on the other hand, include the clinician–patient relationship, installation of hope, relationship with authority, and other such factors that are more implicit to treatment and may contribute to the placebo response. Our understanding of how these non-specific aspects of treatment relate to clinical improvement and ways of enhancing these non-pharmacological elements of therapy may form important aspects of treatment. Furthermore, an important, albeit potentially overlooked element of the placebo response are clinical-trial designs and methodologies, themselves. Specific neurobiological changes also appear to be associated with the placebo response in at least some cases. Finally, it is suggested that the placebo response may in some instances represent a type of brain plasticity in which expectation and desire — agency — can result in specific changes in brain function that either may mirror or differ from the effects of certain drugs. (shrink)

This paper considers the ethics of placebo‐controlled trials in developing countries, where a treatment already exists but is not available due to the low local standard of care. Such trials would not be permitted in more developed nations where a higher standard of care is available. I argue that there are moral intuitions against such trials, but a further intuition that if the trials were aimed at producing treatment options for the developing world, that would be more permissible than (...) if the trials were designed with the benefit of rich world people in mind. An approach based upon GA Cohen's work on interpersonal justifiability is suggested to allow us to explain these intuitions. Cohen's framework shows that these trials are ethically problematic because the inequality in healthcare provision between developing and developed nations that allows them to take place is at least partly the pharmaceutical corporations’ fault. Following Cohen's argument, this means the trials are non‐comprehensively justified. This allows for a more complete explanation of our intuitions than to consider such trials as cases of exploitation, because intuitions on the ethicacy of research can vary even when the exploitation relation remains the same. It is then established that there is good empirical evidence to believe that pharmaceutical corporations do fail the interpersonal justifiability test. The policy implications of this judgement are then considered, and it is suggested that the framework might be equally applicable to examining the permissibility of research conducted on vulnerable people within more developed nations. (shrink)

Use of a placebo control in surgical trials is a divisive issue. We argue that, in principle, placebo controls for surgery are necessary in the same way as for medicine. However, there are important differences between these types of trial, which both increase justification and limit application of surgical studies. We propose that surgical randomised placebo-controlled trials are ethical if certain conditions are fulfilled: the presence of equipoise, defined as a lack of unbiased evidence for efficacy of (...) an intervention; clinically important research question; the risk to patients is minimised and reasonable; there is uncertainty about treatment allocation rather than deception; there is preliminary evidence for efficacy, which justifies a placebo-controlled design; and ideally, the placebo procedure should have some direct benefit to the patient, for example, as a diagnostic tool. Placebo-controlled trials in surgery will most often be justified when surgery is performed to improve function or relieve symptoms and when objective outcomes are not available, while the risk of mortality or significant morbidity is low. In line with medical placebo-controlled trials, the surgical trial should be sufficiently powered and standardised so that its results are valid, consent should be valid, the standard treatment or rescue medication should be provided if possible, and after the trial, the patients should be told which treatment they received and there should be provision for post-trial care if the study may result in long-term negative effects. We comment and contrast our guidelines with those of the American Medical Association. (shrink)