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International Review of Neurobiology 2020
Topics: Humans; Nervous System Diseases; Placebo Effect
PubMed: 32563295
DOI: 10.1016/S0074-7742(20)30100-8 -
BMJ Open Oct 2023This review aimed to summarise the existing knowledge about placebo and nocebo effects associated with pharmacological interventions and their mechanisms. (Review)
Review
OBJECTIVES
This review aimed to summarise the existing knowledge about placebo and nocebo effects associated with pharmacological interventions and their mechanisms.
DESIGN
Umbrella review, adopting the Assessment of Multiple Systematic Reviews 2 tool for critical appraisal.
DATA SOURCES
MEDLINE/PubMed, Scopus, Web of Science, PsycINFO, Cochrane Central Register of Controlled Trial were searched in September 2022, without any time restriction, for systematic reviews, narrative reviews, original articles. Results were summarised through narrative synthesis, tables, 95% CI.
OUTCOME MEASURES
Mechanisms underlying placebo/nocebo effects and/or their effect sizes.
RESULTS
The databases search identified 372 studies, for a total of 158 312 participants, comprising 41 systematic reviews, 312 narrative reviews and 19 original articles. Seventy-three per cent of the examined systematic reviews were of high quality.Our findings revealed that mechanisms underlying placebo and/or nocebo effects have been characterised, at least in part, for: pain, non-noxious somatic sensation, Parkinson's disease, migraine, sleep disorders, intellectual disability, depression, anxiety, dementia, addiction, gynaecological disorders, attention-deficit hyperactivity disorder, immune and endocrine systems, cardiovascular and respiratory systems, gastrointestinal disorders, skin diseases, influenza and related vaccines, oncology, obesity, physical and cognitive performance. Their magnitude ranged from 0.08 to 2.01 (95% CI 0.37 to 0.89) for placebo effects and from 0.32 to 0.90 (95% CI 0.24 to 1.00) for nocebo effects.
CONCLUSIONS
This study provides a valuable tool for clinicians and researchers, identifying both results ready for clinical practice and gaps to address in the near future.
FUNDING
Università Cattolica del Sacro Cuore, Milan, Italy with the 'Finanziamento Ponte 2022' grant.
PROSPERO REGISTRATION NUMBER
CRD42023392281.
Topics: Humans; Nocebo Effect; Systematic Reviews as Topic; Placebo Effect; Attention Deficit Disorder with Hyperactivity; Anxiety
PubMed: 37848293
DOI: 10.1136/bmjopen-2023-077243 -
International Review of Neurobiology 2018In this chapter, I review basic tenets of response expectancy theory (Kirsch, 1985), beginning with the important distinction between response expectancies and stimulus... (Review)
Review
In this chapter, I review basic tenets of response expectancy theory (Kirsch, 1985), beginning with the important distinction between response expectancies and stimulus expectancies. Although both can affect experience, the effects of response expectancies are stronger and more resistant to extinction than those of stimulus expectancies. Further, response expectancies are especially important to understanding placebo effects. The response expectancy framework is consistent with and has been amplified by the Bayesian model of predictive coding. Clinical implications of these phenomena are exemplified.
Topics: Anticipation, Psychological; Conditioning, Psychological; Humans; Perception; Placebo Effect; Psychological Theory
PubMed: 29681336
DOI: 10.1016/bs.irn.2018.01.003 -
The Journal of Medicine and Philosophy Jun 2021This article presents and defends an integrated view of the placebo effect, termed "affective-meaning-making" model, which draws from theoretical reflection, clinical...
This article presents and defends an integrated view of the placebo effect, termed "affective-meaning-making" model, which draws from theoretical reflection, clinical outcomes, and neurophysiological findings. We consider the theoretical limitations of those proposals associated with the "meaning view" on the placebo effect which (a) leave the general aspects of meaning unspecified, (b) fail to analyze fully the role of emotions and affect, and (c) establish no clear connection between the theoretical, physiological, and psychological aspects of the effect. We point out that a promising way to overcome these limitations is given by grounding the placebo effect on Peirce's theory of meaning, in which the role of the meaning constitution and change is placed in logical and objective structures. We also show the connection between our theoretical proposal and the appraisal theory and integrate it with emotion regulation.
Topics: Emotions; Humans; Placebo Effect
PubMed: 34106280
DOI: 10.1093/jmp/jhab002 -
Pain Management Nov 2018
Topics: Analgesia; Brain; Humans; Neuroimaging; Neurosciences; Personality; Placebo Effect
PubMed: 30873895
DOI: 10.2217/pmt-2018-0054 -
International Review of Neurobiology 2018Why pain can be relieved with placebos is heavily debated. The term "placebo effect," implies that the placebo treatment induces pain relief which is imprecise because... (Review)
Review
Why pain can be relieved with placebos is heavily debated. The term "placebo effect," implies that the placebo treatment induces pain relief which is imprecise because it is the mental cueing to the context of treatment and not the placebo itself that can reduce pain. This essay reverts to fundamentals of perception that have been used to explain how context generates predictions that can in turn effect the process of processing, organizing and interpreting of sensory inputs received from the periphery. We reinterpret placebo effect as a neurobiological phenomenon that occurs through the process of reward and aversive learning. The brain uses learnt information to generate predictions. The perceptual processes adjust the experience of pain to fit with the predictions generated from prior information. Placebo effect is thus understandably a result of the expectations and mental states that result from engaging in the process of treatment. These processes have teleological roots in ancient medicine and are the context that produces these responses is transforming with the evolution of modern medicine. Thus, when placebo effect is observed, the potent agent that induces pain reduction is not the placebo itself, but the mental cueing to the context of taking treatment.
Topics: Brain; Cues; Ethical Theory; Humans; Pain; Pain Management; Placebo Effect
PubMed: 30146049
DOI: 10.1016/bs.irn.2018.07.017 -
Obstetrics and Gynecology Dec 2018
Topics: Female; Humans; Placebo Effect; Sexual Dysfunction, Physiological
PubMed: 30461676
DOI: 10.1097/AOG.0000000000002986 -
International Review of Neurobiology 2018The placebo and psychotherapy are both effective psychological interventions. Next to being characterized by their own and specific controversies and debates, there is a... (Review)
Review
The placebo and psychotherapy are both effective psychological interventions. Next to being characterized by their own and specific controversies and debates, there is a persistent-and least for psychotherapy-looming notion that these two interventions share more than just the first letter. Based on Grünbaum's influential conceptualization of placebo, this chapter critically reviews both the time-honored claim that psychotherapy is a placebo as well as the argument that the placebo concept does not translate to psychotherapy. We conclude that there is an unwanted proximity between these two interventions and that empirical attempts to separate the "wheat from the chaff" in psychotherapy research face several distinctive challenges and thus are often methodologically comprised by the integrity of the placebo. However, drawing on recent, innovative research, we conclude that psychotherapy can be saved, i.e., shown to be distinct from the placebo, by employing study designs derived from the placebo research. We conclude that the placebo concept has profound implications for psychotherapy, psychotherapy research, and last but not least its ethical practice.
Topics: Humans; Placebo Effect; Psychotherapy
PubMed: 29681328
DOI: 10.1016/bs.irn.2018.01.013 -
Journal of Clinical Sleep Medicine :... May 2021Hunasikatti M. Real effect vs placebo effect. . 2021;17(5):1141.
Hunasikatti M. Real effect vs placebo effect. . 2021;17(5):1141.
Topics: Double-Blind Method; Humans; Placebo Effect
PubMed: 33560205
DOI: 10.5664/jcsm.9092 -
Transfusion Medicine (Oxford, England) Apr 2022Our own observations suggested that placebo and nocebo effects may occur with transfusions. However these effects seem to have been poorly studied. (Review)
Review
BACKGROUND
Our own observations suggested that placebo and nocebo effects may occur with transfusions. However these effects seem to have been poorly studied.
OBJECTIVES
To examine published information on, and draw attention to the possibility of, placebo and nocebo effects with transfusion.
METHODS
Focused literature review.
RESULTS
There is some information on placebo effects with clotting factors and this effect appears modest at best. There is very little published information on this regarding other fresh blood components. Although unknown biologic effects cannot be ruled out, there are hints that placebo effects might operate - especially with red blood cell transfusions. There is practically no information on nocebo effects with transfusions.
CONCLUSIONS
There are ways of surmounting the practical and ethical difficulties involved, and obtaining better information on both types of effects. Individualised, contextualised, informed consenting of transfusion recipients may help to enhance placebo, and reduce nocebo, effects. This may be supportable ethically, and desirable clinically, and financially.
Topics: Humans; Informed Consent; Nocebo Effect; Placebo Effect; Surveys and Questionnaires; Transfusion Medicine
PubMed: 35193168
DOI: 10.1111/tme.12857