{"id":8083,"date":"2026-07-19T16:32:47","date_gmt":"2026-07-19T14:32:47","guid":{"rendered":"https:\/\/blueportance.com\/knowledge-base\/expert-guides\/understanding-pain\/placebo-nocebo-effect\/"},"modified":"2026-10-25T22:43:30","modified_gmt":"2026-10-25T21:43:30","slug":"placebo-nocebo-effect","status":"publish","type":"page","link":"https:\/\/blueportance.com\/en\/knowledge-base\/expert-guides\/understanding-pain\/placebo-nocebo-effect\/","title":{"rendered":"KB 3_Expert Guide_01_Understanding Pain_12_Placebo and Nocebo Effect"},"content":{"rendered":"\n\n  <style>\n    body{font-family:Arial,sans-serif;line-height:1.65;padding:20px;color:#333}\n    .bp-q-breadcrumb{font-size:.85rem;color:#6b7280;margin:0 0 20px}\n    .bp-q-breadcrumb a{color:#2a7fba;text-decoration:none}\n    h1{color:#0e2a47;font-size:1.8rem;line-height:1.25;margin:0 0 22px}\n    h2{color:#1a4d72;margin-top:42px;line-height:1.3}\n    h3{color:#0e2a47;margin-top:28px}\n    p{margin:0 0 16px}\n    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#d39b22;border-radius:6px;background:#fff8e1;color:#5a4a00;font-size:.9rem}\n    .bp-inline-ref{white-space:nowrap;font-size:.88em;color:#5f6f7d}\n    @media(max-width:640px){body{padding:16px}h1{font-size:1.5rem}table{display:block;overflow-x:auto}}\n    .bp-bdc-toc{background:#f8fbff;border:1px solid #dbeaf7;border-radius:9px;padding:18px 22px;margin:24px 0 32px}\n    .bp-bdc-toc h2{margin:0 0 10px;font-size:1rem;color:#1a4d72}\n    .bp-bdc-toc ul{margin:0;padding-left:20px;list-style:none}\n    .bp-bdc-toc li{margin-bottom:6px;font-size:.92rem}\n    .bp-bdc-toc a{color:#2a7fba;text-decoration:none}\n    .bp-bdc-toc a:hover{text-decoration:underline}\n  <\/style>\n<style>\n.bp-bdc-breadcrumb{max-width:900px;margin:0 auto;padding:20px 16px 0;font-size:.85rem;color:#6b7280;}\n.bp-bdc-breadcrumb a{color:#2a7fba;text-decoration:none;}\n.bp-bdc-breadcrumb a:hover{text-decoration:underline;}\n<\/style>\n\n<nav class=\"bp-bdc-breadcrumb\" aria-label=\"Breadcrumb\">\n<a href=\"\/en\/\">Blue Portance<\/a> \u2192 <a href=\"https:\/\/blueportance.com\/en\/knowledge-base\/\">Knowledge Base<\/a> \u2192 <a href=\"https:\/\/blueportance.com\/en\/knowledge-base\/expert-guides\/understanding-pain\/\">Understanding Pain<\/a> \u2192 Placebo and Nocebo Effects\n<\/nav>\n\n<div class=\"bp-bdc-header-card\">\n  <div class=\"bp-bdc-kicker\">Blue Portance Expert Guides<\/div>\n  <div class=\"bp-bdc-rule\"><\/div>\n  <div class=\"bp-bdc-dossier-title\">Understanding Pain<\/div>\n  <div class=\"bp-bdc-dossier-subtitle\">The biological, mechanical, and neurophysiological mechanisms of pain.<\/div>\n<\/div>\n\n<p class=\"bp-bdc-dossier-link\">\n  This article is part of the Expert Guide\n  <a href=\"https:\/\/blueportance.com\/en\/knowledge-base\/expert-guides\/understanding-pain\/\">\u201cUnderstanding Pain\u201d<\/a>.\n<\/p>\n\n<span class=\"bp-pillar-badge\">Guide conclusion \u2014 Blue Portance Knowledge Base<\/span>\n\n<h1>When the Brain Can Take Back Control: Understanding the Placebo Effect Without Misconceptions<\/h1>\n\n<div class=\"bp-bdc-epistemic\">\n  <strong>Epistemic note<\/strong> \u2014 This article does not suggest replacing a treatment with a placebo, nor does it call into question the effectiveness of the mechanical, pharmacological, surgical, or rehabilitation treatments presented in this guide. It sets out what contemporary neuroscience documents about the biological mechanisms through which the therapeutic context itself can modulate pain.\n<\/div>\n\n<section class=\"bp-summary\">\n  <p>\n    <strong>Summary<\/strong> \u2014 The placebo effect is neither imaginary nor proof that the pain was not real:\n    it corresponds to measurable changes in the way the nervous system anticipates, processes, and modulates\n    pain. Indeed, imaging studies show that, in people who respond to a placebo, some brain regions engaged during opioid analgesia are also engaged. The placebo effect can thus\n    mobilize endogenous modulation systems that already exist in the brain, particularly in people who\n    respond to it. Understanding this mechanism also helps us understand its opposite, the nocebo effect. It thus brings\n    the guiding thread of this guide full circle: the living organism is an adaptive system, and the brain helps coordinate\n    this whole, in constant interaction with the information coming from the body and the environment.\n  <\/p>\n<\/section>\n\n<nav class=\"bp-bdc-toc\" aria-label=\"Table of contents\">\n  <h2>Table of Contents<\/h2>\n  <ul>\n      <li><a href=\"#pourquoi-cet-article\">Why this article?<\/a><\/li>\n      <li><a href=\"#le-cerveau-ne-subit-pas-il-anticipe\">The brain is not passive: it anticipates<\/a><\/li>\n      <li><a href=\"#un-veritable-systeme-biologique-de-modulation\">A genuine biological modulation system<\/a><\/li>\n      <li><a href=\"#le-placebo-ne-remplace-pas-un-traitement\">A placebo does not replace a treatment<\/a><\/li>\n      <li><a href=\"#l-effet-inverse-existe-aussi-le-nocebo\">The opposite effect also exists: the nocebo effect<\/a><\/li>\n      <li><a href=\"#une-nouvelle-lecture-du-soin\">A new way of understanding care<\/a><\/li>\n      <li><a href=\"#le-mot-de-la-fin-une-medecine-qui-mobilise-tout-le-vivant\">The final word: a medicine that engages the whole living organism<\/a><\/li>\n      <li><a href=\"#a-retenir\">Key takeaways<\/a><\/li>\n      <li><a href=\"#questions-frequentes\">Frequently asked questions<\/a><\/li>\n      <li><a href=\"#vous-souhaitez-comprendre-votre-propre-situation\">Want to understand your own situation?<\/a><\/li>\n      <li><a href=\"#references-scientifiques\">Scientific references<\/a><\/li>\n  <\/ul>\n<\/nav>\n\n<h2 id=\"pourquoi-cet-article\">Why this article?<\/h2>\n\n<p>\n  For a long time, the placebo effect was regarded as a purely psychological phenomenon. When a person\u2019s\n  pain decreased after receiving an inactive substance, many saw it as proof that \u201cit was all\n  in their head.\u201d\n<\/p>\n\n<p>\n  Today, however, neuroscience tells a different story. Thanks to brain imaging, it is now\n  possible to observe the brain while a person is experiencing pain or receiving a treatment. This research has\n  revealed an unexpected finding: in people who respond to a placebo, some of the same brain\n  regions activated by an actual opioid analgesic treatment are also engaged. This is\n  particularly the case for the rostral anterior cingulate cortex, whose activity covaries with that of the brainstem in a\n  similar way during opioid analgesia and placebo analgesia\n  <span class=\"bp-inline-ref\">(Petrovic et&nbsp;al., 2002)<\/span>. A second study showed that placebo analgesia\n  is accompanied by decreased activity in pain-sensitive regions (thalamus, insula, anterior\n  cingulate cortex). It is also accompanied by increased prefrontal activity during the anticipation of pain\n  <span class=\"bp-inline-ref\">(Wager et&nbsp;al., 2004)<\/span>. A meta-analysis of 25 imaging studies\n  subsequently confirmed the consistency of these findings across the literature\n  <span class=\"bp-inline-ref\">(Atlas &amp; Wager, 2014)<\/span>.\n<\/p>\n\n<p>\n  The placebo effect is therefore neither an illusion of pain nor imaginary relief: it corresponds to\n  measurable changes in the way the nervous system processes and modulates pain. This discovery has thus profoundly changed our understanding of the brain. Indeed, the brain is\n  not merely an observer of the events occurring in the body: it actively participates in their\n  regulation.\n<\/p>\n\n<div class=\"bp-figure\">\n  <img decoding=\"async\" src=\"https:\/\/blueportance.com\/wp-content\/uploads\/XII.1.-Brain-networks-engaged-by-a-treatment-and-by-a-placebo.png\" alt=\"Partial overlap between brain networks activated by analgesic treatment and placebo analgesia.\" loading=\"lazy\">\n<\/div>\n<p class=\"bp-figure-caption\">\n  <strong>The brain networks engaged by a treatment and by a placebo.<\/strong> Brain imaging\n  shows that the pain-modulation activity engaged by a placebo partly overlaps with brain systems engaged during some forms of analgesia, notably opioid analgesia, illustrating the existence of endogenous biological mechanisms of pain control.\n<\/p>\n\n<h2 id=\"le-cerveau-ne-subit-pas-il-anticipe\">The brain is not passive: it anticipates<\/h2>\n\n<p>\n  The previous articles in this guide have shown that pain results from the interaction between tissues and the\n  nervous system. It also involves the body\u2019s adaptive capacities and\n  <a href=\"https:\/\/blueportance.com\/en\/knowledge-base\/expert-guides\/understanding-pain\/adaptive-pain-loops\/\">adaptive loops<\/a>\n  that can gradually become self-sustaining. The brain thus helps coordinate this whole, in\n  constant interaction with the information coming from the body and the environment.\n<\/p>\n\n<p>\n  Indeed, its role is not limited to receiving information from the body. It continuously\n  interprets sensory signals, compares them with past experiences, assesses the context, and builds a\n  prediction of what is likely to happen. This capacity for anticipation is today one of the\n  major models in contemporary neuroscience, often referred to as predictive coding. In these models,\n  the brain is described as continuously generating predictions and adjusting them based on the sensory\n  information it receives\n  <span class=\"bp-inline-ref\">(Friston, 2010; Clark, 2016)<\/span>. Normally, this capacity allows the body to react\n  quickly to danger, adapt behavior, and optimize its responses. Pain is also\n  part of this adaptive logic: it too can be anticipated, amplified, or dampened depending on what the\n  brain predicts about the context.\n<\/p>\n\n<h2 id=\"un-veritable-systeme-biologique-de-modulation\">A genuine biological modulation system<\/h2>\n\n<p>\n  When the brain judges that a situation is better under control, it can activate its own\n  regulatory systems. This is the case, for example, when a treatment is administered, when a trusted\n  person steps in, or when the context simply becomes reassuring. These mechanisms are now well identified. They notably involve the prefrontal\n  cortex, which contributes to expectations and to the appraisal of context, as well as the anterior cingulate cortex, which is involved\n  in pain control. They also rely on the periaqueductal gray, a center for modulating pain\n  pathways. Finally, there are the endogenous opioid systems, which can reduce the transmission of nociceptive\n  signals.\n<\/p>\n\n<p>\n  Moreover, these networks belong to the descending pain modulation system, which is now extensively documented\n  <span class=\"bp-inline-ref\">(Fields, 2004; Tracey &amp; Mantyh, 2007)<\/span>. One study showed that\n  administering naloxone, an opioid antagonist, reduces both the behavioral effect of the placebo and\n  the associated brain responses. This reduction extends all the way to brainstem structures involved in descending\n  pain modulation \u2014 the periaqueductal gray and the rostral ventromedial medulla (RVM)\n  <span class=\"bp-inline-ref\">(Eippert et&nbsp;al., 2009)<\/span>. This study is particularly compelling: it\n  shows that placebo-induced activation extends all the way to the structures that directly modulate the\n  transmission of the pain signal. The placebo therefore does not create a special mechanism: it engages\n  biological systems that already exist in the brain, and that partly overlap with those engaged during opioid analgesia.\n<\/p>\n\n<div class=\"bp-figure\">\n  <img decoding=\"async\" src=\"https:\/\/blueportance.com\/wp-content\/uploads\/XII.2.-The-descending-pain-modulation-system.png\" alt=\"Descending pain modulation pathway linking the prefrontal cortex, anterior cingulate cortex, periaqueductal gray, RVM and spinal cord.\" loading=\"lazy\">\n<\/div>\n<p class=\"bp-figure-caption\">\n  <strong>The descending pain modulation system.<\/strong> The descending modulation pathways\n  allow the brain to reduce or amplify the transmission of nociceptive signals depending on the context and\n  the body\u2019s needs.\n<\/p>\n\n<h2 id=\"le-placebo-ne-remplace-pas-un-traitement\">A placebo does not replace a treatment<\/h2>\n\n<p>\n  This discovery does not mean, however, that a placebo can heal a fracture, free a compressed nerve,\n  clear up an infection, or treat cancer. Lesions remain. Mechanical stresses persist.\n  Inflammatory processes follow their own course.\n<\/p>\n\n<p>\n  In fact, the placebo acts elsewhere: it mainly changes the way the nervous system processes and modulates\n  pain-related information. In other words, it influences the perception and regulation of pain, without\n  necessarily removing its cause. The authoritative reviews on the subject emphasize this point: the placebo\n  mainly modulates the perception of pain. It does not directly treat the cause of tissue damage\n  <span class=\"bp-inline-ref\">(Benedetti, 2014; Colloca &amp; Barsky, 2020)<\/span>.\n<\/p>\n\n<p>\n  This distinction is essential. It explains why an effective treatment should always\n  seek to correct the mechanism responsible for the pain \u2014 as do the\n  <a href=\"https:\/\/blueportance.com\/en\/knowledge-base\/expert-guides\/understanding-pain\/restoring-adaptability-chronic-pain\/\">main families of treatment<\/a>\n  already presented in this guide. At the same time, however, it is important to take into account the brain\u2019s natural capacity to participate in the\n  recovery process.\n<\/p>\n\n<h2 id=\"l-effet-inverse-existe-aussi-le-nocebo\">The opposite effect also exists: the nocebo effect<\/h2>\n\n<p>\n  If positive expectations can reduce pain, negative expectations can produce the opposite effect.\n  Fear, uncertainty, worrying explanations, or unfavorable past experiences can increase the\n  vigilance of the nervous system and amplify the perception of pain: this is known as the nocebo effect.\n<\/p>\n\n<p>\n  Here again, however, this is not an imaginary phenomenon. A landmark study showed that worrying words\n  spoken before a painful procedure are enough to activate identifiable biological networks and to increase the\n  sensitivity of the nervous system\n  <span class=\"bp-inline-ref\">(Benedetti et&nbsp;al., 2007)<\/span>. In other words, negative expectations are not mere states of mind: they have a\n  measurable physiological expression. A review on the clinical relevance of the nocebo effect\n  also points out that the way possible side effects are presented can contribute to increasing their\n  perception or reporting in some people\n  <span class=\"bp-inline-ref\">(Colloca &amp; Miller, 2011)<\/span>. The therapeutic context thus becomes a\n  genuine biological actor in care, in either direction.\n<\/p>\n\n<div class=\"bp-figure\">\n  <img decoding=\"async\" src=\"https:\/\/blueportance.com\/wp-content\/uploads\/XII.3.-Placebo-and-nocebo_two-opposite-responses-of-the-same-predictive-brain.png\" alt=\"Comparison showing how positive and negative expectations can respectively reduce or amplify perceived pain.\" loading=\"lazy\">\n<\/div>\n<p class=\"bp-figure-caption\">\n  <strong>Placebo and nocebo: two opposite responses of the same predictive brain.<\/strong> The predictive\n  brain can mobilize the natural pain-modulation mechanisms (placebo) or, conversely, heighten\n  vigilance and amplify pain (nocebo), depending on the context and expectations.\n<\/p>\n\n<table aria-label=\"Placebo and nocebo compared\">\n  <thead>\n    <tr><th>Criterion<\/th><th>Placebo effect<\/th><th>Nocebo effect<\/th><\/tr>\n  <\/thead>\n  <tbody>\n    <tr><td><strong>Trigger<\/strong><\/td><td>Positive expectation, confidence in the treatment, reassuring context<\/td><td>Negative expectation, fear, worrying information, unfavorable past experience<\/td><\/tr>\n    <tr><td><strong>Central mechanism<\/strong><\/td><td>Activation of the descending modulation system (prefrontal cortex, cingulate cortex, PAG, endogenous opioids)<\/td><td>Hypervigilance of the nervous system, sensitization of pain perception<\/td><\/tr>\n    <tr><td><strong>Effect on perceived pain<\/strong><\/td><td>Decrease<\/td><td>Amplification<\/td><\/tr>\n    <tr><td><strong>What it does not change<\/strong><\/td><td>The underlying lesion or mechanical stress<\/td><td>The underlying lesion or mechanical stress<\/td><\/tr>\n  <\/tbody>\n<\/table>\n\n<h2 id=\"une-nouvelle-lecture-du-soin\">A new way of understanding care<\/h2>\n\n<p>\n  This view thus naturally aligns with all the mechanisms described in this guide. Chronic pain often\n  results from the interaction of several adaptive loops: persistent mechanical stresses,\n  sensitization of the nervous system, behavioral changes, gradual loss of physical capacity, and\n  disruption of many biological mechanisms. Treatments seek to act on these different components \u2014\n  but they also act within a human context.\n<\/p>\n\n<p>\n  The quality of the information given to the person, their understanding of their pain, and their confidence in the proposed\n  treatment all contribute to mobilizing the body\u2019s natural regulatory mechanisms. The same applies to the consistency of the explanations, the feeling of gradually regaining control of the situation, and\n  the positive experience of the first improvements. Pain education \u2014 explaining to a person what is actually happening in their body \u2014\n  is part of this logic. It does not claim to demonstrate a specific placebo mechanism, but it aims to\n  act on understanding and expectations, two levers that influence the perception of pain\n  <span class=\"bp-inline-ref\">(Moseley &amp; Butler, 2015)<\/span>. Far from being opposed to biological\n  treatments, these dimensions accompany them and can enhance their effectiveness.\n<\/p>\n\n<div class=\"bp-model\">\n  <h2 id=\"le-mot-de-la-fin-une-medecine-qui-mobilise-tout-le-vivant\">The final word: a medicine that engages the whole living organism<\/h2>\n  <p>\n    For a long time, \u201creal\u201d treatments and the placebo effect were presented as two opposing phenomena.\n    In reality, neuroscience now shows that this opposition is largely artificial. A treatment acts through\n    its own properties \u2014 mechanical, pharmacological, surgical, or rehabilitative. But it also acts through the\n    way the brain mobilizes its own capacities for adaptation and modulation.\n  <\/p>\n  <p>\n    In other words, providing care is not only about correcting a lesion or prescribing a treatment. It is\n    also about creating the conditions that allow the body to fully mobilize its biological resources \u2014 the same\n    logic as the one developed in\n    <a href=\"https:\/\/blueportance.com\/en\/knowledge-base\/expert-guides\/understanding-pain\/restoring-adaptability-chronic-pain\/\">the previous article<\/a>\n    around the adaptive system (C7).\n  <\/p>\n  <p>\n    This brings the guiding thread of this guide full circle. From tissues to the brain, from mechanical stresses to\n    prediction mechanisms, from sensitization to functional recovery: the same idea runs\n    through all of these chapters. The living organism is an adaptive system. Understanding pain ultimately comes down\n    to understanding how this adaptive capacity can be exceeded, then gradually restored.\n  <\/p>\n<\/div>\n<div class=\"bp-figure\">\n  <img decoding=\"async\" src=\"https:\/\/blueportance.com\/wp-content\/uploads\/XII.4.-From-tissue-to-brain_the-living-organism-as-an-adaptive-system.png\" alt=\"Summary diagram linking tissues, nervous system, brain and adaptive capacities in the understanding of pain.\" loading=\"lazy\">\n<\/div>\n<p class=\"bp-figure-caption\">\n  <strong>From tissue to brain: the living organism as an adaptive system.<\/strong> In summary, the various\n  mechanisms presented in this guide converge on a single idea. Pain results\n  from the interaction between tissues, the nervous system, and the brain, within a single adaptive system.\n<\/p>\n\n<h3>The studies that shaped the current understanding of placebo<\/h3>\n\n<div class=\"bp-definition\">\n  <strong class=\"bp-def-source\">Further reading \u2014 The foundational studies<\/strong>\n  <p>\n    This interpretation of the placebo effect is not an isolated hypothesis. It is based on research published in\n    <em>Science<\/em>, <em>Neuron<\/em>, <em>Nature Reviews Neuroscience<\/em>, and the <em>New England Journal of\n    Medicine<\/em>. Five publications in particular have shaped the current understanding of the phenomenon. Petrovic\n    et&nbsp;al. (2002) were the first to show, using imaging, the overlap between opioid\n    analgesia and placebo analgesia. Wager et&nbsp;al. (2004) then documented the changes in brain\n    activity associated with the anticipation and experience of pain under placebo. Eippert et&nbsp;al.\n    (2009) also established the role of the endogenous opioid system all the way down to the brainstem. Atlas &amp; Wager\n    (2014), for their part, confirmed through meta-analysis the consistency of these findings across the literature. Finally, Benedetti\n    (2014) published the reference work that is now considered authoritative on the subject.\n  <\/p>\n<\/div>\n\n<div class=\"bp-takeaway\">\n  <h2 id=\"a-retenir\">Key takeaways<\/h2>\n  <ul>\n    <li>The placebo effect is neither imaginary nor proof that the pain was not real: brain imaging shows that it can mobilize real biological pain-modulation mechanisms, particularly in people who respond to it, which partly overlap with brain systems engaged during some forms of analgesia.<\/li>\n    <li>The brain does not merely receive signals from the body: it continuously anticipates, drawing on context and past experiences.<\/li>\n    <li>This modulation system involves the prefrontal cortex, the anterior cingulate cortex, the periaqueductal gray, and the endogenous opioid systems.<\/li>\n    <li>A placebo does not repair any lesion and does not replace any treatment: it changes the perception and regulation of pain, not its cause.<\/li>\n    <li>The nocebo effect is the negative counterpart of the placebo effect: negative expectations can amplify perceived pain, through anticipation and modulation mechanisms that are partly shared.<\/li>\n    <li>The quality of information and of the therapeutic context is, in this respect, a genuine biological lever in care \u2014 one that brings the guiding thread of this guide full circle: the living organism as an adaptive system.<\/li>\n  <\/ul>\n<\/div>\n\n<section class=\"bp-faq\">\n  <h2 id=\"questions-frequentes\">Frequently asked questions<\/h2>\n\n  <details>\n    <summary>Does the placebo effect mean the pain was not real?<\/summary>\n    <div class=\"faq-content\">\n      No. Imaging studies show that the placebo effect can mobilize real brain mechanisms of\n      pain modulation, particularly in people who respond to it, which partly overlap with brain systems engaged during some forms of analgesia. The initial pain was real, and its reduction under placebo is just as real.\n    <\/div>\n  <\/details>\n\n  <details>\n    <summary>Can a treatment be replaced with a placebo?<\/summary>\n    <div class=\"faq-content\">\n      No. A placebo changes the way the nervous system perceives and modulates pain, but it does not correct\n      a lesion, a mechanical stress, or an inflammatory process. An effective treatment should always\n      target the mechanism responsible for the pain.\n    <\/div>\n  <\/details>\n\n  <details>\n    <summary>What is the nocebo effect?<\/summary>\n    <div class=\"faq-content\">\n      It is the opposite of the placebo effect: negative expectations, fear, or worrying information can\n      activate biological mechanisms that amplify the perception of pain, through anticipation and modulation\n      mechanisms that are partly shared with those of the placebo effect, but whose biological mediators and\n      networks involved are not strictly identical.\n    <\/div>\n  <\/details>\n\n  <details>\n    <summary>Why does the care context play a role in how effective a treatment is?<\/summary>\n    <div class=\"faq-content\">\n      Because the brain continuously assesses the context to anticipate what will happen. Confidence in\n      the treatment, the quality of the information received, and a sense of control can therefore mobilize the body\u2019s natural\n      pain-modulation systems, as a complement to \u2014 never a replacement for \u2014 the treatment itself.\n    <\/div>\n  <\/details>\n<\/section>\n\n<div class=\"bp-cta\">\n  <h2 id=\"vous-souhaitez-comprendre-votre-propre-situation\">Want to understand your own situation?<\/h2>\n  <p>\n    The mechanisms presented in this guide can help you better understand why pain persists, but they do not\n    replace an individual assessment.\n  <\/p>\n  <a href=\"https:\/\/blueportance.com\/en\/personalized-pain-analysis\/\">Analyze my situation \u2192<\/a>\n<\/div>\n\n<p class=\"bp-note\">\n  <strong>Note:<\/strong> this content presents general knowledge drawn from neuroscience and does not\n  constitute a diagnosis or a prescription. It should not be interpreted as an invitation to replace a\n  prescribed treatment with a placebo: any treatment decision should be made with a healthcare\n  professional.\n<\/p>\n\n<section class=\"bp-references\">\n  <h2 id=\"references-scientifiques\">Scientific references<\/h2>\n\n  <h3>Neuroscientific basis of the placebo effect<\/h3>\n  <ol>\n    <li>Petrovic P, Kalso E, Petersson KM, Ingvar M. <em>Placebo and opioid analgesia\u2014imaging a shared neuronal network.<\/em> Science. 2002;295(5560):1737\u20131740.<\/li>\n    <li>Wager TD, Rilling JK, Smith EE, et al. <em>Placebo-induced changes in FMRI in the anticipation and experience of pain.<\/em> Science. 2004;303(5661):1162\u20131167.<\/li>\n    <li>Eippert F, Bingel U, Schoell E, et al. <em>Activation of the opioidergic descending pain control system underlies placebo analgesia.<\/em> Neuron. 2009;63(4):533\u2013543.<\/li>\n    <li>Atlas LY, Wager TD. <em>A meta-analysis of brain mechanisms of placebo analgesia: consistent findings and unanswered questions.<\/em> In: Handbook of Experimental Pharmacology, vol. 225. Springer; 2014:37\u201369.<\/li>\n  <\/ol>\n\n  <h3>The predictive brain<\/h3>\n  <ol start=\"5\">\n    <li>Friston K. <em>The free-energy principle: a unified brain theory?<\/em> Nature Reviews Neuroscience. 2010;11:127\u2013138.<\/li>\n    <li>Clark A. <em>Surfing Uncertainty: Prediction, Action, and the Embodied Mind.<\/em> Oxford University Press; 2016.<\/li>\n  <\/ol>\n\n  <h3>Descending pain modulation system<\/h3>\n  <ol start=\"7\">\n    <li>Fields HL. <em>State-dependent opioid control of pain.<\/em> Nature Reviews Neuroscience. 2004;5:565\u2013575.<\/li>\n    <li>Tracey I, Mantyh PW. <em>The cerebral signature for pain perception and its modulation.<\/em> Neuron. 2007;55(3):377\u2013391.<\/li>\n  <\/ol>\n\n  <h3>Placebo, nocebo, and clinical practice<\/h3>\n  <ol start=\"9\">\n    <li>Benedetti F. <em>Placebo Effects: Understanding the Mechanisms in Health and Disease.<\/em> 2nd ed. Oxford University Press; 2014.<\/li>\n    <li>Colloca L, Barsky AJ. <em>Placebo and nocebo effects.<\/em> New England Journal of Medicine. 2020;382(6):554\u2013561.<\/li>\n    <li>Benedetti F, Lanotte M, Lopiano L, Colloca L. <em>When words are painful: unraveling the mechanisms of the nocebo effect.<\/em> Neuroscience. 2007;147(2):260\u2013271.<\/li>\n    <li>Colloca L, Miller FG. <em>The nocebo effect and its relevance for clinical practice.<\/em> Psychosomatic Medicine. 2011;73(7):598\u2013603.<\/li>\n  <\/ol>\n\n  <h3>Pain education<\/h3>\n  <ol start=\"13\">\n    <li>Moseley GL, Butler DS. <em>Fifteen Years of Explaining Pain: The Past, Present, and Future.<\/em> Journal of Pain. 2015;16(9):807\u2013813.<\/li>\n  <\/ol>\n<\/section>\n\n<p class=\"bp-copyright\">\n  \u00a9 Gil Ayache. The concepts, diagrams, terminology, and principles presented on this page constitute a work protected by copyright. They are made available to Blue Portance under an intellectual property license agreement, without transfer of economic rights or of authorship.\n<\/p>\n\n\n","protected":false},"excerpt":{"rendered":"<p>Blue Portance \u2192 Knowledge Base \u2192 Understanding Pain \u2192 Placebo and Nocebo Effects Blue Portance Expert Guides Understanding Pain The biological, mechanical, and neurophysiological mechanisms of pain. This article is part of the Expert Guide \u201cUnderstanding Pain\u201d. Guide conclusion \u2014 Blue Portance Knowledge Base When the Brain Can Take Back Control: Understanding the Placebo Effect [&#8230;]\n","protected":false},"author":6,"featured_media":0,"parent":8012,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"_acf_changed":false,"_yoast_wpseo_title":"Placebo and Nocebo Effects Explained | Blue Portance","_yoast_wpseo_metadesc":"The placebo effect without misconceptions: placebo and nocebo as two responses of the same predictive brain.","footnotes":""},"pathologie_secondaire":[],"effet_positif":[],"class_list":["post-8083","page","type-page","status-publish","hentry"],"acf":[],"yoast_head":"<!-- This site is optimized with the Yoast SEO Premium plugin v28.7 (Yoast SEO v28.8) - https:\/\/yoast.com\/product\/yoast-seo-premium-wordpress\/ -->\n<title>Placebo and Nocebo Effects Explained | Blue Portance<\/title>\n<meta name=\"description\" content=\"The placebo effect without misconceptions: placebo and nocebo as 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