The Meaning Response, "Placebo," and Methods

Abstract

In 2002, Dan Moerman outlined three candidate explanations for the "placebo response": the "conditioned stimulus-response," Irving Kirsch's "response-expectancy" explanation, and the "meaning response." The meaning response, Moerman argued, was the only one of the three candidate explanations that could cover all the data, gained from decades of RCTs and centuries of historical record. Moerman went so far as to propose replacing the term "placebo effect/response" with the term "meaning response," because people are not responding to placebos, since there is nothing to respond to; people are responding to meanings. There is evidence of medically significant meaning responses where there is no evidence for conditioning. Similarly, there is evidence for such responses where those subject to them lack the knowledge-epistemic capital-required to form the beliefs which might constitute an expectation. Something else, neither conditioning nor propositional attitudes, explained placebo responses, and Moerman proposed the meaning response. While the authors consider the meaning response to avoid the pitfalls of conditioning and response-expectancy, it has been subject to criticism. The criticisms have focused on what is seen as the explanation falling foul of the naturalistic demand and not fitting

The “placebo” paradox and the emotion paradox: Challenges to psychological explanation

“…Second, the epistemic deficit. There are cases of “placebo responses” where the knowledge—the epistemic capital—required to form the relevant expectation is absent (see Hutchinson & Moerman, 2018). If an explanation invokes mental representations or mental models of the world, then for these representations or models to have content, the mind needs, at the minimum, access to the information that serves as the building blocks for that content.…”

Significance of Participants’ Expectations in Managing the Placebo Effect in Antidepressant Research

“…As stated previously, the placebo-expectation paradigm has sufficient empirical neurobiological foundation and emphasizes the human mind as a “prediction machine.” When sufficiently broadly defined, expectations may represent a common final pathway of the placebo effect (4, 7). However, other placebo effect conceptualizations put more emphasis on the relational and broader contextual determinants, highlighting silent priors and underlying unconscious processes (1, 5, 6, 16). In alternative frameworks, the placebo effect either refers to dimensions other than expectations or is considered redundant in precisely describing phenomena driving the therapeutic response (6, 16–18).…”

“…However, other placebo effect conceptualizations put more emphasis on the relational and broader contextual determinants, highlighting silent priors and underlying unconscious processes (1, 5, 6, 16). In alternative frameworks, the placebo effect either refers to dimensions other than expectations or is considered redundant in precisely describing phenomena driving the therapeutic response (6, 16–18). The relationship between patients and practitioners has been considered an essential part of the placebo effect, representing the process of interpersonal healing (18, 19).…”

“…More recently, the placebo effect has been described as an outcome of persuasive communication, where the practitioner characteristics exert significant influence on the placebo effect (21). Additionally, emphasis on various contextual features of the treatment situation that have profound therapeutic effects brought out the concept of “contextual healing,” with the “meaning response” representing an underlying mechanism (16, 18, 22). Mindsets and different forms of social learning have also been singled out as crucial in understanding how broader social context is shaping the placebo effect (23).…”

Optimizing Expectations via Mobile Apps: A New Approach for Examining and Enhancing Placebo Effects

“…As a result of these problems, there have been various attempts to make a case for abandoning the concept of placebo effect (15) and to propose new concepts [e.g., “context effects” (12), “meaning responses” (16)]. Because the concept of placebo is deeply entrenched in the literature, proposed alternative labels and concepts have not been adopted.…”