Learning by observing: a systematic exploration of modulatory factors and the impact of observationally induced placebo and nocebo effects on treatment outcomes
IntroductionObservational learning (OL) refers to learning through observing other people’s behavior. OL has been suggested as an effective and simple tool to evoke treatment expectations and corresponding placebo and nocebo effects. However, the exact mechanisms by which OL shapes treatment outcome...
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| Format: | Article |
| Language: | English |
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Frontiers Media S.A.
2024-04-01
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| Series: | Frontiers in Psychology |
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| Online Access: | https://www.frontiersin.org/articles/10.3389/fpsyg.2024.1293975/full |
| _version_ | 1797201539866034176 |
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| author | Helena Klauß Angelika Kunkel Diana Müßgens Jan Haaker Ulrike Bingel |
| author_facet | Helena Klauß Angelika Kunkel Diana Müßgens Jan Haaker Ulrike Bingel |
| author_sort | Helena Klauß |
| collection | DOAJ |
| description | IntroductionObservational learning (OL) refers to learning through observing other people’s behavior. OL has been suggested as an effective and simple tool to evoke treatment expectations and corresponding placebo and nocebo effects. However, the exact mechanisms by which OL shapes treatment outcomes, its moderating factors and possible areas of application remain unclear. We thus reviewed the existing literature with two different literature searches to answer the following questions: Which influencing factors contribute to OL-induced placebo and nocebo effects (in healthy volunteers and patients) and how large are these effects (search 1)? In which medical fields has OL been used so far to modulate treatment expectancy and treatment outcomes in patients, their caregivers, and at-risk groups (search 2)? We also aimed to explore whether and how the assessment of treatment expectations has been incorporated.MethodsWe conducted two independent and comprehensive systematic literature searches, both carried out on September 20, 2022.ResultsWe identified 21 studies that investigated OL-mediated placebo and nocebo effects for pain and itch, the (placebo) efficacy of sham treatment on anxiety, and the (nocebo) induction of medication side effects (search 1). Studies showed that OL can efficiently induce placebo and nocebo effects across different presentation modes, with medium effect sizes on average: placebo effects, d = 0.79 (range: d = −0.36–1.58), nocebo effects, d = 0.61 (range: d = 0.04–1.5). Although several moderating factors have been investigated, their contribution to OL-induced effects remains unclear because of inconsistent results. Treatment expectation was assessed in only four studies. Regarding medical applications of OL (search 2), we found 12 studies. They showed that OL was effectively applied in preventive, therapeutic and rehabilitative interventions and that it was mainly used in the field of psychosomatics.DiscussionOL effects on treatment outcomes can be both positive and negative. Future research should investigate which individuals would benefit most from OL and how OL can be implemented most effectively to induce placebo and avoid nocebo effects in clinical settings.Systematic review registrationThis work was preregistered at the Center for Open Science as open-ended registration (doi: 10.17605/OSF.IO/FVHKE). The protocol can be found here: https://archive.org/details/osf-registrations-fvhke-v1. |
| first_indexed | 2024-04-24T07:49:09Z |
| format | Article |
| id | doaj.art-a17f9140d8014b98b81266a38e3f4507 |
| institution | Directory Open Access Journal |
| issn | 1664-1078 |
| language | English |
| last_indexed | 2024-04-24T07:49:09Z |
| publishDate | 2024-04-01 |
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| series | Frontiers in Psychology |
| spelling | doaj.art-a17f9140d8014b98b81266a38e3f45072024-04-18T15:25:53ZengFrontiers Media S.A.Frontiers in Psychology1664-10782024-04-011510.3389/fpsyg.2024.12939751293975Learning by observing: a systematic exploration of modulatory factors and the impact of observationally induced placebo and nocebo effects on treatment outcomesHelena Klauß0Angelika Kunkel1Diana Müßgens2Jan Haaker3Ulrike Bingel4Department of Neurology, Center for Translational Neuro-and Behavioral Sciences (C-TNBS), University Medicine Essen, University of Duisburg-Essen, Essen, GermanyDepartment of Neurology, Center for Translational Neuro-and Behavioral Sciences (C-TNBS), University Medicine Essen, University of Duisburg-Essen, Essen, GermanyDepartment of Neurology, Center for Translational Neuro-and Behavioral Sciences (C-TNBS), University Medicine Essen, University of Duisburg-Essen, Essen, GermanyDepartment of Systems Neuroscience, University Medical Center Hamburg-Eppendorf, Hamburg, GermanyDepartment of Neurology, Center for Translational Neuro-and Behavioral Sciences (C-TNBS), University Medicine Essen, University of Duisburg-Essen, Essen, GermanyIntroductionObservational learning (OL) refers to learning through observing other people’s behavior. OL has been suggested as an effective and simple tool to evoke treatment expectations and corresponding placebo and nocebo effects. However, the exact mechanisms by which OL shapes treatment outcomes, its moderating factors and possible areas of application remain unclear. We thus reviewed the existing literature with two different literature searches to answer the following questions: Which influencing factors contribute to OL-induced placebo and nocebo effects (in healthy volunteers and patients) and how large are these effects (search 1)? In which medical fields has OL been used so far to modulate treatment expectancy and treatment outcomes in patients, their caregivers, and at-risk groups (search 2)? We also aimed to explore whether and how the assessment of treatment expectations has been incorporated.MethodsWe conducted two independent and comprehensive systematic literature searches, both carried out on September 20, 2022.ResultsWe identified 21 studies that investigated OL-mediated placebo and nocebo effects for pain and itch, the (placebo) efficacy of sham treatment on anxiety, and the (nocebo) induction of medication side effects (search 1). Studies showed that OL can efficiently induce placebo and nocebo effects across different presentation modes, with medium effect sizes on average: placebo effects, d = 0.79 (range: d = −0.36–1.58), nocebo effects, d = 0.61 (range: d = 0.04–1.5). Although several moderating factors have been investigated, their contribution to OL-induced effects remains unclear because of inconsistent results. Treatment expectation was assessed in only four studies. Regarding medical applications of OL (search 2), we found 12 studies. They showed that OL was effectively applied in preventive, therapeutic and rehabilitative interventions and that it was mainly used in the field of psychosomatics.DiscussionOL effects on treatment outcomes can be both positive and negative. Future research should investigate which individuals would benefit most from OL and how OL can be implemented most effectively to induce placebo and avoid nocebo effects in clinical settings.Systematic review registrationThis work was preregistered at the Center for Open Science as open-ended registration (doi: 10.17605/OSF.IO/FVHKE). The protocol can be found here: https://archive.org/details/osf-registrations-fvhke-v1.https://www.frontiersin.org/articles/10.3389/fpsyg.2024.1293975/fullobservational learningsocial learningplacebo effectnocebo effectexpectationtreatment outcomes |
| spellingShingle | Helena Klauß Angelika Kunkel Diana Müßgens Jan Haaker Ulrike Bingel Learning by observing: a systematic exploration of modulatory factors and the impact of observationally induced placebo and nocebo effects on treatment outcomes Frontiers in Psychology observational learning social learning placebo effect nocebo effect expectation treatment outcomes |
| title | Learning by observing: a systematic exploration of modulatory factors and the impact of observationally induced placebo and nocebo effects on treatment outcomes |
| title_full | Learning by observing: a systematic exploration of modulatory factors and the impact of observationally induced placebo and nocebo effects on treatment outcomes |
| title_fullStr | Learning by observing: a systematic exploration of modulatory factors and the impact of observationally induced placebo and nocebo effects on treatment outcomes |
| title_full_unstemmed | Learning by observing: a systematic exploration of modulatory factors and the impact of observationally induced placebo and nocebo effects on treatment outcomes |
| title_short | Learning by observing: a systematic exploration of modulatory factors and the impact of observationally induced placebo and nocebo effects on treatment outcomes |
| title_sort | learning by observing a systematic exploration of modulatory factors and the impact of observationally induced placebo and nocebo effects on treatment outcomes |
| topic | observational learning social learning placebo effect nocebo effect expectation treatment outcomes |
| url | https://www.frontiersin.org/articles/10.3389/fpsyg.2024.1293975/full |
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