The Placebo Effect: a Connection Between Body and Mind

Author: Katherine Bruner

In the late 18th century, American doctor Elisha Perkins introduced an unconventional treatment: tear shaped metal rods otherwise called Perkins tractors; he claimed they conducted “pathogenic electric fluid” away from the body. This treatment reached Britain in 1799 and became popular in Bath [1]. One physician, Dr. John Haygarth, who was skeptical of this claim devised a trial using wooden tractors identical to Perkins’ metal ones [2]. The final results were that 4 of the 5 patients reported feeling pain relief from both the wooden and metal tractors. This intriguing episode exemplifies one of the first demonstrations of the placebo effect, a phenomenon where non-existent or fake treatments stimulate improvements in individuals [3].

While this effect is now widely recognized, its precise mechanisms remain somewhat mysterious. Research has demonstrated that the effect is a result of the brain triggering psychological responses, such as the release of hormones and neurotransmitters; all of which trigger the immune response, often resulting in pain relief for patients [4] . 

Although the exact pathway of the placebo effect is unknown, it is known that lots of mechanisms play a role. Notably, patients’ expectations regarding the treatment plays a significant role as a mechanism of the placebo effect.. When patients are informed that a certain medication should produce specific symptoms while being examined in a doctor’s office (a professional setting), it can manipulate their perceptions [5]. Additionally, conditioning can influence results, as being repeatedly told that something is good or bad can lead to a premature opinion that overrides the actual response [5].

The neurobiological mechanism involves more of the brain’s actual response to these treatments. The Neurochemical Cascade is the brain’s response to a placebo involving neurotransmitters such as serotonin and dopamine; these chemicals contribute to pain modulation, mood regulation, and overall well-being. When the brain anticipates relief, it activates these pathways, leading to tangible improvements [5].

A common example is seen in clinical trials for insomnia where randomized placebo-controlled trials of insomnia found that patients given the placebo had improved, demonstrating that insomnia can be responsive to the placebo effect. This is consistent with the aforementioned mechanisms, which elicit the positive response through the release of hormones, conditioning, or rituals patients undergo during the studies, such as taking a pill or visiting the doctor [6].

Ethics

There remains lots to learn about the placebo effect and its ethics, contributing to debate on whether or not doctors should prescribe placebo pills [7]. Since it is not yet fully understood, doctors and other medical professionals need to be careful when prescribing it so as to not lose the trust of the patients or negatively impact their health. However, there is a possible solution: the use of an “open-label placebo.” An open-label placebo is a phenomenon that occurs when the patient knows the placebo is a placebo. Even with the patient’s knowledge, studies have shown that there have been improvements in patient health. The use of this solution could eliminate the ethical dilemma doctors face, while continuing to help patients [8].

Conclusion

The placebo effect holds immense potential in medical treatment, particularly in symptom relief and pain management. Although its effects can be quite powerful, the placebo effect is not entirely understood; therefore, its limitations in patient use highlight the need for further research. It is also important to remember that the placebo effect does indeed have “physical” limitations. This is why it can only help relieve some symptoms, primarily used for pain management and other situations like insomnia [2]. A stronger and more comprehensive understanding of the placebo effect could lead to improved patient outcomes in the future.

Editors

Almokhtar Albakoosh, Rawad Al-Aarg, Majd Al-Aarg (Editor-in-Chief)

Designer

Web design by Majd-Alarg

Additional Credits

Photo by Anna Shvets

References

1. McDonald A. From the history of Medicine Artifacts Collection: Perkins’s tractors [Internet]. 2017 [cited 2024 Sept 4]. Available from: https://blogs.library.duke.edu/rubenstein/2017/01/26/perkins-tractors/ 
2. Lewine H. The power of the placebo effect [Internet]. 2024 [cited 2024 Sept 4]. Available from: https://www.health.harvard.edu/mental-health/the-power-of-the-placebo-effect 
3.  Jiang B, He D, Guo Z, Gao Z. Dynamic features of placebo effects addressing persistent … [Internet]. 2020 [cited 2024 Sept 4]. Available from: https://onlinelibrary.wiley.com/doi/abs/10.1111/jsr.12997 
4.  Hodo TW, de Aquino MTP, Shimamoto A, Shanker A. Critical neurotransmitters in the neuroimmune network [Internet]. U.S. National Library of Medicine; 2020 [cited 2024 Sept 4]. Available from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7472989/ 
5. Finniss DG, Kaptchuk TJ, Miller F, Benedetti F. Biological, clinical, and ethical advances of placebo effects [Internet]. U.S. National Library of Medicine; 2010 [cited 2024 Sept 4]. Available from: https://pubmed.ncbi.nlm.nih.gov/20171404/ 
6.  Colagiuri B, Sharpe L, Ambarchi Z, Glozier N, Bartlett D, Costa DSJ, et al. Open-label placebo for insomnia (opin): Study protocol for a cohort multiple randomised controlled trial [Internet]. U.S. National Library of Medicine; 2021 [cited 2024 Sept 4]. Available from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7919597/ 
7.  Bishop FL, Aizlewood L, Adams AEM. When and why placebo-prescribing is acceptable and unacceptable: A focus group study of patients’ views [Internet]. U.S. National Library of Medicine; 2014 [cited 2024 Sept 4]. Available from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4089920/ 
8. Marshall M. A placebo can work even when you know it’s a placebo [Internet]. 2016 [cited 2024 Sept 4]. Available from: https://www.health.harvard.edu/blog/placebo-can-work-even-know-placebo-201607079926