The placebo effect is well known by now: If a person is given an inert treatment, say, a pill, and is told it provides pain relief, that person will report a reduction in perceived pain despite there being no active ingredients. While this phenomena was traditionally treated as an irritant variable in clinical trials, there has been a renewed interested in recent years. These researchers, however, view placebos not as a nuisance, but a valuable tool. In fact, the Program in Placebo Studies and Therapeutic Encounters is a research center at Harvard University with the central goal to advance our understanding of placebos and their potential applications.
But there is a lesser known subfield within this vein of research—non-deceptive placebo effects. This phenomena, also known as open-label placebo effects, occurs when patients know they are being administered an inert treatment, yet still experience improved clinical outcomes. While this stream of research is still burgeoning, it has been documented in irritable bowel syndrome, chronic lower back pain, depression, attention-deficient hyper disorder, rhinitis, and cancer-related fatigue. The mechanisms that determine the extent of non-deceptive placebos efficacy aren’t clear, but it’s thought that they retrieve a pharmacological memory, which acts as a trigger to previously conditioned responses. Put simply, while our conscious minds might be aware that we’re taking a sugar pill, our unconscious mind receives environmental signals, such as the pill and clinical environment it is being consumed in, to determine a response.
In a recent study participants in the testing group were administered a nasal spray they were told had no active ingredients but would help reduce their negative feelings only if they thought it would. Interestingly, these participants exhibited less emotional distress when viewing emotionally negative images. The reduced distress was verified using two measures: self-report from participants and electroencephalography that measured the neural markers.*
The ethics surrounding the use of placebo is a prickly issue. The thought of prescribing an inactive treatment unbeknownst to the patient can deeply erode the doctor-patient relationship. However, non-deceptive placebos theoretically remediates the bulk of the concern because doctors can maintain transparency with patients. However, while one survey found support for non-deceptive placebos among patients, the reasons for it and extent of its application varied, indicating this as a likely hurdle that will have to be addressed before it can be brought mainstream.
Although there is much to be known about the conditions and extent to which the self-deceptive placebo effect holds, it serves as a powerful testament to the depth of human perception. While people like to think their conscious, rational mind is the primary driver of their behavior, the non-deceptive placebo effect illustrates human perception is rooted in the unconscious and the complexity of the mind-body relationship.
*You can find the full article here.
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