Placebo and Nocebo Effects in Chronic Pain Patients
How Expectations and Emotional Feelings Contribute to the Experience of Pain
Abstract
Placebo, as well as nocebo, effects have been primarily investigated in studies with healthy volunteers exposed to acute experimental pain. Yet with regard to chronic pain patients, there is emerging evidence for significant placebo effects but not for nocebo effects. Expectations of pain relief are known to contribute to placebo effects, and lately the influence of emotional feelings has also been investigated. In this line of research, an experiential method has been applied to capture the emotional feelings that chronic pain patients experience during placebo and nocebo interventions. The findings indicate that the patients’ expectations of treatment effects are highly embedded in their emotional feelings. Hence, in order to optimize placebo factors in the clinical treatment of patients, it may be pivotal to investigate and enhance both expectancies and emotional feelings about treatments.
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