Browsing by Subject "persoonallisuuspiirteet"

This literature review examines how different personality traits are associated with the placebo-effect. Studies from the past decade are reviewed, and the state of the evidence and the possible mechanisms that might explain the connections are discussed. In these recent studies, personality traits have explained about 25 % of the strength of the placebo effect. The specific traits that are found to affect the placebo effect are optimism and pessimism as well as traits that are associated with the dopamine system, namely novelty seeking and extraversion. In addition, some studies have found agreeableness, and ego-resiliency to affect placebo effect. However, the results are not entirely consistent between different studies. Based on the reviewed studies it seems likely that personality traits and their connections to the placebo effect depend on situational and environmental factors: it is the interaction between personality traits and environment that modifies the placebo effect. Thus, the effect of personality traits on the placebo effect is not constant over time but dependent on the environmental factors. In addition, studies also suggest that personality traits and their effect on the placebo effect are mediated via the opioid and the dopamine systems. Finally, replications and new studies are needed to shed more light on the placebo effect.