A transferable anxiolytic placebo effect from noise to negative effect

Background: The placebo effect in relieving negative emotion arousal is poorly understood.Aims: We examined whether placebo expectation established with noise stimuli could have a transferable anxiolytic effect on negative emotion arousal.Methods: In Experiment 1, noise intensity was surreptitiously lowered during placebo condition in the preconditioning phase to reinforce placebo expectation, and the noise-relieving placebo effect was assessed in the testing phase. In Experiment 2, the same manipulation as in Experiment 1 was administered in the preconditioning phase, but the anxiolytic placebo effect was assessed in the testing phase using negative pictures.Results: Intensity and annoyance by the noise in Experiment 1 were significantly reduced, and unpleasantness in Experiment 2 was also significantly reduced in the placebo condition.Conclusion: Direct noise-relieving placebo effects and transferred anxiolytic placebo effects were found. The present study provides evidence that the placebo effect can be transferred from noise to emotion.