Perceived possession of a fictious pain-reduction app induced positive expectancies

Purpose

Prior analgesic placebo research suggested three expectancies underlying placebo analgesia. First, self-related expectancy (expect the self has efficacy to tackle pain). Second, task-related expectancy (expect the cold-pressor-task is easy). Third, object-related expectancy (expect the placebo is highly effective). Recent research reported that possessing a placebo analgesic could sometimes induce placebo analgesia (Yeung et al., 2019; 2020; 2021; 2022), and proposed that such possession-based placebo effect could be due to object-to-self expectancy (expect the owned placebo can benefit the self). We examine whether perceived possession of a pain-reduction object induces these four expectancies.

Method

Participants completed an online survey and were introduced to a mobile app claimed to adopt binaural beats to achieve pain reduction. One group of participants believed that they would receive the app as a gift (perceived possession condition, n=34), while the other group of participants did not (no-possession, n=41). All participants imagined engaging in a cold-pressor-task and rated their expectancies: self-related, task-related, object-related, and object-to-self expectancies.

Results

Participants in the possession (vs. no-possession) condition reported higher self-related expectancy: perceived the self can control the app, p=.03; and have efficacy to tackle pain, p=.04. They also have higher task-related expectancy: perceived the cold-pressor-test to be easier, p=.04. Moreover, they have higher object-related expectancy: expected the app to be effective, p=.02, and fast to reduce pain, p=.05. Lastly, they reported greater object-to-self expectancy: expected the app to benefit the self, p=.02, and reported higher reward response, p=.01.

Conclusion

Perceived possession of a fictitious pain-reduction app induced positive expectancies.