Abstract

This study examined the effect of positive affect induced by savoring on the formation of nocebo in case of somatization tendency when provided with side effect information. To this end, 390 adults among those with the top 30% of BSI-18 somatization scores were selected. They were considered to have a somatization tendency. Those who met the screening criteria were randomly assigned to either a positive affect group or a neutral affect group to perform affect-induced writing tasks. All participants then conducted a procedure called Sham tDCS. They were informed about side effects such as headaches. Finally, a simple fake cognitive performance task was performed to maintain the cover story. In the final analysis, using data from 52 successfully controlled participants, the positive affect group reported less frequent headaches than the neutral affect group. There was no significant difference in the incidence or the strength of headaches. This study sought an in-depth understanding of the nocebo known to contribute to somatization tendency's medication and treatment non-adherence. It provided basic data for the development of efficient intervention. Based on these findings, implications, limitations, and follow-up studies of this study were discussed.