Effects of message repetition and negativity on credibility judgments and political attitudes

Research on the truth effect has demonstrated that statements are rated as more credible when they are repeatedly presented. However, current research indicates that there are limits to the truth effect and that too many repetitions can decrease message credibility. This study investigates whether message negativity contributes to this boomerang effect and whether the interaction of credibility and negativity influences political attitudes. These assumptions were tested in an online experiment in which the frequency of exposure to political campaign posters and message negativity were manipulated. The results show that negativity on political campaign posters functions as a crucial moderator, especially in combination with high-frequency exposure. Repeatedly presented negative posters resulted in a more negative attitude toward the presented political issue, which was mediated by a decrease in credibility judgments.