Neural Predictors of Message Effectiveness during Counterarguing in Antidrug Campaigns

A substantial amount of research has focused on predicting the effectiveness of persuasive messages. However, characteristics of both the message itself and its receiver can impact theoretically predicted effects. For example, recent work published in this journal demonstrated that issue involvement modulates the relationship between message sensation value (MSV) and argument strength (AS). When exposed to anti-cannabis public service announcements (PSAs), high-drug-risk individuals rate these messages as having low effectiveness regardless of variation in MSV and AS. Accordingly, for high-risk individuals, MSV and AS lose their predictive power in message design; moreover, the all too common use of high MSV, high AS PSAs to dissuade drug use may be ineffective, as high-risk viewers are more likely to engage in counterarguing. In this paper, we use functional magnetic resonance imaging to investigate the neural correlates of counterarguing. Subsequently, we employ a brain-as-predictor approach using neural activation and self-report data to predict message effectiveness in two independent samples. We demonstrate that by adding two neural predictors within the middle frontal gyrus and superior temporal gyrus to self-report data, the prediction accuracy of message effectiveness in high-drug-risk individuals during counterarguing can reach, and even surpass, the prediction accuracy for low-drug-risk individuals.