Date of Completion


Embargo Period



information processing theory, message discrepancy, attitude and behavior change, emotional ambivalence, fast food consumption

Major Advisor

Mark Hamilton

Associate Advisor

Leslie Snyder

Associate Advisor

Qing Cao

Field of Study

Communication Sciences


Doctor of Philosophy

Open Access

Campus Access


This dissertation applies the omnistructure model of information processing theory as a framework for understanding how young adults process warning messages about fast food. Message receivers’ cognitive and emotional processing of warning messages is explored in the layers of topic evaluation and message evaluation. This dissertation posits that interplays of emotional factors (e.g. emotional involvement, emotional ambivalence, primary and secondary emotions) and cognitive response factors (e.g. motivation to eat, risk threat assessment and attitude) will have an impact on behavior intention during information processing, and ultimately influence future behavior. Two studies were conducted to examine how warnings influence the interplay of topic and message evaluations. In the pilot study (N = 599), warnings about three fast food products changed viewer attitudes to be significantly less favorable. Message strength, along with source evaluation and counterarguing, amplified the effect of message discrepancy on attitude change. Causal modeling indicated a dynamic interplay between the emotional and cognitive evaluation of fast food eating. In the main study (N = 706), a 2 (message frame: gain vs. loss) x 2 (issue reference target: firm vs. food) x 2 (conclusion specificity: explicit vs. implicit) factorial design found that warnings advanced a comprehensive interplay of cognitive and affective factors during information processing. This interplay not only had an effect on post-message behavior intention but also on future fast food eating behavior that was measured one month later. Beyond the findings of the two experiments, this dissertation adds knowledge of the factors that influence the processing and persuasive effects of the fast food warnings.