Promoting systematic processing in low-motivation settings: effect of incongruent information on processing and judgment.

Ss received consensus information that was either congruent or incongruent with the valence of persuasive message content. In Experiment 1 Ss believed that their processing task was either important or unimportant whereas in Experiment 2 all Ss believed that their task was unimportant. In accord with the heuristic-systematic model's sufficiency principle, high-task-importance Ss exhibited a great deal of systematic processing regardless of congruency, whereas low-importance Ss processed systematically only when they received incongruent messages; in the congruent conditions heuristic processing dominated. Attitude data generally reflected these processing differences and confirmed the additivity and attenuation assumptions of the model. The utility of the sufficiency principle for understanding motivation for elaborative processing and the relevance of the findings to understanding the processing and judgmental effects of expectancy disconfirmation are discussed.