Comprehension's Role in Persuasion: The Case of Its Moderating Effect on the Persuasive Impact of Source Cues

TLDR

The study manipulated product description comprehension by varying exposure time and prior knowledge across two experiments. The results show that product comprehensibility moderated the influence of source expertise: low comprehension led participants to rely on the inventor’s expertise, whereas high comprehension eliminated this effect, and a pilot study revealed that participants associated comprehensibility with the source and dismissed incomprehensible messages.

Abstract

A study of reactions to a novel product attributed the invention to either an expert or a novice. Comprehension of the product description was manipulated by varying information exposure time (Study 1) and contextual prior knowledge (Study 2). As predicted by the heuristic-systematic model, comprehensibility moderated the persuasive impact of source expertise. When comprehension was low, subjects relied on the inventor's expertise in forming their attitudes toward the product, but when comprehension and, hence, systematic processing were higher, source expertise had no impact on subjects' attitudes. In a pilot study, however, subjects attributed comprehensibility to the source and derogated incomprehensible communications.