Attitude Certainty and Resistance to Persuasion: Investigating the Impact of Source Trustworthiness in Advertising

Abstract

This experimental study extended previous research concerning cognitive load and source expertise on attitude certainty by replacing source expertise with another component of source credibility, trustworthiness. Under either high or low cognitive load conditions, participants generated counterarguments to a message either high or low in trustworthiness. Participants became more certain of their attitudes when counterarguing a source low in trustworthiness, but only under low cognitive load. The results of this study indicate that source trustworthiness and source expertise may be quite different in their effects on resistance to persuasion and should be considered separately.