Heuristic processing can bias systematic processing: effects of source credibility, argument ambiguity, and task...

Area of Science:

• Social Psychology
• Cognitive Psychology
• Persuasion Science

Background:

• Attitude formation is influenced by message content and source characteristics.
• Dual-process models propose heuristic and systematic processing routes to persuasion.

Purpose of the Study:

• To investigate how task importance, message ambiguity, and source credibility interact to influence persuasion.
• To examine the interplay between heuristic and systematic processing under varying conditions.

Main Methods:

• Participants (Ss) were assigned to high- or low-task importance conditions.
• They read unambiguous (strong/weak) or ambiguous messages from high- or low-credibility sources.
• Attitudes were measured to assess persuasion effects.

Main Results:

• Low importance: Persuasion solely depended on heuristic processing of credibility.
• High importance, unambiguous messages: Systematic processing dominated when contradicting credibility; both routes influenced attitudes otherwise.
• High importance, ambiguous messages: Both heuristic and systematic processing influenced attitudes, with credibility biasing systematic processing.

Conclusions:

• Task importance critically moderates the influence of heuristic and systematic processing on attitudes.
• Source credibility can bias systematic processing, particularly with ambiguous information.
• Findings have implications for understanding persuasion and social judgment.