APA Dictionary of Psychology

Motivation and Opportunity as Determinants theory: a theory of attitude–behavior consistency postulating that the process by which attitudes influence behavior differs according to the amount of deliberation involved. When people are motivated and able to deliberate about their actions, attitudes influence behavior in a manner similar to that postulated by the theory of reasoned action. When people are not motivated or able to deliberate about their actions, attitudes toward the target of the behavior can be activated in memory and affect the way the target is perceived. These perceptions in turn influence how people define the behavioral event (e.g., as a situation in which the target should be approached or avoided). The definition of the behavioral event in turn determines behavior. [originally developed by U.S. psychologist Russell H. Fazio (1952–  )]