Cognitive dissonance theory (CDT) was first introduced by Leon Festinger. Cognitive dissonance is the process by which people detect an inconsistency between cognitions, such as attitudes, beliefs, and behavior. When individuals become aware of an inconsistency between cognitions, they experience a state of psychological discomfort that motivates them to restore consistency. Factors such as the importance of the cognitions and the magnitude of the discomfort play a role in determining how people restore consistency. Festinger described three primary ways people can reduce dissonance: change a cognition; add new cognitions; or change the importance of the inconsistent cognitions. Many early studies showed that when people are unable to change their behavior, they will change their attitudes to be more in line with the inconsistent behavior.
Over the years, CDT has undergone many challenges and revisions. Some revisions focus on the importance of cognitions about the self in the processes by which dissonance motivates attitude change. Others focused on the consequences of the behavior and various cognitive mechanisms that underlie the experience of dissonance. In the early 21st century, research has examined the underlying motivation for dissonance-induced attitude and behavior change, and how people prefer to reduce dissonance once it is present. And, as with the entire field of social psychology, dissonance researchers are also raising concerns about the replicability of classic dissonance effects and focusing their attention on the need to improve the methods the field uses to test predictions going forward.
