The theory is based on the idea that two cognitions can be relevant or irrelevant to each other (Festinger, 195). These cognitions can be about behaviors, perceptions, attitudes, emotions and beliefs. Often, one of the cognitions in question has to do with our behavior. If cognitions are relevant, they can agree (consistent) or disagree (inconsistent) with each other (Festinger, 195).
The discrepancy between attitude and behavior (eating a donut while thinking about reducing calorie intake) causes a psychological discomfort called cognitive dissonance (Harmon-Jones, 201. Cognitive dissonance leads to motivation to reduce dissonance (Festinger, 195)., the greater the motivation to reduce it (Festinger, 195). Dissonance can also be experienced indirectly through people from a social group with which we identify. When they act incoherently with their attitude, we feel the same discomfort as if we ourselves had acted incoherently with our attitude (Cooper, 201). Cognitive dissonance occurs frequently and affects all of us (Harmon-Jones, 2011. Often, we face cognitive inconsistencies without realizing them).
The first step is to observe the inconsistencies between our thoughts. We can increase our awareness by practicing mindfulness. This includes refraining from judging and instead accepting our observations. Festinger and Carlsmith (195) conducted one of the first studies that examined cognitive dissonance.
Cognitive dissonance is the psychological tension we feel when trying to have two (or more) opposing pieces of information. Usually, we try to eliminate this dissonance by performing a new consonant action or discarding incongruous information. The easiest way for a person to reduce their cognitive dissonance is to convince themselves that there is no conflict. Sweeney, Hausknecht and Soutar (2000) developed a 22-item scale to measure cognitive dissonance immediately after a purchase.
Since it's unlikely that any of us can completely avoid cognitive dissonance, it's important to detect and resolve or reduce it. That's because if you're not aware of yourself, cognitive dissonance can cause you to act and feel quite out of place. It provides an introduction to theory and covers the topics of cognitive dissonance after decisions, the effects of forced compliance, the impacts of voluntary and involuntary exposure to information, and the role of social support. Noulas says that successes in women's rights, environmental rights and the reduction of child marriages are examples of positive changes that have been the result of cognitive dissonance.
This type of incongruity called cognitive dissonance can cause serious mental distress. The brain will try to resolve cognitive dissonance on its own, but that doesn't mean you can't have a say in the process. Psychologist Joel Cooper recently published a comprehensive update to cognitive dissonance theory after more than 50 years of research. The theory of cognitive dissonance itself suggests that if patients invest time, money, and emotional effort in therapy, they are likely to work hard to achieve their therapeutic goals in order to justify their efforts.