If people thought completely rationally when told arguments on two sides, they would remember the most plausible. Dissonance theory predicts that instead they will remember the most plausible arguments from the side they agree with and the most implausible from the one they disagree with. This is not rational but confirms their beliefs and prevents dissonance. 

Arguments under dissonance theory

After making decisions, people are more likely to rate their decision as positive even if no change in circumstance has occurred other than the decision. For example, when people are told to value different appliance, they rate the appliance higher after they given that appliance as a gift, even if they have not yet used it. Another way to think of this is that people rationalize past decisions with their judgements. 

Decisions under cogntive dissonance theory

Much of human thought and behavior isn't rational, but rationalizing. When people are cognitively dissonate, they spend a lot of time convincing themselves that they are right. 

University of Michigan - Ann Arbor

A state of mind that occurs when there a person holds two or more inconsistent cognitions (i.e., ideas, attitudes, beliefs, opinions, etc.) It results in an unpleasant feeling of mental discomfort and is not the product of a physiological need. This discomfort is hypothesized to be a result of our desire find reason in the world and erase absurdity. Another way at looking at it is that it occurs when our self-justifications conflict. 

Cognitive Dissonance

Aronson, Elliot, and Joshua Aronson. The Social Animal. Worth Publishers, Macmillan Learning, 2018.

The Social Animal

Rational v. Rationalizing in dissonance theory

Subsequent research on cognitive dissonance has specified that the discomfort is not caused by any conflicting cognitions, but specifically by those that challenge an individual's positive self-image.

Role of Self-Image in Cognitive Dissonance

In addition to being psychologically uncomfortable, cognitive dissonance has measurable physical effects. Research has shown it can cause physiological arousal and activate specific regions of the brain associated with emotions and cognitive functioning.

Physiological and Neurological Effects of Cognitive Dissonance

The experience of cognitive dissonance is psychologically, physically, and mentally uncomfortable, which creates a strong motivation for individuals to reduce this discomfort. The primary method for reduction involves restoring harmony by aligning one's cognitions, attitudes, and behaviors. This can be accomplished through several strategies, such as altering existing cognitions to justify behavior, adding new cognitions that bridge the gap between conflicting ideas, or changing one's behavior to match their beliefs.

Motivation and Methods for Reducing Cognitive Dissonance

To alleviate the tension of cognitive dissonance, individuals can change their conflicting behavior, alter their attitudes or cognitions to create alignment, or introduce a new cognition that justifies the inconsistency.

Methods to Reduce Cognitive Dissonance

An individual strongly believes that protecting the environment is a moral duty and actively participates in local recycling programs. This person then purchases a new, large SUV with very poor fuel efficiency because they need more space for their family. Which of the following psychological experiences is this individual most likely to have as a direct result of this situation?

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