Jack Brehm was an American social psychologist who is best known for his research on cognitive dissonance and reactance theory. His work on cognitive dissonance showed that when people experience a conflict between their attitudes or beliefs and their behaviors, they experience psychological discomfort, which can lead to changes in attitudes or behaviors to reduce the dissonance. Brehm also developed the reactance theory, which explains how people react when their freedom to engage in a behavior is threatened or restricted. According to reactance theory, people may become more motivated to engage in a behavior when they feel that their freedom to do so is being threatened. Brehm's work has had a significant impact on the fields of social psychology and communication.

Robert Cialdini is a social psychologist who has extensively researched the concept of psychological reactance. Psychological reactance occurs when individuals perceive a threat to their freedom or autonomy and respond by trying to assert their independence. Cialdini's research shows that when individuals feel that their freedom is being restricted, they may react with increased resistance and defiance, and may even become more motivated to engage in the restricted behavior. Cialdini's work has shown that reactance can have significant effects on persuasion and communication, and that understanding reactance can help individuals and organizations to communicate more effectively.