Premed · Premed · Introductory Psychology
Lecture 21: Social Psychology I: Attitudes and Persuasion
Introductory Psychology
Learning Objectives
By the end of this lecture, students will be able to:
- Define social psychology and explain the fundamental attribution error
- Distinguish between internal and external attributions and describe attribution biases
- Define attitudes and explain the conditions under which attitudes predict behavior
- Describe cognitive dissonance theory and self-perception theory
- Explain the routes to persuasion and the factors that influence attitude change
Lecture Content
I. Introduction to Social Psychology
Social psychology is the scientific study of how people think about, influence, and relate to one another. A core theme running through the field is the remarkable power of the social situation to shape behavior. People consistently underestimate the influence of situational factors while overestimating the role of personal dispositions. The field is organized around three broad domains: social thinking (attitudes and attributions), social influence (conformity and obedience), and social relations (aggression, attraction, and helping behavior).
II. Attribution: Explaining Others' Behavior
Attribution is the process of explaining the causes of behavior. Fritz Heider (1958) proposed that people function as "naive scientists," constantly trying to understand why others behave as they do. An internal (dispositional) attribution explains behavior in terms of the person's traits, abilities, or character — "She failed because she's lazy." An external (situational) attribution points to environmental factors or circumstances — "She failed because the test was unfair."
Harold Kelley's covariation model describes how we weigh three types of information when making attributions. Consistency asks whether the person behaves this way regularly in this situation. Distinctiveness asks whether the behavior occurs only in this particular situation. Consensus asks whether other people behave similarly in the same situation. When consistency, distinctiveness, and consensus are all high, we tend to make an external attribution. When consistency is high but distinctiveness and consensus are low, we tend to make an internal attribution.
The fundamental attribution error (FAE), also called the correspondence bias, is the pervasive tendency to overattribute others' behavior to internal dispositions while underestimating situational factors. Jones and Harris (1967) demonstrated this powerfully: participants judged essay writers as genuinely holding the position they argued, even when they were told the topic had been assigned. This bias is more pronounced in individualistic (Western) cultures than in collectivistic (East Asian) ones. The actor-observer bias is a related asymmetry: we tend to attribute our own behavior to situational factors but explain others' behavior in dispositional terms. The self-serving bias protects self-esteem by attributing our successes to internal factors and our failures to external ones.
III. Attitudes
An attitude is a learned, relatively stable evaluation — positive or negative — of a person, object, or idea. The ABC model describes three components of attitudes: the affective component (emotional feelings), the behavioral component (actions or behavioral tendencies), and the cognitive component (beliefs and thoughts).
Early research, notably by LaPiere in 1934, suggested that attitudes often fail to predict behavior. The modern consensus, however, is that attitudes do predict behavior under specific conditions: when the attitude is strong, specific, and easily recalled; when it is relevant to the behavior in question; when situational pressures are minimal; and when the person is aware of their attitude. Ajzen's theory of planned behavior formalizes this understanding, proposing that behavior is best predicted by behavioral intentions, which are in turn shaped by the attitude toward the behavior, subjective norms, and perceived behavioral control.
Implicit attitudes are unconscious, automatic evaluations that can be measured by the Implicit Association Test (IAT), which assesses the speed of associations between concepts and evaluations. Implicit attitudes can diverge from explicit (conscious) attitudes: implicit attitudes tend to predict spontaneous behavior, while explicit attitudes predict more deliberate actions.
IV. Cognitive Dissonance
Leon Festinger's cognitive dissonance theory (1957) proposes that holding two inconsistent cognitions, or behaving in a way that contradicts one's attitudes, creates an unpleasant state of psychological tension called dissonance. People are motivated to reduce this dissonance by changing their attitudes, changing their behavior, or adding new cognitions that rationalize the inconsistency.
The classic demonstration was the Festinger and Carlsmith experiment of 1959. Participants performed a boring task and were then paid either $1 or $20 to tell the next participant that the task was interesting. The counter-intuitive finding was that participants in the $1 group — who had insufficient external justification for lying — experienced more dissonance and consequently changed their attitude, coming to believe the task was actually somewhat enjoyable. The $20 group had sufficient external justification and felt no need to change their views. In short, less reward produced more attitude change.
Dissonance is most likely when behavior is perceived as voluntary, when there is insufficient external justification, when the person is aware of the conflict, and when the consequences are foreseeable and irrevocable. Dissonance theory explains several phenomena: effort justification (we value outcomes more when we have worked hard for them), post-decision dissonance (we elevate chosen options and devalue rejected ones after making a difficult choice), and induced compliance (agreeing to a counter-attitudinal action shifts our attitudes to match).
Daryl Bem's self-perception theory (1972) offers an alternative explanation: when attitudes are weak or ambiguous, we simply infer them by observing our own behavior — "I must enjoy running, because I run every day." Self-perception theory best explains the formation of new attitudes, while dissonance theory better accounts for changes in existing attitudes.
<image>A diagram of Festinger's cognitive dissonance theory. Panel A: The classic $1/$20 experiment shown in three steps — participants do a boring task, then tell the next person it was fun for either $1 or $20, then rate how much they actually enjoyed the task. A bar graph shows that the $1 group rated the task as more enjoyable than the $20 group or the control group. Panel B: A conceptual diagram showing two contradictory cognitions ("I am honest" and "I just lied") creating tension (dissonance), with three resolution arrows: change the attitude, change the behavior, or add a new cognition to rationalize. Panel C: Effort justification — two paths, one requiring high effort and one requiring low effort, leading to the same outcome, with the high-effort path producing greater valuation of the outcome.</image>
V. Persuasion
The Elaboration Likelihood Model (ELM), developed by Petty and Cacioppo, identifies two routes through which attitudes can be changed. The central route involves careful, thoughtful consideration of the message content and the quality of its arguments. It requires both motivation and ability to process the message and produces durable, resistant attitude change. The peripheral route involves superficial processing based on cues unrelated to argument quality — the speaker's attractiveness, the number of arguments (regardless of quality), emotional appeals, or celebrity endorsements. It is used when motivation or ability to process is low and produces temporary, less stable attitude change.
Several factors influence the effectiveness of persuasion. Regarding the source, credibility (expertise combined with trustworthiness), attractiveness, and similarity to the audience all matter. Regarding the message, two-sided arguments are more effective with informed audiences, and fear appeals work best when paired with specific coping strategies (fear alone can backfire). The primacy effect gives an advantage to arguments presented first (for attentive audiences), while the recency effect favors arguments presented last (when a delay separates message from decision). Regarding the audience, young adults are most susceptible to attitude change, people high in need for cognition respond more to central-route arguments, and forewarning about a persuasion attempt increases resistance. Face-to-face communication tends to be the most persuasive channel, while written messages allow more deliberation.
Resistance to persuasion can be built through inoculation — exposure to weakened counter-arguments, which functions like a psychological vaccine. Strong attitudes rooted in personal experience are harder to change. Reactance occurs when people feel their freedom is threatened, prompting them to adopt the opposite position.
<image>A visual representation of the Elaboration Likelihood Model of persuasion. Panel A: A flowchart starting with "Persuasive message received" leading to a decision point: "High motivation and ability to process?" If yes, arrow leads to "Central route" (deep processing of argument quality) → "Durable attitude change." If no, arrow leads to "Peripheral route" (reliance on surface cues: attractiveness, emotion, number of arguments) → "Temporary attitude change." Panel B: A table of persuasion factors organized by Source (credibility, attractiveness), Message (quality, fear appeals, framing), Audience (age, need for cognition, forewarning), and Channel (face-to-face, media, written), with brief descriptions of how each factor affects persuasion effectiveness.</image>
VI. Conformity and Social Influence (Introduction)
Automatic mimicry, or the chameleon effect, is the unconscious tendency to imitate others' postures, gestures, and facial expressions, which facilitates social bonding and rapport. Conformity is the broader process of adjusting one's behavior or thinking to align with group norms. Informational social influence drives conformity in ambiguous situations when others seem to possess useful information, often producing genuine private acceptance — a real change in belief. Normative social influence drives conformity when the goal is to gain social approval or avoid rejection, typically producing public compliance without private belief change.
Solomon Asch's 1951 line judgment study provided a dramatic demonstration of normative social influence. Participants conformed to a clearly incorrect majority answer approximately 37% of the time. Conformity increased with group size (up to about three or four members) and with the unanimity of the group, but it dropped dramatically when even a single other person dissented. The study vividly illustrates the power of social pressure to override one's own perceptions, even when the correct answer is unambiguous.
