Social psychology asks: how does the presence of other people change what we do? Humans are exquisitely sensitive to their social environment — sometimes performing better, sometimes worse, sometimes abandoning their own moral judgment entirely. These mechanisms connect directly to health behavior and clinical compliance — why patients do (or do not) follow medical advice.
Priority labels: Must know = cold; Know the logic = mechanism not names; Passage-level = recognize, don't memorize; Optional = skippable.
Social Facilitation
The Core Idea
Must knowSocial facilitation is the tendency for the presence of others to influence performance. Practicing a well-mastered skill, you perform better when watched; still learning a hard skill, that same audience makes you stumble.
Passage-levelNorman Triplett (1898) first noticed cyclists rode faster competing alongside others. Robert Zajonc (1965) provided the explanation the MCAT tests.
Zajonc's Drive Theory
Must knowThe mere presence of others causes physiological arousal, which increases the dominant response — the most well-learned or habitual behavior for that person in that situation.
- Well-learned (easy) task: dominant response is correct → arousal → enhanced performance
- Novel (hard) task: dominant response may be incorrect → arousal → impaired performance
Key chain: Others present → arousal → strengthened dominant response → performance improved (easy) or impaired (hard).
Quick check: A medical student performs a physical exam maneuver she has done thousands of times. An attending enters. Per Zajonc, how does her performance change, and why?
Answer: It likely improves. The maneuver is well-learned, so her dominant response is the correct one; the arousal from the attending's presence strengthens it.
Deindividuation
Losing Yourself in the Crowd
Must knowDeindividuation is the loss of individual identity and personal responsibility in a group, weakening normal inhibitions and increasing impulsive, antisocial, or norm-violating behavior. Philip Zimbardo developed the concept. The key point: the psychological restraints that usually govern behavior (self-awareness, accountability) are reduced.
Know the logicFactors that promote it: anonymity (uniforms, masks, large crowds), large group size, high arousal, and reduced self-awareness.
Passage-levelExplains mob violence, looting, online harassment (internet anonymity), and the cruelty of guards in Zimbardo's Stanford Prison Experiment.
Quick check: During a large protest, a normally peaceful person throws objects at police — something he would never do alone. Which concept explains this?
Answer: Deindividuation. The crowd provides anonymity and reduced accountability, weakening his normal inhibitions.
Bystander Effect
The Paradox of Safety in Numbers
Must knowBystander effect: the probability that any one individual helps a person in need decreases as the number of bystanders increases. The classic catalyst was the 1964 Kitty Genovese murder, which led John Darley and Bibb Latané to study it systematically.
Mechanisms: Why Bystanders Don't Help
Must knowTwo processes:
1. Diffusion of responsibility: with many people present, personal obligation to act is spread across the group — "someone else will handle it."
2. Pluralistic ignorance: in ambiguous situations people read others' (masked) calm as evidence there's no emergency, so the group collectively misreads the situation.
OptionalThe five-step decision model. A bystander must (1) notice the event, (2) interpret it as an emergency, (3) assume responsibility, (4) know how to help, (5) decide to act. More bystanders create friction mainly at steps 2 and 3.
Quick check: A participant alone sees smoke seep under a door; in another condition, two calm stooge bystanders are present. What happens, and why?
Answer: Alone, the participant reports the smoke quickly. With calm stooges present, they're far less likely to report — pluralistic ignorance (calm others read as "no emergency") and diffusion of responsibility reduce the urge to act.
Social Loafing
When Groups Make Us Lazy
Must knowSocial loafing is the tendency to exert less effort on a collective task in a group than when working alone. (Contrast social facilitation, which is about a watching audience.) Max Ringelmann (1913) first showed this in rope-pulling — per-person effort fell as team size grew (the Ringelmann effect).
Know the logicWhy it happens: reduced identifiability (your low effort can't be singled out), diffusion of responsibility, and equity concerns ("why be the sucker?").
Know the logicWhat reduces it: make individual contributions identifiable, increase task meaningfulness, use smaller groups, raise group cohesion.
Passage-levelLoafing is stronger in individualistic cultures; collectivistic cultures sometimes show increased group effort.
Quick check: A professor assigns a group project to 20 students and suspects social loafing. What single evidence-based change reduces it most?
Answer: Make individual contributions identifiable (e.g., a personal reflection or individual presentation). When individuals can't hide in the collective, loafing drops substantially.
Social Control
The External Pressure to Conform to Norms
Must knowSocial control = the formal and informal mechanisms by which society regulates behavior to enforce norms and maintain order. Primarily a sociological (SOC) concept.
The formal vs. informal distinction:
- Formal: official agents and codified rules — laws, courts, police, prisons, licensing/medical boards.
- Informal: everyday social pressure — ridicule, ostracism, gossip, disapproval, shaming.
Sanctions enforce conformity: positive (praise, awards, acceptance) or negative (fines, imprisonment, exclusion). Deviance — behavior violating norms — triggers social control, and is socially defined rather than inherent (a key sociological insight).
Quick check: A physician is reprimanded by the state medical board for guideline-violating prescribing; a rude dinner guest gets the cold shoulder. Which is formal, which informal?
Answer: The board reprimand is formal (official institution, codified standards); the dinner-party ostracism is informal (social disapproval, no official mechanism).
Peer Pressure
The Pull of the Peer Group
Must knowPeer pressure is direct or indirect influence from one's peer group to conform to its norms, attitudes, or behaviors — especially salient in adolescence. It can be explicit ("just try it") or implicit (feeling pressure simply from seeing peers do something).
Know the logicWhy it works: it taps the need to belong (exclusion is painful, so we conform to avoid rejection) and the need for information (we use peers as a reference for what's "normal"). These map onto normative vs. informational social influence (see Conformity).
Passage-levelHighly relevant to health — substance use, risky sexual behavior, diet, exercise, and help-seeking are shaped by peer norms.
Quick check: A student doesn't want to drink, but all her friends are drinking and she feels out of place. No one pressured her. What type of peer pressure, and what motivation?
Answer: Implicit peer pressure, driven by the need to belong — she conforms to avoid social exclusion, not because anyone asked.
Conformity
Why We Go Along with the Group
Must knowConformity is a change in beliefs, attitudes, or behaviors in response to real or imagined group pressure. The foundational work is Solomon Asch's 1950s line-judgment studies.
The Asch Conformity Experiments
Must knowParticipants judged which comparison line matched a target — an obvious answer. Seated among confederates who unanimously gave a wrong answer, a substantial fraction of participants conformed to the obviously incorrect answer on at least one trial (people alone chose correctly almost every time). The lesson: even in unambiguous situations, social pressure produces conformity.
Know the logicModerating factors: one dissenter dramatically reduces conformity (unanimity matters); conformity rises with group size up to ~3–4; greater task ambiguity increases conformity.
Two Mechanisms of Social Influence (Deutsch & Gerard)
Must know1. Normative social influence: conforming to gain acceptance / avoid rejection without believing the group is right → compliance (public agreement, private disagreement).
2. Informational social influence: conforming because you believe the group has better information, especially when ambiguous → internalization (genuine private belief change).
A third type, identification, is conforming because you want to be like an admired group.
Types of Conformity (Kelman)
Know the logic| Type | Public Behavior | Private Belief | Driver |
|---|---|---|---|
| Compliance | Changes | No change | Normative; avoid punishment / gain reward |
| Identification | Changes | May partially change | Wanting to be like an admired group |
| Internalization | Changes | Changes | Genuine belief group is correct; informational |
What increases conformity: group unanimity, larger size (up to ~4), ambiguity, high cohesion and perceived expertise, public (vs. private) responses; collectivistic cultures tend to conform more.
Quick check: In an Asch-style study, the group's wrong answer is made only slightly off rather than obviously wrong. How do conformity rates change, and which influence dominates?
Answer: Conformity increases. Greater ambiguity means less confidence in one's own judgment, raising informational social influence — the group becomes a legitimate information source, not just social pressure.
Obedience
Following Orders: The Milgram Experiments
Must knowObedience is complying with a direct order from an authority figure — a hierarchical relationship, unlike conformity (peer pressure). The defining research is Stanley Milgram's 1960s experiments.
Milgram's Procedure
Must know"Teacher" participants were ordered by a lab-coated experimenter to deliver escalating "shocks" to a "learner" (a confederate) for wrong answers, up through labels like "Danger: Severe Shock." Key finding: roughly two-thirds continued to the maximum despite the learner's apparent screams and silence — far higher than experts predicted. Ordinary people obey legitimate authority to a disturbing degree.
Factors That Modulate Obedience
Know the logicObedience is higher when the authority is physically present and legitimate (e.g., Yale vs. a run-down office) and when the victim is distant/unseen. It is lower when the victim is close (seen/heard or touched), the authority is remote (orders by phone), or peers rebel (confederate co-teachers refusing collapses obedience).
The Stanford Prison Experiment (Zimbardo, 1971)
Passage-levelStudents randomly assigned as "guards" or "prisoners" in a mock prison; stopped early as guards turned cruel and prisoners broke down. Cited as evidence that situational forces and role assignment can override individual character. (Methodology is heavily criticized; the MCAT tests it as a named illustrative study, not a rigorous experiment.)
Obedience vs. Conformity — A Critical Distinction
Must know| Feature | Conformity | Obedience |
|---|---|---|
| Source | Peers / group | Authority figure |
| Explicit command? | No — implicit pressure | Yes — direct order |
| Hierarchy? | No (horizontal) | Yes (vertical) |
| Classic study | Asch | Milgram |
Quick check: Participants who shock someone in the next room obey more than those face-to-face with the victim. What mechanism explains this, and what variable was manipulated?
Answer: Milgram manipulated proximity to the victim. Physical/psychological distance reduces empathy and makes the victim's suffering abstract, so continuing is easier.
Compliance Techniques
Getting to "Yes" Without Authority or Conformity
Must knowCompliance here means changing behavior in response to a direct request from someone with no authority over you — distinct from conformity (no group pressure) and obedience (no command). Recognize these by name:
- Foot-in-the-door: small request first, then a larger one; having already agreed (and now seeing themselves as cooperative/consistent), the target is more likely to agree to the bigger ask.
- Door-in-the-face: large, refused request first, then retreat to the smaller request you actually wanted, which now seems reasonable by contrast (reciprocal concession).
- Lowball: secure agreement, then reveal worse terms; prior commitment keeps the person in.
Quick check: A salesperson agrees on a price, then "checks with the manager" and returns saying it must be higher due to an overlooked fee. The committed customer accepts. Which technique?
Answer: Lowball. Initial commitment makes the customer reluctant to back out even after terms worsen.
Common Confusions & Tricks
1. Social facilitation vs. social loafing — easy to mix up.
- Facilitation: others are watching; the task matters (easy = better, hard = worse).
- Loafing: others are working with you on a collective task; effort drops because it's pooled. Mnemonic: loafing = lazy in a group; facilitation = fancy performance under observation.
2. Diffusion of responsibility ≠ pluralistic ignorance.
- Diffusion of responsibility: who feels obligated ("someone else will do it").
- Pluralistic ignorance: how the situation is interpreted ("no one looks worried, so it's not an emergency").
- Both feed the bystander effect but are distinct mechanisms.
3. Normative vs. informational influence — know which produces which.
- Normative → compliance (public change only; you privately disagree). Asch's participants mostly showed this — they knew the answer was wrong.
- Informational → internalization (genuine belief change); more prominent when ambiguous.
4. Conformity vs. obedience — not interchangeable.
- Conformity is horizontal (peer group, no explicit command); obedience is vertical (authority, direct command).
- "The researcher told the participant to continue" → obedience. "The others all agreed with the wrong answer" → conformity.
5. Zajonc's dominant response goes both ways.
Others improve easy tasks and impair hard tasks. A novice performing worse with an audience is social facilitation working as predicted — don't second-guess it.
6. Zimbardo wears two hats.
He's tied to both deindividuation and the Stanford Prison Experiment (situational influences on cruelty). Both are fair game.
7. Milgram's headline result.
Recall that a shockingly high proportion (roughly two-thirds) delivered the maximum shock — the point is that experts underestimated obedience. Recall the magnitude, not a precise percentage, and don't confuse it with Asch's conformity finding.
8. Social control = formal AND informal.
Don't think only of laws and police; informal control (gossip, shame, exclusion) is equally important and often more immediate.
9. "Compliance" has two meanings — keep them separate.
As a conformity outcome (Kelman): public agreement without private belief change. As a social-influence category: saying yes to a direct request, using the named compliance techniques. A persuasion/sales tactic with no group consensus and no authority command is a compliance technique — not conformity or obedience.
10. Diffusion of responsibility is the connecting thread.
Feeling less personally responsible because responsibility is spread across a group underlies social loafing (effort drops), deindividuation (inhibitions drop), and the bystander effect (helping drops). "Someone else will handle it" → diffusion of responsibility.
Key Theories & Terms
| Term / Name | What It Means / Who |
|---|---|
| Social facilitation | The presence of others enhances performance on easy/well-learned tasks and impairs performance on difficult/novel tasks |
| Norman Triplett | First empirical observation of social facilitation (1898 cyclist studies) |
| Robert Zajonc | Developed the drive theory of social facilitation; proposed that others' presence causes arousal, which strengthens the dominant response |
| Dominant response | Zajonc's term for the most well-learned or habitual behavior in a given situation |
| Deindividuation | Loss of individual identity and reduced self-awareness in groups, leading to weakened behavioral inhibitions |
| Bystander effect | The more bystanders present in an emergency, the less likely any one of them is to help |
| Kitty Genovese | 1964 murder case that inspired Darley and Latané's systematic study of bystander behavior |
| John Darley & Bibb Latané | Researchers who identified and experimentally studied the bystander effect |
| Diffusion of responsibility | Each bystander feels less personally obligated to act because responsibility is shared across the group |
| Pluralistic ignorance | Bystanders each use others' apparent calm as evidence the situation is not an emergency, leading to collective inaction despite individual concern |
| Social loafing | Individuals exert less effort on a collective task when working in a group than when working alone |
| Ringelmann effect | Max Ringelmann's (1913) original observation that per-person effort in rope-pulling decreases as group size increases |
| Social control | Mechanisms (formal and informal) by which society enforces norms and regulates behavior |
| Formal social control | Regulation through official institutions: laws, courts, medical boards, police |
| Informal social control | Regulation through everyday social processes: gossip, shaming, ostracism, disapproval |
| Sanctions | Rewards or punishments used to enforce conformity to social norms |
| Peer pressure | Direct or indirect influence from one's peer group to conform to group norms or behaviors |
| Conformity | Changing beliefs or behaviors in response to real or imagined social group pressure |
| Solomon Asch | Conducted the landmark line-judging conformity experiments demonstrating that many people conform to an obviously wrong group consensus at least once |
| Normative social influence | Conforming to gain acceptance or avoid rejection; produces compliance (public change, no private belief change) |
| Informational social influence | Conforming because you genuinely believe the group has better information; produces internalization |
| Compliance | Public conformity without private belief change; driven by normative influence |
| Identification | Conformity driven by wanting to be like an admired group; behavior changes while the association lasts |
| Internalization | Deepest form of conformity; genuine private belief change; driven by informational influence |
| Herbert Kelman | Classified conformity into three types: compliance, identification, and internalization |
| Deutsch & Gerard | Distinguished normative from informational social influence (1955) |
| Obedience | Complying with a direct order from an authority figure |
| Compliance techniques | Strategies that increase agreement to a request from someone with no authority: foot-in-the-door, door-in-the-face, lowball |
| Foot-in-the-door | Small request first, then a larger one; prior agreement makes the bigger ask more likely to succeed |
| Door-in-the-face | Large request first (refused), then a smaller one that seems reasonable by contrast |
| Lowball | Get commitment to a deal, then worsen the terms; prior commitment keeps the person in |
| Stanley Milgram | Conducted the landmark obedience experiments; found that a large majority of participants delivered maximum apparent shocks under authority pressure |
| Philip Zimbardo | Associated with both deindividuation theory and the Stanford Prison Experiment; showed how roles and situations shape behavior |
| Stanford Prison Experiment | Zimbardo's 1971 study in which random role assignment as "guard" or "prisoner" rapidly produced abusive behavior; stopped early; landmark in situational determinism and research ethics |