Group Psychology
High-Yield Summary
- Social action (Weber) = behavior performed because others are present. Social facilitation = performance improves on simple/familiar tasks (not complex ones) when watched, via Yerkes-Dodson law: presence of others raises arousal.
- Deindividuation = anonymity in large/uniform/masked groups → loss of individual identity → antinormative behavior (proposed explanation for riot/crowd violence).
- Bystander effect: likelihood/speed of helping is inversely related to number of bystanders — driven by reduced danger-noticing, social etiquette, cue-taking, felt responsibility, and group cohesiveness (strangers = slower response).
- Social loafing = reduced individual effort (physical/mental/initiative) in group settings — contrast with social facilitation (performance ↑ from being watched) vs. loafing (effort ↓ from diffused responsibility).
- Peer pressure works via the identity shift effect (conform to resolve threat of social rejection) and cognitive dissonance (discomfort from 2 opposing thoughts). Asch's conformity experiments: people gave answers they knew were false to avoid opposing the group.
- Group polarization (individual-level) = choice shift (group-level, originally 'risky shift') — groups reach more extreme decisions (riskier OR more cautious) than members' initial inclinations. Same phenomenon, different levels of analysis.
- Groupthink = harmony-driven suppression of critical evaluation. Janis's 8 symptoms: illusion of invulnerability, collective rationalization, illusion of morality, excessive stereotyping, pressure for conformity, self-censorship, illusion of unanimity, mindguards.
- Assimilation = cultures merging into one ('melting pot'); multiculturalism = distinct cultures coexisting/celebrated ('cultural mosaic') — near-opposite processes. Ethnic enclaves slow assimilation. Subculture = distinguishes from primary culture; counterculture = subculture that deliberately opposes majority culture.
Key Terms
- Social facilitation
- Performance improves on simple/well-practiced tasks (worsens on complex ones) when others are watching, via raised arousal.
- Deindividuation
- Loss of individual identity in a large/anonymous group, enabling antinormative behavior.
- Social loafing
- Reduced individual effort when working in a group setting.
- Identity shift effect
- Mechanism of peer pressure: adopting group standards as one's own to resolve internal conflict from threatened rejection.
- Group polarization / choice shift
- Groups reach more extreme decisions than members' individual starting positions; 'risky shift' was the original name before caution-shift was found.
- Groupthink
- Desire for harmony/conformity causes a group to reach an incorrect or poor decision, suppressing alternative viewpoints.
Social Facilitation vs. Social Loafing vs. Bystander Effect
| Phenomenon | Mechanism |
|---|---|
| Social facilitation | Arousal from being evaluated → better performance on simple tasks |
| Social loafing | Diffused effort/responsibility across the group |
| Bystander effect | Diffused responsibility to help + reduced danger-noticing + social cue-taking |
Assimilation vs. Multiculturalism
| Assimilation | Multiculturalism |
|---|---|
| Cultures merge into one | Multiple cultures coexist and are celebrated |
| "Melting pot" | "Cultural mosaic" |
| Slowed by ethnic enclaves | Opposite goal of assimilation |
Common MCAT Trap
- Social facilitation, social loafing, and the bystander effect all describe 'behavior changes around others' — distinguish by mechanism (arousal/evaluation vs. diffused effort vs. diffused responsibility), not just the outcome.
- Groupthink requires active suppression of critical evaluation via desire for harmony — it's not just 'a group made a bad call.' Know Janis's 8 symptoms as concrete vignette signs.
- Polarization and choice shift aren't competing theories — same phenomenon, individual-level vs. group-level.
- A scenario describing cultures blending = assimilation; distinct cultures coexisting/celebrated = multiculturalism — don't reverse these.
Quick Recall
A crowd at a masked riot behaves violently, unlike any individual member normally would. Which phenomenon?
A committee that starts cautious becomes highly risk-averse after discussion. Group polarization or choice shift?
Group members withhold doubts about a flawed plan to preserve consensus. Which Janis symptom?
A community actively encourages and celebrates several distinct ethnic traditions. Assimilation or multiculturalism?
Sign in to unlock this chapter
Biology chapters 1–3 are free. Sign up to unlock every chapter.