Glossary
Group Polarization
What is group polarization?
Group polarization is a shift after group discussion toward a more extreme version of the group’s initial average tendency. The shift can favor greater caution as well as greater risk. It does not require every individual to change equally.
How Group Polarization Can Happen
Discussion can introduce more arguments supporting the position a group already favors. Social comparison offers another explanation: people adjust their position in relation to others and the views valued by the group. These are possible explanations to investigate; neither can be assumed to explain why a particular group became more extreme.
Research Foundation
Myers and Lamm’s 1976 review synthesized evidence across several judgment tasks and considered informational and social-comparison explanations. The phenomenon is different from two opposing groups simply remaining far apart.
Research example
In a simulated-jury experiment, discussion of hypothetical cases strengthened average judgments toward innocence for low-guilt cases and toward guilt for high-guilt cases. The same shifts did not occur for cases that were not discussed.
Why It Matters
Agreement after a meeting does not necessarily mean that the group found a better answer. It may mean that discussion strengthened its starting position. That is worth checking when a team treats growing confidence as evidence of growing accuracy.
Limits
This result concerns simulated decisions, not a universal prediction about juries or political debate. Whether a shift improves accuracy or causes harm requires evidence about the decision itself. Polarization is not automatically groupthink, and discussion does not always produce it.
Group polarization vs. groupthink
Group polarization describes the direction of a shift in views. Groupthink concerns pressure for agreement that weakens the examination of alternatives. A group can move toward a more extreme position without suppressing disagreement; the two labels ask different questions about the discussion.