The Asch conformity experiments were a series of social psychology experiments run in the 1950s to explore group dynamics and the pressure to conform in groups. Solomon Asch set up an experimental design at Swarthmore College where a subject was surrounded by a group of confederates who exerted varying degrees of pressure to encourage the subject to answer an objective question incorrectly. Asch found that with enough pressure, people would choose the wrong answer, but small changes to the dynamics could have a radical impact.
In the experiment, subjects were seated around a table with room for eight people, and were told that the experiment was about visual acuity. Asch presented the participants with a series of pictures of lines and asked them to make objective statements to the group about line length and comparisons. The twist in the Asch conformity experiments is that only one of the eight people was actually a study subject. Everyone else in the Asch conformity experiments was actually a research confederate.
When the confederates all answered correctly, the research subjects easily offered the correct answer. If one or two confederates offered the wrong answer, subjects would usually answer correctly, but when three or more, or the entire group, insisted on a wrong answer, subjects would often give the wrong answer. The Asch conformity experiments showed that peer pressure could force people to give a wrong answer even when they knew the right answer.
The experiment got particularly interesting when Asch added in a dissenting minority. If the confederates gave different answers, it encouraged the subject to speak up and offer the correct answer. He used this to illustrate that even a single voice in opposition can have a powerful impact, and may give other people the courage to speak up, even with different answers or ideas. The dissenting confederate could give another incorrect answer, for instance, and the subject would still answer correctly.
Analysis of the Asch conformity experiments provided important information about how groups work and how members of a group can pressure each other. Peer pressure plays a critical role in group dynamics, from the playground to the astrophysics research facility. Asch worked in an era when numerous social psychologists were starting to experiment with the pressures that can affect group behavior. Stanley Milgram experimented in the 1960s with how far people would go when ordered by an authority figure, for instance, while Philip Zimbardo ran the infamous Stanford Prison Experiment in the 1970s.