The Most Famous Social Psychology Experiments Ever Performed

What do you do when you know you're right, but the rest of the group disagrees with you? Do you bow to group pressure? In a series of famous experiments conducted during the 1950s, psychologist Solomon Asch demonstrated that people would give the wrong answer on a test in order to fit in with the rest of the group.

In Asch's famous conformity experiments, people were shown a line and then asked to select the line of a matching length from a group of three. Asch also placed confederates in the group who would intentionally select the wrong lines. The results revealed that when other people picked the wrong line, participants were likely to conform and give the same answers as the rest of the group.

While we might like to believe that we would resist group pressure (especially when we know the group is wrong), Asch's results revealed that people are surprisingly susceptible to conformity. Not only did Asch's experiment teach us a great deal about the power of conformity, but it also inspired a whole host of additional research on how people conform and obey, including Milgram's infamous obedience experiments.

Does watching violence on television cause children to behave more aggressively? In a series of experiments conducted during the early 1960s, psychologist Albert Bandura set out to investigate the impact of observed aggression on children's behavior. In his Bobo doll experiments, children would watch a video of an adult interacting with a Bobo doll. In one condition, the adult model behaved passively toward the doll, but in another condition, the adult would kick, punch, strike, and yell at the doll. The results revealed that children who watched the adult model behave violently toward the doll were more likely to imitate the aggressive behavior later on.​

The debate over the degree to which the violence on television influences children's behavior continues to rage on today, so it perhaps comes as no surprise that Bandura's findings are still so relevant. The experiment has also helped inspire hundreds of additional studies exploring the impacts of observed aggression and violence.

During the early 1970s, Philip Zimbardo set up a fake prison in the basement of the Stanford psychology department, recruited participants to play prisoners and guards, and played the role of the prison warden. The experiment was designed to look at the effect that a prison environment would have on behavior, but quickly became one of the most famous and controversial experiments of all time.

The Stanford prison experiment was originally slated to last a full two weeks. It ended after just 6 days. Why? Because the participants became so enmeshed in their assumed roles that the guards became almost sadistically abusive and the prisoners became anxious, depressed, and emotionally disturbed. While the experiment was designed to look at prison behavior, it has since become an emblem of how powerfully people are influenced by situations.

Part of the notoriety stems from the study's treatment of the participants. The subjects were placed in a situation that created considerable psychological distress. So much so that the study had to be halted less than halfway through the experiment. The study has long been upheld as an example of how people yield to the situation, but critics have suggested that the participants' behavior may have been unduly influenced by Zimbardo himself in his capacity as the mock prison's "warden."

Following the trial of Adolph Eichmann for war crimes committed during World War II, psychologist Stanley Milgram wanted to better understand why people obey. "Could it be that Eichmann and his million accomplices in the Holocaust were just following orders? Could we call them all accomplices?" Milgram wondered.

The results of his controversial obedience experiments were nothing short of astonishing and continue to be both thought-provoking and controversial today. The study involved ordering participants to deliver increasingly painful shocks to another person. While the victim was simply a confederate pretending to be injured, the participants fully believed that they were giving electrical shocks to the other person. Even when the victim was protesting or complaining of a heart condition, 65 percent of the participants continued to deliver painful, possibly fatal shocks on the experimenter's orders.

Obviously, no one wants to believe that they are capable of inflicting pain or torture on another human being simply on the orders of an authority figure. The results of the obedience experiments are disturbing because they reveal that people are much more obedient than they like to believe. The study is also controversial because it suffers from numerous ethical concerns, primarily the psychological distress it created for the participants.