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Famous Psychological Experiments

Famous Psychological Experiments

Author: Erick Taggart

Identify classic research studies, and the ethical issues involved.

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Source: Milgram experiment: public domain;

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Hello class. In today's lesson, we're going to examine two famous psychological studies. And these are ones that might be familiar to you. So we're going to look at them in terms of the experimental method. So I want you to think about all the things that go into making an experiment, things like variables, methods, analysis, and the results of an experiment, as well as potential sources for bias. And I also think that you probably enjoy learning about some of the methods and results. Because these are two pretty interesting ones. They're famous for a reason.

So the first one we'll talk about is Milgram Obedience Experiments. And these were originally created as a result of World War II, when people thought that the Germans that went along with what the Nazis had done in Germany during World War II we're also responsible, they were morally wrong in what they did. And they also thought that this was really abnormal. People wouldn't go along with these sorts of things under normal conditions.

So the purpose of this experiment was to see how people respond to authority, and whether they would obey doing what they're told even if what they were told is something that's not necessarily morally right. Here's how it worked. So a subject was placed in a room with an experimenter next to them. They were the authority figure. And in front of the subject was a control panel with different buttons. Each button had a different voltage on it in increasing order, 15 volts up, up to 450 volts. They were also given a list of word pairs.

Now, they were told that that panel with all the different voltages were hooked up to another participant in a different room, that they could hear but that they couldn't see. And that person would try to memorize the list of word pairs as it was read to them by the subject. The subject would then ask the first word in a word pair and see if they could get the correct answer from the other participant. If they got it wrong, then the subject would press the button and give them a shock.

And they would do this in later order as it would get more and more powerful, until they finally got to 450 volts. And the important thing to know is there actually was no other second subject. It was just a recording. So the responses they were getting were the same in each experiment regardless of what the person said or did. And they would generally get the answers wrong.

So they wanted to see would the people continue to shock a person, particularly with the authority figure right next to them? Well, the results were that the subjects would continue to give the electric shocks regardless of the increasingly angry or worried responses they were getting from the recording that they heard. If they questioned what they were doing, then the experimenter would give them a series of responses. Things like you have to continue. If they continued to question or they refused to go on, then the experiment would stop.

But if they went all the way to 450 volts three times, then that would also be the end of the experiment. So the question was how many people would continue to go on even if at the very end they were worried for the person's safety on the other side? Well, the results were that 66% of people went all the way through, which shows what a powerful affect that authority can have and the push to obey on people's choices, even who are considered to be normal people.

Now, the Stanford Prison Experiment was a psychological experiment done by Philip Zimbardo at Stanford in 1971. And this is where participants that were taken from a pool were randomly grouped into categories of either prisoners or guards. And they were locked onto a floor of a building that was a simulated prison for a two week period. That was the goal. The purpose was to see how normal people responded to prison conditions. How environment influences our behavior. But also it was looked to see how people responded to roles that are associated with different groups.

For example, would they fall into a prisoner role or a guard role depending on what they were labeled, regardless of if they were to begin with. So the prisoners, as a result, the first day as well as the guards started to fall into these different roles. And they started acting like it was an actual prison situation, even though none of them were actually prisoners or guards. The prisoners after the first day or into the second one began to act out against the guards. They start refusing to follow directions. They refused to come out of their cells. And they revolted against the guards.

During the second day, one prisoner began to act what they called crazy. They started yelling, going into anger, into fits of rage, and couldn't be controlled. The guards, on the other hand, started to impose measures and countermeasures in response. They started creating what was called a privilege cell, for people to didn't act up. And they made prisoners go to the bathroom in buckets in the cells. They force them to do push ups. And they took away their mattresses so they had to sleep on the floor.

Towards the end, one prisoner spoke out against the conditions and refused to eat. He went on a hunger strike. And then the guards placed him into a solitary confinement cell. Even Zimbardo, who is the experimenter, began to get into his role as the superintendent of the prison. And he continued to allow the abuse. It only actually lasted for six days before the conditions became so extreme and they began to worry for the health of the participants and it was shut down.

And it resulted in major psychological and almost physical harm to the participants. So the results weren't necessarily conclusive, because it didn't go on for the full two weeks. But it definitely showed the powerful effect that a prison type environment can have as well as the different labels and roles of guard or prisoner on people. So both of these experiments led to a more specific and stringent need for ethical guidelines to guide experimental practices. And these are put in place today by the American Psychological Association or APA.

Notes for "Famous Psychological Experiments"

Terms to Know

Milgram Obedience Experiments
A series of experiments after World War II that attempted to measure how people respond to authority, or obey what they are told.

Complying to the request of an authority figure.

Stanford Prison Experiment
A psychological experiment in 1971 where participants were randomly grouped into categories of prisoners and guards and locked into a floor of a building for only 6 days before it was canceled.

Terms to Know
Milgram Obedience Experiments

A series of experiments after World War II that attempted to measure how people respond to authority, or obey what they are told


Complying to the request of an authority figure

Stanford Prison Experiment

A psychological experiment in 1971 where participants were randomly grouped into categories of prisoners and guards and locked into a floor of a building for only six days before it was canceled