Health & Medicine

The Stanford Prison Experiment: Dr. Philip Zimbardo Looks Back On The Controversial Psychological Study

Kathleen Lees
First Posted: Jul 17, 2015 02:32 PM EDT

In 1971, 24 college students from Stanford University willingly participated in one of the most revealing yet controversial psychological experiments of all time – The Stanford Prison Experiment. The experiment demonstrated how the behavior of decent, ordinary people could be altered – how a "perfect storm" of certain factors can serve to manifest humanity's darker impulses.

Forty-four years since the experiment first took place, a new movie on the study is hitting the big screen beginning July, 17. The drama stars Billy Crudup of "Almost Famous," as the lead investigator, Philip Zimbardo. (A German movie was also made about the study in 2001, and a 2010 take starred Forest Whitaker and Adrien Brody.)

Zimbardo noted how the idea for the experiment had initially come from earlier research done by his high-school classmate, Stanley Milgram.

"His study was the first to demonstrate the power of situational forces over moral conscience," Zimbardo told SWR.

Milgram's research, also known as the Milgram Experiment, which was conducted at Yale in 1961-1962, aimed at determining how many volts of electricity a subject would administer to someone else, another research participant, on the orders of an authority figure. His experiments began just a year after the trial of Adolf Eichmann in Jerusalem, and addressed questions such as "Could it be that Eichmann and his million accomplices in the Holocaust were just following orders? Could we call them all accomplices?"

For his groundbreaking experiment, Milgram recruited 40 male participants between the ages of 20 and 50 who were paid $4.50 to take on the role of learner or teacher. Learners were strapped to chairs and hooked to electrodes as they attempted to master a list of word pairs. "Teachers" tested the learners by naming a word and then asking the learner to recall its pair from a list of possible choices. An authority figure ordered a teacher to administer an electric shock every time a learner made a mistake, increasing the intensity of the shocks each time.

Study results from the Milgram Experiment revealed that when prompted repeatedly to shock learners, 65 percent (or two-thirds) of the teacher participants continued onward to the highest level of shock: 450 volts, and all participants continued to 300 volts. The takeaway from Milgram's experiment is that ordinary, "everyday" people are extremely likely to follow an authority figure – even, perhaps, to the extent of killing another human being. In other words, obedience to authority seems to be ingrained.

A decade later at Stanford, Zimbardo famously studied similar psychological effects with his own experiment in which students took on the role of prisoner or prison guard.

Out of 75 respondents, Zimbardo selected a team of 24 males whom he deemed the most psychologically stable and healthy. Zimbardo recalls just how the participants – all willing, middle-class, college students – came into their roles, which had been chosen based on a simple coin-flip.

While Zimbardo took on the role of superintendent and an undergraduate research assistant took on the role of warden, he conducted his experiment which was designed in order to induce disorientation, depersonalization and deindividualization in the participants.

The first 24 hours of the experiment were uneventful; soon afterward, however, the students really began to take on their designated responsibilities and roles. The basement-turned-prison of Jordan Hall in Stanford's Psychology building showcased how different circumstances can influence behavior – so much so that the harsh and disturbing interactions between the "guards" and "prisoners" forced the experiment to be cut down to just six days from the original 2-week goal.

"We live our lives in groups, in institution settings and we play roles. And we're unaware of how we become the role," Zimbardo says. "In this experiment, I essentially wanted to create a situation like that."

"So one question is, 'What happens if you fill a bad place with only good people? Do the good people change the bad places?' The answer is obviously that they should. But the other question is, 'Does the bad place win and humanity lose?'" Zimbardo adds. "In this experiment, the answer is the second. A bad place dominated the behavior of the majority of good people in it."

Zimbardo discusses more on what he's coined as the "Lucifer Effect," in his book "The Lucifer Effect: Understanding How Good People Turn Evil," which summarizes the Stanford Prison Experiment and how and why transformations exemplified by his experiment, take place, in addition to what they can tell us about recent events, including the Abu Ghraib prisoner abuse in Iraq and police brutality within the United States.

SWR also spoke with Bruce D. Bartholow, a psychology professor at the University of Missouri-Columbia who focuses on personal perception and interpersonal expectancy effects, environmental predictors of aggression and the correlates and consequences of alcohol abuse.

"They kind of fell into the role that they thought, stereotypically, was expected of them," Bartholow says, recalling how one of the guards in the experiment chose to wear aviator sunglasses as part of his character. "What I remember about this most, is that later, when they were interviewing the prisoners, he was described as the most cruel."

Bartholow went on to reference the recent accounts of police brutality in Ferguson, Mo., where, following the shooting of Michael Brown in August, 2014, a level of unrest presently remains between residents and the police. 

"The way things have evolved, there's more distinctions in the community with police," Bartholow says, noting how some officers wear militaristic-like gear, sometimes even making it difficult to completely see their faces due to the helmets and visors they wear.

"And one of the reasons it's always assumed that people would do things in mobs or riots like they wouldn't do as individuals is because they feel anonymous. They feel like they're part of something bigger than themselves and they can't be individually identified."

Remarkable, however, there are those of us – even in circumstances of great hardship and despair, suffering through traumatic events that one would expect to transform any seemingly stable, "good" person – who find the strength to resist what's happening around them. They combat their darker impulses and chose to stand up and speak out. 

"What's clear is that in all research on situational forces in real-life situations – war, Holocaust, etc. – there's always a minority that resist," Zimbardo says. "And, in some cases, these people even persuade others to join them. We might even think of them as heroes."

This is what Zimbardo is working on now through the Heroic Imagination Project (HIP), a nonprofit organization that aims to better understanding the nature of everyday heroism and the psychology of personal and social growth.

"I started the Heroic Imagination Project in San Fransisco as a way of teaching young people how to stand up, speak out and take effective action in all challenging situations," Zimbardo says. "So I've gone through a personal transformation of creating evil to inspiring heroism."

But questions still remain. For instance, what might cause certain people to go against the grain? To stay strong in a bad situation whenever others around them cannot?

"We just don't know yet because there's very little research on heroism," Zimbardo says. "But what we do know is that the hostile situation that makes some villains also provides opportunities for others to instill the heroic imagination."

"The Stanford Prison Experiment" comes out today and is rated R (Under 17 requires accompanying parent or adult guardian) for language and intensity.

You can learn more about the movie in this YouTube trailer.

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