Brendan Maher reviews two films probing notorious US psychological experiments.

The Stanford Prison Experiment

Director: Kyle Patrick Alvarez. Sandbar Pictures/Abandon/Coup d'Etat: 2015

Experimenter

Director: Michael Almereyda. BB Film/FJ Productions/Intrinsic Value/Jeff Rice/2B: 2015.

Would you rather be a prisoner or a guard? In 1971, many of the 24 volunteers for an unusual psychological experiment at Stanford University in California said that they would prefer the former. “Nobody likes guards,” answered one. Ultimately, a coin flip determined the roles that these students took in the Stanford Prison Experiment, a notorious investigation of obedience and power run by psychologist Philip Zimbardo and commissioned by the US Office of Naval Research. A chilling film of the same name, directed by Kyle Patrick Alvarez, is now on limited release. Meanwhile, Michael Almereyda's Experimenter explores the work of social psychologist Stanley Milgram, whose infamous 1961 experiment on obedience to authority stands as a shocking example of how well-intentioned people can be convinced to harm others. Peter Sarsgaard plays psychologist Stanley Milgram in Experimenter. Credit: Magnolia Pictures

These experiments spanned a decade of US political upheaval. Milgram's was a response to the trial of Adolf Eichmann, one of the prime organizers of the Holocaust, whose unsuccessful defence was that he was following orders. Zimbardo's experiment took place as reports of atrocities by US soldiers filtered back from the Vietnam War. Interpretations have long been debated, but both experiments haunt the imagination by putting extreme behaviour on display.

The Stanford Prison Experiment is stark and claustrophobic, much like the makeshift 'prison' that Zimbardo and his colleagues constructed in the Stanford psychology department's basement. The screenplay is adapted from Zimbardo's The Lucifer Effect (Random House, 2007), which aimed to explain how situations and group effects can bring about evil behaviours. The film traces the experiment from volunteer recruitment until day six, when Zimbardo, concerned for the prisoners' well-being, shut it down prematurely.

A handful of documentaries have explored the study's findings and legacy, but Alvarez captures something intimate and atmospheric that cannot be gleaned from grainy videos or interviews. The 1970s are certainly there: the hair, the polyester and the lax research oversight. There are also subtle emotional moments, such as when cocksure humour drains from the face of 'prisoner 8612' as he is instructed to strip naked for delousing. Tensions rise between 'guards' and 'prisoners' in The Stanford Prison Experiment. Credit: Steve Dietl/IFC Films

Zimbardo intended to explore how prisoners adapt to powerlessness, but he has contended that the experiment demonstrates how swiftly arbitrary assignment of power can lead to abuse. It has been invoked as paralleling the harm done to Iraqi detainees at the US-run Abu Ghraib prison in 2003: several guards in the film verbally taunt prisoners, restrict access to basic necessities and resort to sexual humiliation. One guard, nicknamed John Wayne, adopts the affect and southern drawl of the sadistic prison captain in the 1967 film Cool Hand Luke, preying undeterred on the weaknesses of 8612 in particular.

The prisoners, at first rebellious, are broken by the guards and pitted against one another; the experimenters themselves lose perspective. When 8612 begs to be released, Zimbardo and his colleagues initially refuse, convinced that he is faking his distress — even though that should not override the voluntary nature of the experiment. Several subjects, all screened as emotionally well grounded, have breakdowns; rather than fear for their well-being, Zimbardo develops a paranoid belief that outside forces will shut “his prison”. Finally, psychology PhD student Christina Maslach (later Zimbardo's wife) persuades him to change his mind after seeing the prisoners, half-naked and chained together, with bags over their heads, on a trip to the toilet. She tells Zimbardo: “Those are boys, and you are harming them.” The next day, as guards force prisoners to pantomime sexual intercourse, Zimbardo tells them that it is time to go home.

The film pulls few punches regarding Zimbardo's behaviour. This is consistent with his confession, in The Lucifer Effect, that he failed to provide “adequate oversight and surveillance when it was required ... the findings came at the expense of human suffering”. He wrote, “I am sorry for that and to this day apologize for contributing to this inhumanity.” The study was subsequently deemed to fall within existing ethical guidelines.

Others have wondered, however, whether Zimbardo oversold the results. When I contacted the real-life 'John Wayne', Dave Eshelman, he said that the experiment reveals no generalizable truths about humans' propensity for evil, and that he was playing a part, running his own experiment to see how far he could push people. “I figured I was doing them a favour by trying to force some results.” At least one other guard has said that Zimbardo went out of his way to create tension.

Milgram, too, has a complex legacy, as Experimenter reveals. Through an imaginative structure, the film explores several of his contributions to behavioural psychology. But he is best known for his electroshock experiments at Yale University in New Haven, Connecticut, a decade before Zimbardo's experiment. In them, an authority figure asked volunteers to administer what they were told were increasingly painful electric shocks to an actor who they believed was another volunteer. Two-thirds maxed out the voltage despite the actor's anguished cries.

It was difficult for many to come to terms with the results — including some of the research subjects, who were unhappy about the deception (Milgram preferred “illusion”). Almereyda playfully gives the audience a backseat view of the psychologist's approach. There are scenes in which Peter Sarsgaard, playing Milgram, speaks directly to camera — an homage to Milgram's own films explaining his experiments. This is a work, as the title implies, much more about the experimenter than about the experiment. Zimbardo has spoken of meeting Milgram, who “embraced me and said, 'I'm so happy you did this because now you can take off some of the heat of having done the most unethical study'.”

The shared legacies of the researchers can be seen in updated regulations for psychological research on human subjects, which prevent the kind of deception that Milgram perpetrated and the unstructured opportunity for abuse that Zimbardo created. But their experiments will always hold captive a dark part of the human imagination as we wonder just what kind of pain we would be willing to inflict on other human beings.

Author information Affiliations Brendan Maher is biology features editor at Nature. Additional reporting by Monya Baker. Brendan Maher Authors Brendan Maher View author publications You can also search for this author in PubMed Google Scholar

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