9.3: L'esperimento della prigione di Stanford

The famous and controversial Stanford Prison Experiment, conducted by social psychologist Philip Zimbardo and his colleagues at Stanford University, demonstrated the power of social roles, social norms, and scripts.

Social Roles

One major social determinant of human behavior is our social role—a pattern of behavior that is expected of a person in a given setting or group (Hare, 2003). Each one of us has several social roles. You may be, at the same time, a student, a parent, an aspiring teacher, a son or daughter, a spouse, and a lifeguard. How do these social roles influence your behavior? Social roles are defined by culturally shared knowledge. That is, nearly everyone in a given culture knows what behavior is expected of a person in a given role. For example, what is the social role for a student? If you look around a college classroom you will likely see students engaging in studious behavior, taking notes, listening to the professor, reading the textbook, and sitting quietly at their desks. Of course, you may see students deviating from the expected studious behavior such as texting on their phones or using Facebook on their laptops, but in all cases, the students that you observe are attending class—a part of the social role of students.

Social roles, and our related behavior, can vary across different settings. How do you behave when you are engaging in the role of son or daughter and attending a family function? Now imagine how you behave when you are engaged in the role of employee at your workplace. It is very likely that your behavior will be different. Perhaps you are more relaxed and outgoing with your family, making jokes and doing silly things. But at your workplace you might speak more professionally, and although you may be friendly, you are also serious and focused on getting the work completed. These are examples of how our social roles influence and often dictate our behavior to the extent that identity and personality can vary with context (that is, in different social groups; Malloy, Albright, Kenny, Agatstein, & Winquist, 1997).

Social Norms

As discussed previously, social roles are defined by a culture’s shared knowledge of what is expected behavior of an individual in a specific role. This shared knowledge comes from social norms—a group’s expectations of what is appropriate and acceptable behavior for its members—how they are supposed to behave and think (Deutsch & Gerard, 1955; Berkowitz, 2004). How are we expected to act? What are we expected to talk about? What are we expected to wear? In our discussion of social roles, we noted that colleges have social norms for students’ behavior in the role of student and workplaces have social norms for employees’ behaviors in the role of employee. Social norms are everywhere including in families, gangs, and on social media outlets. 

Scripts

Because of social roles, people tend to know what behavior is expected of them in specific, familiar settings. A script is a person’s knowledge about the sequence of events expected in a specific setting (Schank & Abelson, 1977). How do you act on the first day of school, when you walk into an elevator, or are at a restaurant? For example, at a restaurant in the United States, if we want the server’s attention, we try to make eye contact. In Brazil, you would make the sound “psst” to get the server’s attention. You can see the cultural differences in scripts. To an American, saying “psst” to a server might seem rude, yet to a Brazilian, trying to make eye contact might not seem an effective strategy. Scripts are important sources of information to guide behavior in given situations. Can you imagine being in an unfamiliar situation and not having a script for how to behave? This could be uncomfortable and confusing. How could you find out about social norms in an unfamiliar culture?

Zimbardo’s Stanford Prison Experiment

In the summer of 1971, an advertisement was placed in a California newspaper asking for male volunteers to participate in a study about the psychological effects of prison life. More than 70 men volunteered, and these volunteers then underwent psychological testing to eliminate candidates who had underlying psychiatric issues, medical issues, or a history of crime or drug abuse. The pool of volunteers was whittled down to 24 healthy male college students. Each student was paid $15 per day and was randomly assigned to play the role of either a prisoner or a guard in the study. Based on what you have learned about research methods, why is it important that participants were randomly assigned?

A mock prison was constructed in the basement of the psychology building at Stanford. Participants assigned to play the role of prisoners were “arrested” at their homes by Palo Alto police officers, booked at a police station, and subsequently taken to the mock prison. The experiment was scheduled to run for several weeks. To the surprise of the researchers, both the “prisoners” and “guards” assumed their roles with zeal. In fact, on day 2, some of the prisoners revolted, and the guards quelled the rebellion by threatening the prisoners with night sticks. In a relatively short time, the guards came to harass the prisoners in an increasingly sadistic manner, through a complete lack of privacy, lack of basic comforts such as mattresses to sleep on, and through degrading chores and late-night counts.

The prisoners, in turn, began to show signs of severe anxiety and hopelessness—they began tolerating the guards’ abuse. Even the Stanford professor who designed the study and was the head researcher, Philip Zimbardo, found himself acting as if the prison was real and his role, as prison supervisor, was real as well. After only six days, the experiment had to be ended due to the participants’ deteriorating behavior. 

The Stanford prison experiment demonstrated the power of social roles, norms, and scripts in affecting human behavior. The guards and prisoners enacted their social roles by engaging in behaviors appropriate to the roles: The guards gave orders and the prisoners followed orders. Social norms require guards to be authoritarian (such behavior was reinforced; see Haslam, Reicher, & Van Bavel, 2018) and prisoners to be submissive. When prisoners rebelled, they violated these social norms, which led to upheaval. The specific acts engaged by the guards and the prisoners derived from scripts. For example, guards degraded the prisoners by forcing them do push-ups and by removing all privacy. Prisoners rebelled by throwing pillows and trashing their cells. Some prisoners became so immersed in their roles that they exhibited symptoms of mental breakdown; however, according to Zimbardo, none of the participants suffered long term harm (Alexander, 2001).

This text is adapted from OpenStax, Psychology. OpenStax CNX.

C'è un lato oscuro nell'estate del 1971. La polizia ha "arrestato" un certo numero di studenti universitari che hanno risposto a un annuncio che cercava volontari per uno studio psicologico della vita carceraria.

Non sapevano che, nel seminterrato del Dipartimento di Psicologia di Stanford, stavano per imbarcarsi in uno degli studi psicologici più famosi e controversi: The Stanford Prison Experiment, guidato da Philip Zimbardo e colleghi.

Dopo aver compilato un questionario informativo, i partecipanti sono stati assegnati in modo casuale a uno dei due gruppi: i detenuti, che sono stati realisticamente prelevati e registrati dalla polizia, o le guardie, che avevano il controllo diretto dei detenuti.

A seconda dell'incarico, erano vestiti per adattarsi al loro ruolo: un insieme di aspettative che definivano come dovevano comportarsi coloro che si trovavano nella posizione sociale.

Ad esempio, a ogni guardia veniva dato un bastone da notte e un fischietto, insieme a occhiali da aviatore a specchio, per enfatizzare il loro status e la loro autorità.

Inoltre, due ricercatori erano presenti e supervisionavano le operazioni quotidiane: lo sperimentatore principale, Zimbardo, fungeva da sovrintendente della prigione, mentre un altro ricercatore, David Jaffe, era il direttore.

Durante una sessione di orientamento per le guardie, Zimbardo ha delineato vagamente i comportamenti a cui dovrebbero conformarsi, come limitare la libertà dei prigionieri e usare il loro potere per evocare paura e dominare in modo non violento.

In una sessione di follow-up, il direttore ha fornito indicazioni più esplicite per incoraggiare la creazione di un ambiente carcerario, per il bene collettivo dell'esperimento.

Con le autorità penitenziarie sul posto, i prigionieri entravano nella finta prigione, che conteneva tre celle e un armadio per l'isolamento. Venivano spogliati, immediatamente degradati e bendati per confonderli. Inoltre, come parte del ruolo loro assegnato, erano vestite con abiti numerati e berretti con calze di nylon per spersonalizzarle.

Il secondo giorno, i prigionieri iniziarono a ribellarsi bloccando la porta della cella con il letto. Come punizione, il capo della banda fu messo al confino. Questo evento fece precipitare le guardie che ora si rivoltavano contro gli altri detenuti, e il livello di crudeltà aumentò.

Diverse guardie... ma non tutte... hanno migliorato le loro prestazioni per comportarsi da dure, per soddisfare le aspettative preconcette della loro etichetta, il tutto sotto gli occhi vigili del Direttore e del Sovrintendente. Questi leader hanno promosso la durezza come attributo condiviso del conformarsi al gruppo per raggiungere l'obiettivo di esporre la tossicità del sistema penale.

A causa dell'accresciuta e creativa oppressione esercitata sui prigionieri, l'esperimento fu interrotto anticipatamente, dopo sei giorni invece di due settimane.

Alla fine, le guardie si sono comportate in modo stereotipato da duro, sforzandosi di adattarsi alla guida normativa che veniva loro data. A volte, le situazioni tossiche possono tirare fuori il peggio di qualcuno, specialmente nei casi in cui l'individuo si identifica con un leader e la causa collettiva del gruppo.