Zimbardo's prison experiment

What was the aim of Zimbardo's 'Stanford Prison Experiment?'

To investigate how readily people would conform to the roles of guard and prisoner in a role-playing exercise that simulated prison life.

When (year) was the study conducted?

1973

Who were the participants?

21 male college students (chosen from 75 volunteers) that were screened for psychological normality.

How were the roles of the participants assigned?

Random allocation to either the prisoner or guard role.

Initially, what happened to the participants who were allocated to the 'prisoner' role?

Prisoners were arrested at their own homes, without warning, and taken to the local police station where they were fingerprinted, photographed and 'booked'.

Initially, what happened to the participants who were allocated to the 'guard' role?

Guards were issued with a khaki uniform, whistles, handcuffs and dark sunglasses (to make eye contact with prisoners impossible).

What happened when the prisoners arrived at the prison?

The prisoners were stripped naked, deloused, had all their personal possessions removed and locked away, and were given prison clothes and bedding. They were referred to by serial number only.

How did the 'guards' begin to behave?

The 'guards' began harassing the prisoners.

They taunted and insulted the prisoners and gave them boring and pointless tasks to accomplish.

They had begun to dehumanise the prisoners.

How did the 'prisoners' begin to behave?

The 'prisoners' talked about 'prison issues'

told tales on each other to the guards

some sided with the guards against other prisoners.

What happened to a 'prisoner' 36 hours into the experiment?

He had to be released because of uncontrollable bursts of screaming, crying and anger which indicated he may be entering the early stages of deep depression.

How long did Zimbardo intend the experiment run for? How long did it actually last?

Zimbardo intended the experiment to run for a fortnight but on the sixth day he closed it down.

What was the conclusion of the study?

People will readily conform to the social roles they are expected to play, especially if the roles are as strongly stereotyped as those of the prison guards. The roles that people play can shape their behaviour and attitudes.

What are some ethical criticisms of the study?

-lack of fully informed consent (as Zimbardo could not have predicted what was to happen)

-level of humiliation and distress experienced by 'prisoners'

-'prisoners' were not protected from psychological and physical harm