Zimbardo's Stanford prison experiment

Aim:

To identify whether the brutality reported among guards in American prisons was due to the sadistic personalities (dispositional) of the guards or had more to do with the prison environment (situational)

Procedure:

12 male university students who volunteered in response to a newspaper ad
participants were selected based on their physical and mental stability
paid 15 dollars per day
the participants were randomly assigned to one of two social roles, prisoners or guards
turned the basement of Stanford university into a mock prison
‘prisoners’ were arrested by the real local police
prisoners were blindfolded, fingerprinted and strip searched, given an ID number and wore chains around their ankles
guards were given khaki uniforms, reflected sunglasses, handcuffs and a truncheon
guards were instructed to run the prison without any physical violence but had complete power over the prisoners
the experiment was set to run for two weeks

Findings:

Day 1:

prisoners conformed and rebelled
they were punished, they took off their ID
verbally abused by the guards

Day 2-5:

introduced solidarity confinement
guards gradually started to be more threatening
one prisoner had a mental breakdown (this increased everyday)
started to humiliate prisoners (consistent)
sexual humiliation
prisoners were punished for no reason

Day 6:

research stopped
research was supposed to last 2 weeks
someone else told Zimbardo that the research had to stop as there were psychological and physical harm to the prisoners

Conclusion:

Guards, prisoners and researchers (including Zimbardo) all conformed to the roles they were given. They were easily taken on by participants even those who volunteered for a small part of the experiment.