Zimbardo's Stanford Prison experiment

• The 'parts' people play as members of various social groups. These are accompanied by expectations we and others have of what is appropriate behaviour in each role.
• E.g. being a parent would show being caring, a student would be obedient.

• Advertised for students and selected student who were deemed 'emotionally stable'
• Study would last for two weeks and participants were paid $15 a day
• Set up a mock prison in the basement of Stanford University psychology department.
• Students were randomly assigned the roles of guards or prisoners
• Prisoners were arrested in their homes to heighten realism of the study, ***** searched, given a uniform and prison numers.
• Prisoners locked in rooms for 23 hours a day, had 16 rules to follow, routines were heavily regulated.
• Prison guards: own uniform including wooden club, keys, handcuffs and sunglasses, went home after shifts. Were told they had complete control over the prisoners. 

• Stopped after 6 days instead of 14
• Threat to psychological and physical health of prisoners
• Prisoners shouted swore at the guards, ripped their uniforms. 
• Guards harrassed prisoners, did frequent headcounts etc.
• Two prisoners suffered nervous breakdown
• One suffered a nervous rash
• One prisoner went on hunger strike - punished by putting him in 'the hole'.
• Was shunned by other prisoners 
• Prisoners began to do as they were told - although it caused them distress. 
• Guards became brutal and aggressive. 

• Conformed to social roles. 
• Deindividualisation - lose sense of identity. Conformed to the norms of the group.

Strengths

• Had control over variables. 
• E.g. choosing emotionally stable participants and randomly assigning roles - rules out personality differences 
• Control over variables = increases internal validity - confident in drawing conclusions.
• Collected data efficiently

Weaknesses

• Lack of realism - Banuazizi and Mohavedi (1975) argued participants were play acting not conforming. 
• Performances based on stereotypes
• Lacks ecological validity - isn't completely realistic
• Unrepresentative - 24 healthy male, middle class, white, college students. 
• Fromm (1973) - Zimbardo exaggerated findings, only 1/3 of guards performed in a brutal manner.  
• Rest tried to help the prisoners, sympathised. 
• beahviour of guards show they're able to exercise right and wrong choices despite situational pressures to conform. 

• Decpetion - Being arrested unexpectedly at home
• Experiment was abandoned after 6 days
• Extensive group and individual debriefings were held
• Benefits gained about understanding human behaviour

• Lack of research support:
• Steve Reicher and Alex Haslam's (2006) replicated the study, found prisoners took control of the prison, guards were subjected to harrassment. 
• Social Identity Theory (Tajfel 1981) - guards failed to develop a shared society identity as a cohesive group, the prisoners did. 
• Prisoners actively identified themselves as members of a social group.