Zimbardo:

• What was Zimbardo's procedure?

  • Zimbardo set up a mock prison in the basement of the psychology department of Stanford university
  • Referred to as the Stanford Prison experiment
  • Advertised for students to volunteer and selected 21 who were 'emotionally stable' after extensive emotional testing
  • Randomly assigned to prisoner or guard
  • The 'prisoners' were 'arrested' in their homes by local police and taken to the 'prison'
• More on Zimbardo's procedure?

  • Uniforms, lead to de-individualisation (prisoners: loose smock and cap, identified by their number and never their name. Guards: shirts, mirrored shades, handcuffs)
  • Instructions about behaviour (prisoners: encouraged to identify with their role through tasks and language, for example if they wanted to leave, they had to 'apply for parole'. Guards: reminded they had complete control over the prison)
• Zimbardo-findings:

  • Social roles: parts people play in their social group and the expectations of what is appropriate behaviour in that role; e.g. parent, student, teacher
  • guards conformed to their social roles enthusiastically and treated prisoners harshly
  • Prisoners rebelled within two days, guards retaliated
  • Guards threatened the prisoners psychological and physical health
  • study was stopped after 6 days, instead of planned 14
• Zimbardo- conclusions:

  • social roles have had a strong influence on individuals behaviour. Guards became brutal and prisoners became submissive
  • Social roles were easily taken on by all participants, even volunteers who came in (e.g. prison chaplain)
• What is one strength of Zimbardo's Stanford Prison Experiment (SPE)?


  Control over key variables
• How did Zimbardo and his colleagues ensure control over key variables in the SPE?


  By selecting emotionally-stable individuals and randomly assigning them to roles
• Why was the random assignment of participants to roles significant in the SPE?


  It ruled out individual personality differences as an explanation for behavior
• What conclusion can be drawn if guards and prisoners behaved very differently in the SPE?


  That their behavior was influenced by the roles they were assigned
• How did the control over variables affect the internal validity of the SPE?


  It increased the internal validity, allowing for more confident conclusions about role influence on conformity
• What are the key components of Zimbardo's control in the SPE?


  • Selection of emotionally-stable individuals
  • Random assignment to roles of guard and prisoner
  • Ruling out individual personality differences
• Zimbardo experiment limitation- lack of realism:

  participants were not in a real prison, they were in a lab