Zimbardo's research into conformity to social roles

KEY Yellow = important info Pink = additional info Red = Key findings
-22 participants selected from the 75 who responded to a newspaper advert, chosen through ones seen as 'most stable' during interviews.
-Random allocation of roles 10 'prisoner's and 11 'guard's (1 participant decieded not to follow through with the study).
-Basement of Stanford University converted into a 'prison'
-Prisoners fake arrested at their homes, blindfolded and fingerprinted, taken to prison where they were stripped and deloused, issued with prison clothing.
-Prisoners wear smocks, rubber flip-flops, and stocking on head to mimic shavin head. Had a light chain around their ankle.
-Guards wear knaki shirts and trousers with a peaked cap (uniform), reflective sunglasses (mask their identity) and carried a baton and whistle (authority).
-Clothing emphasised roles, guards are in a military role, with baton as a sign of control. While prisoners were designed to be humiliating.
-Photographed and placed into 3 cells
-Addressed prisoners by numbers over their names
-Zimbardo and two other co-researchers observed, audio and video recorded both the guards and prisoners behaviour. Each was also interviewed during the study, then again after the study had ended.

-Huge and almost instantaneous effect on behaviour of both groups
-Social interactions within and between (inter and intra) the groups led to these changes
-Prisoners increasingly passive
-Guards increasingly verbally hostile
-After day one, prisoners exhibited symptoms of stress
-A baracade made by some prisoners to lock themselves in their cell was broken up by fire extinguishers, they were punished by being stripped of clothing and bedding.
-Within 4 days, 4 prisoners realsed with signs of extreme emotional disturbance
-5th day a 5th release due to a psychosomatic rash
-Study terminated on 6th day, morality of experiment questioned by Christina Maslach, a Stanford Ph.D graduate( who had come to conduct interviews with participants), after she witnessed the abuse of the guards on the prisoners.

- Demand characteristics could explain the findings of the study. Most of the guards later claimed they were simply acting. Because the guards and prisoners were playing a role, their behavior may not be influenced by the same factors which affect behavior in real life. This means the study's findings cannot be reasonably generalized to real life, such as prison settings. I.e, the study has low ecological validity.

+ However, there is considerable evidence that the participants did react to the situation as though it was real. For example, 90% of the prisoners’ private conversations, which were monitored by the researchers, were on the prison conditions, and only 10% of the time were their conversations about life outside of the prison. The guards, too, rarely exchanged personal information during their relaxation breaks - they either talked about ‘problem prisoners,’ other prison topics, or did not talk at all. The guards were always on time and even worked overtime for no extra pay. When the prisoners were introduced to a priest, they referred to themselves by their prison number, rather than their first name. Some even asked him to get a lawyer to help get them out.

- The study may also lack population validity as the sample comprised US male students. The study's findings cannot be applied to female prisons or those from other countries. For example, America is an individualist culture (were people are generally less conforming) and the results may be different in collectivist cultures (such as Asian countries).
+ A strength of the study is that it has altered the way US prisons are run. For example, juveniles accused of federal crimes are no longer housed before trial with adult prisoners (due to the risk of violence against them).
+Another strength of the study is that the harmful treatment of participant led to the formal recognition of ethical guidelines by the American Psychological Association. Studies must now undergo an extensive review by an institutional review board (US) or ethics committee (UK) before they are implemented. A review of research plans by a panel is required by most institutions such as universities, hospitals, and government agencies. These boards review whether the potential benefits of the research are justifiable in the light of the possible risk of physical or psychological harm. These boards may request researchers make changes to the study's design or procedure, or in extreme cases deny approval of the study altogether.