Psychology: Development psychology: Transmission of aggression through imitation of aggressive models

Psychology: Development psychology: Transmission of aggression through imitation of aggressive models

Authors: Bandura et al. (1961)

Key term: Aggression

Background/context: Behaviorists believe that all behavior is learned, through classical conditioning (Pavlov - learned through association) and operant conditioning (Skinner - learned through reward and punishment). Watson (1923) classically conditioned 'Little Albert' to be scared of a white rat.

Behaviorists believed that we could only learn things that happened to us personally. But Bandura outlined observational learning - if behavior of a model (parent, teacher, etc) is observed then it will be copied (imitation learning). To test this theory Bandura designed an experiment trying to teach children aggression through observation.

Aim/Hypothesis: Children would reproduce aggressive behavior even if the model was no longer present

1. If a behavior is observed it will be imitated.
2. If a behavior is not observed it cannot be imitated.
3. Boys will copy a male model more than a female model/ Girls will copy a female model more than a male model.
4. Boys are more predisposed to show aggression than girls.

Method: Laboratory experiment - controlled observation 

Variables:

• Independent variables:

1. Three conditions:
   -Aggressive model group - 6 boys and 6 girls with the male model; 6 boys and 6 girls with the female model.
   -Non-aggressive model group - 6 boys and 6 girls with the male model; 6 boys and 6 girls with the female model.
   -Control group - 12 boys and 12 girls who saw no model at all.
2. Sex of model
3. Sex of child

• Dependent variable: Number of behaviors out of 240 maximum in each response category.

Independent variable conditions

Design: Matched pairs - Children were matched for pre-existing aggression levels of aggression, and independent groups as shown in 3 conditions above.

Participants and sampling technique: 

• 72 children (36 boys and 36 girls) aged between 37(just over 3 years) to 69 months (5 years 9 months) from Stanford University nursery school.
• Mean age was 52 months (4 years 4 months)
• Probably opportunity sample
• Quota sampling to achieve 12 participants in each sub-category

Apparatus: 

• Room 1: Potato prints, picture stickers, table and chair, Tinker toy set, mallet and inflatable 5-foot bobo doll (adult-size)
• Room 2: Fire engine, locomotive (train), doll, spinning top
• Room 3: One-way mirror for observations, 3-foot bobo doll, mallet and peg board, two dart guns, tetherball with a face, tea set, 3 bears, cars, farm animals, crayons and coloring paper.

Bobo doll

Controls:

• Children were matched for pre-existing aggression levels by the experimenter and nursery teacher independently rating 51 children on a scale of 0 - 5 (5 being very aggressive). There was very good agreement between the teacher and experimenter (0.89).
   -eg. A child rated as 5 (very aggressive) was matched with another child rated 5 (with one going to the 'aggressive' condition and one going to the 'non-aggressive' condition).
• The toys in room 1, 2 and 3 were always the same and always in the same position when a child entered the room. 
• The actions of the aggressive model was always the same, in the same order and for the same length of time. 
• Observers watching through the two way mirror were unaware of which condition the child was in while observing to prevent bias.
• The 20 minute session was divided into 5 second intervals, giving 240 response 'units'. 
• Observers had a inter-rater reliability rate in the 0.9 range.

Procedure:

1. Each child was shown to room 1. He/She played with the potato prints and stickers to settle in. 
2. The child was taken to the other side of the room where they were shown to either of the two conditions for 10 minutes: aggressive or non aggressive.
    -Aggressive condition: Model would sit on, throw the bobo doll (Verbal aggressive: "throw him in the air") punch in the nose ("sock it on the nose"), hit the bobo doll with the mallet ("hit him down") and kick the bobo doll around the room ("kick him").
    -Non-aggressive condition: Adults assembled toy and did not interact with the bobo doll.
    -Control condition: No adult in the room.
3. Child was then taken to room 2 for Mild aggression arousal (to annoy children and increase aggressive behavior). He/She played with the toys for around 2 minutes before the toys got taken away from the child and he/she was told they were not allowed to play with anymore as they were "the very best toys" and had been reserved for other children.
4. Testing for delayed imitation. Room 3 (test room) contained non-aggressive and aggressive toys (eg. dart guns - aggressive gun play). The experimenter was in the room occupied with paperwork, while two observers watched through a two way mirror. Children were observed playing for the next 20 minutes.

Results:

• Results were in 6 response categories for both female and male children:
  - Imitative physical aggression
  - Imitative verbal aggression
  - Mallet aggression
  - Punches bobo doll
  - Non-imitative aggression
  - Aggressive gun play
• Imitative aggression: Physical and verbal aggression to that modeled in the procedure
• Non-imitative aggression: New aggressive acts not demonstrated by model
• Quantitative data

Results table

• Significant results:
  Male imitative physical aggression with male model: 25.8
  Female imitative verbal aggression with female model: 13.7
  Male mallet aggression with male model: 28.8
  Male Non-imitative aggression with male model: 36.7

Findings:

• Significantly more instances of aggression in the aggressive group than the non aggressive group.
• Boys followed the male model more when it came to physical aggression.
• Girls followed the female model more in verbal aggression.
   This may be because since a young age we are taught that men are meant to be more masculine.
• Children in all groups, boys and girls, showed aggressive gun-play even though this was not observed in Room 1 (exposure) - non-imitative aggression.

Conclusion: Behavior that is observed is likely to be imitated - Bandura's 'observational learning' theory is supported. 

Strengths:

• Laboratory experiment - High levels of control - Reliable, can be redone, EVs rare
   -Same toys in the same position for each child
   -Models did the same procedure for each condition for each child
   -All variables besides conditions in the IV controlled
   -Observers did not know which condition they were recording results for, so no bias.
•  -Standardized procedure, can be repeated again to test for reliability of results
• Valid - IV directly affects DV - Observation of models determining child's level of aggression
• Quantitative data - Objective, can be analysed
   -Number of responses marked for each response category to show aggression in children clearly shows that the children who experienced the aggressive condition show more aggression.

Weaknesses:

• Laboratory experiment - Lacks mundane realism - Not normal daily life activity
   -Children do not usually sit there and watch adults play without joining in
   -Children and model are strangers
   -Child and model do not interact
• Quantitative data - We don't know why the children chose to be aggressive
• Snapshot study - Results recorded immediately after experiment, which was also a single experiment - can one experience cause long term effects?

Ethics: 

• Use of children in experiments is unethical because they cannot give consent
• This experiment could have left long term psychological damage on the children
• Children left the experiment psychologically different then before the experiment