THE BOBO DOLL EXPERIMENTS

BANDURA’S SOCIAL MODELLING APPROACH TO AGGRESSION

Theoretical Background BEHAVIOURISM Focus on the observable (behaviour) All that cannot be observed is ignored Nearly all behaviour is learned Focus on experimentation rather than

speculation Environmental determinism: tabula rasa,

little importance attached to genes Animal research can be generalized to

humans

Classical Conditioning• PAVLOV• Stimulus-

Response (S-R)

Operant Condicioning• SKINNER• Reinforcement

(+,-) & punishment

Social Learning Theory• BANDURA• Stimulus-

Observation-response (S-O-R)

Theoretical Background /BEHAVIOURISM

HYPHOTHESIS

MAJOR HYPOTHESIS

H1. Participants exposed to aggressive models will reproduce aggressive acts resembling those of the models to a significantly greater extent than both participants exposed to non-aggressive models and those not exposed to any models at all.

HYPHOTHESIS

SECONDARY HYPOTHESIS

H2. Participants exposed to subdued, non-agressive models will display significantly less imitative aggression than control group participants (i.e. those who are not exposed to any models at all)

H3. participants will imitate the behaviour at same sex models to a greater degree than opposite sex models.

H4. Boys will be more likely to imitate aggression than girls, especially when they are exposed to aggressive male models

DESIGNVARIABLES

Independent

Variable•Exposure to aggressive model or non-aggressive model

Dependent

Variable•Imitation / behaviour after the exposure

Response measures

Imitation of physical aggression

• This category included acts of striking the Bobo doll with the mallet, sitting on the doll and punching it in the nose, kicking the doll, and tossing it in the air.

Imitation of verbal aggression

• Subject repeats the phrases “sock him”, “hit him down”, “kick him”, “throw him in the air”, or “pow”.

Imitation of non-aggressive verbal responses

• Subjects repeat, “he keeps coming back for more”, or “he sure is a tough fella”.

DESIGNPARTICIPANTS / 36 girls & 36 boys from Stanford Nursery

mean age: 4 years and 4 months

Total72 boys and girls

Aggressive condition24

Control24

Non-aggressive condition24

Experimental DESIGN Matched pairs design

- all the kids where matched for their normal levels of aggressive behaviour in the nursery school

Physical aggression Verbal aggression

Experimenter and Nursery school teacher

- the kids where arranged in groups of 3 then, assigned randomly to one of the two experimental conditions or the control group

Experimental DESIGNControl group

24

NON-AGGRESSIVE CONDITION

Participants

male female

Model male 6 6

female 6 6

AGGRESSIVE CONDITION

Participants

male female

Model male 6 6

female 6 6

RESULTS

Scores of children in the aggressive condition where significantly higher than those of either the non-aggressive or control groups

H1. supported or rejected?

RESULTS /mean aggression scores for experimental and control subjectsResponse category

Experimental groupsAggressive Non-aggressive Control

GroupsF model M

modelF model M

model

Imitative physical aggression Female subjects Male subjects

5.512.4

7.225.8

2.50.2

0.01.5

1.22.0

Imitative verbal aggression Female subjects Male subjects

13.74.3

2.017.2

0.31.1

0.00.0

0.71.7

Mallet aggression Female subjects Male subjects

17.215.5

18.728.8

0.518.7

0.56.7

13.113.5

Punches Bobo doll Female subjects Male subjects

6.318.9

16.511.9

5.815.6

4.314.8

11.715.7

Non-imitative aggression Female subjects Male subjects

21.316.2

8.436.7

7.226.1

1.422.3

6.124.6

Aggressive gun play Female subjects Male subjects

1.87.3

4.515.9

2.68.9

2.516.7

3.714.3

RESULTSH1 confirmed

Subjects in the aggression condition reproduce a good deal of physical and verbal aggressive behaviour

h1

H2 rejectedNo significant differences were found between non-aggressive and control groups

h2

H3 confirmedSubjects imitate more when the aggressive behaviour was done by the same sex model

h3

H4 partially confirmedBoys reproduced more imitative physical aggression than girls but no more imitative verbal aggression

h4

DISCUSSION

Social imitation may hasten or short-cut the acquisition of new behaviours without the necessity of reinforcing successive aproximations.

The fact that subjects expressed their aggression in ways that clearly resembled the novel patterns exhibited by the models, provides striking evidence for the occurence of learning by imitation.

Imitation was found to be differentially influenced by the sex of the model with boys showing more aggression than girls following exposure to the male model, the difference being particularly marked on high masculine-typed behaviour.

ACTIVITY

EVALUATION theoretical issues subsequent research methodological issues aplications and implications

TRANSMISSION OF AGGRESSION THROUGH IMITATION OF AGGRESSIVE MODELSEVALUATION OF THE EXPERIMENT – 1PSY

Theoretical issues Subsequent research

Methodological issues

Applications and implications

People only aggres under appropiate social conditions which facilitate such behaviour:Behaviour is learned.

1) Bandura, Ross & Ross: 4 year old watched 2 films involded aggression betweem 2 men. 1st video: aggressive model won. 2nd video: the agressor was beaten up.

Children exposed to a new toy act differently than children who have been previously exposed to the toy –familiarity.

Mass media has an important rol, children will imitate this behavior (specially aggressive).

Learning may occur without any reinforcement; exposure to a behaviour is sufficient for learning (Bandura)

R&R Results:1st video: participants imitated aggression. 2nd video: participants imitated non aggression. The control group in the middle of both.Did they learn or only reproduce aggression?

The behavior performed by the adult is very bizarre, it is very unlikely that an adult will act like that in front of a child.

Physical punishments are the demonstration of the behavior parents are trying to eliminate (the child becomes more aggressive).

2)Bandura’s 2nd experiment:1st phase; participants tested in 3 conditions (model rewarded, model punished and model neither rewarded nor ppunished).2nd phase; children were offerer rewards for imitating the model’s behaviour.

Long term effects and ethical issues were not considered in the experiment. 6-8 months later, children showed the same aggression (40% of them).

If you have been the victim of physical abuse as a child, you are very much likely to be an abusing parent than if you haven´t.

Bandura’s Results:1st phase; 1st group more aggressive than 2nd group (but no more than control group)2nd phase; under those conditions the 3 groups reproduced the same number of imitative aggressive acts.

The bobo doll is an inanimate object, a toy. Therefore the child sees the situation as play. It is not applicable to real life, how that the toy s purpose is to be hit.

When people believe they have control over their behavior and can achieve their goals they have “self-efficacy”.

It is a laboratory experiment, therefore it lacks of ecological validity. It doesn´t represent the child´s real and home life, it only shows the behavior in that certain condition.

Anxiety is experienced when we think of ourselves of being “ill-equipped” to manage potentially painful situations.

TRANSMISSION OF AGGRESSION THROUGH IMITATION OF AGGRESSIVE MODELSEVALUATION OF THE EXPERIMENT – 2PSY

Theoretical issues Subsequent research

Methodological issues

Applications and implications

Bandura: sees aggression as a social learning behaviour (aggression is a learned behaviour.

Learning is different than performance.

Not generalizable. Bandura´s experiment stimulated further studies on media violence.

Presence of models:- Facilitate aggressive behaviour- Shapes behaviour + attitude

There are two types of reinforcement:Direct and vicarious (indirect)

The long term effects aren´t defined but could depend on the previous characteristics of the participants.

This lead to the theory of the “cycle of violence”.

Reinforcement:- Direct; reinforced to imitate behaviour- Vicarious; behaviour (reinforcement or punished)

Behaviour + Reward:More imitation

Observational learning is still considerable in explaining the impact of media violence.

Factors leading to aggressivenes:-Being abused- witnessing violence.

People learn from actions, as well as from symbolic representations (images / verbal)

Learnes by classical conditioning: can lead to phobias.

There are three therapies for phobias, and the modelling one was the most effective.

http://www.youtube.com/watch?v=eqNaLerMNOE