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Bobo doll experiment. Context and implications. BehaviourismTheoryMethod. Aggression-Instinct theories (Freud, Lorenz)-Frustration-aggression hypothesis (Dollard et al.). TV and violence:-Williams (1986)-Huessmann
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1. The Bobo Doll experiments: Bandura’s social modelling approach to aggression
3. Theoretical background: behaviourism
The behaviourist approach to experimentation
Main theorists: Pavlov, Watson, Skinner, Bandura
The Bobo Doll experiment
Evaluation
Implications of the Bobo Doll experiment
Research on the impact of TV: tackling confounding variables Outline:
4. Watson, J.B. (1913) – Psychology as the behaviorist views it
(Behaviourist Manifesto)
[Psychology] failed signally, I believe, during the fifty-odd years of its existence as an experimental discipline to make its place in the world as an undisputed natural science.[...]
The time seems to have come when psychology must discard all reference to consciousness; when it need no longer delude itself into thinking that it is making mental states the object of observation.[…]
I believe we can write a [new] psychology […]and never go back upon our definition: never use the terms consciousness, mental states, mind, content, introspectively verifiable, imagery, and the like. […]
It can be done in terms of stimulus and response, in terms of habit formation, habit integrations and the like. […]
What we need to do is to start work upon psychology, making behavior, not consciousness, the objective point of our attack. Behaviourism: a response to Freud
5. Focus on the observable (behaviour)
All that cannot be observed is ignored
Nearly all behaviour is learned
Focus on experimentation rather than speculation
Commitment to discovery, not dogma
Parsimony
Environmental determinism: tabula rasa, little importance attached to genes
Animal research can be generalized to humans
Behaviourist assumptions
6. Pavlov: Classical conditioning
Unconditioned Stimulus (food) > unconditioned response (dog salivates)
Conditioning: US paired with CS (bell) > UR (salivation)
CS (bell) > CR (salivation)
Skinner: Operant conditioning
Behaviour is not always learned on the basis of an unconditioned stimulus
Behaviour is determined by past history of reinforcement
Stimulus > Response
Shaping / Chaining
Nothing that is learned can’t be unlearned – implication for therapy
Bandura: Social modelling
Evolution of behaviourism
7. S-O-R
Acquisition ? performance
Behaviour can be learned in absence of reinforcement, by means of imitating others
Social Modelling can account for learning complex behaviours such as language Albert Bandura: Social Modelling approach
8. Sample / Subjects / Participants
36 boys and 36 girls, from Stanford Nursery, mean age 4 years 4 months
Independent Variable
Exposure to aggressive model or non-aggressive model
Dependent variable
Imitation / behaviour after the exposure (clearly operationalised)
Imitation of physical aggression: […] 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.
Imitative verbal aggression: Subject repeats the phrases, "Sock him," "Hit him down," "Kick him," "Throw him in the air," or "Pow"
Imitative nonaggressive verbal responses: Subject repeats, "He keeps coming back for more," or "He sure is a tough fella."
Mallet aggression: Subject strikes objects other than the Bobo doll aggressively with the mallet.
Sits on Bobo doll: Subject lays the Bobo doll on its side and sits on it, but does not aggress toward it.
…
Control group Design of the Bobo doll experiment
9. Design of the Bobo doll experiment
10. Design of the Bobo doll experiment
11. Inter-rater reliability
„In order to provide an estimate of interscorer agreement, the performance of half the subjects were also scored independently by second observer. „
Rater blind to the condition
„The male model scored the experimental sessions for all 72 children. Except for the cases in which he, served as the model, he did hot have knowledge of the subjects' group assignments.”
Matched-pairs design
„subjects in the experimental and control groups were matched individually on the basis of ratings of their aggressive behavior in social interactions in the nursery school.”
Pretest
During the pretest, a number of the subjects imitated the essential components of the model's behavior but did not perform the complete act, or they directed the imitative aggressive response to some object other than the Bobo doll. Two responses of this type were therefore scored and were interpreted as partially imitative behavior.
Design of the Bobo doll experiment
12. H1.„Subjects exposed to aggressive models would reproduce aggressive acts resembling those of their models and would differ in this respect both from subjects who served nonaggressive models and from those who had no prior exposure to any models.”
H2. „It was further predicted that observation of subdued nonaggressive models would have generalized inhibiting effect on the subjects' subsequent behavior, and this effect would be reflected in a difference between the nonaggressive and the control groups, with subjects in the latter group displaying significantly more aggression.”
H3. „One would expect, on this basis, subjects to imitate the behavior of a same-sex model to a greater degree than a model of the opposite sex.”
H4. „Since aggression, however, is a highly masculine-typed behavior, boys should be more predisposed than girls toward imitating aggression, the difference being most marked for subjects exposed to the male aggressive model.”
Hypotheses
13. „Scores of children in the aggressive condition were significantly higher than those of either the non-aggressive or control groups.”
Significance level
H1: supported or rejected? Results
15. Aggression is a learned behaviour, not an in-built instinct
Learning can take place in absence of any reinforcement, only via observation and modelling
Modelling is a powerful and fast way of learning
Implications for parents, teachers, psychotherapists (treatment of phobias) Conclusions
16. Bandura, Ross & Ross (1963): children watched films with either an aggressive or non-aggressive model
Filmed model produced even more aggression than live model
Model rewarded or punished for aggression
Children imitated the rewarded aggresive model the most
Bandura’s research as the ‘first generation’ of scientific research on the effects of media violence on children
Bandura’s further research
17.
January 15, 2007
Saddam Video Is Blamed for Deaths of More Children, by Tom Zeller Jr
According to the American Psychological Association, there’s no question that a daily diet of violent media becomes part of the psycho-social mix in an individual. This is based largely on the work of psychologist Albert Bandura, who highlighted the important role social modeling and observational learning plays in human motivation — and action. (Before that, psychologists had largely focused on a sort of Pavlovian model of learning, based on actions and consequences.) […]
Dr. Bandura’s classic „Bodo Doll Experiment” , in which children who were shown film of an adult aggressively beating an inflatable doll were more likely to imitate and repeat that behavior when exposed to a Bobo Doll themselves, is often cited in describing the power of violence in the media. […]
Of course, the science isn’t exactly settled on all this. An essay at the Museum of Broadcast Communications, while acknowledging the groundbreaking work of Dr. Bandura, and the complex relationship between mind and media, suggests “even among researchers who are convinced of a causal link between television and violence, explanations of when and why this occurs are varied.”
Implications of Bandura’s research
18. What do the Bobo doll studies really tell us about the effects of TV on children?
Films used in the study differ markedly from real movies (no plot, no causal justification for the model’s behaviour, which is quite bizzare)
Participants in an experiment know they are expected to play a particular role „Look, Mummy, this is the doll we have to hit” (Nobel, 1975)
Does not test long-term effects
Aggresion towards an inanimate toy only, not a living being
What else can you do with the Bobo doll?
Children in the experiment are not punished for their behaviour
Problems with ecological validity and hence generalization
Led to phase 2 research on the effects of media violence
Implications of Bandura’s research
19. There has been a tremendous amount of research on the effects of media violence on children and adolescents over the past 40 years.
Yet theorists still do not agree on this. Why?
September 17, 2000
Hollow Claims about Fantasy Violence by Richard Rhodes
[I]s there really a link between entertainment and violent behavior?
The American Medical Association, the American Psychological Association, the American Academy of Pediatrics and the National Institute of Mental Health all say yes. They base their claims on social science research that has been sharply criticized and disputed within the social science profession, especially outside the United States. In fact, no direct, causal link between exposure to mock violence in the media and subsequent violent behavior has ever been demonstrated, and the few claims of modest correlation have been contradicted by other findings, sometimes in the same studies. […] Research on effects of media exposure on children
20. Brainstorming: What effects would you like to test?
Formulate hypothesis
How would you test this hypothesis?
Who would be your participants?
How would you define your independent variable?
How would you define and measure your dependent variable?
How would you test long-term effects?
Would it be a laboratory experiment or a field (real –life) study?
How would you establish a causal relationship? Research on effects of media exposure on children
21.
Correlational studies do not establish causation
The importance of other variables difficult to assess
Weaknesses of laboratory experiments
Difficulties with field experiments
Difficulties with defining and measuring aggression reliably
Studies use different measures, difficult to compare
Little known about the mechanism
Even if media violence can cause aggression, how do you reduce the violence? Research on effects of media exposure: problems
22. Key reading:
Bandura, Ross & Ross (1961). Transmission of aggression through imitation of aggressive models. Journal of Abnormal and Social Psychology, 63, 575-582
To view vide footage from the experiment, go to: http://www.youtube.com/watch?v=pDtBz_1dkuk
Readings
23.
Additional reading:
Watson, J.B. (1913). Psychology as the behaviorist views it. Psychological Review, 20, 158-177. Available at: http://psychclassics.yorku.ca/Watson/views.htm
Murray, J.P. (1994). Impact of televised Violence. Hofstra Law Review, 22(4), 809-825. Available at: http://www.johnmurray.org/murray_a.htm
Anderson, et al. (2003). The influence of media violence on youth. Psychological Science in the Public Interest, 4(3), 81-110.
Freedman, J.L. (2001) Evaluating the Research on Violent Video Games. Paper devlivered at Playing By the Rules: The cultural policy challenges of video games. University of Chicago. (Available online at: http://culturalpolicy.uchicago.edu/conf2001/papers/freedman.html
Zeller, T. Jr (September 15 2007). Saddam’s Video is Blamed for Deaths of More Children. New York Times. Available at: http://thelede.blogs.nytimes.com/2007/01/15/saddam-video-is-blamed-for-deaths-of-more-children/
Rhodes, R. (September 17, 2000). Hollow claims about fantasy fiolence. New York Times, Section 4, p 19. Available at: http://query.nytimes.com/gst/fullpage.html?res=9F02EFD81138F934A2575AC0A9669C8B63&n=Top/Reference/Times%20Topics/Organizations/A/American%20Academy%20of%20Pediatrics
Readings