Contemporary Study: Brendgen Et Al Flashcards
What was the aim of the contemporary study?
To see the contribution that genes and the environment have on aggression
What was the sample of the contemporary study?
234 of mono and dizygotic pairs, 44 males (monozygotic), 50 female (monozygotic), 41 males (dizygotic), 32 female (dizygotic)
What was the procedure of the contemporary study?
Teachers rated aggression on a liket scale from 1-3 based on examples of aggression they were given on a questionnaire.
Peers then had to pick out the 3 most aggressive children from photographs which matched statements they were told
The physical and social aggression scores were then added together to produce two overall scores.
Two comparisons were then conducted:
1- comparing teacher and peer ratings to check for consistency
2- comparing the concordance of forms of aggression between identical and non- identical twins
What were the weaknesses of the procedure used?
Measurements are objective (based on opinion)
Relationship between child and student may differ
Bias
What was the average percentage of physical aggression?
58.5%
What was the average percentage of social aggression?
57%
What did the study find about what impacts physical aggression the most?
Genetics
What did the study find about what impacts social aggression the most?
A non-shared environment
Explain the results of the contemporary study you have learned in biological psychology (4 marks)
Brendgen found on average 58.5% of physical aggression can be explained by genetics, this was suggested through teacher and peer ratings of aggression which were highly concordant for identical twins compared to non-identical twins. This means that aggression is largely caused by genetics.
Brendgen also found that on average 57% of social aggression can be explained by a non-shared environment, this was suggested through teacher and peer ratings of aggression which had a higher variance for mixed and non identical twins.
What were the conclusions drawn from the contemporary study?
Physical aggression is largely contributed to by genetics as concordance was higher in monozygotic twins
Social aggression is largely contributed to by the environment
Evaluate Brendgen’s contemporary study (8 marks)
Generalisability- Strength
Results are representative due to the sample made up of 234 pairs of twins of which consisted of identical sex twins, non- identical same sex twins and mixed sex non-identical twins
Reliability- Strength
Results have inter rater reliability as teachers and peers rates both physical and social aggression. Multiple teachers rates each child to create an overall aggression score.
Results were compared for consistency between ratings
Application- Strength
Results are useful in society as they suggested that physical aggression is contributed to by generics while social aggression is linked more with the environment. Therefore, this can be used to identify individuals that are more likely to physically aggressive due to a defective gene like MAOA, as well as finding ways to lower social aggression by changing factors within the environment such as education or social groups.
Validity- Weakness
Results lack internal validity because physical and social aggression scores were based on ratings given by teachers and peers. Therefore, this increases the risk of bias as well as interpretation of identifying different forms of aggression.
Ethical- Strength/ Weakness
Ethical implications
Aggression is not being encouraged only measured,
Not causing harm however the investigation is socially sensitive as it encourages judgement and fixed views.
Also, increases the responsibility onto parents
Explain one strength and one weakness of the contemporary study you have studied in biological psychology (4 marks)
Brendgen et al contemporary study is praised for its level of application within society. This is because results have suggested that physical aggression is contributed to by genetics while social aggression is largely affected by the environment. Therefore, this can be used to identify individuals who are more likely to be physically aggressive due to a defective gene like MAOA, as well as helping to reduce social aggression within society by altering the environment such as changing the way people learn or social groups. However, Brendgen et al contemporary study can also be critiqued for its lack of internal validity, this is because results were based on ratings given by teachers and peer to create an overall score, however these were heavily based on interpretation of aggressive behaviour. Therefore, it can be argued results were biased and invalid.
Evaluate one twin study you have studied in biological psychology (8 marks)
One twin study was conducted by Brendgen et al, Brendgen aimed to investigate how environmental factors can interact with genes to influence social and physical aggression.
Strength- inter rater reliability
This is because teachers and peers rated both types of aggression and multiple teachers rated each child to create an aggression score.
This is because results were compared for consistency between ratings reducing extraneous variables such as bias.
Weakness- lack of internal validity
Physical and social aggression scores were created on the basis of ratings
Therefore, different individuals may misinterpret the use of scales making results invalid.
