Brendgen et al (twin studies)

Question 1

what is the aim of the study

Answer 1

to see if aggression is caused by genes or the environment

Question 2

give 5 examples of the sample

Answer 2

recruited from Quebec Newborn twin study

born between Nov 1995- July 1998

234 twins

123 pairs were DNA tested

MZ female twins- 50
DZ female twins- 32

Question 3

what languages were spoken

Answer 3

french and english

Question 4

how long was the data gathered for

Answer 4

5, 18, 30, 48 and 60 months

Question 5

what measurement did teachers use for the ratings

Answer 5

series of statements taken from preschool social behaviour scale

used a 3 point scale

asked a series of questions such as ‘do they get into fights’

Question 6

what measurement did peer ratings use

Answer 6

circle 3 pictures of children they thought would have imitated 4 different behaviour descriptions

Question 7

give 2 examples of results

Answer 7

63% of shared genetics had aggression

50-60% of physical aggression can be linked to genetics