Lecture 2

Question 1

What is temperament?

Answer 1

individual differences in emotion, activity level, and attention that are exhibited across context and present from infancy

Question 2

between-person approach

Answer 2

Thomas & Chess 1977

• easy
• difficult
• slow to warm up

Question 3

within-person approach

Answer 3

Rothbart et al, 2001

• fear
• distress
• attention span

Question 4

biological families and temperament

Answer 4

not possible to disentangle the effects of genetic (nature) and environmental (nurture) factors
there is twin designs and adoption design

Question 5

adoption design

Answer 5

biological families “genetic-plus-environmental” parents

shared genes -> biological parents
shared environment -> adoptive parents

genetic relatedness: birth parents and adopted child (50% mother, 50% father)
- adoptive parents and adoptive child (0%)

similarities in behaviour:

• adoptive parent and adopted child (environmental influences)
• birth parent and adopted child (genetic influences)

Question 6

limitations of adoption design

Answer 6

• adoptees are not placed randomly into adoptive families, they tend to be chosen to provide environments that are low risk
• may not be generalisable
• prenatal influences not taken into account
• adoption is an unusual event in itself

Question 7

twin design

Answer 7

dizygotic = 50% genes 
monozygotic = 100% genes 

compare resemblance of MZ and DZ twins to allow for a rough estimate of separate genetic and environmental contributions to a trait

assessed with correlation (r) between twins from each pair (separate from MZ and DZ)

MZ are seen to be more similar for temperament than DZ

Question 8

twin design limitations

Answer 8

• equal environment assumptions (MZ share more similar)
• not generalizable to wider population e.g. twins more susceptible to prenatal trauma
• MZ twins may not be 100% genetically identical

Question 9

heritability

Answer 9

• a statistical estimate for a population studied
• heritability estimate applies only to a particular population living in particular environment at particular time
• heritability estimate does not account for a complex interplay between genetic and environmental factors

Question 10

3 points to summarise

Answer 10

1. can estimate genetic (nature) and (nurture) influences on individual differences in a temperament trait in population
2. suggests traits are heritable, but environment does influence
3. role of genetic influence can change across development