Task 5

Question 1

Heritability of Personality

Answer 1

.50-.65, little if any nonadditive (comparing MZ and HZ)

• Nearly always at least moderate factor even in attitudes

Question 2

Environmental factors influence personality

Answer 2

decrease to near zero after adolescence

Question 3

Behavioural genetic studies

Answer 3

studies of human twins and adoptees

Question 4

Comparing identical and fraternal twins raised together

Answer 4

o Alternative to raised apart studies

o Any extra similarities of identicals is supposed to be caused by genes, double the difference and you get the heredity

Question 5

Additive genetic influence

Answer 5

genes contributing separately to making ones level of trait a bit higher or lower
 effects of genes can be estimated by adding together their sperate effects

Question 6

Non-additive genetic effects

Answer 6

 Effect is only seen if the person has two alleles, the effects depend on the presence or absence of other allele (specific combinations of traits)

Question 7

How to detect non-additive effects

Answer 7

o when nonadditive genetic influences on a trait are important, identical twins will be considerably more than twice as similar as fraternal twins will be. If we see that identical twins are more than twice as similar as fraternal twins, this tells us that nonadditive genetic influences are involved

Question 8

Common environment influences

Answer 8

o	2(heritability MZ – heritability DZ) the difference to the heritability is the influence of the environment
o	Or just compare biological unrelated persons that live in the same environment

Question 9

Unique environmental influences

Answer 9

o Sampling siblings and determine which were treated differently by there parents an then compare it to same treated siblings, same with friend groups
o Or they just figure out how much variance in a trait is left over
o Caused by differences in parental treatment and different peer groups (only .15 correlation)

Question 10

Assimilation effect

Answer 10

the tendency to emphasise similarities between related persons

Question 11

Contrast effect

Answer 11

the tendency to emphasise differences between related persons (comparing to the other twin can falsify self-report)
 Use other-report of someone who only knows one twin or behaviour Reports

Question 12

Two assumptions for heritability of Personality

Answer 12

No assortative mating and no contrast/assimilation effect

Question 13

Womb environment

Answer 13

features of the womb environment can constitute aspects both of the common and the unique (for normal siblings) environment (not significant)

Question 14

Equal environment assumption

Answer 14

There is a influence of environment but it is rather small

Question 15

Molecular genetic studies

Answer 15

identified different alleles that account for differences in Neurotransmitter production and are so weakly correlated to some traits (serotonin=harm avoidance dopamine=novelty seeking)

Question 16

Genotype-environment interaction

Answer 16

the same environment will influence peoples levels of a given characteristic in different ways depending on their genetic characteristics (not very strong)

Question 17

Genotype-environment correlation

Answer 17

genetic tendencies might actually cause you to be exposed to some kinds of environments more than other kinds, and the differences between those environments might then influence the development of your personal characteristics (correlation can be positive or negative)

Question 18

Passive genotype-environment correlation

Answer 18

children inherit this combination of genes and environment passively, e.g. sporty parents pass on mindset and sporty genes, and not as result of their own behaviour

Question 19

Reactive genotype-environment correlation

Answer 19

other peoples reaction to the child’s genetic tendencies, e.g. supporting the child in sports, end up influencing the environment that he child experiences

Question 20

Active genotype-environment correlation

Answer 20

the child actively chooses environments, e.g. finds sport satisfying so it sticks to it, as a function of his or her genetic predisposition

Question 21

sex differences

Answer 21

o Genes that influence personality traits do not differ in the two sexes
o Sometimes there are sex differences in heritability

Question 22

Assortative mating

Answer 22

tendency for parents to be similar in their levels of the trait
o Is not actually happening

Question 23

Psychological interests

Answer 23

heritability is around .36 and environmental influence accounts for 10% for each trait

Question 24

Psychiatric illnesses

Answer 24

o Schizophrenia has heritability of about .80 mostly additive
o Major depression has heritability of .40
o Panic disorders, generalized anxiety disorder and phobias are moderately heritable, largely additive, few if any sex differences
o Alcoholism .50-.60 mostly because of additive genetic effects
o Antisocial behaviour: additive and in the range .41-.46, shared environment influences decrease from childhood to adulthood

Question 25

Social attitudes

Answer 25

o Conservation: only environmental influence on conservationism to age 19, heritability .65 for males .45 for females, some is nonadditive
o Religiousness: in 16 years olds .11 for girls .22 for boys and strongly influenced by shared environment .60 girls .45 boys.
 Heritability is moderately in adults with some environmental influences

Question 26

Difference-detecting adaptions

Answer 26

humans have evolved specialized adaptions for tracking and acting on these important induvial differences (e.g. attractiveness, intelligence, health etc.)

Question 27

Life-history theory

Answer 27

broad formulation of the major trade-offs in an individual’s life with respect to capturing and allocating energy (e.g. investing in growth, kin selection or parenting)
o Individuals choose by their own sometimes based on already existing feature where the allocate their energy

Question 28

Costly signalling theory

Answer 28

individuals compete with each other in sending signals to others about their qualities
o They are so costly that an individual has on focus on one which creates differences between individuals

Question 29

Balancing selection

Answer 29

when genetic variation is maintained by selection, such that different levels on a trait dimension are favoured, or are adaptive, in different environmental conditions to the same degree

Question 30

Environmental Heterogeneity in Fitness Optima: (Fluctuating optimum)

Answer 30

if selection pressures vary over time and space, then selection can favour different levels of a personality trait in these different environments
 7R allele, associated with novelty seeking and extraversion, occurs in dramatically different rates in different geographical regions

Question 31

Frequency-dependent selection

Answer 31

occurs when two or more strategies are maintained within a population at a particular frequency relative to each other

Question 32

Mutation load

Answer 32

o Individuals differ in their mutation load

o Heritability of some traits originates from individual differences in mutation

Question 33

Reactive heritability

Answer 33

refers to selection for species-typical psychological mechanisms that are flexibly responsive to changes in environmental conditions (e.g. becoming more risk averse after becoming father)