Biological underpinnings of personality

Question 1

twin studies: nature vs nurture

Answer 1

these studies examine identical twins raised apart and together to determine how genetics vs environment influence differences in personality

Question 2

twin studies findings

Answer 2

50% of the variance in personality is genetic, other 50 is non shared environmental factors

47% variance for neuroticism

61-63% variance for openness to experience

shared environment has very little effect on personality (57% chance identical twin will also be neurtoic if their twin is, while only 50% with strangers)

Question 3

jim twins

Answer 3

identical twins raised apart

adopted in 1940

both enjoyed math and disliked spelling

both drove chevys and smoked heavily

both married a woman named Linda

Question 4

why can siblings be so different

Answer 4

shared enviro factors may not have much impact on siblinsg bc of…

1) contrast effect: siblings want to differentiate themselves from each other, want to be their own person (ex. girls w brothers report more feminine occupational interests)

2. birth order: youngest siblings may get less attention when younger but more when older…. middle children may never get to be the centre of attention, so they may be more attention seeking

Question 5

limitations of twin studies

Answer 5

1. restriction of range: twins often get adopted into similar homes (stable, middle class, married families)… no cpnsideration of cultural inlfuence (twins observed come from same culture and same generation)
2. lack of specififc info on the influence of nonshared environmental factors (friends,teachers, media exposure, birth order)
3. identical twins look very much alike and share the same prenatal environment

Question 6

gene-environment interaction

Answer 6

genes and environmental factors work together to influence personality

predispositions can be triggered or not

Question 7

epigentics

Answer 7

study of how environmental triggers cause differences in gene expression

gene expression depends on how the genes are transcribed by cells, and whether or not they are activated or not

Question 8

biology and the big 5

introversion

agreeableness

neuroticism

extraversion

low conscientiousness

openness to experience

Answer 8

introversion: more sensitive to stimuli

high agreeableness: more activity in frontal lobe (emotional intelligence)

high neuroticism: more activity in the amygdala

extraversion: higher brain activity in amygdala

low conscientiousness: higher dopamine levels, more activity in the ventral striation

high openness to experience: better ST memory

Question 9

double standard for promiscuity

Answer 9

male opportunism and female selectiveness

Question 10

double standard for parental investment

Answer 10

women tend to express more nurturance

Question 11

women’s fertility and personality

Answer 11

on high fertility days:
- body scent more preferred by men
- more tips fpr lap dances (335 vs 260)
- prefer stereotypically masculine men
- wear more provacative clothing
- voices are higher pitched

Question 12

testosterone rises when:

Answer 12

-men expect competition, then again when they win

-they gain status in a social group

-when their sports team/ political candidate wins

Question 13

link between aggression and testosterone

Answer 13

positive but weak correlation

violent criminals have higher levels than non violent ones

Question 14

testosterone and sexual relationships

Answer 14

single men and women tend to have higher levels

Question 15

2d:4d ratio women

Answer 15

low: assertive, seek leadership, sensation seeking, risk taking

Question 16

2d:4d ratio men

Answer 16

low: take risks, invest money in stocks, expressing an unpopular opinion

Question 17

2d:4d ratio men and women

Answer 17

low ratio: low on neuroticism and agreeableness, have better mathematical, musical, and athletic ability