1. 1st Environmental Influence - Prenatal
One arrangement – two separate placentas
One may have a better placement
Separate placentas can make babies dissimilar in traits such as social competence and self-control

2. 1st Environmental Influence - Prenatal
Second arrangement – twins share a placenta

3. Environmental Influence
Experience affects brain development
Impoverished
environment
Rat brain
cell
Enriched
Implications for humans?

4. Benefits of “Handling”
Touching and holding results in faster weight gain and neurological development for both babies and animals
Experience produces a bundle of neural connections
Language development is easy really early, almost impossible after adolescence

5. Environmental Influence
A trained brain

6. Environmental Influence - Parenting
Blame on parents is often overstated
Hindsight example in separated twin study – “Why are you so cleanly?”
Parents DO matter – evidence is in the extremes
Parenting amounts to less than 10% of personality differences

7. Environmental Influence - Peers
Peer influence is STRONG
Preschoolers will eat food around other kids that they will otherwise refuse to eat at home
Children will adapt accents of peers of accents of their parents
Teens who start smoking typically do so BECAUSE they have friends who model smoking… parental influence is not as important

8. Peer vs. Parent Influence
Parents more strongly influence:
Education
Discipline
Responsibility
Orderliness
Charitableness
Ways of interacting with authority figures
Peers more strongly influence:
Learning cooperation
Finding popularity
Inventing styles of peer interaction
Young people find peers more interesting, but look to parents when contemplating their own futures.

9. Environmental Influence
Culture
the behaviors, ideas, attitudes, and traditions shared by a group of people and transmitted through generations
Norm
an understood rule for accepted and expected behavior

10. Environmental Influence
Personal Space
the buffer zone we like to maintain around our bodies
Memes
self-replicating ideas, fashions, and innovations passed from person to person

11. Culture and Self
Individualism – giving priority to one’s own goals over group goals and defining one’s identity in terms of personal attributes.
Collectivism – giving priority to goals of one’s group (extended family, work group, etc) and defining one’s identity accordingly.

12. Culture and Self

13. The Nature and Nurture of Gender
X Chromosome
the sex chromosome found in both men and women
females have two; males have one
an X chromosome from each parent produces a female child
Y Chromosome
the sex chromosome found only in men
when paired with an X chromosome from the mother, it produces a male child

14. The Nature and Nurture of Gender
Testosterone
the most important of the male sex hormones
both males and females have it
additional testosterone in males stimulates:
growth of male sex organs in the fetus
development of male sex characteristics during puberty
Role
a set of expectations (norms) about a social position
defining how those in the position ought to behave

15. Gender and Social Connection
Females are more interdependent than males.
Teen girls – more time with friends.
Late adolscents – more time social networking
Adults – prefer face-to-face conversation, use conversation to explore relationships
Males prefer conversation to communicate solutions
Stark enough difference to predict gender of author.
Evolutionary connection – human evolution based on social connectedness.

16. The Nature and Nurture of Gender
Gender Role
a set of expected behaviors for males and females
Gender Identity
one’s sense of being male or female
Gender-typing
the acquisition of a traditional masculine or feminine role

17. The Nature and Nurture of Gender
Gender and Culture

18. The Nature and Nurture of Gender

19. The Nature and Nurture of Gender
Social Learning Theory
theory that we learn social behavior by observing and imitating and by being rewarded or punished
Gender Schema Theory
theory that children learn from their cultures a concept of what it means to be male and female and that they adjust their behavior accordingly

20. The Nature and Nurture of Gender
Two theories of gender typing