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

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

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

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

Environmental Influence A trained brain

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

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

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.

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

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

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.

Culture and Self

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

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

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 email author. Evolutionary connection – human evolution based on social connectedness.

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

The Nature and Nurture of Gender Gender and Culture

The Nature and Nurture of Gender

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

The Nature and Nurture of Gender Two theories of gender typing