Nature v. NurtureGenetic,

biological make-upEnvironmental

experiences

Molecular genetics = studies the molecular structure and function of genes. Every cell nucleus in your body

contains the genetic master code for your entire body. Master code = 46

chromosomes (23 from each parent)

Genome – the complete instructions for making an organism, consisting of all the genetic material in that organism’s chromosomes Human Genome Project =

Completed in 2003; determined the complete sequence of the 3 billion DNA subunits (bases), identify all human genes, and make them accessible for further study

http://www.ornl.gov/sci/techresources/Human_Genome/posters/chromosome/

Bradley is

98% 99.9%

99.9%

Sam Allen

The four nucleotide letters – ATCG – is virtually the same in all humans. So, why are we so complex?????

Behavior Genetics – perspective of psychology that studies the influence of nature (genes, biology, heredity) and nurture (environment, experiences) on behavior Epigenetics – study of turning genes on and off.

Nurture can alter the switches (called promoters) that control gene expression (activation/inactivation). Explains why one identical twin gets a

disease/disorder and the other does not (have same genome but different epigenome).

Genetic flexibility – some genetic make-ups are more or less sensitive to environment and thus some kids are more moldable than others. (http://www.thisamericanlife.org/radio-archives/episode/360/switched-at-birth)

Homosexuality – boys with older brother more likely to be homosexual. Immune response affects the expression of key genes during brain development in a way that affects sexual orientation

Language – impossible to learn human language by trial and error alone; human beings must come already equipped with an innate grammatical skills. The capacity to learn is written into the human brain by genes that open and close a critical window during which learning takes place. If a child is not exposed to a lot of spoken language during the critical learning period, he or she will always struggle with speech.

Love – The promoter upstream of the oxytocin and vasopressin receptor genes. The insertion of an extra chunk of DNA text, usually about 460 letters long, into the promoter makes the animal more likely to bond with its mate. The extra text does not create love, but creates the possibility of falling in love after the right experience.

Antisocial Behavior – those with high active monoamine oxidase A genes were virtually immune to the effects of mistreatment. Those with low active genes were much more antisocial if maltreated, yet – if anything – slightly less antisocial if not maltreated. The low active, mistreated men were responsible for four times their share of rapes, robberies and assaults. Maltreatment is not enough; you must also have the low active gene. And it is not enough to have the low active gene, you must also be maltreated.

Many people are worried about a Brave New World in which parents or governments will try to re-engineer human nature. Others see genes as a threat to free will and personal responsibility, but… “genes cannot pull the strings of behavior directly.” Behavior is caused by the activity of the brain, and the most

genes can do is affect its wiring, size, shape and sensitivity to hormones and other molecules.

Genes must exert their effects by acting together in complex combinations. No single gene for musical talent that ambitious parents can have implanted into their unborn children. It might take hundreds or thousands of the right genes, with a different combination needed for each child.

Culture, germs, accidents, chance encounters in life and random events in the development of the brain in utero affect expression of genes

According to the article “Are your Genes to Blame?”, personality, intelligence, and susceptibility to psychological maladies such as schizophrenia, OCD, and major depression are partly heritable (actually all behavioral traits are partly heritable). But what does that exactly mean

Heritability = the proportion of variation among individuals that we can attribute to genes. (Explained differences between people!!)

EX: Heritability of IQ = 70% we can attribute 70% of the differences in IQ among individuals, such as members in this class, to genes. This does not mean that for an individual 70% of the trait comes from genetics and 30% from environment.

Neuroticism - Emotional Instability

A tendency to experience unpleasant emotions easily, such as anger, anxiety, depression, or vulnerability

Extraversion Energy, positive emotions, the tendency to seek stimulation and the company of others

Openness to Experience

Appreciation for art, emotion, adventure, unusual ideas, imagination, and curiosity

Agreeableness A tendency to be compassionate and cooperative rather than suspicious and antagonistic towards others

Conscientiousness Control of impulse, a tendency to show self-discipline, act dutifully, and aim for achievement; planned rather than spontaneous behavior.

Temperament = response style to environment; emotional reactivity and intensity.

Goodness of Fit = how well a child’s temperament fits with his/her environment. • An effective match between child-rearing practices and child’s

temperament leads to favorable development and psychological adjustment.

Evolutionary psychology is the science that seeks to explain why humans act the way they do.Seeks to reconstruct problems that our ancestors faced in their primitive environments, and the problem-solving mechanisms they created to meet those particular challenges. The science then attempts to establish the common roots of our ancestral behavior, and how those common behavioral roots are manifested today in the widely scattered cultures of the planet. The goal is to understand human behavior that is universally aimed at the passing of one's genes into the next generation. Look at our behaviors: Can you answer these questions using evolutionary psychology?Why do infants fear strangers when they become mobile?Why are most parents devoted to their children?Why do we divide people into categories?Why do we have more phobias about spiders and snakes than electricity and nuclear weapons?

Men want:HealthyYoungWaist 1/3

narrower than hips.

Women want:WealthPowerSecurity

Sperm is Cheap…. Eggs are not!

Males Females

Chromosomes XY XX

Primary Sex Characteristics

Testes Ovaries

Hormones Androgen Estrogen

Secondary Sex Characteristics

Deep voice; facial hair; increased muscles mass

Breast development; widening of hips

Sex: biological term referring to ascribed genetic, anatomical, and hormonal differences

• Gender: term referring to social and psychological traits (i.e., strong, caring, independent, leader)

• Gender Roles: commonly assigned tasks or expected behaviors of individuals because of their sex category (i.e., take care of kids, play football, show emotions)• Demo: Children’s Book – As I read the story, write down the

social and psychological traits you hear for males and females! Based on these social/psychological traits, what behaviors can a male or female participate in?

• Formation of Gender Identity: ability to correctly label own gender, and to identify others as boys/men and girls/women

• Around 2 years of age -Complexity through Brain Development and Age *(See Next Slide for Developmental

Milestones)• Gender Stability/Constancy: the understanding

that you stay the same gender through out life

At 9 months, most babies can discriminate male and female faces

Ages 2 to 3, start to label themselves as boys or girls (but don’t think of gender as permanent), begin to prefer same-sex playmates and sex-typed toys. Children typically begin to assign occupations, toys and activities to the stereotypical gender.

By age 5, associate personality traits with males and females.

By age 6, gender divide in friendships is marked. By age 8/9 years this stereotypical knowledge is well

developed. Primary school children pay more attention to the

behavior of same sex adults & kids, and play more with new toys that are labeled as appropriate for their own gender.

Summary, children from 1-2 yrs are aware of and affected by gender, and this becomes a steadily more potent force in behavior and attitudes especially from age 6 onwards.

GENDER GENDER ROLES GENDER GENDER ROLES

Males Males Females Females

Independent; assertive

Provide for their families; compete with others

Passive; cooperative

Share; do not complain or stand up for themselves

Aggressive; tough

Hide emotions and fears; stand up for themselves

Nurturing; warm

Raise children; take care of household; express emotion; show affection

Risk-takers; athletic

Men should protect their families and “hunt” for food; participate in “rough and tumble” play or sports

Cautious; delicate

Play with dolls; participate in dance

Mechanical Like to work with tools and objects; prefer dealing with things; repair things, such as the home, cars, etc; pursue science and mechanical careers/subjects

Social Help others; pursue careers/subjects in the fields of humanities, education, nursing

Social Learning Theory: Bandura and Mischel emphasize the role of 1) direct reinforcement 2) modeling in shaping children’s behavior & attitudes

Boy throws ball, other boys join in Boy plays with doll, other boys make fun of him Boy will throw ball more and play with dolls less

Gender Schema Theory - Child establishes a primitive gender schema, and begins assimilating new experiences into this schema.

• Identify own gender• Learn gender schema (internal cognitive framework on how

boys or girls are supposed to behave) How and what we are taught-See Surveys!

• Evaluate behavior based on whether it meets or does not meet gender schema, and adjust behavior accordingly. • EX: Girl who refuses to wear pants in Winter because schema

tells her boys wear pants and girls wear dresses, even when parents are encouraging and rewarding her to do so.

Age 2 or 3 years. Requires lots of cognitive ability!!! As cognitive complexity develops, gender schema takes over.

From the moment of birth, on the basis of external biological characteristics, males and females are treated differently (characteristics and behaviors that fit the society’s image of the ideal male or female)…

Way parents DESCRIBE AND TREAT their children Newborn daughters are often described as soft, delicate, fine featured,

little, beautiful, and pretty. “ Look at those cute little dimples!” They depict their sons as strong, firm, alert, and well coordinated. “Look at his husky little biceps!”

Parents talk more to their young daughters, give them less autonomy and encourage them to help others, while encouraging boys to express certain types of emotions but not others, like fearfulness. Many boys are encouraged to be more independent and exploratory while girls are protected from situations that might prove harmful.

When people know they are holding baby girls, they are gentle, they cuddle and kiss baby girls while calling her sweet and dainty. When parents are holding boys, they are more likely to bounce them or roughhouse with the child. Clothing - dress babies in pink or blue, dresses or pants.

NAMES parents select. Boys are more often given strong, hard names that end in consonants, Bill Tom

Peter John. Girls are more likely to be given soft pretty names with vowel endings such as

Linda, Christina, Susie. TOYS given to boys or girls.

Boys’ rooms are filled with sports equipment, army toys, building and technical toys, and cars and trucks.

Girls’ rooms have fewer toys, and most are related to dolls and domestic roles. BOOKS and CARTOONS

In a classic study of more than 3,000,000 award winning children’s books in the US, they found: males appear more often in stories, sometimes as male animal characters activities of male and female characters in books differ, with boys playing

active roles and girls being passive or simply helping males adult women are pictured as more passive and dependent, and few women

are depicted as working outside the home Males are depicted carrying out a range of activities and jobs.

Katie and Sam (Mrs. Allen’s Children)

Broca's area and Wernicke's area are connected by a bundle of nerve fibers called the arcuate fasciculus. Linkage between Broca’s and Wernicke’s is tighter in

men more direct communication.

In women’s brains, corpus callosum are larger in women better communication between

hemispheres. Bilaterlization allows women to excel at verbal skills because more cross communication. Use

hemispheres more equally.

In women’s brains, almost every area of left and right cortex is active during language. Kimura’s Area – extra chip that helps

Broca’s and Wernicke’s area communicate with right hemisphere. Also, Wernicke’s area engages with mirror area in

right temporal lobe that is involved with emotional comprehension richer, more emotional langauage

Kimura’s Area