What’s it all about? Nature = Behaviours, motivation, emotions, etc, that are essentially biological and that we were born with (inherited). Nurture = Behaviours, etc, that are essentially learnt and therefore were not born with. (This learning is known as early socialisation.)

Imprinting Baby ducks will follow the first thing see after they are born Thinking it is their mother.

DNA Most human beings have 23 pairs of chromosomes so 46 in total. 23 rd chromosome determines sex Chromosome contain our DNA which determines all of our characteristics.

What does DNA determine about us? To a degree: Everything. Down Syndrome babies have 47 chromosomes. An extra 21 st chromosome Most individuals who have Down syndrome have intelligence quotient (IQ) scores in the mild to moderate range of retardation. Children with Down syndrome need to be in special educational programs that give them a good environment for learning and that keep pace with their intellectual capabilities.

Nature vs. Nurture in IQ Are differences between people due to environmental or genetic differences? Misunderstanding the question – “Is a person’s intelligence due more to genes or to environment?” – no genes = no intelligence – both genes & intelligence crucial for any trait

Study Techniques Twin Research – Identical versus fraternal twins (monozygotic versus dizygotic) – Shared environmental experiences Common experiences, e.g. parent’s personality, intelligence, SES status, neighborhood live in, parenting techniques – Nonshared environmental experiences Child’s own experiences within and outside the family that are not shared with siblings

Twins

Genetic Influences The most genetically similar people have the most similar scores Similarity of intelligence scores (correlation) Identical twins reared together Identical twins reared apart Fraternal twins reared together Siblings reared together Unrelated individuals reared together

Family Influence on IQ Transient influence of family in which you are raised – adoptive siblings as children and adults – identical vs. fraternal twins reared together Fraternal twins Identical twins

IQ Differences among Racial/Cultural Groups Find differences among racial & cultural groups on IQ – American Blacks score about 15 points lower than Whites WHY? – genetics? Witty & Jenkins (1935) No support for genetic differences – environment?

The study of Feral Children Wild children who have been separated from society. The Case of Genie. Other cases.

Temperament & Personality Temperament: a set of tendencies to respond in predictable ways. Buss & Plomin (1984) found.50 to.60 average correlations between temperament scores of identical twins. The correlations for fraternal twins are about 0.

Raised apart, yet both grow up the same

Psychological Disorders Schizophrenia: disturbances in logical thinking, emotional expression, social behavior. Originally: thought due to a cold and inconsistent mother. Now: concordance rates for identical twins: 48%; fraternal twins 17%. 1% of the general population has Schizophrenia.

Sensorimotor stage (Infancy). In this period (which has 6 stages), intelligence is demonstrated through motor activity without the use of symbols. Knowledge of the world is limited (but developing) because its based on physical interactions / experiences. Children acquire object permanence at about 7 months of age (memory). Physical development (mobility) allows the child to begin developing new intellectual abilities. Some symbollic (language) abilities are developed at the end of this stage. Pre-operational stage (Toddler and Early Childhood). In this period (which has two substages), intelligence is demonstrated through the use of symbols, language use matures, and memory and imagination are developed, but thinking is done in a nonlogical, nonreversable manner. Egocentric thinking predominates Concrete operational stage (Elementary and early adolescence). In this stage (characterized by 7 types of conservation: number, length, liquid, mass, weight, area, volume), intelligence is demonstarted through logical and systematic manipulation of symbols related to concrete objects. Operational thinking develops (mental actions that are reversible). Egocentric thought diminishes. Formal operational stage (Adolescence and adulthood). In this stage, intelligence is demonstrated through the logical use of symbols related to abstract concepts. Early in the period there is a return to egocentric thought. Only 35% of high school graduates in industrialized countries obtain formal operations; many people do not think formally during adulthood. Stages of Cognitive Development