Heritability, Twin Studies, and Gene-Environment Interactions in Psychology

What is the nature vs nurture debate?

The debate about the relative contributions of genetics (nature) and environment (nurture) to human development.

What is heritability?

An estimate of the degree of variation in a phenotypic trait in a population that is due to genetic variation between individuals.

What does a heritability estimate range from?

0 to 1.00, where high values indicate strong heritability and low values indicate weak heritability.

What is the first law of behavioral genetics?

All human behavioral traits are heritable.

What is the significance of the phrase 'at least in part' in heritability?

It indicates that genetic differences among individuals contribute to variations in traits.

What is the difference between monozygotic and dizygotic twins?

Monozygotic twins are identical twins sharing 100% of their genes, while dizygotic twins are fraternal twins sharing about 50% of their genes.

What is the Minnesota Twin Study?

A study that investigated the development of twins raised in different environments compared to those raised together.

What are some traits that show significant genetic influence?

All psychological traits, including ability, personality, and interests.

What is the HOME tool used for?

Measuring the quality of children's home lives and predicting language development, literacy, and IQ.

What are the risks associated with poverty?

Lifelong poor physical health, cognitive development deficits, mental illness, and antisocial behavior.

What are the risks associated with affluence?

Poor academic achievement, substance abuse, delinquency, and anxiety.

What is authoritative parenting?

A parenting style characterized by high warmth and high demands.

What is inductive discipline?

A discipline strategy that directs attention to the effects of actions on others.

What is the correlation between inductive discipline and child outcomes?

Inductive discipline is positively correlated with child empathy and prosocial behavior.

What is the correlation between power assertion and child outcomes?

Power assertion is negatively correlated with child empathy and prosocial behavior.

What is a passive gene-environment correlation?

When genetically influenced traits in parents affect the environment for their children.

What is an evocative gene-environment correlation?

When genetically influenced traits affect other people's reactions to the child.

What is an active gene-environment correlation?

When individuals select environments based on genetically influenced traits.

What does gene-environment interaction refer to?

The effects of environmental factors on development that depend on individuals' genetic makeup.

What is the significance of the statement 'no traits are 100% heritable'?

It emphasizes that environmental factors also play a role in the expression of traits.

What does socioeconomic status (SES) encompass?

Years of education, job prestige, and income.

What are WEIRD societies?

Western, Educated, Industrialized, Rich, and Democratic societies often used to generalize research findings.

What is the impact of secure attachment on development?

It forms a foundation for social and emotional relationships later in life.

What is the relationship between HOME scores and child development?

Higher HOME scores predict better language development, literacy, and IQ scores at later ages.

What is the significance of the heritability of height?

Height has a heritability of about 90%, but is still influenced by environmental factors like nutrition.

What is the correlation between parental IQ and child outcomes?

Research shows that higher parental IQ is associated with better outcomes for children.

What does the term 'nurture' refer to in the context of development?

The environmental influences that shape an individual's development.

What is the role of genetics in psychological traits?

Genetics influence all psychological traits, as evidenced by heritability estimates.