Nature vs Nurture

Nature vs Nurture Continuum

  • Nature:
    • Biological factors have the strongest influence on development.
    • Capabilities/limitations are innate.
  • Nurture:
    • Environmental factors have the strongest influence on development.
    • Environmental influences: family, school, peers, culture.

Nature vs Nurture Debate

  • Debate:
    • How do biological factors interact with environmental events to determine development?
    • Is development mostly influenced by genetics (nature) or environment (nurture)?
  • John Locke:
    • Rejected the idea that children are miniature adults with innate abilities.
    • Newborn mind is a 'tabula rasa' (blank slate).
    • Knowledge comes through sensory experience.
  • Charles Darwin:
    • Theory of evolution emphasized natural selection and inherited variations.
    • Led theorists to emphasize heredity.

Importance of the Debate

  • Implications for schooling and parenting.
    • Nurture perspective: parents can completely shape children’s behavior.
    • Nature perspective: parental influence on improving behavior is limited.

Current Stance on the Debate

  • No clear conclusion.
  • Evidence supports both nature and nurture.

Concepts

  • Stages:
    • Children go through the same stages in the same order.
    • Behaviors are organized around a dominant theme and are qualitatively different at each stage.
    • Environmental factors can influence the rate of development, but not the order of stages.

Maturation

  • Emergence of individual and behavioral characteristics through growth processes over time.
  • Genetically predetermined innate characteristics develop.
  • Follows a fairly fixed schedule.
  • Relatively independent of external events.

Motor Development

  • Development of bones, muscles, and movement ability.
  • Almost all children go through the same sequence.
  • Occurs at different rates.
  • Practice/stimulation can accelerate onset.

Speech Development

  • Infants learn to speak after reaching a certain neurological level.
  • Environment affects the rate of skill acquisition, but not the ultimate skill level.

Critical Periods

  • Crucial time periods for specific events to occur for normal development.
  • Example: Cataract removal before age 7 for normal vision development.

Sensitive Periods

  • Optimal periods for specific development.
  • If behaviors are not established, they may not reach full potential.
  • Examples:
    • First year of life for attachment.
    • Preschool years for intellectual development and language acquisition.

Gender Differences

  • Sexuality: men report more interest in sex.
  • Physical aggression: men are more physically aggressive.
  • Cognitive abilities: males excel in math and spatial abilities, females in verbal skills.

Gender Differences - Perspectives

  • Biological: Focuses on sex hormones (estrogen and testosterone) and their impacts during prenatal development and puberty.
  • Environmental:
    • Males and females have different life experiences due to socialization.
    • Gender Roles: Sex-typed behaviors promoted by social learning.
    • Gender Schemas: Beliefs about men and women.
  • Biosocial Theory:
    • Interaction between biological differences and societal expectations.
    • Biological predispositions lead to a division of labor, but culture strongly affects work roles.

Studying Nature vs Nurture

  • Family studies: Estimate genetic influences through similarities of family members.
  • Twin studies: Compare identical and fraternal twins.
  • Adoption studies: Compare twins and siblings reared together vs. those separated by adoption.

Nature Research

  • Identical twins are more similar than fraternal twins, indicating genetic factors.
  • Monozygotic twins raised apart are almost as similar as those raised together.
  • Monozygotic twins reared apart have an equal chance of being similar in terms of personality, interests and attitudes as the ones raised together.

Twins and Adoptees

  • Genetic factors account for differences in intelligence, abilities, criminality, interests, and aggressiveness.
  • Genetic component to psychological disorders.
  • Genetic link to attitudes.
  • Identical twins receive more similar treatment from parents compared to fraternal twins.

Environmental Influences

  • Genetic differences typically account for less than 50% of variation in personality.
  • Similarities in identical twins raised apart may be due to similar adoptive families.
  • Adoptive children raised in the same house had similar IQs, even without genetic relation.

Evidence for Nurture

  • Studies of neglected infants and feral children.
  • Lack of care and attention in early years hinders development.
  • Supportive environment encourages development.
  • Environment triggers gene expression for particular traits.

Modern View

  • Nature and nurture interact continuously to guide development.
  • Brain development is influenced by genetic factors and environmental stimulation/deprivation.
  • Newborn brain has 100 billion neurons with few connections.
  • Connections develop rapidly after birth.

Conclusion - Interactionism

  • Genetic influences can be expressed differently in different environments.
  • Genes may provide an advantage, but a nurturing environment is needed.
  • Children in the same family differ due to different experiences.
  • Both nature and nurture influence development, with varying predominance.
  • Heredity and environment cannot be separated.