Heredity vs. Environment in Intelligence

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Heredity vs. Environment in Intelligence

• ED PSYC 302

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Intelligence

• Intelligence is a concept that involves all
  types of cognitive processes
• Traditionally cognitive psychologists have
  viewed intelligence as
• Learning from experience and adapting to the
  environment
• Understanding and controlling ones own cognitive
  processes

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Heredity vs. Environment

• Nature vs. Nurture
• Sir Francis Galton
• Sir Francis Galton in the late 19th Century
  studied family histories and concluded that
  success eminence ran in families over
  generations
• Galton discounted the advantages of superior
  schooling and social advantages and proposed that
  eminence ran in families because intelligence was
  passed from generation to generation.

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Sir Francis Galton

• Galton published his findings in his 1869 book
  Hereditary Genius and is credited with coining
  the term nature vs. nurture.
• Although Galtons tests for intelligence were
  not successful he created an interest in
  intelligence that eventually set the stage for
  breakthroughs by subsequent investigators.

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Heredity Intelligence

• Intelligence is clearly a family characteristic.
• Heritability accounts for considerable amount of
  total variance in general cognitive ability.
• Different cognitive abilities are influenced by
  same genetic factors

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Heredity Intelligence

• Genetic research has made important discoveries
  during last few decades.
• General cognitive ability g
• g runs in families
• Adoption twin studies
• -identical twins reared apart are almost as
  similar for g as identical twins reared
  together.
• -Galtons twin studies in 1876- studied how
  similarity of twins changes over course of
  development
• -heritability increases from infancy to
  adulthood

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Heredity vs. Environment

• Both Environment Heredity are important in the
  development of intelligence.
• The epigenetic model proposes that an
  interaction of both environment and heredity is
  necessary for an individual to achieve their full
  potential.
• However, Twin Studies do support the hypothesis
  that intelligence is a genetic characteristic

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Twin Studies

• Identical twins tend to have more similar IQ
  scores than fraternal twins do.
• This is also true when identical twins are
  raised in different homes.

• Cognitive development of adoptive children more
  closely resembles that of their biological
  parents than their adoptive parents.

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Heredity vs. Environment

• Theorists believe it is ultimately impossible to
  separate the effects of heredity environment.
• Together, heredity environment influence
  development IQ in ways that will probably never
  be separated.

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Environment Intelligence

• While nature may supply some parameters of
  intelligence, it is what we do within and
  around those parameters that makes a real
  difference to learners.
• Relationships and activities a child has in
  his/her immediate environment is driving force
  behind effective human development.

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Non-genetic factors

• Parenting styles
• Nutrition
• Exposure to illness
• Parental educational level
• Environmental crowding
• Security of attachment to caregiver

• Access to stimulating enriching experiences
• Access to sources of knowledge
• Level of social support
• Noise level
• Schooling
• Stability of neighborhoods

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Environment Intelligence

• Environment clearly has a big effect on IQ scores
• Poor nutrition in early years of development
  leads to lower IQ scores.
• Mothers alcohol use during pregnancy leads to
  lower IQ scores.
• Attending school positively effects IQ
• Families and cultures in which children are
  raised have a significant impact on the cognitive
  abilities children acquire.

Mental Age IQ __________________ x 100
Chronological Age
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Environment Intelligence

• Permanently changing a childs environment from
  impoverished to enriched and stimulating can lead
  to increases in intelligence scores up to 20 to
  25 points.
• Slow but steady increase in the populations IQ
  scores due to better
• -nutrition
• -schooling
• -stimulation (TV and Reading materials)

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Racial / Ethnic Groups Intelligences

• Studies have shown considerable IQ differences
  between African American and Caucasian children.
• Due to the environment
• -economic circumstances affecting quality of
  prenatal postnatal nutrition
• -availability of stimulating books and toys
• -access to educational opportunities

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Racial / Ethnic Groups Intelligences

• In recent years, African American and Caucasian
  children have become increasingly similar in IQ
• Can be attributed to more equitable environmental
  conditions
• Studies show that race has no basis in biology

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Teaching/learning Process Implications

• Do not over-rely on models that assume a nature
  orientation
• Not nature vs. nurture but rather how the two
  work together
• What is inherited can be changed
• Race does not affect intelligence

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Teaching/learning Process Implications

• Learning how to Learn
• Children are more receptive to learning when they
  feel wanted and valued and environment is
  meaningful, accepting, comfortable, orderly, and
  safe.
• Active and learner centered
• Connect with schools social environment

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Sources

• Ormrod, J. E. (2000). Educational Psychology
  Developing Learners (3rd ed.). Ohio Merrill.
• Dr. Thomas Shaffer, South Dakota State
  University.
• Plomin, R. (1999). Genetics and intelligence.
  Journal of the American Academy of Child and
  Adolescent Psychiatry. 38(6), 786.
• French, F. (2003). Revisiting Nature vs.
  Nurture Implications for the Teaching/Learning
  Process. Education Canada. 43(2), 20-23.