environmental effects and group differences in intelligence

environmental effects and group differences in intelligence

1. education

   • correlates with high IQ scores
     • both cause and effect?
       • students stay in education longer if they're smarter and staying in education longer makes them smarter
   • attendance- regular?
   • improves factual knowledge- crystallised intelligence (vocab/encyclopaedic knowledge)
   • improves abilities which contribute to intelligence
     • problem solving/abstract thinking/categorisation/attention
   • related to socioeconomic status
     • high SES= prepare children for school
       • resources & care about attendance & performance
     • low SES= lack ability to assist at school
   • interventions- aim to improve IQ in disadvantaged children
     • head start- immediate gains disappeared
     • abecedarian- encouraging results
     • criticised on methodology

2. Family

   • shared environment- grow up with siblings and share environment with factors equally influencing
   • unique environment- children treated differently or factors outside of family (peer group)
   • within factors
     • passive model
       • child is intelligent due to genes- 50% overlap with parents
       • intelligent due to genetic influences/intelligent genes
       • doesn't consider interactions in family
     • child-effects model
       • child acts intelligent= parent acts intelligent towards child= child possesses intelligence & shows intelligent behaviour
       • genetic inheritance
     • parent-effects model
       • child shows intelligence= parent responds by teaching new things= child learns more= child is intelligent
       • parent encourages intelligent behaviour- actively involved, not just genes
   • child driven effects
     • children and parents don't have uniform behaviour (behave differently to well behaved child compared to naughty child)
     • parental behaviour may encourage/discourage natural tendencies-pos/neg feedback
       • this could suppress/facilitate expression of heritable traits
   • socioeconomic status
     • parents' occupation, income, education level, community status
       • class 1- professional, 2-managerial/technical, 3-skilled, 4- partly skilled, 5- unskilled
     • IQ scores correlate with SES even when family size, finances and area is considered
     • Adoption studies- IQ increased but rank order remained stable (High SES always has higher IQ than low SES) - Duyme et al
   • family size & birth order
     • larger family= lower IQ
     • biological- low IQ = more children
     • 1st born= more intelligent (Belmont)
     • admixture hypothesis
       • must consider parent intelligence, SES, ethnicity, income (Rodgers)
       • low SES= more children
       • IQ and SES affects intelligence so must examine effect within families and across families
         • across families= firsth births contain more High SES children with higher IQ
         • should be a difference between siblings (within families) if birth order effects occur
           • effect not due to SES but interval between births- six year gap eliminates effect
     • resource dilution- time, energy, attention are finite
     • confluence- more children= less intellectual environment- reduced complexity
       • each child= more danger during pregnancy

3. outside family effects- 'more important' (Harris)

   • group socialisation
   • in/out groups
     • similar= in group. Dissimilar= out group
   • context-specific socialisation
     • older= less influenced by family & more by peers
   • outside home socialisation
     • identify with different groups- age/gender/personality/intelligence
     • group doesn't encourage intelligence= child won't aim to learn
   • perceptions exaggerate differences (females study english & males study maths)
     • group processes also exaggerate differences- viewed as intelligent= group look for guidance= has to act intelligent
   • culture
     • Western intelligence is different from other conceptualisations (Serpell)
       • Quantification/Decontextualisation/Biologisation
         • Decontextualisation- Western thinking follows ancient greek. Ability to detach self and thin abstractly. Industrial revolution & rapid change means it is important
         • Quantification- quantify intelligence. Reification- see abstract ideas as concrete. Intelligence is something physical in the brain
         • Biologisation- intelligence is due to natural selection

4. Group differences

   • differences determine beliefs/attitudes/policies
   • Eugencis- 'good race'- Galton
     • beliefs/practices which through controls on reproduction improve the inherent characteristics of the human race
     • positive= encourage reproduction of people with desired traits
     • negative- discourage/prohibit reproduction of people with undesired traits
     • laws against mentally ill, low intelligence, criminals & blind/deaf
   • Brain size
     • brain volume size correlates with intelligence

5. sex differences

   • males have larger brains (8-10%) so should have higher IQ's
   • fewer women in STEM, management
   • girls better at reasoning, language
   • boys better at spatial & mechanical
   • evolutionary explanation
     • sex differences are by-product of natural selection
       • males eith better spatial skills had greater chance at reproducing and passing on abilities
     • foraging- males main provider- navigation, aware
     • range- males seek polygamous relationship- seek females
     • warfare- males act as warriros- navigate
   • biological explanation
     • neurons are the same in both genders
     • gonadal hormones may play a role
   • environmental explanation
     • stereotypes
       • affects subject choices
     • parental views & expectancies
     • self-fulfilling prophecy
     • if environmental- changes in condition should eliminate differences

6. race

   • emerged as an ideology to justify slavery & colonisation
     • no genome signifies race
   • magnified physical differences
   • there is a 94% differrence within a race compared to 6% between races
   • mean intelligence scores of African Americans is 1SD below the mean of White Americans
     • Hispanics score between these
     • Asian-Americans score higher (less than 1SD)
   • Genetic explanation
     • individual differences in IQ are to differences in heritability of genes
     • race differences in reaction time tasks correlate with g
     • brain size differences

7. IQ scores subject to environmental change?

   • IQ scores have been gradually increasing- James Flynn (Flynn effect)
     • Gc tests (vocab, arithmetic tests) have not shown same increase
     • Environmental complexity theory
       • increased complexity and enriched social environment= increased IQ
       • small family= more child interaction= more education= better jobs
   • evidence that devoping countries are catching up with developed countries in the Raven's test

8. reaction times and brain size

   • not always given consistent findings
   • brain size has a correlation of 0.20 with intelligence
     • difference in brain size is largely due to environment (nutrition)

9. evidence for environmetnal factors

   • white mother's offered positive encouragement in teaching
   • reduce difference with training
     • provide equal exposure to unknown words to children

10. stereotype threat

    • fear of being reduced to stereottype
    • triggered by situation- when told a maths test identified sex differences women performed worse
    • black students perform differently when told a test identifies intellect
      • black students perform worse when race was primed