Karteikarten
Chap 11 - Heredity IQ
Karten in diesem Stapel (32)
- 1Measuring intelligence 1- Alfred Binet (1857-1911)
- Measured children's potential
- Genetic general intelligence
- Educational service -> categorisation
- Predict the effect of tuition/education - 2Measuring intelligence 2• Bias: e.g. extraversion/introversion
• Test should rely on practical knowledge or experience
• Speed
• Control for age
• Calibrated to 100 +/- 15
• IQ = ?????? ??? ∗100 /
?ℎ??????????? ???
• 10 year old with mental age of 12: 1200/ 10 = 120
• 10 year old with mental age of 8: 800/10 = 80 - 3Normal Distribution 1- GENETIC TRAITS are OFTEN NORMALLY DISTRIBUTED
- Eg. Height - 4Normal Distribution 2IQ: 100 +/- 15
- 5IQ as a simple construct 1• g = generalized intelligence
•Argues for One single construct that influences all cognitive functioning
• Correlates highly with performance on different tests
• Should be independent from schooling
• Should be culture free
• Stanford-Binet (follow up of Binet Simon)
• Came up with Raven’s progressive matrices: series of non-verbal, visual puzzles to form perceptual relations between elements
- 6IQ as a simple construct 2- Raymond Cattell (1905-1998) constructed the:
1) Fluid Intelligence
2) Crystallised Intelligence - 7Fluid IntelligenceA fundamental factor in intelligence that represents the ability to think and reason on your feet
- 8Crystallised IntelligenceA fundamental factor in intelligence that represents the accumulated knowledge of an individual
- 9Fluid vs Crystallised Intelligence
- 10—- Fluid intelligence is relatively STABLE
- Crystallized intelligence INCREASES
across the lifespan
• Interaction:
- Better fluid intelligence
→ Easier knowledge acquisition
→ Adopt strategies to learn quicker
- 11Intelligence Test- Wechsler Intelligence Scale (WISC/WAIS)
- WISC-III/IV verbal and performance
- Separate scales combined in overall
score - Only if the two scale scores are not too far apart!
- WISC V → 5 scales
- 12Monozygotic & Dizygotic Twins
- 13Monozygotic TwinsHave the same genes and are often also live in the SAME ENVIRONMENT
- 14To assess environmental/genetic (nature/nurture) contribution in IQ...- Study MZ/DZ twins reared apart
- Study adopted children - 15IQ Correlation - Plomin & DeFries (1990)
- 16Heritability across the life span (McClearn et al, 1997)- Heritability factor INCREASES with age
How?
1. Statistical error in younger children - due to confusion from IQ tests
2. Genes may determine life experiences (vulnerability for diseases)
3. Maturation
- 17HeritabilityIs a measure of how well DIFFERENCES in people's GENES account for DIFFERENCES in their TRAITS
- 18So...IQ is mainly nature? 1 (Woodworth, 1941)- Studied MZ twins reared apart
Findings:
- Twins that are placed in SIMILAR ENVIRONMENT = SIMILAR IQ
- Twins that are placed in DIFFERENT ENVIRONMENT = DIFFERENT IQ
Conclusion:
- Twins, if reared apart are often still REARED in SIMILAR ENVIRONMENT/SOCIAL CLASS - 19So...IQ is mainly nature? 2- MZ twins share the SAME ENVIRONMENT in the womb (Devlin et al, 1997)
- Genes MIGHT INFLUENCE the treatment of a child - eg. personality, health, trigger certain responses
- Twins MIGHT HAVE SIMILAR life EXPERIENCES (personality, health) - 20Socio-Economic Status (SES) modulation of heritability (Turkheimer, 2003)- Heritability for IQ specific for children with high Socio-Economic Status (SES)
• High SES: Optimal environment
→ variance due to genes
• Low SES: environment might contribute relatively more than genes
• However, this is still under debate - 21Family Environment & IQ (Elardo, 1975) 1- Argues that there are SOME FACTORS that contribute to an ENRICHED environment:
1) Positive feeling in the mother's voice when speaking to child
2) Mother structures child's play period
3) Mother reads stories ≥ 3 times weekly
4) Family provided age-appropriate learning equipment
5) Child gets out of the house ≥ 4 times a week
6) Mother shouts relatively infrequently at the child
7) Mother relatively frequently vocalizes spontaneously to the child - 22(Elardo, 1975) 2- Studied 77 children from LOWER CLASS families
- RATED ENRICHED environment at 6 - 24 months old babies
- Tested IQ at 3 & 4.5 year olds
Findings:
- ENRICHED environment score CORRELATED substantial with later IQ (0.44 ~ 0.70)
- This relation between family environment and IQ has also been found for adopted children (Plomin et al, 1985) - 23Confluence Theory (Zajonc, 1985)- Birth order & number of siblings INFLUENCES IQ
- The 1st born child - HIGHEST IQ (decreases successively)
- IQ - HIGHER in 1 sibling than more than 1 sibling
Why?
• Emotional and intellectual attention decreases with each child
• BUT: larger families (back then) often lower SES
• AND: less money to spend per child - 24Flynn Effect 1The increase in IQ scores from 1 generation to the other, which averages about 3 points per generation & CANNOT be explained by an increase in intelligence in the population
- 25Flynn Effect 2Without IQ calibration IQ would
rise (Flynn, 1984, 1987, 1994)
Even on culture free tests (e.g.
Raven)
- 3 points per generation
- Better education
- Better nutrition (we also get taller)
- Better parenting
- However, not completely clear! - 26Does NUTRITION play an impact in IQ performance?There are contradicting findings:
• Benton & Roberts: vitamins gave an IQ gain 9 points compared to placebo
• Schoenentaler (1991) replicated this finding in the USA, but Crombie and colleagues (1990) could not replicate it
in Scotland
- Possibly, additives only improve IQ in children who previously followed an impoverished diet - 27IQ, elitism & racism 1 (Herrnstein & Murray, 1994)- Claimed that the CORRELATION between LOW IQ, poverty, etc is GENETICALLY determined
Findings:
- IQ US black children < white children
- Overlaps
- Gave a distorted picture - 28IQ, elitism & racism 2 (Ogbu & Stern, 2001)Implied that the average IQ gap between US black children and white children began to NARROW
- 29IQ, elitism & racism 3- Cultural differences in concept of IQ/cognition (Nisbett, 2003)
- IQ tests are CULTURALLY BIASED
- Not even stable between generations! - 30—• IQ scores CORRELATES with SCHOLASTIC experience
• IQ is a 'WESTERN’ measure
• Very sensitive topic
- 31Summary 1• IQ IS largely heritable - But also environmental influences
• Interaction: genetic factors influence experience (personality, curiosity, temperament, extraversion)
• Environment might ‘trigger’ genes
• Covariance: Intelligent parents provide an enriched environment AND might have a higher SES
• Transactional: Intelligent and healthy children might trigger positive responses that, in turn, positively influence their cognitive development - 32Summary 2• Intelligence based on:
- Single construct g
- Flynn effect: IQ is not stable over generations
- Genetic & environmental factors
- Diet end nutrition
- Family environment
- Measures are mostly ‘western’ hence not culturally insensitive
Informationen
- Beschreibung
- undergraduate Developmental psychology Karteikarten am Chap 11 - Heredity IQ, erstellt von Izati Saim am 19/01/2022.
- Erstellt von
- Izati Saim
- Aufrufe
- 0
- Bewertung