Mandy Part 2 Flashcards
The shared genes w diff types of relatives
1st degree e.g. parents, share 50%. Second degree e.g. grandparents share 24%, 3rd degree e.g. great grand parents share 12.5%
Galton, initial ideas of heritability
Intro idea of nature nurture, in relation to Darwin. Looked at ppl doing eminent things in newspapers and found no. Of eminant relatives greater for 1st degree than 2nd. Also looked at environment at royal society members and asked them about their upbringing. First to suggest twin and adoption studies
Variability defining one
If parents and child v similar, low variability and high prop of shared variance, opposite of different
Some traits 100% genetic, shared high and no variability but others differ
Diff ways of measuring
Behavioural approaches like family studies or dna approaches. Use behavioural to estimate heritability across populations W shared variance but not ind. say proportion of variance for intelligence due to genetics. Ridley 99: meta anal found more shared genetics, more heritability of intelligence e.g. mz twins, then twins apart, siblings. Eyesneck said 69% and bell curve 74%
Dna methods
Genome wide association study looks at total dna for one group, look for single nucleotide polymorphism (SNP) the variations that may occur in certain groups. Deary 2012- did the Scottish kids one also used lots of unrelated ppl and found heritability 38% but differs across life and culture. Davies 2011: found 40-50% variance linked to SNP they had in common. Deary, cox and bull 2021: lit review heritability is 20-30% (less than before)
Concepts definition for nature nurture ideas
Interactive not additive model, includes genetic variation, assortative mating, twin studies and environment. Abstract concepts: theoretical, don’t tell us about spec genes or environment variables. Population concepts: estimates for group, don’t say about ind
Types of genetic variance and assortative mating
Genes and environment = phenotype. dominant= either dom or rec. epistasis=genes interact w others to determine if they are expressed or suppressed. Add these all together- get broad heritabiltiy. Variation in traits is bc mating isnt random so may over/under estimate heritabilty
Environment
Bio (nutrition, lead, prenatal), fam environment, education, culture. Birth order and fam size: Belmont and marolla 73: as both increase, intelligence decrease. Fridges 2000: longit study in us found no link. Dodgers 2001: admixture hyp, resource dilution model-Galton, confluence model (not birth order but the changes that occur within the home). Bidirectional as iq predicts school but school helps iq (linked to implicit theories)
The bell curve - Hernstein and Murray
6 assumptions: G exisits, iq tests are accurate, iq tests match implicit theories, iq is stable and tests not bias, cog heritability no less than 40-80%. Suggested cog elite e.g. some go to college some don’t. Said intell more important than SESnfor predicting welfare. Higher iq of Asia in American Han black. Low iq women have more kids so pollut pop W low iq, say immigrants fault too and increases crime. To stop: don’t use affirmative action as lead to decrease intell but give resources to elite
Bell curve critiques
No consensus on G, iq tests not always accurate and shift between cultures, iq not stable. Tests may be unbiased but theories are. Heritability has a large range and can’t explain group diffs. Correlation isn’t causation for SES and intelligence (other factors), used self report to ask kids what SES they were. Said research showing black ppl as intelligent was inconsistent and removed it - karmin 95. Led to APA make task force led by Neisse - consensus that iq may differ across groups but not due to genetics
Background sex diffs in intell
Suggest men better bc brain bigger but research says no diff. Terman-Stanford binet show girls slightly better. Spear a no diff and court 83: systematic review found no diffs. But used narrative anal where just say if supports hyp or not and small samples. Lynn and irwing: did meta anal (compile samples together) found under 15 no diff, then bigger diff as get older in favour of males but not huge effect sizes
Evaluation
Nyborg 2005: advantage for males- supporting last also in meta But colom 2000 and spinath 2008 didn’t find any diffs-disputes.Dykiert 2008: and hunt and madhyastha 2008: reported diffs due to unrep samples as males more represented in the samples.Hyde 2005: comp review and found no diffs
Specific intelligence sex diffs
Maccoby and jacklin 74: men do better on spatial , women do better on verbal. Different meta anals find some diffs but more when younger. Small effect size that females better at verbal but not as robust evidence as for spatial diffs
Sex diffs in gifted children -Benbow and stanley 83
12-14 who took sat early. No diffs in verbal but boys did better in the maths section as 13x as many W scores of 700+, 4x scores over 600. But gap now closing as now 3:1 due to efforts to get women in harder maths and science
Bio explanations- brain size
Men’s 10% larger from adolescents onwards (explains old findings). But pietschnig 2015 mata anal found sig link between seize and intell but only small proportion of variance. Inflated due to republication bias
Brain structure
Tasks solved more efficiently when carried out by one side of the brain.Allen 91: females have bigger splenium, steinmetz 95: females have bigger cc-may mean tasks more evenly split over hemis .Supported idea fem brains more bilaterally org in rep of cog function
Brain functioning
Grey matter processing info/White matter transport info. Haier 2005: mri, iq among fem related to more white matter and fewer grey matter than males. Iq in males, more in grey and fewer white Males and females get same iq using diff parts of the brain, intell in males may be linked to info processing, links to better spatial ability
Hormones
Test related to higher performing on spatial ability tasks. Choi and silverman 96: ps given fake map and told to learn shortest route then give directions. Females gave relative directions to landmarks , males gave distance and cardinal directions- t correlated among males to using these directions more. Barry 2013: females W pcos scores higher than controls on mental rotation tasks
Evolution
Males needed for spatial for hunting, warfare , women didn’t as gathered over small areas and restricted due to pregnancy and childcare. Jones 2003: males W more spatial more likely to win wars, supply food and maintain relationships , more attractive so pass on. But all speculative, don’t know if ability or hunting came first, ignores how women would travel in diff seasons and how they hunted
Controlling for nature
Hoffman 2012: looked at spatial ability in two genetically related tribes but diff environments-should have no diffs if just bio
In patriarchal-women took more time to solve puzzle but in matriarchal- performed no diff to men, and both took shorter than in patriarchal
Toy differences
Boyd play w toys that encourage spatial awareness skills e.g. lego
Campbell et al 2000: toy preferences reflect gender stereotypes as young as 9m old
Feng 2007
Tested spatial attention and mental rotation among gamers/non gamers in m and f. Gamers did better than non, no sex diffs in gamers but in non, males did better. Then did either action video game training or non action training. All in action improved, females more than males. No sex diffs after action training. In control, m did better pre and post
Where stereotyping comes from
Reinforcing: langloid and down 80: parents reinforce behaviour and discourage sex inappropriate behaviour.Modelling-more implicit: children observe same sex others and how they should behave. E.g. what toys to play with .Socialisation: entwistle 94: boys given greater freedom to explore
Toy studies -stereotypes
Bbc docu : dressed boys and girls and girls as boys. Found strangers directed them to the toys they thought girls/boys should play with and reinforced. Seavy katz and zalk 75: same
Found adult ps w boy, 50% adult male and 80% chose football. When playing w girl, 88% adult man -and 72% women chose doll for girl to play with -sidorowicz and lunney 1980
Culture and global inequality
Gender stereotypes the same across 25 countries - asked for words associated e.g. active, ambitious, strong for males but emotional, shy and mild for women. nations w greater gender equality show smaller gender diffs in maths performance
Education
Hyde : no diffs in maths performance but had more females?, no diff in understanding concepts and problem solving until high school and college then men better-small effect size. Replicate found high school m better problem solving. Girls don’t choose stem as seen as masc so less likely to get spatial skills (21% f in physics alevel). Moss 2012: rated applicant more competent when male name for lab manager
Effects of stereotype in school
Spencer 99: m and f took math test, then half told m scored better in past- then f scores worse. Inzlicht : ps did maths and verbal tests either W two females or 2 males- worse scores in maths test when minority- no diff in verbal
psychobiological/psychosocial model
And W
Nature and nature: don’t know if bio diffs create stereotypes, stereotypes can be accurate?. Olsen 2013: mental rotation given to f and m, given on either small screen or large screen. F did better on large screen but males on small scree as men use holistic view , women use step like review . More now in maths Olympiad
Tutorial
Internal: do diff items correlate W each other (measuring same construct). Cultural context to what intelligence is. Sternberg: used to be just white males taking test, scores correlated with SES. The rainbow project: cut bias , kaleidoscope project (by measuring creative, practical wisdom based they could improve prediction of academic). Tests miss out other forms of intelligence , ppl who do well keep at the top, harms ppl wout these skills
