intelligence Flashcards
(44 cards)
1
Q
define intelligence
A
involves the ability to reason, plan and solve problems, think abstractly, comprehend complex ideas, learn quickly and from experience
2
Q
Francis Galton
A
- first attempt at IQ test
- hypothesised intelligence correlated with observable traits such as reflexes, muscle grip, and head size
- hereditary genius - eugenics - race betterment
- positive eugenics - encouraging healthy capable people from above-average intelligence to bear more children
- negative eugenics - involuntary sterilisation or institutionalisation - targets minorities such as immigrants, physically and mentally ill and the poor
3
Q
Charles Spearman
A
- noticed positive correlations between students’ performance in different subjects
- used factor analysis on an array of different tasks with an element of cognitive difficulty
- confirmed the g factor
- accounts for 50% of variance in IQ test performance
4
Q
how is intelligence measured? alfred binet
A
- objective way to identify children who needed additional help
- believed intelligence tests were not generalisable and could only apply to children of similar backgrounds and experiences
- created the WAIS - weschler adult intelligence test
- contained multiple different subtests
- verbal comprehension, perceptual reasoning, working memory, processing speed
- had a hierarchal system
1) individual tasks - showed specific ability to do well on specific task
2) these individual tasks were trios and fed into 5 groups (listed above) - narrower types of mental ability
3) general intelligence - general mental ability to do well on all tasks
5
Q
is spearman’s g a cross-cultural phenomenon?
A
- Warne and Burningham 2019
- found a single factor emerged unambiguously from the majority of samples
6
Q
Bouchard and McGue 1981
A
- parent and child and sibling correlations to suggest a genetic component to intelligence
- does suggest a correlation
- possible explanations:
1) hereditary - genetics
2) nurture - high IQ parents transmit high IQ through nurturing their children
3) shared environment
4) combo of all
results - if purely down to genetics MZ twins would have a correlation of 1.00 actual correlation was 0.86
- DZ twins expected correlation of 0.50 actual correlation was 0.60
- suggests role of environmental factors
7
Q
heritability estimates for intelligence
A
- haworth et al 2010
- used web based cognitive tasks - ravens matrices and weschler
- MZ twins = 0.76
- DZ twins = 0.49
- 2 x (0.76 - 0.49) = 0.54
- 54% of variance in IQ attributed to genetic variation
8
Q
variation of IQ heritability across social groups
A
- analysis of WISC scores from MZ and DZ twins
- additive effects of genotype, shared environment and non-shared environment interacted with SES
- proportions of IQ variance attributable to genes and environment vary nonlinearly with SES
- lower SES families = 60% of variance in IQ scores accounted for by their shared environment with the contribution of genes close to 0
- opposite for higher income families
- as SES increases, heritability goes up and environment goes down
9
Q
IQ increasing heritability across the lifespan
A
- from childhood to adolescence to young adulthood heritability increases and shared environment decreases
the wilson effect - MZ twins become increasingly concordant with age and their development is parallel
- DZ twins become less concordant and begin to match their singleton sibling just as closely as one another
- mental development is guided by scheduling of genetic programming acting in concert with maturational status and environmental influence
10
Q
why do genetically driven differences increase with age?
A
the multiplier effect
- genetic tendencies that guide behaviour will result in a change in the environment that magnifies the original tendency
- a clever child being sent to private school
11
Q
Davies et al genetics and SNPs
A
- looked at the probability of each SNP being associated with general intelligence
- tested 22 chromosomes
- 11600 significant SNPs which were associated with variation in IQ scores
- 434 of these SNPs were independent and located on 148 regions along the 22 chromosomes
- looked at whether variation of the SNPs across whole genes were associated with intelligence
- SNP variation on 709 genes were associated
- intelligence is a polygenic trait, that is associated with a great many genetic variants in many genes, and in many DNA locations that are not genes
- accounted for 25%
12
Q
what are the affects of gene and DNA variations?
A
- several are related to the development of nerve cells and nervous system
- some DNA SNPs variations appear to also be related to health
13
Q
correlates of g - nerve conductivity velocity
A
- measured by applying a burst of current through skin over a nerve and picking up its time of arrival further up/down the nerve
- correlation with g
14
Q
correlates of g: inspection time
A
you see a pattern for a very short period of time - 50ms or less - followed immediately by a mask then have to identify it as one of two possible shapes
- higher IQ participants are faster
15
Q
correlates of g: reaction time
A
- zeros appear in the box in the top left-hand corner
- participant task is to press the button corresponding to ‘0’ every time a 0 appears in the box
- time taken directly correlates with IQ
16
Q
what are global determinants of navigation ability?
A
- spatial ability of a population is correlated with economic wealth
- gender inequality of a country is predictive of gender differences in navigational ability
- a city with higher entropy is more complex, those who grew up outside of a city had better spatial awareness due to the complexity
- better at navigating environments similar to where you grew up
17
Q
what is the firstborn advantage?
A
- first born children tend to have a cognitive advantage over their younger siblings
- systematic shifts in parental behaviour and home environment when going from parenting one child to multiple
18
Q
describe the sample from the national survey of youth 1979 and how this data has been used
A
- 12686 youths born between 1957-1964 tested at 14yrs-22yrs
- info of their employment, income, welfare program participation, and education was collected
- these people were then re-found in 1986 and their children were interviewed bi-annually
- the surveys these children took part in involved scores on cognitive and non-cognitive assessment, prenatal investments, birth outcomes, early children parental investments and health, home environment etc
findings - parents unable to provide for later born children to the same level of cognitive support as their first born
- systematic differences in maternal behaviour
- as early as 1yr later-born children score lower on cognitive tests than siblings and this gap increases until school entry but remains significant after
19
Q
how is breastfeeding related to cognitive development
A
- angelson 2001 = children breastfed less than 3 months had an increased risk compared to children breastfed for 6 months + of a test score below the median value on scales of infant development
- Deoni 2013 - by age 2 improved receptive language scores and enhanced development in key parts of the brain associated with higher-order cognition in breastfed children
- extended breastfeeding (>15 months) was positively associated with greater myelination in the somatosensory, auditory and language areas
20
Q
what are the long term effects of breastfeeding?
A
- Victora et al 2015 – long term consequences on IQ years of schooling and income at age 30 yrs. Information from 3439 individuals on IQ and breastfeeding – in Brazil
- those breastfed for >12 months have 3.76 IQ points advantage, 0.91 years more of education and higher monthly incomes than those breastfed <1 month
21
Q
what are some factors that can affect IQ in early years
A
- low birth weight = peak for IQ is lower than the average IQ when mapped against birth weight - moves average from 100 to 80-90
- general anaesthesia = when outcomes compared to biological siblings no adverse developmental outcomes were found. But Glatz found that exposure before 4 was associated with 0.97% lower IQ
- chemotherapy = literature review (across 10yrs) found adverse neurocognitive effects however better of two evils - great health benefits
- toxic waste sites = nothing really developmentally good about this so obviously bad for IQ
22
Q
the flynn effect
A
- IQ scores improve across generations
- seen greatest in fluid intelligence tests (raven’s matrices) than fluid and crystallised intelligence tests (weschler and stanford-binet)
- not due to education as appears in infants
23
Q
what is the anti-flynn effect?
A
- the early, large gains are not evident at more recent time points
- evidence of IQ decline across later generations
24
Q
what are the two explanations for the flynn effect
A
1) could be due to practices or valuation of abstract thinking. improved education, nutrition and a reduction in pathogen stress support opportunity to abstractly think
2) is a transient phenomenon that reflects a boost in IQ driven by environmental factors that were masking:
–> underlying dysgenic trend - more intelligent people having less children
–> compositional change from immigration
–> anti-flynn effect attributed mainly to genetics and immigration
25
how were the dysgenic fertility and compositional change from immigration hypotheses disproved?
- population-covering data registers of IQ scores from Norway across 30 birth cohorts
- within-family variation fully recovered both the timing and magnitude of the effect
- Disproved the dysgenic fertility and compositional change from immigration hypotheses
- Causal factor of the Flynn effect must be environmental
26
how does IQ contribute to learning?
- IQ and academic achievement strongly related however, educational attainment is a stronger predictor than IQ of occupational success and income
- relationship between intelligence and academic achievement was stronger when students scored higher in conscientiousness and lower in neuroticism
27
working memory versus intelligence
- are these names for the same construct?
- simple short term storage component and focus of attention accounts for the relationship between working memory and 'g'
- working memory and fluid intelligence contribute to reading speed and comprehension
- working memory predicts 65% of variance of g in 4th and 5th grade children
- g is a better predictor of achievement than working memory in 6th and 8th grade children
- working memory at 5 is the best predictor of literacy and numeracy 6 yrs later
28
are individual differences in intelligence stable across the life time?
- scottish survey sample used again
- 73 of the original sample re sat the same intelligence test they had sat at 11yrs
- those who scored better compared to their peers in 1932 also were the better scorers in 1998
- correlation = >0.6
29
factors affecting cognitive decline
early life = less education
midlife = hearing loss, traumatic brain injury, hypertension, alcohol, obesity
later life = smoking, depression, social isolation, physical inactivity, air pollution, diabetes
30
what is cognitive reserve?
- some people cope with cognitive decline, brain has the ability to still function after cognitive development or even damage
- speaking multiple languages can contribute and strengthen the reserve
31
educational outcomes and IQ
- Intelligence and educational achievement – Deary et al 2007 5 yr prospective longitudinal study of 70,000 english students
- IQ at 11 was a powerful predictor of educational attainment at 16 accounting for over half of differences in GCSE scores
- significant amount of variation not related to this
- g proved to be strongest predictor of school achievement (science)
- for maths and English a child's ability for self-perceptions more important
32
job success and IQ
- psychometric intelligence tests almost as strong of job success as work sample tests and employee interviews
- intelligence tests are also good predictors of job progress
33
what does emotional intelligence predict?
- better social and work relationships
- recognise and reason about emotional consequences
- lower scorers on measures of distress symptoms
34
health and intelligence
- intelligence related to longevity
- studied 1 million Swedish men; 20 yrs of follow-up
- every SD in IQ was associated with 32% decrease in mortality risk 20yrs later
- higher IQs led to increase in life expectancy
35
IQ and mental health
- lower childhood IQ is associated with an increased risk of:
1) schizophrenia
2) PTSD
3) Depression
- a SD increase in IQ score in youth is associated with a risk reduction of between 13-43% in mental health difficulties in adulthood
- Higher childhood intelligence was significantly associated with reduced risk of self-harm but was not significantly associated with suicide risk
- ball et al 2025 - used the scottish survey sample again and health data from hospital admissions between 1980-2020. found higher childhood intelligence associated with reduced risk of depression in later life
36
how can common IQ tests be adjusted for neurodivergent individuals?
- colourblind versions
- visual/auditory versions
- (WAIS-V) clinician can skip some tasks
37
what was Wilson (2023) meta-analysis?
- data from 1800 neurodivergent people
- autism and ADHD
- children and adults
- autism performance
--> verbal and nonverbal reasoning: in typical range
--> processing speed ~ 1 SD below mean
--> WM slight reduced
- ADHD performance
--> mostly at age-expected levels
--> WM = slightly reduced
38
the relation between brain size and intelligence in humans
- no strong enough evidence
- 2005 meta-analysis = found no studies with a strong positive correlation (0.3-0.4)
- another systematic review found positive correlations across 88 studies, however, did have pub bias and omitted studies with small/non-sig associations
39
does more brain volume (more brain cells) associated with a higher IQ
- post-mortem brains from 50 Danish males with premorbid IQ scores
- is IQ correlated with number of brain cells or brain weight
- no correlation between IQ and brain cells
- weak correlation between IQ and brain weight
40
brain size/IQ and sex differences
- adult male brains 10% larger vol. than women
- clear absence of sex differences in IQ
- therefore, larger brains do not = higher IQ
- structural roots of intelligence may differ by gender --> women higher IQ = more grey and white matter in frontal language areas --> men = higher grey matter volume in sensory integration areas
41
do some people just have more efficient brains?
- participants after learning a complex visuo-spatial task -tetris- had a decrease in cerebral metabolism after practice
- after learning to play tetris there was a more pronounced decrease in cerebral metabolism in higher IQ participants
- another study found that there were significant correlations between maths scores and glucose metabolism in temporal lobes in males but no correlations in females
42
how does fronto-parietal grey and white matter efficiency differentially predict IQ in males and females?
white matter
- males = no correlation with IQ
- females = positive correlation
grey matter
- males = positive relationship between FP grey matter volumes and IQ
- females = total grey matter vol. did predict IQ, but regional vol not evident
43
Finn et al and connectivity of brains
- fMRIs from 126 Ps
- 6 imaging sessions with a mix of rest and complex cognitive tasks
- functional connectivity patterns - whole brain and 10 networks
- individual connectivity patterns stable across all conditions
- patterns in frontoparietal network most distinctive
- appeared to be able to predict fluid intelligence levels
44
what is connectotyping?
- describes pattern of brain activity that characterises how each person's mind works
- variation occurs within brain's most sophisticated networks
- stable over time
- familial and heritable
