Intelligence Flashcards
Outline some of the key definitions of intelligence.
- What an intelligence test measures
- Usually assess IQ which is standardised to mean of 100 and SD of 15
- IQ questions often depend on knowledge and culture
- Raven’s progressive matrices aim to get rid of these biases
What are the theories and models of intelligence?
General intelligence Crystal vs. fluid intelligence Biology and genetics Multiple intelligences PPIK Theory (investment theories) Trait complexes
What is IQ split into?
- Crystal (Gc) – learnt (83-93%)
- Fluid (Gf) – biological potential (7-17%)
What skills are part of crystal intelligence?
Spelling, writing and oral style.
What skills are part of fluid intelligence?
Reading speed, Piagetian reasoning, sequential and inductive reasoning.
Outline fluid intelligence.
- Focuses on process independent of context or knowledge domain
- Seen to include executive control and working memory tasks, e.g. holding objects in memory (may be referred to as fluid cognition)
- Seen as biologically instantiated in the prefrontal cortex
- Declines later in life
- Measured by Raven’s progressive matrices - fill in the gap, spatial reasoning.
Outline crystal intelligence.
- A product of Gf - Investment theory (Cattell)
- Gc test: vocabulary etc. and as such represent acquired knowledge and not ‘intelligence’
- Knowledge (acquired) increases over life
What support is there for Gf-Gc theory?
EXTRA
According to Blair (2006), psychometric data generally supports the Gf-Gc theory - neuropsychological data shows that PFC damage leaves g intact but Gf substantially reduced, Gf and Gc have different developmental trajectories, and children with phenylketonuria (PKU) show Gf deficits
Outline the Flynn effect.
A generational rise in IQ by on average of 10 points (range 5-20 points; SD = 15) which is seen across at least 14 different countries. It’s more substantial for Gf than Gc, and varies between countries - it’s highest in the Netherlands, below average in the UK, stopped in Sweden and reversed in Norway.
What is the cause of the Flynn effect?
o Social Multipliers – environmental factor that cause IQ of some to increase
Internet and information access, gaming (reaction times), schooling, group learning and studying, culture of educations
o Matching
Gene-environment correlation – people seek out environments that match their phenotype
Process by which the ability and the environment are matched produces increases in initial ability
Therefore environment increase genetic ability
o Averaging
As individual ability rises – will influence those around them
Small effect over time will influence wider population
Population average increases
Genes and environment influence each other
According to behavioural genetics, what amount of intelligence is heritable?
Heritability estimates range from .48-.62 (up to .80)
What environmental factors affect heritability of ‘g’?
- Age - h2 increases with age from 40% in childhood to 60% in adulthood and 80% in old age
This effect may represent a gene-environment correlation – genes need appropriate environments to express. High IQ people will seek out high IQ contexts so intelligence will show as they get older - Socio-economic status - heritability and socio-economic status are positively correlated - 72% of high SES, 10% for low SES
o May reflect a gene-environment interaction. More resources in high SES to allow genes for IQ to express. SES may reflect genetic effects also
What did Sternberg et al. (2005) state about the heritability of intelligence?
- Heritability doesn’t allow inference to between group differences - heritability is the proportion of individual difference variation that’s attributable to genetic variation (50% heritability doesn’t mean 50% is inherited).
- It’s a population measure – cannot be applied to individuals - if certain ethnicities score lower, may reflect cultural issue not genetics
- heritability isn’t the same as genetic influence - it’s still affected by environmental factors.
- High heritability doesn’t mean that modification isn’t possible
What brain regions biologically correlate to IQ?
EXTRA
According to a meta-analysis of brain volume:
- g correlates .33 with brain volume
- g correlates with genetically determined frontal regions (twin studies)
Grey matter (GM) positively correlated in all 4 lobes (primarily frontal) with IQ
Distributed white matter correlates but to less of an extent than for GM.
Outline P-FIT (parietofrontal integration) theory (Jung and Haier, 2007).
Sensory information is gathered and fed forward to be analysed for symbolic meaning and eventually forward for solution, reflections and evaluation
– Step 1 [sensory]: Assumes that human attend to and gather salient information via auditory and visual processes (Temporal and Occipital lobes)
– Step 2: Feed forward to parietal lobes for symbolism, abstraction and elaboration
– Step 3: Parietal cortex interacts with frontal cortex for hypothesis testing of various solutions
– Step 4: Anterior cingulate constrains response selection to inhibit competing responses
– Step 5: Steps 1 to 4 require the fidelity of the underlying white matter for error free transmission
