Intelligence Flashcards
Defining ‘Intelligence’
Pretty impossible, but it’s usually emphasised that it is:
1) a general capacity
2) independent of emotion, motivation etc.
3) a trait, rather than a state
Assumes individuals perform at their maximum ability
Where intelligence fits in Psychology
Differential psychology / individual differences
Invoked to explain performance variations across individuals
Two kinds of IQ scores
Ratio IQs: mental age
Deviation IQs: age-group relative
Heritability of intelligence
50%
Varies across lifespan: childhood 20% -> adulthood 80%
‘Faculty Psychology’
Outdated model. In Franz Gall’s ‘cranioscopy’: he thought each intellectual ‘faculty’ has a dedicated ‘organ’ in the brain
Three Theories* of Intelligence
1) Resources
2) Efficiency
3) Different strategies
[More like ‘ways of looking at it’ than theories…]
1) Neural Resource theory of intelligence
Amount of cognitive work achievable by one unit of ‘neural resources’ [whatever that means] is constant
So ⬆️ resources = ⬆️ cognitive performance
Evidence(?):
Positive correlation between relevant brain activity and working memory task performance
2) Efficiency theory of intelligence
Resource consumption is key. How little can you get away with using?
Evidence(?):
Negative correlation between visuo-spatial brain area activity and task performance (mental rotation of shapes)
3) Different Strategies theory of intelligence
How resources are used is key
Evidence(?):
Using techniques like mind palaces is great for memory task performance
WAIS IV (Wechsler Adult Intelligence Scale)
Most influential test of overall intelligence, producing one IQ number
Hierarchical structure
Structure of WAIS IV
Small subtests are grouped together into 4 indices:
i) Verbal comprehension
ii) Working memory
iii) Perceptual organisation
iv) Processing speed
i) + ii) –> Verbal IQ
iii) + iv) –> Performance IQ
VIQ + PIQ -> Full-scale IQ
JDH’s spicy take on WAIS IV
It’s a pile of shit
Ignores ontologies: what kinds of abilities are there in the first place?
Chosen subtests seem arbitrary and overlapping
e.g. ‘verbal comprehension’ tasks need working memory
Some are also just bad tests e.g. digit symbol coding
At odds with what we know about how the brain works. Inconsistencies in neuroimaging data within some subtest groups, suggests they are very different processes
Doesn’t capture what we mean when we call someone ‘intelligent’
Universal Processing Speed theory
There might be a UPS within each brain
i.e. fast nerve conduction velocity –> fast thinker
Would probably involve myelination of axons
Evidence:
IQ correlates i) positively with Peripheral Nerve Conduction Velocity and ii) negatively with (reflex) reaction times
G-Factor
Postulated by Spearman as a common factor underlying all intellectual abilities, explaining high correlation between them
(Slight) correlation between g and brain volume, especially grey matter
(But males and females equally intelligent)
Raven matrices
(Probably) the best single test to measure g
‘Choose the shape that fits the pattern’
