Intelligence part 2

Brain volume and IQ correlation + elaboration

.4, cortical S.A. may be better indicator of IQ (e.g. consider brain size of elephants)

Structures that increase cortical S.A. (2)

• Sulci + gyri

Correlation between myopia + intelligence, elaboration, note + possible explanations (2)

• Positive correlation (r = .57)

• Degree of severity of myopia does not correspond with intelligence (non-linear)

  • Threshold effect observed: no significant differences in IQ scores for myopia beyond -2.0 dioptres

• Both traits are heritable (myopia: 85%, intelligence: 47%)

• Small but significant genetic effect of intelligence on myopia, indicating possible pleiotropy for intelligence + myopia

• Other explanations, e.g. near-sighted people may not be as good at sport + thus gravitate towards intellectual activites

Heritability of intelligence (1→1)

• 47% (Williams et al., 2017)

  • Roughly ½ genetics ½ environment

Wilson effect description, possible causal mechanisms (2) + implication (1)

• Heritability of intelligence increases with age

• Likely due to:

  • Increased autonomy in environment selection (individuals select environments suited to their genetic predispositions to amplify them)

  • New gene activation during puberty

• Genetic factors increasingly influence cognitive abilities as we age

Gender differences in intelligence (1) + note (1)

• Males tend to perform better on mental rotation tasks (approx. 10 IQ points higher)

• Interestingly, was reduced when using pellets instead of cubes + eliminated entirely when using female-oriented images (e.g. prams)

Racial differences in intelligence (1→1) + possible mechanism (1)

• Best estimate today suggests that Black Americans have 10 IQ points lower on average than white Americans (+ this gap is decreasing)

  • Small difference → so much overlap that more relevant to focus on individual rather than group differences

• Research suggests that environmental influences may account for significant part of this gap (as opposed to genetic influences)

Perception of a person’s IQ (1)

• People who were glasses are perceived as more intelligent

Attractiveness + of IQ, note → explanation

• Intelligence ranks highly in terms of attractiveness in mate (sexual + partner attraction), however kindness + personality usually ranked higher

  • Threshold effect observed: slight decrease in rated attractiveness from 90-99th percentile

    • May be attributed to stereotypes of social skills of people who have very high cognitive intelligence

Emotional intelligence (EI) def + note on measuring

• The ability to recognise, understand and manage our emotions as well as recognise, understand and influence the emotions of others

• Difficult to develop good quality measures (self-report tests to be used with caution due to self-bias)

Attractiveness of EI (2)

• Rated as more attractive than cognitive intelligence, but still lower than kindness + understanding

• No threshold effect observed

Sternberg’s Triarchic theory description (1→3) + disadvantage (1)

One model of intelligence with 3 primary dimensions

• Analytical intelligence: problem-solving, analysis + critical thinking

• Creative intelligence: developing novel ideas, dealing with new situations

• Practical intelligence: ability to shape, adapt to and select environments to achieve one’s goals

• Downside: least empirical support compared to other theories

Flynn effect description (1→1) + important note

• Rising IQ scores observed in developed countries during 20th century (but not in memory span)

  • Slowing trend/reversal observed in recent last 25 years

• Research is very messy in this area, may be related to test-taking ability, social + educational influences etc.

The influence of education on intelligence (1)

• Research suggests formal education may increase intelligence

Intelligence vs expertise (1→1)

• Training can increase expertise in certain area, rather than intelligence (e.g. training digit span)

  • Due to limited ‘transfer’ of these skills to other areas

Far-transfer def (1)

Improvement on tasks taht are dissimilar to the one trained, often involving different skills or contexts (e.g. practicing Sudoku → enhances general problem-solving)

Video games + intelligence (1→1→1)

• Research is mixed but tends to show positive correlation

  • Seems to be due to a correlation with higher processing speed, as opposed to fluid or general intelligence

    • Q. What is the direction of the relationship? (i.e. does playing video games improve processing speed, or do people with better processing speed gravitate toward playing video games?)

Intelligence def + notes (2)

“A human’s maximal capacity to achieve a novel goal successfully using perceptual-cognitive processes” (Gignac & Szodorai, 2024)

• Novel = cannot have previously encountered task

• Perceptual cognitive processes include attention, visual + auditory perception, sensory integration

Artificial intelligence def (1) + note (1)

“The maximal capacity of an artificial system to successfully achieve a novel goal through computational algorithms

• Difference between human intelligence: perceptual-cognitive processes vs computational algorithms

Is AI intelligence (yet)? (1)

• No: large language models (LLMs) seem to exhibit expertise (from extensive training) rather than intelligence (cannot solve novel problems → no transfer)