Week 7 Flashcards
What is intelligence?
What is an argument for why intelligence can’t be defined as some particular ability?
(e.g. reason to abstract, executive function, reframe problems, etc.)
- Wall Street Journal published a book called ‘The Bell Curve’
- Statements around what was currently known about intelligence and what it was defined as
- Helpful because the statements gave a clear definition on what intelligence is
- Defined intelligence as a very general capability that, among other things, involved the ability to reason, plan, solve problems, think abstractly, etc.
- Counters the prompt as this argues intelligence as a general ability, not limited to a particular ability
How would we argue that intelligence isn’t “book smarts” and isn’t something that can be taught?
- Intelligence isn’t limited to book learning, academic skills or test-taking smarts
- Intelligence reflects a broader and deeper capability for comprehending our surroundings
Can intelligence be measured?
- Yes
- Measured with intelligence tests
Are there multiple intelligences?
No. There is only a single general variable underpinning intelligence (psychology’s consensus view)
Is intelligence testing a pseudo-science?
No
Francis Galton
- Made the first attempt at creating a standardised test for rating a person’s intelligence
- Created the statistical concept of correlation and was first to apply this to the study of human differences and the inheritance of intelligence
What did Francis Galton hypothesise?
That intelligence should correlate with observable traits such as reflexes, muscle grip, and head size
Define Francis Galton’s ‘eugenics’
- Concerned with “race betterment” and conscious efforts to “improve the race” (State involvement)
- First by encouraging healthy, capable people of above-average intelligence to bear more children (so called ‘positive eugenics’)
- A eugenics office was founded in New York by Davenport - with the aim to “improve the natural, physical, mental, and temperamental qualities of the human family”
- Resulted in policies that targeted least-powerful people (i.e. minority women, immigrants, the physically and mentally ill, and the poor)
Charles Spearman
- Noticed that there were positive correlations between students’ performance in lots of very different subjects
- These correlations went beyond scholastic performance and also correlated with abilities like discriminating weights
- Used Factor Analysis to address the question of “What is underlying these correlations?”
What is a factor analysis (FA)?
- A method of dimension reduction
- Seeks to identify underlying unobservable variables (i.e. latent variables) that are reflected in the observed variables
- You are looking for the simplest structure in your data
- Starting point is a correlation matrix (i.e. the inter-correlations between the observed variables)
- Essentially, looking for variables that correlate highly with a group of other variables but correlate badly with variables outside of that group
Factor Analysis & Intelligence
- Many positive correlations between tasks that possess an element of cognitive difficulty
- A latent factor exists that explains these correlations
- Spearman’s analysis confirmed this
- Latent factor is known as g (or Spearman’s g)
What is a latent variable?
A variable that has been inferred through a mathematical model, as opposed to a variable that has been directly observed
Different names of Spearman’s g
Also known as:
- IQ (intelligence quotient)
- General intelligence
- General cognitive ability
- General mental ability
- g factor (g = general)
Function of Spearman’s g
- Summarises positive correlations among different cognitive tasks
- Reflecting the fact that an individual’s performance at one type of cognitive task tends to be comparable to his or her performance at other kinds of cognitive tasks
- Approx. accounts of 50% of the variance in IQ test performance
Alfred Binet
- “How is intelligence measured?”
- Sought to find an objective way to identify children who needed additional help
- Simon-Binet Intelligence Scale (Mental Age vs Chronical Age)
- Also founded a lab to train teachers for special needs children
Explain how the Simon-Binet Intelligence Scale works
- It gives you a score for a child’s mental age, to then be compared to their chronological age
- The discrepancy between these two ages are what will identify children who would need additional help/resources/teaching
Wechsler Scales: WAIS
- WAIS: Wechsler Adult Intelligence Scale
- A comprehensive measure of adult cognitive ability
Wechsler Scales: WISC
- WISC: Wechsler Intelligence Scale for Children
Wechsler Scales: WPPSI
- WPPSI: Wechsler Preschool and Primary Scale of Intelligence
- Has subtests to determine a child’s variables in performance, IQ and persistent speed
WAIS-III (Wechsler Adult Intelligence Test)
- A modern intelligence test battery
- Holds various different tasks
WAIS-IV (Wechsler Adult Intelligence Test)
- Consists of many, many different tests of abilities to get a comprehensive assessment on someone’s intelligence
- Developed and marketed by the Psychological Corporation
- Every person (2200 ppl; 16-90yo) sat the 15 tests that make up the WAIS-IV
Explain the matrix reasoning subtest of WAIS-IV
- Generally considered the best one to administer (Results produced are closest to your IQ score)
- Mechanism: A picture will be presented -> A piece of the picture is missing -> You need to figure it out
Explain the block design test of WAIS
Using given blocks to make the pattern that is presented
Explain Digit Span (forwards)
- Psychologist reads out a short sequence of digits
- Examinee will be asked to repeat it back in the CORRECT order
- You do this until the examinee starts to make consecutive errors
Explain Digit Span (backwards)
- Psychologist reads out a short sequence of digits
- Examinee will be asked to repeat it back in the OPPOSITE order
- You do this until the examinee starts to make consecutive errors
Explain Letter-Number Sequencing
- Psychologist reads out a sequence of mixed letters and numbers (ex. A 7 B 9 6 C)
- Examinee has to order it as: ascending digits < ascending letters (ex. 6 7 9 A B C)
Explain Coding
- Presented with a key (numbers have a corresponding symbol)
- Put the corresponding symbol in the blank box
- Practice round first and then you get 90 seconds to fill in the test round
- Tests processing speed, memory, physical dexterity
Explain the Vocabulary test
- Asks what different words mean
- Increasing difficulty (ex. chair > presumptuous)
Explain Similarities test
- Finding similarities between different words (ex. a painting and a symphony)
Correlations in WAIS
- Observed substantial correlations between scores on all of the tasks
Standardisation of IQ scores
- Mean of 100
- SD of 15
Three-Level Hierarchy of Mental Ability Test Scores (WAIS-IV)
Level III: g/g factor
- General intelligence
Level II: Cognitive Domains
- Verbal comprehension
- Perceptual reasoning
- Working memory
- Processing speed
Level I: Individual Cognitive Tests
Salthouse (2004)’s Hierarchical Structure of Intelligence
- Cognitive Domains: reasoning, spatial ability, memory, processing speed, vocabulary
- n = 7000 (18-95yo)
- 16 cogn tests; coalesce into five factors/broad domains
- all five factors/domains have high associations with g
General Findings of Intelligence’s Hierarchical Structure: Level 3
- Almost half of the variance seemed to be attributable to a general mental ability that is required to perform all of the tests
- Overarching ability
- Spearman’s g
- General Intelligence
- General Cognitive Ability
- Essentially, it’s the shared variance across sets of intercorrelating cognitive tasks
General Findings of Intelligence’s Hierarchical Structure: Level 2
- There are narrower types of mental ability that relates to the specific type of mental work needed to perform certain types of tests
General Findings of Intelligence’s Hierarchical Structure: Level 1
- In addition to a specific ability to do well on a specific task
Warne & Burningham (2019)
-This paper asks if Spearman’s g is also observed outside of Western contexts as a cross-cultural phenomenon
- Finding: A single factor emerged unambiguously from the majority of the samples
- Used exploratory factor analysis (EFA)
- Results how that g appears in many cultures and is likely a universal phenomenon
Arden & Adam (2016)
- Looked if there was evidence in a large dataset for a hierarchical model of intelligence, if there was an over-aching variable at the top
- The data came from dogs
- Found general intelligence factor in dogs and mammals alike
Moray House Test (1932)
- 73 children aged 11yo took a test, and then resit that same test when they were 77yo
- Perfect stability was not observed but overall pattern was found
- Main finding: People who did well in 1932 (11yo) also tended to do well in 1998 (77yo)
- Correlation was high (>0.6); Concluded that clever children tend to be clever adults
- Supported by the Lothian Birth Cohorts
Are individual differences in intelligence stable across the lifespan?
Yes
Intelligence and Educational Achievement
- 5-year longitudinal study of 7000+ English children
- Examined the association between IQ at age 11yo and GCSE scores in 25 academic subjects at age 16
- Findings: IQ at age 11 was a powerful predictor of educational attainment at age 16 but not the variance in GCSE scores
Is intelligence (IQ related to educational outcomes?
Yes
Is intelligence (IQ related to job success?
Yes
Is intelligence (IQ related to health?
Yes
Intelligence and Job Success
- Assessed how well various factors could predict job performance
- One of which was IQ (psychometric intelligence test)
- Best ones: work sample tests, psychometric intelligence tests, structured employment interview
- Finding: Tests of general intelligence are relevant to job performance (but this is more relevant to more complex professional occupations)
What does emotional intelligence (EI) predict?
- Does not predict job performance more than IQ
- Better social and work relationships
- Being more able to recognise and reason about emotional consequences
Intelligence’s Relationship to Longevity (Health)
- Longitudinal study done on Swedish men going into the army
- Finding: Every SD increase in IQ is associated with 32% decrease in mortality risk 20 years later
IQ and Mental Health
- Lower childhood IQ is associated with an increased risk of Schizophrenia, PTSD< Depression
- An SD increase in youth’s IQ is associated with a risk reduction of 13-43% in the mentioned mental difficulties
- An SD increase in youth’s IQ is associated with a 23-39% reduction in psychological distress (anxiety and milder forms of depression)
Childhood Cognitive Ability and Self-Harm and Suicide in Later Life
- Examined the association between childhood (11yo) cogn ability and self-harm and suicide risk among a Scotland-wide cohort
- Used hospital admission and mortality records to follow individuals from age 34 to 85yo
- Analysis adjusted for childhood and adulthood socioeconomic conditions
- Finding: Higher childhood IQ was significantly associated with reduced risk of self-harm but not for suicide risk
Ball et al. (2024): Childhood Intelligence and Risk of Depression in Later-Life
- Scottish Mental Survey in 1947; Electronic health data records between 1980-2020
- Finding: Higher childhood IQ was associated with a reduced risk of depression in later life
