ch.9 intelligence testing

can intelligence be specifically defined?

• no intelligence cannot be specifically defined

  • this is because people show different KINDS of smarts.

    • intelligence is not solely based on one thing

does how well you do in school define problem-solving in all settings?

No, school success doesn't always reflect real-world problem solving

Is the judgement of intelligence biased?

Yes it is often biased by confidence and social skills

Galton's Idea of intelligence

• Intelligence = strong sensory abilities

  • people with better vision, hearing, touch → learn more about the world

what was the issue with Galton's idea of intelligence

Sensory abilities didn't correlate with each other

• e.g. great eyesight does not = great hearing

  • sensory scores also did now predict school grades

Binet's idea of intelligence

• Intelligence = complex thinking (memory, attention, reasoning)

  • this was to help identify studens needing extra educational support

    • to test this there were 30 tasks in increasion difficulty

mental age score

• a child's score is compared to the average of their age

  • Mental age less than chronological age → may need additional support

  • Mental age greater than chronological age → advanced abilities

the stanford-binet (U.S. version)

• introduced the IQ formula → IQ = (Mental Age/Chronological age) x 100

why did the Stanford-Binet test not work?

• the original formula did not work for adults

Deviation IQ

A score compared to the average for your age group

• Average IQ = 100

  • e.g. 115 = above average

Wechsler Adult Intelligence Scale (WAIS) measures..

Measures full scale IQ (overall ability)

What does Full Scale IQ consist of?

1. General Ability Index

2. Cognitive Profieciency Index

What does General Ability Index measure?

Measures:

• Verbal Comprohension & Perceptual Reasoning

  • reasioning & understanding without focusing on speed/time constraints or working memory

    • CORE REASONING ABILITY

What does Cognitive Proficiency Index measure?

Measures:

• Working memory & Processing speed

  • reflects mental efficiency → how quickly and accurately you can think (e.g. paper and pencil tasks)

Examples of GAI tests

• Verbal Comprehension index

  • similarities, vocabulary, information

• Perceptual reasoning index

  • block design, matrix reasoning, visual puzzles

Examples of CPI tests

• Working memory index

  • digit span, arithmetic

• Perceptual speed index

  • symbol search, coding

Raven's Progressive Matrices

created to eliminate the biases with Tradition IQ tests

• uses pictures instead of words → minimizes the language and cultural demands

  • was made to be more accesible across cultures, social classes, and education levels

What does the Raven's Progessive Matrices measure?

• ability to detect patterns in shapes & designs

  • e.g. choose the piece that completes the matric

    • taps into fluid reasoning → problem solving is independent of prior knowledge

What did traditional IQ tests favour?

• Native english speakers

• people familiar w/ western culture

IQ tests in WWI

• Military intelligence tests

  • used to identify who should become officers vs. non-officers

    • was a way to make selection more “objective" and efficient

Post War IQ tests

• IQ tests were implemented into schools

  • used to sort students into:

    • Academic paths (university bound) → high scores

    • Vocational tracks (skilled trades/workforce) → lower scores

What was the issue with the IQ testing in the past?

• the tests were treated as fully objective and unbiased

  • however the approach just reinforced the existing inequalities

  • this set the stage for serious misuse(s) of intelligence testing

Eugenics Movement

• People took Darwins theory of evolution and applied it to IQ (Social Darwinism)

  • This caused the movement to “improve" society through controlling reproduction

    • Darwin's cousion argued that success ran in families due to heredity

      • this ignored social factors (e.g. wealth, privilege, access to education, etc.)

What did the Eugenics movement cause?

This causes early IQ tests to be used to justify the eugenics policies and claims of racial superiority

• this led to harmful practices

  • e.g. forced sterilizatio

How did colonialism shaped testing?

• Intelligence testing developed alongside Western colonial expansio & evolutionary theory

  • these ideas were misused to claim Western (especially White) superiority

    • This caused Non-Western & racialied groups to be judged against biased standards

How did IQ tests reinforced inequality

• Earlier tests favoured White, Western, English-Speaking populations

  • This resulted in lower scores from Indigenous, Black & other marginalized groups were misinterpreted as “racial deficiency"

    • The IQ results were used to justify segregation & restrictive social

What real-world harm was caused by Eugenics?

• Eugenic laws led to forced sterilizations in 30 U.S.S states & 2 Canadian provinces

  • This disproportionately targeted Indigenous Peoples, Black communities, new immigrants & poor families

    • Sterilizations made woman unable to have children

Why is the Eugenics topic complicated?

• The early IQ tests showed consistent score differences across racial groups

  • These findings were often used to support Eugenics, discrimination & racist policies

    • Racial categories are not biologically distinct, making group comparisons scientifically problematic

What did the Eugenics data sow?

• IQ gaps appeared even on more “ cultured-reduced" tests

  • however the scores do NOT reflect genetic differences in intelligence

  • no racial group is genetically “superior"

    • IQ tests reflect language, culture, opportunity, education, & systemic inequities

What is the modern debate with IQ tests?

• The Bell Curve reignited controversy by claiming IQ predicts life outcomes & social class

  • Critics Argue:

    • The methods were flawed

    • The conclusions ignored structual inequalities

    • Meritocracy is impossible when systems advantage some groups over others

What are the problems with Racial Superiority Interpretation?

1. Cultural bias in testing

2. Testing process bias

3. Stereotype threat

4. Environmental inequities

5. Beliefs about intelligence

Cultural bias in testing

• Early & modern IQ tests often reflect Western language & cultural norms

• Even “cultured-reduced" tests don't eliminate group score differences

Testing process bias

• Test performance affected by:

  • Familiarity w/ testing

  • Comfort w/ testing environment

  • Motivation & rapport w/ examiner

Stereotype threat

• Awareness of negative stereotypes can lower performance

• Increases anxiety + shifts attention away from the task

Environmental inequalities

• Group differences often reflect unequal life conditions, not genetics:

  • Poverty, stress, underfund school, etc.

  • Limited healthcare access

  • Exposure to toxins (e.g. lead)

  • Poor nutrition & chronic illness

Beliefs about intelligence

• Experiences w/ discrimination or academic struggle can create a belief that intelligence is fixed

• These beliefs reduce motivation to improve but research shows intelligence can grow w/ the right supports

Entity Theory

Intelligence is fixed; you wither have it, or you don't

Incremental theory

Intelligence can grow w/ effort, strategies & practice

Fixed mindset

→ avoids challenges, gives up after setbacks

Growth mindset

→ persists, learns from mistakes, builds resilience

Why do mindsets matter?

Students and peoples beliefs strongly shape motivation, performance & confidence

What do Savant abilities show us?

• Savants (people who have exceptional aptitude in one particular field, but suffer from different diabilities) may have severe limitations in some areas and extraordinary abilities in others

  • challenges the idea that intelligence is one single “general ability"

    • this raises key questions: is intelligence one thing or many, how do abilities relate across domains, what does it really mean to be “smart"

general ability (g)

a broad mental strength that supports learning, reasoning, and problem-solving across domains

• other words: overall ability to learn, reason, and solve problems

  • higher g = more efficient brain processing

why is g important?

1. School performance

2. Quick thinking & self-control

3. Health

4. Job Success

5. Income

6. Lifespan

What does g show?

• People who do well on one type of mental taks often do well on others

  • it relates to real-world outcomes like school and job performance

What limits do g have?

• Correlation does not = causation

  • other factors also matter

• g shows PATTERNS, not how intelligence actually works

  • a single score can't explain uneven abilities

    • e.g. savants

What does g show us?

• People can be strong in one area and weak in another

  • intelligence may have many forms, not just one number

Intelligence has 2 parts

1. g - general ability

2. s - specific skills for particular tasks

Thurstone's view of intelligence

That intelligence is made of several separate abilities, not one big factor

• this identified 7 key abilities

  • e.g. verbal, numerical, spatial, memory

Three levels of Intelligence

1. Specific abilities

2. Middle-level abilities

3. General Intelligence

Specific Abilities

Skills for particular tasks

Middle-level abilities

clusters like verbal, spatial, memory

General intelligence

broad overall ability

Hierarchical Model of Intelligence

Combines spearman's g and Thurstone's multiple abilities

• explains why people can have:

  • A strong general ability and unique strengths and weaknesses on specific tasks

two types of g

1. Fluid intelligence

2. Crystallized intelligence

Fluid intelligence

• One's ability to figure things out

  • the blending on multiple cognitive abilities

    • e.g. switching & sustaining attention, etc.

  • solving new problems, reasoning, pattern recognition, etc.

Crystallized intelligence

• One's ability to know things

  • e.g. vocabulary, facts, general knowledge

• Build from experience

• Stays stable longer into adulthood

How do fluid intelligence and crystallized intelligence relate

• Fluid intelligence may help build crystallized intelligence over time

  • Learning → knowledge

• Hard to measure fluid intelligence w/o tapping some prior knowledge (crystallized intelligence)

• Both rely on different brain systems

why does the fluid and crystallized intelligene relationship matter?

• shows intelligence is not just one thing

• helps explain age related changes

• leads to better, more precise cognitive testing

why was the g model challenged?

• not everyone fits a single “general intelligence” model

• savant abilities, brain injuries, & everyday talen differences show unever strengths

• gardener argued intelligence is not one ability, but many

The 9 independent intelligences

1. Linguistic

2. Logical-mathematical

3. Spatial

4. Bodily-kinesthetic

5. musical

6. interpersonal

7. intrapersonal

8. naturalistic

9. existential

can fluid intelligence compensate for low crystallized intelligence?

sometimes it can!

• fluid intelligence = reasoning, problim-solving, identifying patterns

  • strong fuild intelligence can help figure things out on the spot

    • only useful when tasks are new, abstract, or don't require prior knowledge

BUT NOT ALWAYS

• it cannot account for vocabulary, facts, and learned knowledge

  • it cannot replace it when tasks rely on:

    • backqround knowledge, reading comprehension, and subject-subject information

what character from a show, shows high fluid intelligence

Frank Gallagher from shamless

• he lacks responsibility, stability, & long-term planning

  • however consistently demonstrated strong fluid intelligence in solving novel problems, thinking on his feet, and adapting quickly in unprdictable situations

what did frank gallagher's high fluid intelligence show?

1. Quick, creative problem-solving

2. pattern recognition in social systems

3. rapid adaptation to new environments

4. cognitive agility in persuasion & manipulation

what is CTE?

It is a progressive, degenerative brain disease caused by repeated head impacts and concussions

where is CTE a big problem?

In high impact sports

• The NHL, NFL, Boxing, etc.

What is CTE linked to?

CTE is linked to memory loss, mood problems, dementia and suicidality

why are cognitive tests important in high impact sports?

To make sure they have a baseline before CTE happens.

• They take a test before which gives a baseline on how they cognitively performed before CTE occured.

  • A test is taken especially when a player gets a head injury, which helps determine when it's safe to return to play

    • They take these tests annually

why are females more susceptible to concussions?

1. Neck Strength: On average, females have less neck strangth/stability → more accerleration on impact

2. Hormonal factors: Estrogen may influence brain vulnerability

3. Reporting differences: Females tend to report symptoms more consistently

4. Biomechanics: Differences in head mass and neck-body ratio

is there a difference in intelligence between men and women?

No, males and females have the same average IQ

• Early studies that show difference were likely due to test bias.

What kinds of test biases were there?

• Males tests showed greater score variability

  • There were more males at both very low and very high IQ levels

    • But really it does not mean males are innately more intelligent

What are the cognitive differences of men and women?

FEMALES tend to perform better on:

• Verbal tasks

• Some memory tasks

• Reading basic emotions

MALES tend to perform better on:

• Visuopatial tasks (e.g. mental rotation, aiming)

  • depth perception

What other influences cause the differences between both genders?

• stereotypes discouraging girls from math/science

• biased expectations from parents and teachers

• structual barriers in education and workplace environments

Why is intellectual disability more common in males?

1. Genetics

2. Development vulnerability

3. Epidemiological patterns

Genetics

Males inherit X linked conditions

• many causes of IDD are linked to the X chromosome

  • Males only have X, which means they are more vulnerable to harmful mutations

    • e.g. Fragile X syndrome

Developmental vulnerability

Male infants show higher risk for:

• Prenatal complications

• Birth injuries

• Certain metabolic disorders

Epidemiological patterns

• Studies consistently find more males than females diagnosed (about 1.3-1.5 to 1)

• Sex difference increases with more severe forms of IDD

what shapes intelligence?

1. Biology (Nature) - brain structure, genetics, neural efficiency

2. Environment (Nuture) - Education, nutrition, stress, social support

3. Behaviour - study habits, sleep, practice, mindset

what did Einsteins brain show?

• Extra folds in frontal and parietal lobes

• Higher glial-to-neuron ratios

• Greater surface area in areas linked to math & abstract thinking

Is intellgence fixed? If not how can it change?

Intelligence isn't fixed

• Cognitive abilities can improve through:

  • Practice & effort

  • Enriched environments

  • Effective learning strategies

  • Growth mindset

Why do we study families in relation to intelligence?

• Helps reveal how much genes vs. environment influence intelligence

• Twin adoption studies provide the strongest evidence

What did they find when they studied intelligence in relation to families/twins/genetics

• More genetice similarity = more similar IQ scores

  • Siblings < Fraternal Twins < Identical twins

• Identical twins raised together have high IQ correlation than those raised apart

what does this show about genetics and intelligence?

• Genetics play a major role in intelligence

  • BUT environment still matters

• Genes set potentials

• Experiences shape outcomes

what is the percentage of heritability of intelligence?

40-80%

• genes DO NOT determine 40-80% of someone's intelligence

Heritability of intelligence in wealthy, stable environments

• It is higher (~72%)

  • Fewer environmental differences

    • genes explain more variation

Heritibility of intelligence in poverty or unstable environments

• It is lower (~10%)

  • Many environmental factors shape intelligence

why does environment matter?

• noise, stress, nutrition, schooling, & community resources all influence development

• different environment activate genes in different ways (genes x environment interation)

  • Genes matter but so do opportunities, resources, & lived experiences

what is behavioural genomics?

A field that studies how specific genes interact w/ the environment to shape behaviour

• helps iddentify genes and brain systems linked to learning, memory & problem-solving

Knockout studies

• removing a gene to see it's effect

  • some KO mice showed impaired learning

Transgenic studies

inserting a gene to boost cognitive function

• e.g. doogie mice w/ enhance NMDA receptors learn faster & remember better

does a bigger brain mean higher IQ?

No, it's a common assumption but it is not fully supported

What brain features matter more than size?

• Folds (gyri) → more surface area & connectivity

• White matter connections → faster, more efficient communication

• Strong networks between frontal & parietal lobes

What does IQ really measure?

It measures many processes

how do genes and environment affect intelligence?

genes only affect it when the env't allows them to

• Brain regions linked to intelligence are highly responsive to experienc

  • e.g. Enriched environments = faster learning & stronger brain development

    • therefore.. Stimulating, supporting environments promote cognitive growth

      • Deprived environments can limit brain development & learning

what does research show about birth order in relation to intelligence?

• Large studies find that first-born children score ~3 IQ points higher than second-born

  • additionally ~4 points higher than third-born

    • though these differences are small and not absolute

why might first-born children have slightly higher IQ scores?

First borns are able to receive more:

• One-on-one parent interaction early in life

  • parents are motivated or attentive

    • Afterwads older siblings will tend to teach the younger siblings, which only deepens their learning too

Socioeconmic Status (SES)

a measure of an individuals or family's relative position in society based on a combination of income, educational attainment, and occupational prestige.

Why does SES matter?

Intelligence (IQ scores) strongly correlate w/ socioeconomic status

• Higher SES = more opportunities

• Lower SES = less opportunities

High SES Homes

These offer more enrichment

• books, technology, educational outings

  • supportive parenting, less punitiv discipline

Low SES homes

these often face barriers

• limitied resources, higher stress, less access to educational opportunities.