Chapter 10Intelligence

DEFINING INTELLIGENCEExactly what makes up

intelligence is a matter of debate

David Wechsler’s Definition Act purposefully Think rationally Deal effectively with the

environment

EARLY THEORIES OF INTELLIGENCE Charles Spearman

Believed intelligence is general – “G-Factor”

People who are bright in one area are usually bright in other areas as well

L. L. Thurstone Believed that intelligence is

made up of seven distinct, independent abilities: Spatial ability, perceptual speed, numerical ability, verbal meaning, memory, word fluency, reasoning

Thurstone did not believe in a G-Factor, but researchers who scored well in one of the seven areas tended to score well on others.

Ain’t nuthin but a G thang.

7 Differen

t abilities!

Early Theories of Intelligence:

R. B. Cattell Identified two clusters of mental abilities Crystallized intelligence

includes abilities such as reasoning and verbal skills

Fluid intelligence includes skills such as spatial and visual imagery, rote memory, and the ability to notice visual details

While education can increase crystallized intelligence, it was not thought to have any effect on fluid intelligence

Contemporary Theories of Intelligence:Howard Gardner

Logical-mathematical

Linguistic Spatial Musical

Bodily-kinesthetic

Interpersonal Intrapersonal Naturalistic

Howard Gardner’s theory of multiple intelligences

Explains savant syndrome

CONTEMPORARY THEORIES OF INTELLIGENCE:HOWARD GARDNER

CONTEMPORARY THEORIES OF INTELLIGENCE:ROBERT STERNBERG

Triarchic theory of intelligence claims there are three types of intelligence (prototype of 3 grad school applicants) Analytical intelligence includes

the ability to learn how to do things, solve problems, and acquire new knowledge (Alice)

Creative intelligence includes the ability adjust to new tasks, generate novel ideas, use new concepts, and respond well in new situations (Barbara)

Practical intelligence includes the ability to select contexts in which you can excel and solve practical problems (Celia)

CreativityDefined as the ability to

produce novel and socially valued ideas or objects

Creativity and Intelligence – Early studies suggested that there was little relationship between the two, however, later research indicates otherwise: creative individuals tend to have higher IQs AND creative individuals are perceived as being more intelligent as well.

IQ of at least 120 required to be creative, but it doesn’t mean you will be!

Convicted murderer Phil Spector was seen as a creative genius in his heyday. Creativity and evil, however, often go hand in hand (as does large hair).

Creativity Creativity Tests –

Open-ended questions; scoring is based upon the number and originality of a person’s answers Torrance Test – Individuals create and

explain a picture, its origins, and consequences from incomplete images

Mednick’s Remote Association Test (RAT) – given three words – you come up with a fourth word that the other three can be combined with e.g. hand, lone, win (answer = some)

Sternberg’s Components of creativity Expertise Imaginative thinking skills A venturesome personality Intrinsic motivation A creative environment

Contemporary Theories of Intelligence Daniel Goleman

Proposed theory of emotional intelligence

Emotional intelligence has five components Knowing one’s own

emotions Managing one’s own

emotions Using emotions to

motivate oneself Recognizing the emotions

of other people Managing relationships

Does emotional intelligence go too far?

Comparing Contemporary Theories

Gardner’s Multiple Intelligences

Sternberg’s Triarchic Intelligences

Goleman’s Emotional Intelligence

Logical-Mathematical

Linguistic

Analytical

Spatial

Musical

Body-Kinesthetic

Creative

Interpersonal Practical Recognizing emotions in others and managing relationships

Intrapersonal Knowing, managing, and motivating yourself with emotions

Can Intelligence Be Neurologically Measured?

Brain size seems to be modestly correlated with intelligence, but this is not always the case.

Specific brain areas such as frontal and parietal lobes seem to be important regions

The varying sizes of brain structure could result from nature and/or nurture

Perceptual speed tends to indicate intelligence

Neurological speed also tends to indicate intelligence

Lord Byron was not only emo, beautiful and

brilliant, but his brain was massive to boot!

INTELLIGENCE TESTS: BINET AND SIMON

First test of intelligence, developed to identify children who might have difficulty in school

Binet developed the concept of mental age in children

Mental Age = age at which you perform intellectually - may or may not correspond with chronological age

Goal was to use intelligence tests to improve children’s educational experience – not limit their opportunities with harmful labels.

INTELLIGENCE TESTS:STANFORD-BINET INTELLIGENCE SCALE

Lewis M. Terman’s adaptation of the Binet-Simon scale

Terman’s goal was to measure “inherited intelligence” for purpose of eugenics

The test was used on immigrants and army recruits Results interpreted as justifying superiority

of Anglo-Saxon people Used to justify limits set on immigrants from

southern and eastern Europe - 1924 Stanford-Binet measures four kinds of

mental abilities Verbal reasoning Abstract/visual reasoning Quantitative reasoning Short-term memory

INTELLIGENCE TESTS:STANFORD-BINET INTELLIGENCE SCALE

Terman’s work served as the basis for William Stern of Germany to develop the concept of IQ, or Intelligence Quotient

IQ = Mental Age/Chronological Age x 100 Most common IQ score? Problem of IQ calculation beyond

adulthood solved through comparison with norms for every age group

Sample Problems: Mental Age = 8, Chronological age =

6, IQ = ? IQ = 150, Chronological age = 4.

Mental age = ?

EUGENICS MOVEMENT:POLITICIZED “SCIENCE”

INTELLIGENCE TESTS:WESCHLER SCALES

The Wechsler Adult Intelligence Scale (WAIS) is the most commonly used test of intelligence for adults

WAIS is divided into to 11 parts that focus on verbal abilities and on performance skills

Also a version for children, Wechsler Intelligence Scale for Children (WISC)

INTELLIGENCE TESTS:WESCHLER SCALES

APTITUDE VS. ACHIEVEMENT? Achievement tests measure what you have

already learned Aptitude tests measure your potential to learn.

There is a positive correlation between aptitude tests results and intelligence tests.

e.g. correlation between SAT and IQ?

PRINCIPLES OF TEST CONSTRUCTION All good intelligence must be all three of the

following: Standardized Reliable Valid

Standardization - uniform rules for administering, taking and scoring the test based on comparing performance to that of a pretested group. Norms – performance benchmarks established

during test development used to establish “average” performance.

Representative Sample – group used to establish norms that adequately reflects the demographics of those who will be taking the test.

Standardization Sample – the group that determined the norms

PRINCIPLES OF TEST CONSTRUCTION In a standardized intelligence test, scores should

be distributed in a bell-shaped curve, or normal curve.

Most individuals taking intelligence tests should score a 100, with the majority falling between 85-115.

Due to the Flynn Effect, intelligence tests must be periodically restandardized to keep norms valid.

PRINCIPLES OF TEST CONSTRUCTION Reliability - Ability of a test to provide

consistent and stable scores Test-retest reliability – a method of

measuring reliability where the same individual is given the test on two different occasions and scores are compared. Similarity in scores indicates good test-retest reliability

Split-half reliability – method of measuring reliability where the individual takes one test that is divided in half. Performance on each half is compared for similarity.

Alternate-form reliability – two different but similar forms of the test are given on separate occasions and scores are compared for similarity.

PRINCIPLES OF TEST CONSTRUCTIONValidity - Ability of a test to measure

what it purports to measure Content validity – tests ability to cover the

complete range of material (content) it is supposed to measure

Predictive validity – how well a test score predicts an individual’s performance in the future Correlation between SAT scores and first-year

grades in college? +.5 – not great! Correlation between GRE and grad school

grades? +.4 – even worse!

Scoring the IQ TestRaw Score - number of questions

answered correctly; doesn’t tell much about performance

Standard Score - score that tells you how you did compared to other test takers – a much better read of performance

Percentile Score - what percentage of test takers you scored better than

What does it mean to score in the 85th percentile?

INTELLIGENCE:STABILITY OR CHANGE?

Intellectual ability does not seem to stabilize until age 7, but by age 4 performance on intelligence tests seems to predict future performance

Ian Deary study seems to establish that intelligence does remain relatively stable over time. All 10.5-11.5 year-olds in Scotland tested in 1932 Follow up on the survivors done as recently as

2004 indicates intelligence tests remained consistent

Extremes of Intelligence: Giftedness

Definition top 3% of IQ scores,

typically over 132 Superior IQ combined with

ability in academics, creativity, and leadership

Giftedness is often in specific areas

“Globally” gifted people are rare

Some gifted children feel isolated and lonely, but most are well adjusted

Specialized Programs of Study?

EXTREMES OF INTELLIGENCE: MENTAL RETARDATION (INTELLECTUAL DISABILITY) Definition

IQ < 70; lowest 3% of IQ scores not a result of accident onset before age 18 substantial limitations in functioning

Causes – drug abuse during pregnancy, genetic disorders such as Down Syndrome, lack of fetal nutrition

Levels Mild - 90% of cases Moderate - 6% of cases Severe - 3% of cases Profound - 1% of cases

Some people with retardation show savant performance on particular skills

EXTREMES OF INTELLIGENCE: MENTAL RETARDATION (INTELLECTUAL DISBAILITY)

Education and the LawAll children are entitled to an education that

is… FREE PUBLIC APPROPRIATE

Mainstreaming keeping special needs kids in regular ed classes for

whatever subject areas/activities they can handle Inclusion

rather than taking special needs kids out of regular ed classes for support, bring support personnel into regular ed classes so kids can stay with their peers.

Leveling separating children by ability into different classes

Criticisms of IQ TestsTest content and scores

Critics argue that IQ test measure a narrow set of skills

Some feel that the tests merely measure test taking ability

Tests may discriminate against minoritiesUse of intelligence tests

Could result in permanent labeling IQ and success

Relationship does exist, but may be the result of a self-fulfilling prophecy

Case of Gladys Burr?

WHAT DETERMINES INTELLIGENCE?NATURE

Biological similarities in Adoption Studies IQ scores of child more closely correlated with

biological mother than adoptive mother.

Identical Twins reared apart after identical twins reared together, identical twins

reared apart have the highest correlation of IQ scores.

Tryon’s Rats nature…AND NURTURE…

Correlation of IQ Scores of Family Members

WHAT DETERMINES INTELLIGENCE?NURTURE

Isolated or Deprived Environments individuals living in culturally or

physically impoverished environments have lower IQ scores

Adoption Studies and Improved Environment children demonstrated elevated IQ

scores after being moved from crowded orphanage to distributing them into less crowded adult wards

H.M. Skeels orphanange study Capron and Duyme’s adoption study

high vs. low SES

WHAT DETERMINES INTELLIGENCE?:FAMILY SIZE AND STRUCTURE Belmont and Marolla (1973) Zajonc and Markus (1975) Intellectual Climate – numerical calculation of the level

of intellect in a household, based on the number of family members and their ages. Example Calculation – adults = 30, teens = 15, children = 5, and newborns = 0: 2 adults:

30+30=60/2=intellectual climate of 30 2 adults and a newborn:

30+30+0=60/3=intellectual climate of 20 Intellectual climate goes down most when there are

many children born in rapid succession.

Heredity vs. Environment:Which is More Important? There is general agreement that both

heredity and environment affect IQ scores Debate centers around the relative

contribution of nature (heredity) and nurture (environment) to the development of intelligence

DETERMINANTS OF INTELLIGENCE: SEX

Early Research (1970s) males excel at math/spatial skill while females excel at verbal

Hyde and Linn’s Meta-analysis (1988) intellectual differences between males and females are so small

that they are not statistically significant. Today’s Conclusions

Overall, men and women do not differ significantly in general intelligence

Women show slight advantage in verbal and mathematical computation skills while men show an advantage in spatial ability

Men are more likely to fall in the extremes of intelligence range There is no explanation for why these minimal differences exist –

are they cultural or inborn?

DETERMINANTS OF INTELLIGENCE:CULTURE

Culture Difference in academic

performance between American and Asian students are found from first grade through high school in mathematics and reading

May be related to a difference in cultural attitudes toward ability and effort

Stability of Intelligence IQ stays relatively steady

over course of life