Powerpoint presentation by Jim Foley

© 2013 Worth Publishers

Chapter 10 Intelligence

Chapter Overview

Definitions of intelligence

One ability or many?

The role of creativity and emotional intelligence

How to construct tests to try to assess intelligence

Intelligence stability, change, and extremes

Genetic vs. environmental influences

Group differences in ability

Racial difference or cultural test bias?

Overall question to consider: does each of us have an inborn level of

talent, a general mental capacity or set of abilities, and can that level be measured and

represented by a score on a test?

Intelligence tests are a series of questions and other exercises which attempt to assess people’s mental abilities in a way that generates a numerical score, so that one person can be compared to another.

Intelligence can be defined as “whatever intelligence tests measure.”

Your college entrance test measures how good you are at scoring well on that test.

“Definition” of Intelligence

Definition of Intelligence: Beyond the Test?

The text defines intelligence,

whether it’s math ability or a rainforest

dweller’s understanding of

plants, as the ability to learn from

experience, solve problems, and use

knowledge to adapt to new situations.

Intelligence: Single or Multiple?

Is intelligence one general ability or several specific abilities?

Charles Spearman general intelligence [g]

Louis Thurstone 7 linked clusters of abilities

Howard Gardner 8 intelligences

Robert Sternberg 3 intelligences

Creativity and intelligence 5 components

Emotional intelligence 4 components

General Intelligence,

also known as g Charles Spearman (1863-1945) performed a factor analysis* of different skills and found that people who did well in one area also did well in another. Spearman speculated that these people had a high “g” (general intelligence).

*Factor analysis refers to a statistical technique that determines how different variables relate to each other; for example whether they form clusters that tend to vary together.

Thurstone’s Seven Clusters of Abilities

Louis Thurstone (1887-1955) disagreed with the idea of one general measure and trait of overall intelligence.

Thurstone found that the results of 56 skill tests fell into 7 clusters.

However, further analysis showed that people who were strong in one cluster tended to be strong in other clusters.

1. Verbal comprehension

2. Inductive reasoning

3. Word fluency

4. Spatial ability

5. Memory

6. Perceptual speed

7. Numerical ability

g

Multiple Intelligences

The “savant syndrome” refers to having isolated “islands” of high ability amidst a sea of below-average cognitive and social functioning.

Howard Gardner’s Multiple Intelligences Howard Gardner (b. 1943) noted that different people

have intelligence/ability in different areas.

Research and factor analysis suggests that there may be a correlation among these intelligences.

Howard Gardner’s Eight Intelligences

Intelligence and Success

10

“Success in life” is impossible to define. However, wealth tends to be related to intelligence test scores, PLUS:

focused daily effort/practice, taking 10 years to achieve success-level expertise.

social support and connections.

hard work and energetic persistence (grit).

Robert Sternberg (b. 1949) proposed that “success” in life is related to three types of ability.

Practical intelligence: expertise and

talent that help to complete the

tasks and manage the complex challenges of everyday life

Sternberg’s Intelligence Triarchy

Analytical intelligence: solving a well-

defined problem with a single

answer Creative intelligence:

generating new ideas to help

adapt to novel situations

Creativity Creativity refers to the ability to produce ideas that are novel and valuable.

[Creative intelligence involves using those ideas to adapt to novel situations.]

Convergent thinking is a left-brain activity involving zeroing in on a single correct answer.

Creativity uses divergent thinking, the ability to generate new ideas, new actions, and multiple options and answers.

Does chess involve creativity?

Robert Sternberg’s Five Components of Creativity

Expertise: possessing a well-developed base of

knowledge

Imaginative thinking: having the ability to see new

perspectives, combinations, and connections

Venturesome personality: tending to seek out new experiences despite risk, ambiguity, and obstacles

Intrinsic motivation: enjoying the pursuit of interests and challenge,

without needing external direction or rewards

Creative environment: having support, feedback, encouragement,

and time and space to think

To Boost Creativity: Four Strategies Pursue an interest until you

develop expertise.

Allow time for incubation (“sleeping on it”) with your attention away from projects, during which unconscious connections can form.

Allow time for mental wandering and aimless daydreaming with no distractions.

Improve mental flexibility by experiencing other cultures and ways of thinking.

Social intelligence refers to the ability to understand and

navigate social situations.

Social and Emotional Intelligence

Emotional intelligence

involves processing and managing the

emotional component of those

social situations, including one’s own

emotions.

•Recognizing emotions in facial expressions, stories, and even in music

Perceiving emotions

•Being able to see blended emotions, and to predict emotional states and changes in self and others

Understanding emotions

•Modulating and expressing emotions in various situations

Managing emotions

•Using emotions as fuel and motivation for creative, adaptive thinking

Using emotions

Components of Emotional Intelligence

Benefits of Emotional Intelligence People with high emotional intelligence often have other beneficial traits, such as the ability to delay gratification while pursuing long-term goals. The level of emotional intelligence, including the skill of reading the emotions of others, correlates with success in career and other social situations.

Intelligence and Brain Anatomy

“Genius” seems to correlate with: overall brain size. the size of some brain

regions such as the parietal lobe.

high brain activity in the frontal and parietal lobes.

extra gray matter (brain cell bodies, seen as more brain surface area/convolutions).

extra white matter (axons) leading to high connectivity among different regions.

•activity of the front part of the frontal lobes to organize and coordinate information

•“being in shape”; using less energy to solve problems than the brains of “normal” people.

Intelligence and Brain Functioning Intelligence in action seems to involve:

Intelligence and Processing Speed

Verbal and general intelligence test scores correlate with the: speed of retrieving information from memory. speed of receiving and processing sensory and

perceptual information.

Q: Did you process the tic tac toe game deeply enough to say whether it was an X or an O in each of the now-empty squares?

Assessing Intelligence

Assessment refers to the activity and the instruments used to measure intelligence.

The challenge is to make these instruments valid (measure what they are supposed to measure) and reliable (yielding the same score if administered again, even if administered by someone else).

to study how (and why) people differ in ability

to match strengths and weaknesses to jobs and school programs

to help the “survival of the fittest” process; trying to select the people who have the greatest abilities. This was the position of eugenicist Francis Galton (1822-1911).

Why Try to Measure Intelligence?

Predicting School Achievement: Alfred Binet

Problem: in the late 1800s, a new law in France required universal education even for those without the ability to succeed with the current instruction.

Solution: Alfred Binet devised tests for children to determine which ones needed help.

Binet hoped to predict a child’s level of success in regular education.

Intelligence: Growing with Age?

Alfred Binet assumed that all children follow the same course of development, some going more quickly, and others more slowly.

Binet’s tests attempted to measure mental age--how far the child had come along on the “normal” developmental pathway.

The implication was that children with lower ability were delayed (with a mental age below their chronological age), and not disabled; with help, they could improve.

Binet Stanford-Binet

William Stern preserved Binet’s comparison of mental to chronological age as: ratio/quotient.

Lewis Terman, of Stanford University, adapted Alfred Binet’s test, adding new test items and extending the age range into adulthood.

Terman also tested many California residents to develop new norms, that is, new information about how people typically performed on the test.

The result was the Stanford-Binet intelligence test.

William Stern’s scoring (1914) of the Stanford-Binet test resulted in the concept of IQ, the Intelligence Quotient.

Binet reported scores as simply one’s mental age; a 10 year old with below average intelligence might have a mental age of 8.

Q: What IQ score do we get for

What do scores mean?

Lewis Terman, of Stanford University, began with a different assumption than Binet; Terman felt that intelligence was unchanging and innate (genetic).

Later, Terman saw how scores can be affected by people’s level of education and their familiarity with the language and culture used in the test.

What to do if you score low on an IQ test?

Binet

Terman

Study, and develop self-discipline and

attention span.

Remove your genes from the

population (eugenics).

IQ

SAT scores (verbal + quantitative)

Aptitude vs. Achievement Achievement tests measure what you already have learned.

Examples include a literacy test, a driver’s license exam, and a final exam in a psychology course.

Aptitude tests attempt to predict your ability to learn new skills.

The SAT, ACT, and GRE are supposed to predict your ability to do well in future academic work.

If the SAT is an aptitude test,

should it correlate with

IQ?

David Wechsler’s Tests: Intelligence PLUS

The Wechsler Adult Intelligence Scale (WAIS) and the Wechsler Intelligence Scale for Children (WISC) measure “g”/IQ and have subscores for:

verbal comprehension.

processing speed.

perceptual organization.

working memory.

In order for intelligence or other psychological tests to generate results that are considered useful, the tests (and their scores) must be:

standardized.

Principles of Test Construction

reliable.

valid.

Many intelligence tests generate a raw score based on the number of answers correct, but can we turn this into a number that tells us how smart/capable a person is compared to the general population?

Standardization

Standardization means defining the meaning of scores based on a comparison with the performance of others who have taken the test before.

William Stern compared our intelligence test score to others by finding a “mental age” of people who scored on average the way we did.

A newer method of generating an intelligence test score is to determine where your raw score falls on a distribution of scores by people of your chronological age.

Standardization: How “Normal” is Your Score?

If we stacked a bunch of Weschler Intelligence Tests (by people your age) in a pile placed by raw score (number of test items correct), there would be a few very high scores and a few low scores, and a big pile in the middle; this bell-shaped pile is called the normal curve. We will call the average raw score “IQ 100.”

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Comparing your score to this standard set of

scores: if you score higher than 50

percent of people, you your IQ is 100.

If your score is higher than 98 percent of the

population, your IQ is around what

number?

Re-Standardization and the Flynn Effect Re-Standardization: Re-testing a sample of the general population to make an updated, accurate comparison group, in case people are smarter than they used to be when the test was first made.

The Flynn Effect:

Performance on intelligence tests has improved over the years, worldwide.

Test your understanding

You took an intelligence test last week and were assigned a number of 120. Then, after decades of the Flynn effect, the test was restandardized this week. Today, you took the same test and got exactly the same number of items correct. Your new intelligence test score is most likely to be:

A. 105

B. 120

C. 128

A test or other measuring tool is reliable when it generates consistent results.

Reliability and Validity

Split-half reliability: do two halves of the test yield the same results?

Test-retest reliability: will the test give the same result if used again?

If your height was measured with a ruler made of stretchy material, what would be the problem?

A test or measure has validity if it accurately measures what it is supposed to measure. Content validity: the test

correlates well with the relevant criterion, trait, or behavior

Predictive validity: the test predicts future performance (e.g. an aptitude test relates to future grades)

If your height was measured with a yardstick on which the units were too small, what would be the problem?

At the higher range of weights and success, weight is less of a valid predictor of success of football linemen.

Predictive Validity: Only

in Broad Ranges

Dynamics of Intelligence

Are intelligence test scores stable or do they change with

age?

Stability of Intelligence during Aging

Cross-sectional studies examine people of different ages all at once.

Older adults do not perform as well as younger adults on intelligence tests.

What factors could explain this?

What is different about these different populations other than their chronological age?

Evidence for stability

Evidence for change/decline

Longitudinal studies track the performance of one group of people, or cohort, over time.

This method yields evidence that intelligence remains stable, or even increases, over time.

What could account for this result?

What are the shortcomings of this method?

Putting the evidence together

Can we combine the information on this chart and form a general impression about whether intelligence declines with age?

Stability of Intelligence during Aging

Which type of intelligence?

Stability of Intelligence during Aging:

Based on this chart, at what age might you do best at completing a crossword puzzle quickly?

Fluid and Crystallized Intelligence

Fluid intelligence refers to the ability to think quickly and abstractly.

Crystallized intelligence refers to accumulated wisdom, knowledge, expertise, and vocabulary .

Stability of Intelligence Test Scores Over the Lifespan

Pushing toddlers to learn does not seem to help much. Only by age four is a child’s performance on intelligence tests a predictor of future performance on intelligence tests.

Based on the results of a longitudinal study depicted in this chart, does intelligence test score at age 11 predict intelligence test score at age 80?

Intelligence and Longevity

In a Scottish longitudinal study, 11-year-olds with higher intelligence test scores lived longer and more independently and were less likely to develop Alzheimer’s Disease.

In a study of nuns , those with lower verbal ability were later more likely to develop Alzheimer’s Disease, which includes a shorter lifespan.

Extremes of Intelligence

The Wechsler Intelligence Scale is set so that about 2 percent of the population is above 130 and about 2 percent of the population is below 70.

Very High Intelligence,

Gifted Intellectual Disability

Extremes of Intelligence

“Intellectual disability” refers to people who have an IQ around 70 or below. have difficulty with adaptive skills, such as:

conceptual skills (literacy and calculation).

social skills, including making safe social choices.

practical daily living skills such as hygiene, occupational skills, and using transportation.

Although some people with high intelligence test scores can seem socially delayed or withdrawn, most are “successful.”

“Gifted” children, like any children, learn best with an appropriate level of challenge.

Segregated, “tracked” programs, however, often unfairly widen achievement gaps.

Genetic and Environmental Influences on Intelligence (Nature and Nurture)

Even if we agree for argument’s sake that “success” in life is caused in part by some kind of intelligence, there is still a debate over the origin of that intelligence.

– Are people “successful” because of inborn talents?

– Or are they “successful” because of their unequal access to better nurture?

Information to tease out the answers can be found in some twin and adoption studies.

Genetic and Environmental Influences on Intelligence

Studies of Twins Raised Apart

Findings from these studies indicate that both nature and nurture affect intelligence test scores.

What explains this difference?

What explains this difference?

Heritability

When you see variation in intelligence between two or more people, the heritability of that trait is the amount of variation that is apparently explained by genetic factors.

This does NOT tell us the proportion that genes contribute to the trait for any one person.

Clarifying Heritability If three people had exactly

the same education, nutrition, and experiences, some psychologists speculate that genes might be responsible for perhaps 40 percent of their intelligence; nurture certainly made a big impact.

However, such identical nurturing (which is actually impossible) could not create differences in intelligence.

With identical nurture, the heritability of intelligence would be virtually 100 percent.

Genetic Influences on Intelligence

Identical twins seem to show similarity in specific talents such as music, math and sports.

The brains of twins show similar structure and functioning.

There are specific genes which may have a small influence on ability.

Adoption Studies

With age, the intelligence test scores of adoptees looks more and more like that of their ____________ parents.

In another study, heritability of intelligence test scores continued to increase beyond age 16.

(adoptive? birth/biological?)

Environmental Influences on Intelligence

Environment has more influence on intelligence under extreme conditions such as abuse, neglect, or extreme poverty.

Tutored human enrichment has a larger impact on compensating for deprivation than on boosting intelligence under normal conditions.

Schooling and Intelligence

Preschool and elementary school clearly have at least a temporary impact on intelligence test scores.

College can have a positive impact on intelligence test scores if students have: – motivation and incentives. – belief that people can

improve. – study skills, especially the

willingness to practice.

Understanding Group Differences in Test Scores

Now, let’s look at:

gender differences.

“racial” differences.

understanding the impact of environment.

within-group differences and between-group differences.

the impact of test bias and stereotype threat on performance.

Supposed Male-Female Ability Differences

Male/female difference related to overall intelligence test score.

Boys are more likely than girls to be at the high or low end of the intelligence test score spectrum.

Girls tend to be better at spelling, locating objects, and detecting emotions.

Girls tend to be more verbally fluent, and more sensitive to touch, taste, and color.

Boys tend to be better at handling spatial reasoning and complex math problems.

It is a myth that boys generally do better in math than girls. Girls do at least as well as boys in overall math performance and especially in math computation.

Male-Female Ability Differences

Standard

Tests of Male and Female Strengths

Ethnic/Racial Differences in Intelligence Test Scores

The green triangle shows African-Americans scoring higher than the average non-African-Americans. How can we interpret this group difference in average intelligence test scores? We will look at the issue of test bias and other factors affecting scores for perceived minorities.

The bell curve for African American intelligence test scores is centered at 85. For non-African Americans, the average is 100.

Whatever the cause of this score difference, it is incorrect to use this information to predict the score of an individual.

But first…

Understanding Group Differences: Within-group vs. Between-group Group differences, including intelligence test score differences between so-called “racial groups,” can be caused by environmental factors. Below: the difference between groups is caused by poor soil (environment).

The “Racial” Intelligence Test Score Gap

Racial categories are not distinct genetically and are unscientific.

Both “whites” and “blacks” have higher intelligence test scores than “whites” of the 1930s.

“Whites” may have more access to “fertile soil” for developing their potential, such as:

schools and educational opportunities.

wealth, nutrition, support, and educated mentors.

relative freedom from discrimination.

Two Problems Called “Bias”

Are Tests Biased?

Bias 1: In the popular sense of the word, intelligence tests are often biased. Often, tests have questions which rely on knowledge of mainstream culture. For example, the 2011 SAT writing prompt demanded students discuss the authenticity of reality television shows.

Bias 2: Aptitude tests seem to predict future achievement equally well for various ethnic groups, and for men and women.

Test makers must prevent “bias” in the popular sense of the word: making it easier for one group than another to score high on a test. Test makers also strive to prevent the scientific form of bias: making it easier for one group than for another to have their abilities accurately assessed, and their future performance predicted.

The Effect of Stereotype Threat

Study result: Women did worse on math tests than men, except when they are told first that women usually do as well as men on the test. Why?

Study result: Blacks/African-Americans did worse on intelligence tests when reminded of their racial/ethnic identification right before the test. Why?

Study result: Blacks/African-Americans scored higher when tested by Blacks rather than being tested by Whites. Why?

The Power of Expectations

Stereotype threat refers to a feeling that one will be evaluated based on a negative stereotype.

Stereotype threat may interfere with performance by making people use their working memory for worrying instead of thinking.

This worry is self-confirming/fulfilling: the effect of minority status on performance is worsened by worry about that effect.

Is discriminating among college or job applicants based on test scores better than discriminating based on appearance?

Can test scores be used as Alfred Binet suggested: to identify those who would benefit from educational interventions?

Can a person’s worth and potential be summed up in one intelligence test score?

Issues Related to Intelligence Tests