What is Intelligence?

LOQ: How do psychologists define intelligence, and what are the arguments for g?

Intelligence has been defined as whatever intelligence tests measure (typically school smarts)

• intelligence is not a quality like height or weight, which has the same meaning to everyone worldwide.

  • People assign this term to the qualities that enable success in their own time and culture

    • In Cameroon, intelligence might be understanding the medicinal qualities of local plants

    • In a North American high school, it might be mastering difficult concepts in calculus or chemistry

    • Both of these places define intelligence as the ability to learn from experience, solve problems, and use knowledge to adapt to new situations.

Intelligence: the ability to learn from experience, solve problems, and use knowledge to adapt to new situations.

Is Intelligence One General Ability?

Charles Spearman believed we have one general intelligence (often shortened to g)

• This is at the e heart of all our intelligent behavior

• He granted that people often have special, outstanding abilitie

  • noted that those who score high in one area, such as verbal intelligence, typically score higher than average in other areas, such as spatial or reasoning ability

• His beliefs come from his work with factor analysis

  • a statistical procedure that identifies clusters of related items.

General Intelligence (g): according to Spearman and others, underlies all mental abilities and is therefore measured by every task on an intelligence test

Theories of Multiple Intelligences

LOQ: How do Gardner’s and Sternberg’s theories of multiple intelligences differ, and what criticisms have they faced?

Gardner’s Multiple Intelligences

Howard Gardner identified 8 relatively independent intelligence, including the verbal and mathematical aptitudes assessed by standardized tests

• also proposed a ninth possible intelligence—existential intelligence—the ability “to ponder large questions about life, death, existence.

• Viewed these e intelligence domains as multiple abilities that come in a different package

  • People with savant syndrome often score low on intelligence tests and may have limited or no language ability but have a lot of brilliance

4 in 5 people with savant syndrome are male

• Many also have autism spectrum disorder (ASD)

Savant Syndrome: a condition in which a person otherwise limited in mental ability has an exceptional specific skill, such as in computation or drawing.

Sternberg’s Three Intelligences

Robert Sternberg agreed with Gardner that there is more to success than traditional intelligence and that we have multiple intelligences

• Sternberg proposed a triarchic theory, proposing 3 intelligences

  • Analytical (academic problem-solving) intelligence is assessed by intelligence tests, which present well-defined problems having a single right answer.

  • Creative intelligence is demonstrated in innovative smarts: the ability to adapt to new situations and generate novel ideas

  • Practical intelligence is required for everyday tasks that may be poorly defined and may have multiple solutions

• Both agree that Multiple abilities can contribute to life success as well as different varieties of giftedness bring challenges and benefits for education

Criticisms of Multiple Intelligence Theories

Using factor analysis confirms that there is a general intelligence factor: g matters

• predicts performance on various complex tasks and in various jobs

Success is not built on one ingredient

• It is a combination of talent and grit

  • People who become highly successful tend also to be conscientious, well-connected, and doggedly energetic

  • K. Anders Ericsson as well as others say that a 10-year rule is a common ingredient to become an expert in various things such as chess, music, dance, etc.

    • 10 years of intense, daily training

  • Sucess= gift of nature + a lot of nurture

Emotional Intelligence

LOQ: What are the four components of emotional intelligence?

Psychologists have explored our social intelligence- understanding social situations and managing ourselves successfully

• Edward Thorndike proposed an idea saying, “the best mechanic in a factory may fail as a foreman for lack of social intelligence

• Emotional intelligence is a critical part of social intelligence

There are four abilities in emotional intelligence

• Perceiving emotions (recognizing them in faces, music, and stories)

• Understanding emotions (predicting them and how they may change and blend)

• Managing emotions (knowing how to express them in varied situations)

• Using emotions to enable adaptive or creative thinking

Emotionally intelligent people are both socially aware and self-aware

• Overwhelming emotions such as anxiety or anger to not overtake them

• can read others’ emotional cues

  • know what to say to soothe a grieving friend, encourage a workmate, and manage a conflict.

• delay gratification in pursuit of long-range rewards

• more often succeed in relationships, career, and parenting situations than academically smarter but less emotionally intelligent people

Gardner includes interpersonal and intrapersonal intelligences as two of his multiple intelligences

• he notes that we should respect emotional sensitivity, creativity, and motivation as important but different

Emotional Intelligence: the ability to perceive, understand, manage, and use emotions.

Assessing Intelligence

LOQ: What is an intelligence test, and how do achievement and aptitude tests differ?

An intelligence test assesses people’s mental aptitudes and compares them with those of others, using numerical scores

Psychologists classify such tests as either achievement tests, intended to reflect what you have learned, or aptitude tests, intended to predict your ability to learn a new skill.

• An aptitude test is basically an undercover intelligence test

Intelligence Test: a method for assessing an individual’s mental aptitudes and comparing them with those of others, using numerical score

Achievement Test: a test designed to assess what a person has learned

Aptitude Test: a test designed to predict a person’s future performance; aptitude is the capacity to learn.

Early and Modern Tests of Mental Abilities

LOQ: When and why were intelligence tests created, and how do today’s tests differ from early intelligence tests?

People in Western societies have pondered how and why individuals differ in mental ability.

Francis Galton: Presuming Hereditary Genius

Galton wondered if you would be able to measure “natural ability” and to encourage those of high ability to mate with one another

• Cousin of Charles Darwin and was inspired by his natural selection and survival of the fittest

• His quest of a simple intelligence measure failed, he gave us some statistical techniques that we still us

  • Wrote about the inheritance of genius in his book Hereditary Genius

Alfred Binet: Predicting School Achievement

Alfred Binet the task of designing a fair test for children in France

• Binet and Théodore Simon assumed that all children follow the same course of intellectual development but that some develop more rapidly

  • A “dull” child should score much like a typical younger child and a “bright” child-like a typical older child

• The goal was to measure a child’s mental age

  • Children with a mental age of 9 while being 9are average, children with a mental age of 7 while being 9 would be given schoolwork for 7-year-olds

• Theorized that mental aptitude, like athletic aptitude, is a general capacity that shows up in various ways.

  • tested a variety of reasoning and problem-solving questions

  • Items answered correctly could then predict how well other French children would handle their schoolwork.

  • Didn’t make assumptions as to why a particular child was slow, average, or precocious

    • Binet thought more that it was because of the environment

  • Recommended “mental orthopedics” for low scoring children

  • Believed his intelligence test did not measure inborn intelligence as a scale measures weight

    • Was intended to o identify French schoolchildren needing special attention as to improve their education

Mental Age: a measure of intelligence test performance devised by Binet; the level of performance typically associated with children of a certain chronological age. Thus, a child who does as well as an average 8-year-old is said to have a mental age of 8.

Lewis Terman: Measuring Innate Intelligence

Lewis Terman tried to use Binet’s testing on children in California

• French norms didn’t work with kids from California

• Revised it so it would be today’s version

  • Called the Stanford-Binet

• Promoted the use of widespread intelligence testing to “take account of the inequalities of children in original endowment”

  • Assessed their “vocational fitness”

• envisioned that the use of intelligence tests would “ultimately result in curtailing the reproduction of feeble-mindedness and in the elimination of an enormous amount of crime, pauperism, and industrial inefficiency”

  • Helped develop new tests with the U.S. government to evaluate new immigrants and army recruits for WWI

William Stern developed the IQ (intelligence quotient) test

• A person’s mental age dived by their actual age and multiplied by 100

  • An average child whose mental and actual age match up has an IQ of 100

  • A child who is 8 and has a mental age of a 10-year-old has an IQ of 125

• Worked well on children but not as well on adults

  • Instead, they assigned a score that represented the test-taker’s performance relative to the average performance of others of the same age

  • For around 68% of people, their IQ is between 85 and 115

Stanford-Binet: the widely used American revision (by Terman at Stanford University) of Binet’s original intelligence test.

Intelligence Quotient (IQ): defined originally as the ratio of mental age (ma) to chronological age (ca) multiplied by 100 (thus, IQ = ma/ca × 100). On contemporary intelligence tests, the average performance for a given age is assigned a score of 100.

David Wechsler: Testing Separate Strengths

David Wechsler created the most widely used individual intelligence test

• Wechsler Adult Intelligence Scale (WAIS)

  • Had a version for school-aged children (Wechsler Intelligence Scale for Children [WISC])

• The 2008 WAIS consists of 15 subtest including

  • Similarities—reasoning the commonality of two objects or concepts (“In what way are wool and cotton alike?”)

  • Vocabulary—naming pictured objects, or defining words (“What is a guitar?”)

  • Block Design—visual abstract processing

  • Letter-Number Sequencing—on hearing a series of numbers and letters, repeating the numbers in ascending order, and then the letters in alphabetical order (“R-2-C-1-M-3”)

Principles of Test Construction

LOQ: What is a normal curve, and what does it mean to say that a test has been standardized and is reliable and valid?

Standardization

If you then take the test following the same procedures, your score will be meaningful when compared with others

• This is called standardization

Scores from tests typically form a bell curve, or a normal curve

• The curves highest point is the average score

  • This is 100 on the intelligence test

• Moving towards either extreme, there are fewer and fewer people

  • This happened for both the Stanford-Binet and Wechsler tests

    • A performance higher than all but 2.5 percent of all scores earns an intelligence score of 130

    • performance lower than 97.5 percent of all scores earns an intelligence score of 70.

Because of improved nutrition, people have gotten taller as well as smarter

• But in Britian after the war, lower-class children gained the most from improved nutrition, yet the intelligence performance gains were greater among upper-class children.

• the higher twentieth-century birthrates among those with lower scores would shove human intelligence scores downward

Standardization: defining uniform testing procedures and meaningful scores by comparison with the performance of a pretested group.

Normal Curve: the bell-shaped curve that describes the distribution of many physical and psychological attributes. Most scores fall near the average, and fewer and fewer scores lie near the extremes.

Reliability

where you stand in comparison to a standardization group still won’t say much about your intelligence unless the test has reliability

• reliable test gives consistent scores, no matter who takes the test or when they take it.

  • To do this researchers test people many times, splitting the test in half (split-half: agreement of odd-question scores and even-question scores) test with alternative forms of the test, or retest with the same test (test-retest)

  • The higher the correlation between the two scores, the higher the test’s reliability

    • Stanford-Binet, the WAIS, and the WISC are very reliable after early childhood

Reliability: the extent to which a test yields consistent results, as assessed by the consistency of scores on two halves of the test, on alternative forms of the test, or on retesting.

Validity

High reliability does not ensure a test’s validity

• Ex. using a miscalibrated tape measure to measure people’s heights and you would get very reliable results, but faulty height results would not be valid.

Tests that tap the pertinent behavior, or criterion, have content validity

• Ex. a road test for a driver’s license has content validity because it samples the tasks a driver routinely faces.

Intelligence test are expected to have predictive validity

• They should predict the criterion of future performance, and to some extent they do.

According to critics, general aptitude test are not as predictive as they are reliable

• the predictive power of aptitude tests peaks in the early school years and weakens later

• Academic aptitude test scores are reasonably good predictors of achievement for children ages 6 to 12

Validity: the extent to which a test measures or predicts what it is supposed to

Content Validity: the extent to which a test samples the behavior that is of interest.

Predictive Validity: the success with which a test predicts the behavior it is designed to predict; it is assessed by computing the correlation between test scores and the criterion behavior. (Also called criterion-related validity.)

The Dynamics of Intelligence

Stability or Change?

Cross-Sectional Study: research that compares people of different ages at the same point in time.

Longitudinal Study: research that follows and retests the same people over time.

Aging and Intelligence

LOQ: How does aging affect crystallized and fluid intelligence?

Results  of cross-sectional studies showing that older adults give fewer correct answers on intelligence tests than do younger adult

• David Wechsler concluded that “the decline of mental ability with age is part of the general [aging] process of the organism as a whole.”

After colleges in the 1920s began giving intelligence tests to entering students, psychologists saw their chance to study intelligence longitudinally

• Retested the same cohort over a period of years

  • Found that until late in life, intelligence remained stable. On some tests, scores even increased, due partly to experience with the tests

• Optimistic results from longitudinal studies challenged the presumption that intelligence sharply declines with age

Our age-and-intelligence questions depend on what we assess and how we assess it

• Crystallized intelligence increases up to old age

• Fluid intelligence decreases beginning in the twenties and thirties, slowly up to age 75 or so, then more rapidly, especially after age 85

We win and lose with our mind as we age

• We lose recall memory and processing speed

• We gain vocabulary and knowledge

• Fluid intelligence may decline

  • Some older adults’ social reasoning skills increase

Age-related cognitive differences help explain why older adults are less likely to embrace new technologies

• fluid intelligence is at its peak in late twenties or early thirties

Cohort: a group of people sharing a common characteristic, such as from a given time period.

Crystallized Intelligence: our accumulated knowledge and verbal skills; tends to increase with age.

Fluid Intelligence: our ability to reason speedily and abstractly; tends to decrease with age, especially during late adulthood.

Stability Over the Life Span

LOQ: How stable are intelligence test scores over the life span?

For most children, casual observation and intelligence tests before age 3 only modestly predict their future aptitudes

• By age 4, performance on intelligence tests begins to predict their adolescent and adult scores

• consistency of scores over time increases with the age of the child

• By age 11, the stability becomes impressive

  • Discovered by Ian Deary

Children and adults who are more intelligent also tend to live healthier and longer lives. There are 4 possible reason why:

• Intelligence facilitates more education, better jobs, and a healthier environment.

• Intelligence encourages healthy living: less smoking, better diet, more exercise.

• Prenatal events or early childhood illnesses might have influenced both intelligence and health.

• A “well-wired body,” as evidenced by fast reaction speeds, perhaps fosters both intelligence and longevity

Extremes of Intelligence

LOQ: What are the traits of those at the low and high intelligence extremes?

The Low Extreme

Intellectual disability  is a developmental condition that is apparent before age 18

• Sometimes with a known physical cause such as Down Syndrome

To be diagnosed with an intellectual disability, a person must meet two criteria

• low intellectual functioning as reflected in a low intelligence test score

  • Lowest 3% of the general population

• the person must have difficulty adapting to the normal demands of independent living, as expressed in three areas: conceptual, social, and practical

Because of the Flynn effect, intelligence tests are periodically restandardized and intellectual-disability test score boundary can shift.

• Depending on the testing method, two people with the same ability level could be classified differently

• intelligence test scores can mean life or death

  • the Flynn effect means fewer Americans are now eligible for execution (in 2002 the U.S. Supreme Court ruled that the execution of people with an intellectual disability—defined as a test score of below 70—is “cruel and unusual punishment.)

  • This changed in 2014 when the Supreme Court recognized the imprecision and arbitrariness of a fixed cutoff score of 70, and required states with death row inmates who have scored just above 70 to consider other evidence

Intellectual Disability: a condition of limited mental ability, indicated by an intelligence test score of 70 or below and difficulty adapaing to the depends of life.

The High Extreme

Children whose intelligence test scores indicate extraordinary academic gifts mostly thrive

• Terman studied more than 1500 California schoolchildren with IQ scores over 135

  • These children (later called the “Termites”) were healthy, well-adjusted, and unusually successful academically

  • Over the next 70 years, most people in Terman’s group had attained high levels of education

    • Many were doctors, lawyers, professors, scientists, and writers

Critics and proponents of gifted education both agree on this:

• Children have differing gifts, whether at math, verbal reasoning, art, or social leadership

  • Some children exhibit exceptional potential or talent in a given domain

• By providing appropriate placement suited to each child’s talents, we can promote both equity and excellence for all

Genetic and Environmental Influences on Intelligence

Twin and Adoption Studies

LOQ: What evidence points to a genetic influence on intelligence, and what is heritability?

People who share the same genes also share mental abilities

• The intelligence test scores of identical twins raised together are nearly as similar as those of the same person taking the same test twice

• Scans reveal that identical twins’ brains have similar gray- and whitematter volume, and the areas associated with verbal and spatial intelligence are virtually the same

  • Their brains also show similar activity while doing mental tasks

• 200 researchers pooled their data on 126,559 people, all of the gene variations analyzed accounted for only about 2 percent of the differences in educational achievements

Some evidence points to enviroment effects:

• Where environments vary widely, as they do among children of lesseducated parents, environmental differences are more predictive of intelligence scores

• Adoption enhances the intelligence scores of mistreated or neglected children

• The intelligence scores of “virtual twins”—same-age, unrelated siblings adopted as infants and raised together

  • This suggests a modest influence of their shared environment.

Heritability: the proportion of variation among individuals in a group that we can attribute to genes. The heritability of a trait may vary, depending on the range of populations and environments studied.

Environmental Influence

LOQ: What does evidence reveal about environmental influences on intelligence?

Early Enviromental Influences

Children developed little sense of personal control over their environment

• Extreme deprivation was bludgeoning native intelligence

The dramatic effects of early experiences and the impact of early intervention

• J. McVicker Hunt began a training program for the Iranian caregivers, teaching them to play language-fostering games with 11 infant

  • imitated the babies’ babbling, engaged them in vocal follow-the-leader, and taught them sounds from the Persian language

    • Very dramatic results: the infants could name more than 50 objects and body parts by 22 months

  • His findings are an extreme case of a more general finding:

    • Poor environmental conditions can depress cognitive development such as schools with many poverty-level children often have less-qualified teachers

Poverty-related stresses also impede cognitive performance

• People’s worries and distractions consume cognitive bandwidth and can diminish their thinking capacity

• Poverty can deplete cognitive capacity.

Extreme conditions such as sensory deprivation, social isolation, poverty can slow normal brain development

• There is no environmental recipe for fast-forwarding a normal infant into a genius

Schooling and Intelligence

Early Intervention

schooling is one intervention that pays intelligence score dividends

• Schooling and intelligence interact, and both enhance later income

• Hunt believed that education boosted children’s chances for success by developing their cognitive and social skills

Genes and experience weave the fabric of intelligence

• Epigenetics is one field that studies the nature and nurture process

What we accomplish with out intelligence is based on our beliefs and motivation

• Motivation can affect intelligence test performance

Growth Mindset

Carol Dweck believed that intelligence is changeable fosters a growth mindset, a focus on learning and growing.

• Teaches young teens that the brain is like a muscle, growing stronger with use as neuron connections grow

• a growth mindset and disciplined effort enhance achievement

Group Differences in Intelligence Test Scores

Gender Similarities and Differences

LOQ: How and why do the genders differ in mental ability scores?

Our intelligence differences between men and women are small

• men estimate their own intelligence higher than do females

Most people find differences more newsworth

• Girls outpace boys in spelling, verbal fluency, locating objects, detecting emotions, and sensitivity to touch, taste, and color

• Boys outperform girls in tests of spatial ability and complex math problems, though in math computation and overall math performance

Steven Pinker argued that biology affects gender differences in life priorities

• Women’s somewhat greater interest in people versus men’s in money and things

• Men are more interested in risk-takinf and are more reckless

• Across cultures, these differences become more stable influenced by prenatal hormones

  • observed in genetic boys raised as girls

social influences also construct gender

• Stephen Ceci and Wendy Williams reported that culturally influenced preferences help explain why American women, more than men, avoid math-intensive vocations.

• Social expectations and different opportunities also shape boys’ and girls’ interests and abilities

  • In Russia, teen girls have outperformed boys in n international science exams; but in North America and Britian, boys in an international

  • In more gender-equal cultures such as in Sweden and Iceland, there is a very small gender math gap

Racial and Ethnic Similarities and Differences

LOQ: How and why do racial and ethnic groups differ in mental ability scores?

There are two facts that are agreed upon group-differences

• Racial and ethnic groups differ in their average intelligence test scores.

• High-scoring people (and groups) are more likely to attain high levels of education and income.

• Ex. Caucasian Americans have outscored African-Americans on intelligence test scores,

Zealanders of European descent outscore native Maori New Zealanders

• group differences such as these provide little basis for judging individuals

• When African Americans and caucasian americans receive the same pertinent knowledge, they both exude similar processing skills

Heredity contributes to individual differences in intelligence

• group differences in a heritable trait may be entirely environmental

  • Although individual performance differences may be substantially genetic, the group difference is not

We are all very genetically similar

• The average genetic difference between completely different groups from around the world are still genetically similar, some more than others

Race is not a neatly defined biological category

• Most social scientists see race primarily as a social construction without well-defined physical boundaries

Countries whose economies create a large wealth gap between rich and poor tend also to have a large rich-versus-poor intelligence test score gap

• people in poorer regions have the lowest intelligence test scores, and those in wealthier regions have the highest

• educational policies predict national differences in intelligence and knowledge tests

In different eras, different ethnic groups have experienced golden ages— periods of remarkable achievement.

• Cultures rise and fall over centuries; genes do not.

  • That fact makes it difficult to attribute a natural superiority to any racial or ethnic group.

The Question of Bias

LOQ: Are intelligence tests inappropriately biased? How does stereotype threat affect test-takers’ performance?

Racial differences in intelligence divides into three camps

• There are genetically disposed racial differences in intelligence.

• There are socially influenced racial differences in intelligence.

• There are racial differences in test scores, but the tests are inappropriate or biased.

Two Meanings of Bias

test-makers’ expectations can introduce bias in an intelligence test

Test-Takers’ Expectations

Steven Spencer and his colleagues gave a difficult math test to equally capable men and women

• women did not do as well—except when they had been led to expect that women usually do as well as men on the test

Claude Steele and Joshua Aronson saw this observed this self-fulfilling stereotype threat when Black students performed worse after being reminded of their race just before taking verbal aptitude tests

• stereotype threat may impair attention, performance, and learning

  • This helps explain why African-Americans have scored higher when tested by African-Americans than when tested by caucasians

• Steele concluded that telling students they probably won’t succeed functions as a stereotype that can erode performance

Tests are not biased in the scientific sense of failing to make valid statistical predictions for different group

• They are biased in the fact that sensitivity to performance differences caused by cultural experience.

• They do also discriminate but not at the same time

  • The use is to distinguish among individuals, but they have another purpose to reduce discrimination by decreasing reliance on subjective criteria for school and job placement

Stereotype Threat: a self-confirming concern that one will be evaluated based on a negative stereotype.