Intelligence

What is Intelligence?

• Intelligence is a socially constructed concept• Cultures deem “intelligent” whatever attributes

enable success in those cultures• Intelligence is not a “thing”– One should not say they “have” an IQ of 120– Should say “My score was 120 on the intelligence test”

• High intelligence does more to get you into a profession than it does to make you successful there.

Controversies about Intelligence

• Psychologists define intelligence as: Mental qualities consisting of the ability to learn from experience, solve problems, and use knowledge to adapt to new situations

• Two controversies remain about intelligence– Is intelligence a single overall ability or several

specific abilities?– With the tools neuroscience offers, can we locate

and measure intelligence within the brain?

Intelligence Test

• A method for assessing an individual’s mental aptitudes and comparing them with those of others, using numerical scores–WWI IQ Test–MENSA Test

Intelligence

• Alfred Binet: – Set out to measure mental age– Theorized that mental aptitude is a general

capacity that shows up in various ways– Devised reasoning and problem-solving questions

that might predict school achievement.• Test had a single practical purpose of identifying French

school children needing special attention• Did not speak to the cause of slow, average or

precocious children

Intelligence

• Mental Age:– A measure of intelligence test performance

devised by Alfred Binet– The chronological age that most typically

corresponds to a given level of performance• A child who does well as an average 8 year old is said to

have a mental age of 8

Intelligence

• Stanford-BinetWidely used American version of Binet’s original test– Stanford professor Lewis Terman attempted to use

the test as a measure of inherited intelligence.• Adapted the test to American norms and standards• Terman promoted the widespread use of intelligence

testing

IQ – Intelligence Quotient

• Defined originally as the ratio of mental age to chronological age, multiplied by 100– MA/CA x 100 = IQ

• No longer the formula used (although it is effective for children)– Contemporary intelligence tests use the score of

100 as average score

“g” Factor

• A general intelligence factor that Charles Spearman and others believed underlies specific mental abilities and is therefore measured by every task on an intelligence test– He noted that people often have special abilities, but

that those who score high on verbal intelligence, often score higher than average on other factors• This commonality, “g” factor, underlies all of our

intelligent behavior

Fluid Intelligence

• Fluid Intelligence – Similar to Spearman’s g in that it is thought to

affect all types of problem solving– Refers to the ability to learn new concepts, and

apply old concepts to new problems or in new ways

– Thought of as an innate ability and is not affected by education or experience

– As we get older, our Fluid Intelligence weakens

Crystallized Intelligence

• Crystallized Intelligence– Refers to some particular area of expertise that an

individual has either learned or experienced• Arithmetic or verbal skills

– This form of intelligence gets stronger as we age

Savants

• Savant Syndrome:– A condition in which a person otherwise limited in

mental ability has an exceptional specific skill• An island of brilliance

– Computation, drawing, musical memory

• About 4 in 5 savants are male• Diagnosed with autism, which mostly afflicts males• Savants served as evidence to Gardner the presence of

multiple intelligences

Multiple Intelligences

• Howard Gardner:– Gardner argues that we do not have an intelligence, but

instead we have multiple intelligences• Each are relatively independent of the others

– Eight intelligences• Word Smarts (verbal) – Shakespeare• Number Smarts (mathematics) – Einstein• Music Smarts – Beethoven• Space Smarts (spatial) – DaVinci, Monet• Body Smarts (movement/athleticism) – Michael Jordan• Self Smarts (intrapersonal) – Freud• Nature Smarts – Charles Darwin

Anti-Multiple Intelligences

• Critics of Gardner question whether it makes sense to lump all sorts of abilities under the concept of intelligence.– Intelligence is mental ability, not a talent• Gardner claims that all forms of intelligence have an

intrinsic value– It’s one’s culture and context that place a greater value on

some capacities than on others– Express what people value in a human being

Successful Intelligence

• Theory established by Robert Sternberg– Comprised of three different sub-types of intelligence– Analytical Intelligence – assessed by intelligence tests

which present well-defined problems having a single right answer

– Creative Intelligence – Demonstrated in reacting adaptively to novel situations and generating novel ideas

– Practical Intelligence – Often required for everyday tasks which are frequently ill-defined with multiple solutions

• Sternberg and Gardner agree that multiple intelligences can contribute to life success

Emotional Intelligence

• The ability to perceive, express, understand, and regulate emotions– A critical part of social intelligence• The know-how involved in comprehending social

situations and managing oneself successfully

Emotional Intelligence

• Not necessarily related to academic aptitude• Emotionally intelligent people are self-aware– Can manage their emotions– Delay gratification– Empathy enables them to read others emotions– Know how to encourage, what to say to a grieving

friend, how to manage conflicts well• Emotionally smart

– Often succeed in careers, marriages, and parenting

MEIS

• Multifactor Emotional Intelligence Scale– Developed to assess overall emotional intelligence

and its three components• Perceived Emotions: By recognizing emotions conveyed

by various faces, musical excerpts, graphic design and stories

• Understand Emotions: By recognizing how emotions change over time, predicting differing emotions, and apprehending how emotions blend

• Regulate Emotions: By rating alternative strategies that one could use when facing various real-life dilemmas

Assessing Intelligence

• Aptitude Test: A test designed to predict a person’s future performance– Aptitude is the capacity to learn– Ex. College entrance exam is an aptitude test

• Achievement Test: A test designed to assess what a person has learned – Mr. Colley’s exams are achievement tests

• Differences between the two are not clear cut– Ex. Achieved (learned) vocabulary influences your score on

most aptitude tests, while your aptitudes for learning influence your grades on tests for achievement

Test Construction

• Standardization:– Defining meaningful scores by comparison with the

performance of a pre-tested “Standardization Group”• To enable meaningful comparisons, test-makers first give the

test to a representative sample• When others take the test, their scores can be compared to

the standards defined by the sample

– Standardized test results typically form a normal distribution• 96% of the population scores between 70 and 130 on

intelligence tests• Standard deviation of 15

Test Construction

• Reliability;– A good test must yield dependably consistent

scores• Assessed by the consistency of scores on both halves of

a test, alternate forms of a test or on retesting• The higher the correlation between test-retest or the

split-half the higher the reliability – WAIS, WISC, Stanford-Binet all have reliability of +.9

Test Construction

• Validity:– The extent to which the test actually measures what it is

supposed to measure or predicts what it is supposed to predict• High reliability does not ensure validity

• Content Validity:– The extent to which a test samples the behavior that is of

interest– A driving test that samples driving tasks– Other tests are evaluated in terms of how well they agree with

some criterion• The behavior that a test is designed to predict

Test Construction

• Predictive Validity:– The success with which a test predicts the

behavior it is designed to predict• Assessed by computing the correlation between test

scores and criterion behavior• Aptitude tests must have predictive validity

Extremes of Intelligence

• Low Extreme:– Scores fall below a 70– To be labeled as mental retarded, one must have a low test score

(below 70) and have difficulty adapting to the normal demands of independent living• 1 % of the population

– Down Syndrome• A condition of retardation and associated physical disorders caused by an

extra chromosome in one’s genetic makeup

• High Extreme:– Scores over 130– Most children with extraordinary academic gifts thrive

• Some become isolated, introverted, and live in their own world

Why “Smart” People Sometimes Fail?

• Robert Sternberg has described 20 different stumbling blocks that help explain why even the best measures of intelligence cannot predict success; Top Ten Reasons below

• 1) Lack of Motivation• 2) Lack of Impulse Control: Impulsiveness can get in the way of good performance• 3) Lack of Perseverance: Some people give up too easily, and thus underperform• 4) Using the Wrong Abilities: People might not draw upon the right abilities for the task at hand• 5) Inability to translate thought into action: Some people have good ideas, but can’t do

anything about them• 6) Lack of product orientation: Some people are more concerned with the process of doing,

than with getting the task done• 7) Inability to Complete tasks: Some people will work but never finish the task• 8) Failure to Initiate: Some people are unwilling or unable to being a project; fear of

commitment• 9) Fear of Failure: People may not reach their peak performance because they avoid challenges• 10) Procrastination: Some people cannot work without time pressure; thus put off doing

important work

Genes

• Genetic Influences– There are research studies that clearly support

genetic contribution to intelligence– The intelligence test scores of 10,000 identical twins

reared together are virtually as similar as those of the same person taking the same test twice

– Identical twins reared separately have similar scores• Lower correlation shows environmental effect• 70 % of intelligence score variation can be attributed to

genetic influences

Genes

• With age, genetic influences become more apparent– Contradict the popularly held theory that as we

accumulate life experiences, environmental influences increase

Heritability

• Heritability– The proportion of variation among individuals that we can

attribute to genes• The heritability of a trait may vary• Depending on the range of a populations and environments studied

• For intelligence, heritability is the variation in intelligence tests scores attributable to genetic factors

• We can attribute 50% of the variation in intelligence within a group of people to heredity– Heritability refers to the extent to which differences among

people are attributable to genes• Never pertains to an individual, only to why people differ

Environmental Factors

• Genes make a difference. But heredity doesn’t tell the whole story.

• Early Intervention Effects – Hunt’s study in an Iranian orphanage

• After receiving responsive care-giving, the children made a dramatic turn around

• Native intelligence had been bludgeoned by extreme deprivation• But, with the introduction of human response and nutritional supplements,

the children made great improvements

• Extremely bad environments (malnutrition, sensory deprivation, social isolation) can retard normal brain development– But, the difference between a normal and “enriched” environment

matters much less

Schooling Effects

• Schooling Effects– Schooling and intelligence contribute to each

other • Both also enhance income

• Intelligence scores increases during the school year and fall off over the summer months

• Completing high school elevates intelligence scores vs. children who leave school early

Ethnic Similarities and Differences

• Racial groups differ in their average scores on intelligence tests

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

• Bell curve for:– Whites: 100– Blacks: 85– Hispanics: 90ish

• The difference between Blacks and Whites has diminished as of late – down to 10 points in children – but there is still a gap

• Such group differences provide little basis for judging individuals

Genetic and Environmental Influences

• Group differences in a heritable trait may be entirely environmental– Ex: Give hearing and deaf children an intelligence

test rooted in their culture’s dominant language• Those children with expertise in the language do much

better• Individual performance differences may be genetic, but

the group difference is not• Even perfect heritability within groups would not

eliminate the possibility of a strong environmental impact on the group difference.

Genetic and Environmental Influences

• Environmental factors in the racial gap– Genetics research reveals that under the skin,

races are remarkably similar– Asian students outperform North American

students on math achievement and aptitude tests• Most likely a result of conscientiousness• Spend 30 days more a year in school

Gender Influences

• Gender Similarities and Differences– Gender similarities far out number the differences

but the differences capture more attention• Females are better spellers• Females are more verbally fluent, more sensitive to

touch, taste, and odor; and more capable of remembering words and location of objects.

Gender Influences

• Males and females are almost identical in their average math computation scores– Males however score higher in math problem solving– Average 45 points higher on SAT math portion– Males also do better on spatial ability tests

• Women are much better than men at emotion detection– An ancestral explanation is that mothers needed to

read emotions in their children and would-be lovers