Unit 11: Testing and Individual Differences

Unit 11 - Overview Introduction to Intelligence Assessing Intelligence The Dynamics of Intelligence Studying Genetic and Environmental Influences on IntelligenceStudying Genetic and Environmental Influences on Intelligence Group Differences and the Question of Bias Click on the any of the above hyperlinks to go to that section in the presentation.

Module 60: Introduction to Intelligence

Is Intelligence One General Ability or Several Specific Abilities? Intelligence is the ability to learn from experience, solve problems, and use knowledge to adapt to new situations. An intelligence test assesses people’s mental abilities and compares them with others, using numerical scores

Is Intelligence A General Ability or Several Specific Abilities? Spearman’s General intelligence (g) – a general intelligence factor that underlies specific mental abilities and is therefore measured by every task on an intelligence testGeneral intelligence –Factor analysis – statistical procedure thatFactor analysis identifies clusters of related items (factors) on a test and is used to identify different dimensions of performance Comparison to athleticism – many traits work together: balance, coordination, mental skill g

Is Intelligence A General Ability or Several Specific Abilities? Thurstone’s counter argument – did not rank people on a single scale of general aptitude. He used different tests to measure mental abilities: word fluency, verbal comprehension, spatial ability, perceptual speed, inductive reasoning and memory. But those who excelled in one of these clusters generally excelled in many. G Factor is probably true! g

Theories of Multiples Intelligences: Garner’s Eight Intelligences Savant syndrome- score low on intelligence tests but have specialized intelligenceSavant syndrome Many are on autistic spectrum Kim Peek – the “real Rain Man” bIhttps:// bI Flo and Kay – female savant twins 4KOhgvOM

Theories of Multiples Intelligences: Garner’s Eight Intelligences Alfred Binet’s Intelligence Tests Gardner’s Multiple Intelligences The MI Song: c c

Theories of Multiples Intelligences: Garner’s Eight Intelligences –Gardner’s Eight Intelligences –Linguistic –Logical-mathematical –Musical –Spatial –Bodily-kinesthetic –Intrapersonal –Interpersonal –Naturalist

Theories of Multiples Intelligences: Garner’s Eight Intelligences High cognitive ability scores predict attainments but Grit – to be successful you must combine talent with grit – you must be conscientious, well- connected, and doggedly energetic

Sternberg’s Three Intelligences –Analytical (academic problem-solving intelligence e.g. tests –Creative intelligence – reacting to novel situations with creative problem solving –Practical intelligence – managing everyday tasks - Multiple abilities contribute to life success

Emotional Intelligence Emotional intelligence: the ability toEmotional intelligence –Perceive emotions –Understand emotions –Manage emotions –Use emotions for adaptive or creative thinking –Emotionally intelligent people achieve higher quality social interactions

Is Intelligence Neurologically Measurable? Brain Size & Complexity Brain size studies- intelligence correlates with brain size on MRI (frontal & parietal lobes) Einstein’s brain – 15% ↑ parietal lobe! Brain complexity studies –Neural plasticity –Gray matter (neurons) versus white matter (axons)

Brain Function Neural processing/perceptual speed are associated with intelligence- ??? (show stimulus on left, mask it with image on right and ask the question below)

Origins of Intelligence Testing Francis Galton’s “natural ability” intelligence testing (cousin of Darwin). He measured –Reaction time –Sensory acuity –Muscular power –Body proportions Theories disprovin Idea of “hereditary genius:” nature versus nurture persists

Alfred Binet: Predicting School Achievement Alfred Binet –Identifying French school children in need of assistance Mental ageMental age: measure of intelligence test performance. It is the chronological age that most typically corresponds to a given level of performance.

Lewis Terman: The Innate IQ Stanford-Binet Test – revised form of Binet’s test for intelligenceStanford-Binet –Lewis Terman- believed testing revealed genetic intelligence –Terman added new age norms

Lewis Terman: The Innate IQ Intelligence quotient (IQ) IQ = (mental age/chronological age) X 100 IQ of 100 is considered average Original test works well with children, not adults IQ term is still used but represent the test takers performance relative to average performance of others of same age

Modern Tests of Mental Abilities Achievement tests – what you have learned, e.g. ACTAchievement tests Aptitude tests – predict ability to learn, e.g. SATAptitude tests

Modern Tests of Mental Abilities Wechsler Adult Intelligence Scale (WAIS) –Wechsler Intelligence Scale for Children (WISC) –15 subtests assess verbal comprehension, perceptual organization, working memory, processing speed

Principles of Test Construction Standardization Normal curve (bell curve)Normal curve

Principles of Test Construction Standardization Flynn effect

Principles of Test Construction Reliability Reliability- a test yields consistent results on retestingReliability –Scores correlate: –Test-retest reliability –Split-half reliability- consistent scores on two halves of the test

Principles of Test Construction Validity Validity – test measures what it is supposed to measure or predictValidity –Content validityContent validity –Predictive validityPredictive validity

Stability-Change:Aging & Intelligence Cross-Sectional Evidence – study many people at one point in time- looked like intelligence declined with age BUT Longitudinal Evidence –Cohorts were studied:Cohort Same people studied over long time periods and then intelligence was stable

Stability-Change? Aging &Intelligence It all depends –Crystallized intelligence – our accumulated knowledge – increases with ageCrystallized intelligence –Fluid intelligence – ability to reason speedily and abstractly – decreases with ageFluid intelligence

Extremes of Intelligence: The Low Extreme Intellectual disability –Mental retardation –Down syndromeDown syndrome 21 st chromosome –Mainstreamed

Extremes of Intelligence: The High Extreme Terman’s study of gifted children Appropriate developmental placement is key for all

Twin and Adoption Studies Identical twin studies- test results are same as if same person had taken the test twice –Polygenetic –Heritability – extent to whichHeritability intelligence can be attributed to genetic variation (.5 to.8) Adoptive children studies – in childhood, intelligence correlates modestly with adoptive siblings. Mental similarities wane with age- more genetic influence and similarity

Heritability

Environmental Influences Early environmental influences –Tutored human enrichment –Targeted training Schooling and intelligence –Project Head Start Intelligence is likely a combination of genes and environmental exposures

Group Differences in Intelligence Tests: Gender Similarities & Differences Girls – better at spelling & verbal ability, sensation & emotion-detecting ability Boys – spatial ability; extremes of intelligence high and low But, learning and experience have great influence Group differences in intelligence are largely environmental exposures

Racial & Ethnic Similarities/Differences Ethnic similarities & ethnic differences Race is not a defined biological category – no differences when environment is considered

Are Intelligence Tests Inherently Biased? Two meanings of bias: Popular sense – yes because tests are culturally based Scientific sense – not biased if test is valid Test-taker’s expectations Stereotype threatStereotype threat – a self-confirming concern that one will be evaluated based on a negative stereotype

Intelligence = mental quality consisting of the ability to learn from experience, solve problems, and use knowledge to adapt to new situations.

Intelligence Test = a method of assessing an individual's mental aptitudes and comparing them with those of others, using numerical scores.

General Intelligence (g) = a general intelligence factor that, according to Spearman and others, underlies specific mental abilities and is therefore measured by every task on an intelligence test.

Factor Analysis = a statistical procedure that identifies clusters of related items (called factors) on a test; used to identify difference dimensions of performance that underlie a person’s total score.

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

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

Mental Age = a measure of intelligence test performance devised by Binet; the chronological age that most typically corresponds to a given level of performance. Thus, a child who does as well as the average 8-year-old is said to have a mental age of 8.

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 X 100). On contemporary intelligence tests, the average performance for a given age is assigned a score of 100, with scores assigned to relative performance above or below average.

Achievement Tests = tests designed to assess what a person has learned.

Aptitude Tests = tests designed to predict a person’s future performance; aptitude is the capacity to learn.

Wechsler Adult Intelligence Scale (WAIS) = the WAIS is the most widely used intelligence test; contains verbal and performance (nonverbal) subtests.

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

Normal Curve = a symmetrical, 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 = the extent to which a test yields consistent results, as assessed by the consistency of scores on two halves of the test, on alternate forms of the test or on retesting.

Validity = the extent to which a test measures or predicts what it is suppose 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).

Cohort = a group of people 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 during late adulthood.

Intellectual Disability = a condition of limited mental ability, indicated by an intelligence score of 70 or below and difficulty in adapting to the demands of life. Formerly referred to as mental retardation

Down Syndrome = a condition of mild to severe intellectual disability and associated physical disorders caused by an extra copy of chromosome 21.

Hereditability = the proportion of variation among individuals that we can attribute to genes. The hereditability of a trait may vary, depending on the range of populations and environments studied.

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