Understanding Intelligence: Theories and Measurements

1. Unit Overview 1. What is Intelligence? 2. Assessing Intelligence 3. The Dynamics of Intelligence 4. Genetic & Environmental Influences on Intelligence Click on the any of the above hyperlinks to go to that section in the presentation.

2. What is Intelligence? • Intelligence • mental quality consisting of the ability to learn from experience, solve problems, & use knowledge to adapt to new situations. • Savant syndrome • Intelligence test • Measure mental aptitude; compare to others; numerical value Would Savant Syndrome be more supportive of Sperman’s or Gardner’s view of intelligence? Why?

3. Intelligence is socially constructed… intelligence is defined according to the attributes that enable success in a particular culture Intelligence tests are used to assess individuals‘ mental aptitudes and compare them with those of others. When we refer to someone's IQ as if it were a fixed and objectively real trait such as height, we commit a reasoning error called… reification

4. Is Intelligence One General Ability or Several Specific Abilities? • Spearman • General intelligence (g) • Factor analysis - - how is this used in intelligence testing? • To answer the question: Is intelligence a single trait or a collection of distinct abilities? • Thurstone’s counter argument • identified seven clusters of primary mental abilities, including word fluency, memory, and inductive reasoning. Supporters of g support numerical IQ score g a general intelligence that underlies successful performance on a wide variety of tasks.

5. Is Intelligence One General Ability or Several Specific Abilities?Theories of Multiple Intelligences • Gardner’s Eight Intelligences • Linguistic • Logical-mathematical • Musical • Spatial • Bodily-kinesthetic • Intrapersonal • Interpersonal • Naturalist Criticism of Gardner’s Theory? criticized for extending the definition of intelligence to an overly broad range of talents

6. Is Intelligence One General Ability or Several Specific Abilities?Theories of Multiple Intelligences

7. Is Intelligence One General Ability or Several Specific Abilities?Theories of Multiple Intelligences • Sternberg’s Three Intelligences • Analytical (academic problem-solving intelligence • Creating intelligence • Practical intelligence The Sternberg-Wagner test measures writing skills, skill in motivating others, and ability to effectively delegate tasks. This test measures which of the intelligences described by Sternberg's triarchic theory of intelligence?

8. Comparing Theories of Intelligence page 528

9. Emotional Intelligence • Emotional intelligence • Perceive emotions • Understand emotions • Manage emotions • Use emotions for adaptive or creative thinking

10. Is Intelligence Neurologically Measurable?Brain Size and Complexity • Brain size studies • .33 • Brain complexity studies • Neural plasticity • More synapses • Gray matter versus white matter

11. Is Intelligence Neurologically Measurable?Brain Function • Perceptual speed • faster cognitive processing may allow for more information to be acquired • Neurological speed

12. Assessing Intelligence

13. Who attempted to assess intellectual strengths by measuring muscular power, sensory acuity, and body proportions?

14. The Origins of Intelligence Testing • Francis Galton’s intelligence testing • Reaction time • Sensory acuity • Muscular power • Body proportions Nature vs. Nurture

15. Modern Intelligence Testing Movement • Alfred Binet • Minimize bias of teacher in indentifying French school children in need of assistance • Mental age • Level of performance typically associated w/ chronological age • General capacity that can manifest itself many ways • Test DOES NOT measure inborn intelligence…single practical purpose

16. The Innate IQ • Stanford-Binet Test • Lewis Terman • adapted test to American children (and adults) • Intelligence quotient (IQ) • IQ = (mental age/chronological age) X 100 • IQ of 100 is considered average • Today’s IQ tests compute performance on test relative to average performance of others of same age

17. Eugenics • Measuring human traits and using the results to encourage only smart & fit people to reproduce. • With Terman’s help, the US evaluated new immigrants & WWI recruits • Some felt test “proved” inferior intelligence of people of non-Anglo-Saxon heritage this belief led to what laws in the 1920’s?

19. “We must not forget that women are, on the average, a little less intelligent than men, a difference which we should not exaggerate but which is, nonetheless, real. “ “We are permitted to suppose that the relatively small size of the female brain depends in part upon her physical inferiority and in part upon her intellectual inferiority.” Germans are smarter than the French” “The German is bigger due to copious amounts of beer & sausage, therefore the brain is larger, however, when adjusted, not of superior intelligence.”

20. A survey of the history of intelligence testing reinforces what important lesson about the scientists whose work we study? Science can be value-laden. Behind a screen of scientific objectivity, ideology sometimes lurks.

21. Simon & Binet = concept of mental age • William Stern = formula for IQ • Lewis Terman = used formula on his Standford-Binet test

22. Modern Tests of Mental Abilities • Achievement tests • Aptitude tests

23. Modern Tests of Mental Abilities • Wechsler Adult Intelligence Scale (WAIS) • the WAIS is the most widely used intelligence test; contains verbal and performance (nonverbal) subtests • Wechsler Intelligence Scale for Children (WISC)

24. Wechler Adult Intelligence Scale

25. Principles of Test ConstructionStandardization • Standardization • a person's test performance can be compared with that of a representative pretested group • Normal curve (bell curve) restandardize

26. Normal Curve

27. Principles of Test ConstructionStandardization • Flynn effect

28. Principles of Test ConstructionStandardization • Flynn effect

29. T/t TEST

30. Principles of Test Construction Researchers assess the correlation between scores obtained on two halves of a single test in order to measure the ________ of a test. • Reliability • Scores correlate • Test-retest reliability • Split-half reliability

31. Principles of Test ConstructionValidity • Validity • Content validity • the extent to which a test samples the behavior that is of interest. • Criterion • 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 the criterion behavior (also called criterion-related validity College Board AP Exams

32. The Dynamics of Intelligence

33. Stability or Change?How stable are intelligence scores over the lifespan? • Intelligence testing through life Infants who habituate sooner to a picture… +.66 Consistency of scores increases w/ age

34. Extremes of IntelligenceThe Low Extreme • Intellectual disability • Mental retardation • 70 or below – 1% • Down syndrome • 21st chromosome • Mainstreamed

35. Extremes of IntelligenceClassifications of Intellectual Disability

36. Extremes of IntelligenceThe High Extreme • Terman’s study of gifted • 1921 • most thrive • Gifted? • tracking by aptitude = self-fulfilling prophecy 110-119 = bright normal 120-129 = superior above 130 = very superior above 150 = gifted

37. Genetic and Environmental Influences on Intelligence

39. genotype vs. phenotype composite of an organism’s observable characteristics or traits inherited instructions within one’s genetic code

40. Twin & Adoption Studies • Identical twin studies • 50% intelligence test score variations can be attributed to genetic variation • similar brain scans • polygenetic • Adoptive children studies • fraternal twins score more alike than other siblings • genetic influences become more apparent as we age compare adopted children with biological parents as well as adoptive parents environment

41. Heritability

42. Heritability

43. Heritability

44. Heritability

45. Correlated Scores

46. Correlated Scores

47. Heritability • NEVER pertains to an individual only to the VARIATION – why people differ • when environments varies widely, environmental differences become more predictive trait differences (g score) • if the environment is exactly the same, heritability would be 100% - variation would have to be due to genetics. low heritability

48. Environmental Influences Hunt • Early environmental influences • Tutored human enrichment • among the poor, environmental conditions can override genetic differences • Targeted training • specific abilities…music • Schooling & intelligence • Project Head Start • growth mindset vs. fixed mindset performance orientation – give up when do poorly on tests

49. Group Differences in Intelligence Test ScoresGender Similarities and Differences • Spelling • Verbal ability • Nonverbal memory • Sensation • Emotion-detecting ability • Math and spatial aptitudes W W W W evolutionary W M M= problem solving W = computation

50. Group Differences in Intelligence Test ScoresEthnic Similarities and Differences • group differences help little w/ judging individuals • group differences could be entirely environmental • individual genetic differences w/in a race are much greater than differences between races *page 553*