1. Unit 3: Intelligence

2. Part 4: The Genetics of Intelligence

3. Environmental Influences
1980s Iranian orphanage
Infants received little care, care they did receive was not in response to crying, cooing, or other behaviors
Babies learned then that they had little control over their environment
Became passive, typical 2-year-old could not sit up without help, typical 4-year-old could not yet walk

4. Environmental Influences
1980s Iranian orphanage
Training in responsive caregiving given to the workers
Started with playing vocal games with the babies, then teaching them the sounds of the Persian language
By 22 months (1 year & 10 months) all 11 infants could name more than 50 objects
Most were adopted

5. Environmental Influences
Severe disadvantage in environment takes a toll
Unlike children of wealthy families, children of impoverished homes have similar intelligence scores
Indicates that among the poor, environmental conditions can override genetic differences

6. Environmental Influences
Severe disadvantage in environment takes a toll
In addition, schools with lots of poverty-level children have less-qualified teachers, & lower-qualified teachers predict lower test scores

7. Environmental Influences
Malnutrition also affects cognitive development
Severe poverty is associated with malnutrition
When nutritional supplements are provided, poverty’s effect on physical & cognitive development lessens

8. Environmental Influences
Difference between normal and enriched environments matters much less than deprived environments
Extra instruction matters little on children from stimulating environments

9. Environmental Influences
Difference between normal and enriched environments matters much less than deprived environments
However, it does make a difference for children from disadvantaged environments
Quality programs that offer individual attention increase school-readiness and decrease the likelihood of repeating a grade or being placed in special education

10. Environmental Influences
School itself is an intervention
School & intelligence enhance each other and enhance later income
Intelligence scores rise during school months and drop during summer
Those who complete high school have higher scores than those who leave early

11. Environmental Influences
School itself is an intervention
Part of the reason IQ scores have been rising over time is because we require more school and there are more stimulating home environments due to today’s better-educated parents

12. Group Differences Ethnic similarities & differences
2 disturbing but true facts:
Racial groups differ in their average scores on intelligence tests
Bell curve for whites centers around 100, for blacks it is around 85
Handout 11-14

13. Group Differences Ethnic similarities & differences
2 disturbing but true facts:
High-scoring people (and groups) are more likely to attain high levels of education & income
Handout 11-14

14. Group Differences Differences within groups are genetic
Differences between groups are environmental

15. Group Differences So is the racial gap in intelligence environmental?
Well, there are multiple things to consider:
Genetics research reveals that under the skin, the races are remarkably alike
Individual differences within a race are much greater than differences between races

16. Group Differences So is the racial gap in intelligence environmental?
Race is not a neatly defined category
Many argue that race is a purely social construct
People today have much more varied ancestry

17. Group Differences So is the racial gap in intelligence environmental?
Asian students outperform North American students on math achievement & aptitude tests
A recent phenomenon
Asian students also attend school 30% more days per year

18. Group Differences So is the racial gap in intelligence environmental?
We don’t attribute the general difference in scores to genetics, why would we attribute the racial group difference to genetics?
White & black infants score equally well on infant intelligence tests

19. Group Differences So is the racial gap in intelligence environmental?
In different eras, different ethnic groups experience golden ages – periods of remarkable achievement
Cultures rise & fall over centuries, genes do not

20. Gender Differences
Similarities far outnumber differences between the genders
Differences studied more b/c more exciting
Differences:
Spelling: girls are better spellers
Verbal ability: girls are more verbally fluent & more capable of remembering words
Nonverbal memory: girls are better at locating objects

21. Gender Differences Differences:
Sensation: girls are more sensitive to touch, taste, and odor
Underachievement: boys outnumber girls at the low extreme & therefore in special education classes
Math & spatial aptitude: females have the edge in math computation, but boys score higher in math problem solving

22. Gender Differences
Exposure to high levels of male sex hormones during pre-natal period does enhance spatial abilities
Biological AND social influences on gender differences
Male edge in math problem solving grows with age – only detectable after elementary school
Boys have been encouraged to take more math & science classes

23. Gender Differences Emotional intelligence:
Women are better than men at detecting other peoples’ emotions

24. Bias
Are there differences between groups in intelligence test scores because the tests are biased?
Yes
Intelligence tests measure your developed abilities, which reflect your education and experiences

25. Bias
Are there differences between groups in intelligence test scores because the tests are biased? No
Scientific definition of bias: whether a test is less valid for some groups than others
In this statistical meaning of bias, the tests are NOT biased: they do make valid statistical predictions for different groups

26. Stereotype Threat
Stereotype threat: a self-confirming concern that one will be evaluated based on a negative stereotype
When women were told that females typically do just as well as, or better than, men on a math test they did
Black students’ scores were lower on a verbal aptitude test when they took it under conditions designed to make them feel threatened
Women score higher on math tests when no male-test takers are present
Blacks score higher when tested by Blacks than by Whites

27. Stereotype Threat
When you tell students they probably won’t succeed, this stereotype will erode their performance
Many remedial “minority support” programs in education do exactly that
Over time, students “disidentify” with school achievement, detaching their self-esteem from academics
Programs that challenge students to believe in their potential have produced markedly higher grades and lower dropout rates

28. Final Thoughts
Intelligence tests do have benefits: enable schools to recognize who might profit most from early intervention
Intelligence tests can be misinterpreted as literal measures of a person’s worth and fixed potential
Intelligence test scores reflect only one aspect of personal competence
Practical and emotional intelligence matter too