Module 13

1
Module 13

• Intelligence

Stillwater High School Psychology
Department Spring term 2007
2
DEFINING INTELLIGENCE

• Two-factor theory
• Psychometric approach
• measures or quantifies cognitive abilities or
  factors that are thought to be involved in
  intellectual performance
• Two-factor theory,
• by Charles Spearman
• says that intelligence has two factors
• general mental ability factor g
• represents what different cognitive tasks have in
  common
• specific factors which include specific mental
  abilities such as mathematical, mechanical, or
  verbal skills s

3
DEFINING INTELLIGENCE (CONT.)

• Multiple-intelligence theory
• Gardners multiple-intelligence theory
• Howard Gardner
• instead of one kind of general intelligence,
  there are at least seven different kinds which
  include
• verbal intelligence
• musical intelligence
• logical mathematical intelligence
• spatial intelligence
• body movement intelligence (to understand
  oneself)
• intelligence to understand others

4
DEFINING INTELLIGENCE (CONT.)

• Triarchic theory
• Robert Sternberg
• says that intelligence can be divided into three
  different kinds of reasoning processes
• uses analytical or logical thinking skills that
  are measured by traditional intelligence tests
• uses problem-solving skills that require creative
  thinking and the ability to learn form experience
• uses practical thinking skills that help a person
  adjust to, and cope with, his or her
  sociocultural environment

5
MEASURING INELLIGENCE

• Earlier attempts to measure intelligence
• head size and intelligence
• Francis Galton
• noticed that intelligent people often had
  intelligent relatives and concluded that
  intelligence was, to a large extent, biological
  or inherited
• low correlation between head size and
  intelligence
• using head size as a measure of intelligence was
  abandoned in favor of using skull or brain size

6
p284 BRAIN SIZE
7
MEASURING INELLIGENCE

• Earlier attempts to measure intelligence
• Brain size and intelligence
• Paul Broca
• claimed there was a relationship between size of
  brain and intelligence
• larger brains indicating more intelligence
• later reanalysis of Brocas data indicted that
  measures of brain size proved to be unreliable
  and poorly correlated with intelligence

8
MEASURING INTELLIGENCE (CONT.)

• Earlier attempts to measure intelligence
• brain size and achievement
• enormous variation in brain size and achievement
• brain size, sex differences, and intelligence
• womens brains weigh about 10 less than mens
• little or no difference in intelligence between
  men and women
• larger size of mens brains does not result in
  higher IQs

9
MEASURING INTELLIGENCE (CONT.)

• Binets breakthrough
• Alfred Binet
• believed that intelligence was a collection of
  mental abilities and that the best way to assess
  intelligence was to measure a persons ability to
  perform cognitive tasks, such as understanding
  the meanings of words or being able to follow
  directions
• Binet-Simon Intelligence Scale
• contained items arranged in order of increasing
  difficulty
• measured vocabulary, memory, common knowledge,
  and other cognitive abilities

10
MEASURING INTELLIGENCE (CONT.)

• Binets breakthrough
• mental age measure of intelligence
• Binet and Simon revised their intelligence scale
  to solve several problems in their original scale
• mental age
• method of estimating a childs intellectual
  progeress by comparing the childs score on an
  intelligence test to the scores of average
  children of the same age

11
MEASURING INTELLIGENCE (CONT.)

• Formula for IQ
• Intelligence quotient
• computed by dividing a childs mental age (MA),
  as measured in an intelligence test, by the
  childs chronological age (CA) and multiplying
  the result by 100

12
p285 FORMULA FOR IQ
13
MEASURING INTELLIGENCE (CONT.)

• Wechsler Intelligence Scale
• most widely used IQ tests
• Wechsler Adult Intelligence Scale (WAIS-III),
  ages 16 and older
• Wechsler Intelligence Scale for Children
  (WISC-III) for children ages 3-16
• both have items that are organized into various
  subtests.
• verbal section
• performance section
• verbal and performance combined give a single IQ

14
MEASURING INTELLIGENCE (CONT.)

• Two characteristics of tests
• Validity
• means that the test measures what it is supposed
  to measure
• Reliability
• refers to consistency score on a test at one
  point in time should be similar to the score
  obtained by the same person on a similar test at
  a later point in time

15
DISTRIBUTION USE OF IQ SCORES

• Normal distribution of IQ scores
• Normal distribution
• refers to a statistical arrangement of scores so
  that they resemble the shape of a bell and, thus,
  is said to be a bell-shaped curve

16
p288 IQ CHART
17
DISTRIBUTION USE OF IQ SCORES (CONT.)

• Mental retardation IQ scores
• Mental retardation
• refers to a substantial limitation in present
  functioning that is characterized by
  significantly subaverage intellectual
  functioning, along with related limitations in
  two of ten areas, including communication,
  self-care, home living, social skills, and
  safety.
• borderline mentally retarded IQs from 50 to 75
• mildly/moderately mentally retarded IQs from 35
  to 50
• severely/profound mentally retarded IQs from 20
  to 40

18
DISTRIBUTION USE OF IQ SCORES (CONT.)

• Mental retardation IQ scores
• Causes
• Organic retardation
• results from genetic problems or brain damage
• Cultural-familial retardation
• results from a greatly impoverished environment.

19
DISTRIBUTION USE OF IQ SCORES (CONT.)

• Vast majority IQ scores
• about 95, have scores that fall between 70 and
  130
• Gifted IQ scores
• Moderately gifted
• usually defined by an IQ score between 130 and
  150
• Profoundly gifted
• usually defined by an IQ score around 180 or above

20
NATURE-NURTURE QUESTION

• Definitions
• asks how nature-hereditary or genetic
  factors-interacts with nurture-environmental
  factors-in the development of a persons
  intellectual, emotional, personal, and social
  abilities
• Twin studies
• Fraternal twins
• like siblings (brothers and sisters), develop
  from separate eggs and 50 of their genes in
  common

21
NATURE-NURTURE QUESTION (CONT.)

• Twin studies
• Identical twins
• develop from a single egg and thus have identical
  genes, which means that they have 100 of their
  genes in common
• Interaction of nature and nurture
• when researchers report that genetic factors
  influence intelligence (IQ scores)
• mean that genetic factors influence cognitive
  abilities to varying degrees, depending on the
  environment

22
NATURE-NURTURE QUESTION (CONT.)

• Adoption studies
• children with limited social-educational
  opportunities and low IQs were adopted by parents
  who could provide increased social-educational
  opportunities
• studies show that children with poor educational
  opportunities and low IQ scores can show an
  increase in IQ scores when they are adopted into
  families that provide increased educational
  opportunities

23
NATURE-NURTURE QUESTION (CONT.)

• Interaction nature and nurture
• Heritability
• number that indicates the amount or proportion of
  some ability, characteristic, or trait that can
  be attributed to genetic factors (nature)
• Reaction range
• indicates the extent to which traits, abilities,
  or IQ scores may increase or decrease as a result
  of interaction with environmental factors