Module 13 Intelligence

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”

DEFINING INTELLIGENCE (CONT.) Multiple-intelligence theory Gardner’s 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

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

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

p284 BRAIN SIZE

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 Broca’s data indicted that measures of brain size proved to be unreliable and poorly correlated with intelligence

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 women’s brains weigh about 10% less than men’s little or no difference in intelligence between men and women larger size of men’s brains does not result in higher IQs

MEASURING INTELLIGENCE (CONT.) Binet’s breakthrough Alfred Binet believed that intelligence was a collection of mental abilities and that the best way to assess intelligence was to measure a person’s 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

MEASURING INTELLIGENCE (CONT.) Binet’s 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 child’s intellectual progeress by comparing the child’s score on an intelligence test to the scores of average children of the same age

MEASURING INTELLIGENCE (CONT.) Formula for IQ Intelligence quotient computed by dividing a child’s mental age (MA), as measured in an intelligence test, by the child’s chronological age (CA) and multiplying the result by 100

p285 FORMULA FOR IQ

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

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

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

p288 IQ CHART

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

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.

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

NATURE-NURTURE QUESTION Definitions asks how nature-hereditary or genetic factors-interacts with nurture-environmental factors-in the development of a person’s 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

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

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

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