Intelligence

• intelligence: usually defined as the ability to profit from experience, acquired knowledge, think abstractly, act purposefully, and/or adapt to changes in the environment.

Theories of Intelligence• Spearman’s g-factor: a general intellectual

ability assumed by many theorists to underlie specific mental abilities and talents

• Cattell’s clusters– crystallized intelligence: abilities like reasoning and

verbal and numerical skills• highly influenced by experience and formal education

– fluid intelligence: visual and spatial imagery, rote memory.

• less influenced by experience and education

Theories of Intelligence

• Howard Gardener – theory of multiple intelligence proposes that

intelligence comprises many separate abilities each of which is relatively independent of each other.

– Types of intelligence: Logical-mathematical, linguistic, spatial, musical, bodily-kinesthetic, interpersonal, and intrapersonal

Intelligence Tests• Alfred Binet

– Memory, vocabulary, and perceptual discrimination

• IQ “intelligence quotient”: a measure of intelligence originally computed by dividing a person’s mental age by his or her chronological age and multiplying by 100

Intelligence Tests• Wechsler Adult Intelligence Scale and

Wechsler Intelligence Scale for Children– divided into two parts: verbal and

performance – Vocabulary, spatial, speed, similarities,

information

• 68% of population has IQ scores between 85 and 115.

• 95% of population has IQ scores between 70 and 130.

Criticisms of IQ tests

• Content- tests assess ability in only a very narrow range of skills– passive verbal understanding, ability to follow

instructions; common sense; scholastic aptitude

• Tests test ability to take tests – close correlation between IQ scores and school

performance– stereotype threat: a burden of doubt a person feels

about his or her performance, due to negative stereotypes about his or her group’s abilities.

Criticisms of IQ tests

• bias against minorities– require mastery of English – questions are culturally based– Speed

• used inappropriately– don’t measure motivation, emotion, and

attitude which affects performance in life– Study by Terman which followed 1500 of top

1% of IQ scores• most differences attributable to motivation

Contributing factors: heredity • Heredity- intelligence is partly inherited• correlation between monozygotic twins reared

together very high

• correlation between monozygotic twins reared apart also high– higher than siblings reared together

• However, monozygotic twins share similar environment because adoption agencies tend to match environments and they also shared same prenatal environment

Contributing factors: environment

• Environment also affects intelligence• prenatal environment impacts IQ

– Prenatal vitamins

• IQ of children in orphanages in Iowa (Skeel, 1930)– Orphans who had little adult interaction had

“subnormal” IQ– Children who had were placed in adult ward had

increased IQ from the retarded range to normal. – Concluded that children need to have someone to talk

to them, play with them, and teach them to be able to reach their full potential.

Contributing factors: motivation• Motivation affects intellectual ability• Comparing Chinese and Japanese

students with American students – Beliefs: American students and parents more

likely to believe that ability is innate

– Standards: American parents have lower standards for their children’s performance

– Values: American students don’t value education as much as Asian students.

Contributing factors: intervention programs

• Intervention Programs- Milwaukee Project intervened in children’s family life to offset the negative effects of cultural and socioeconomic deprivation

– 40 poor pregnant women whose average IQ was 75

– 20 were given job training and had their children in the infant education center until they were 6 years old.

– 20 were not given any special treatment, just periodic IQ testing

– Children who were in the infant education center had average IQ of 126, 30 points higher than children who did not participate (m=94)

Contributing factors: intervention programs

• Head Start started in 1965– Provides low-income preschoolers age 3-5

educational and social skills before they get to school

– Parents are also encouraged to participate in activities and administration of program

– Graduates of Head Start have boost in cognitive abilities, stay in school longer, more likely to graduate from college