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9: Intelligence

9.1 Defining Human Intelligence

  • Intelligence: Capacity for rational thought, purposeful action, and effective adaption.

  • G-factor: Measure of an individual’s overall intelligence as opposed to specific abilities.

  • Fluid intelligence: The ability to solve novel problems involving perceptual speed or rapid insight.

  • Crystallized intelligence: The ability to solve problems using already acquired knowledge.

    Challenges In Defining Intelligence

  • Aptitude: A capacity for learning certain abilities.

  • Multiple Intelligence: Howard Gardner’s theory that there are several specialized types of intellectual ability.

  • 9 Distinct Kinds of Intelligence:

    1. Linguistic (language abilities)

    2. Logical-mathematical (logic and number abilities)

    3. Visual (pictorial abilities)

    4. Musical (music abilities)

    5. Bodily-kinesthetic (physical abilities)

    6. Intrapersonal (self-knowledge)

    7. Interpersonal (social abilities)

    8. Naturalist (ability to understand the natural environment)

    9. Existential (ability to understand spirituality and existence)

  • Robert Sternberg: argued that an important component of intelligence is related to our ability to demonstrate skills that are practical or useful in the environment

    • People are “smart” in different way

  • If intelligence can refer to many things, term becomes somewhat meaningless and impossible to study

    • Intelligence defined as a g has some value because it correlates with many outcomes a culture views as important

    • Western view

    9.2 Measuring Intelligence

    Studying the Science: Characteristics of Good Intelligence Tests

  • Psychometric test: Any measurement of a person’s mental functions.

    Reliability

  • Reliability: The ability of a test to yield the same score, or nearly the same score, each time it is given to the same person.

    • Give to a large number of people and retest them later (test-retest)

    • Determine wheather scores on on half of the test items match scores on the other half (split-half reliability)

    • Compare scores on one version of the test to scores on the other (equivalent-forms reliability)

    Validity

  • Validity: The ability to measure what it purports to measure.

    • Compare test scores to actual performance on some other measure that is known to assess the construct you’re trying to measure (criterion validity)

    Human Diversity and Culture-Fair Intelligence Tests

  • Culture-fair test: A test (such as an intelligence test) designed to minimize the importance of skills and knowledge that may be more common in some cultures than in others.

    Objectivity and Standardization

  • Objective test: A test that gives the same score when different people correct it.

  • Test Standardization: Establishing standards for administering a test and interpreting scores.

    • Norm: An average score for a designated group of people.

    Ways to Measure Intelligence

    General Aptitude Tests

  • General Aptitude: Measures a narrower range of abilities than intelligence tests do

  • Special Aptitude test: A test to predict a person’s likelihood of succeeding in a particular area of work or skill.

  • Multiple Aptitude Test: A test that measures two or more aptitudes.

    • Tend to be more like an intelligence test

    • ACT, SAT, CQT

  • General intelligence test: A test that measures a wide variety of intellectual abilities.

    Stanford Binet Intelligence Test

  • Alfred Binet: Compared test scores of individual children to average scores for their age

    • Lewis Terman revised it for use in North America and renamed it

    • Current version - Stanford Binet Intelligence Scales, 5th Edition (SB5)

    • Measures general intelligence

  • SB5 measures five cognitive factors

    • Fluid Reasoning

      • Ability to reason in unfamiliar situations

    • Knowledge

      • Knowledge of a wide range of topics

    • Quantitative Reasoning - Problem-solving involving numbers

    • Visual-Spatial Processing

      • Reproducing patterns, and puzzles; copying geometric shapes

    • Working Memory

      • Use of short-term memory

    The Wechsler Tests

  • Wechsler Adult Intelligene Scale, 4th edition (WAIS-IV)

    • Similar to SB5

      • yields a single overall intelligence (g-factor)

  • Performance (nonverbal) intelligence: Intelligence measured by solving puzzles, assembling objects, completing pictures, and other nonverbal tasks.

  • Verbal intelligence: Intelligence measured by answering questions involving vocabulary, general information, arithmetic, and other languages- or symbol-oriented tasks.

    The Results of Intelligence Tests: Intelligence Quotients

  • Mental age: In intelligence testing, the average cognitive ability is displayed by people of a given age.

  • Intelligence quotient (IQ): Mental age divided by chronological age times 100.

  • Normal distribution: Bell-shaped curve of scores with a large number in the middle and very few on the high and low ends.

  • Deviation IQ: An IQ obtained statistically from a person’s relative standing in his or her age group—that is, how far above or below average the person’s score is relative to other scores.

    9.3 Intellectual Giftedness and Disability

    Identifying Gifted Children

  • Giftedness: The possession of either a high IQ or special talents or aptitudes.

    Identifying Individuals with Intellectual Disabilities

  • Intellectual disability (intellectual developmental disorder): The presence of a developmental disability, a formal IQ score below 70, and significant impairment of adaptive behavior.

  • Savant syndrome: The possession of exceptional mental ability in one or more narrow areas, such as mental arithmetic, calendar calculation, art, or music, by a person of limited general intelligence.

    Cause of Intellectual Disability

  • Familial intellectual disability: Mild intellectual disability associated with homes that are intellectually, nutritionally, and emotionally impoverished.

  • Down Syndrome: A genetic disorder caused by the presence of an extra chromosome; results in an intellectual disability.

  • Fragile X syndrome: A genetic form of intellectual disability caused by a defect in the X chromosome.

  • Phenylketonuria (PKU): A genetic disease that allows phenylpyruvic acid to accumulate in the body.

  • Microcephaly: A disorder in which the head and brain are abnormally small.

  • Hydrocephaly: A buildup of cerebrospinal fluid within brain cavities.

  • Congenital hypothyroidism: Stunted growth and intellectual disability caused by an insufficient supply of thyroid hormone.

    9.4 Genetic and Environmental Contributions to Intelligence

    Hereditary Influences

    Twin Study

  • Twin study: A comparison of the characteristics of twins who were raised together or separated at birth; used to identify the relative impact of heredity and environment.

  • Fraternal twins: Twins conceived from two separate eggs.

  • Identical twins: Twins who develop from a single egg and so share the same genes.

    Studying the Science: Genes and Intelligence

    Intelligent Genes

  • Every individual gene contributes a small amount to a person’s intelligence

    How Genes Influence Intelligence

  • Genes may contribute to differences in:

    • Structure of the nervous system

    • Differences in the structure of the nervous system may cause changes to its functioning

    Effects on the Structure of the Nervous System

  • Executive functions by themselves do not equal the sum of our intelligence

    • More likely to be the g-factor, regulating and coordinating other parts of the brain

    Effects on the Functioning of the Nervous System

  • Reaction time: The amount of time that a person must look at a stimulus to make a correct judgment about it.

  • Speed of processing: The speed with which a person can mentally process information.

  • Neural intelligence: The innate speed and efficiency of a person’s brain and nervous system.

  • Experiential intelligence: Specialized knowledge and skills acquired through learning and experience.

  • Reflective intelligence: An ability to become aware of one’s own thinking habits.

  • Metacognitive skills: An ability to manage one’s own thinking and problem-solving efforts.

    Environmental Influences

    Adoption Studies

  • Studies on adopted children from the low socioeconomic status score on average 17.6 points higher than children who were not adopted.

    The Flynn Effect

  • The Flynn Effect- rapid rise in IQ in the last 50 years

    • Most likely caused by environmental factors and not genetics

  • These factors include

    • Modern society becoming more complex

    • Video games

    • Internet

  • Demand great abstract cognitive effort

    Formal Education

  • Early childhood education program: A program that provides stimulating intellectual experiences, typically for disadvantaged preschoolers.

    9.5 Thinking Ethically About Intelligence

  • Artificial intelligence (AI): Any artificial system (often a computer program) that is capable of human-like problem-solving or intelligent responding.

    9.6 Psychology and Your Skill Set: Emotional Intelligence

  • Emotional intelligence: The ability to perceive, use, understand, and manage emotions.

    The Four Elements of Emotional Intelligence

    • Perceiving emotions

    • Using emotions

    • Understanding emotions

    • Managing emotions

Chapter In Review

9.1 Defining Human Intelligence

9.1.1 Define what is meant by the g-factor in intelligence

Intelligence refers to the general capacity (or g-factor) to act purposefully, think rationally, and adapt to the environment. G-factor in turn, can be divided into fluid and crystallized intelligence.

9.1.2 Describe some of the challenges associated with defining intelligence

To be of any value, a psychological test must be reliable (give consistent results). A worthwhile test must also have validity, meaning that it measures what it claims to measure. Widely used intelligence tests are also objective (they give the same result when scored by different people) and standardized (the same procedures are always used in giving the test, and norms have been established so that scores can be interpreted).

9.2 Measuring Intelligence

9.2.1 Name and describe four characteristics of a good psychometric test

To be of any value, a psychological test must be reliable (give consistent results). A worthwhile test must also have validity, meaning that it measures what it claims to measure. Widely used intelligence tests are also objective (they give the same result when scored by different people) and standardized (the same procedures are always used in giving the test, and norms have been established so that scores can be interpreted).

9.2.2 Explain the need for “culture-fair” intelligence tests

Early tests of intelligence were biased against members of other cultural groups, members of minority groups, and people who were poor. The bias stemmed from questions that tested knowledge not common in these groups and a scoring system that assumed implicitly that European-American ways of thinking were more “intelligent” than those adopted by other groups.

9.2.3 Explain the difference between general intelligence (g) and aptitude tests

Special aptitude tests and multiple aptitude tests are used to assess a person’s capacities for learning various abilities (e.g., music; interpersonal skills). Aptitude tests measure a narrower range of abilities than general intelligence tests do. Many psychologists have suggested that Gardner’s “multiple intelligences” actually reflect a number of aptitudes rather than various forms of intelligence.

9.2.4 Name two well-established intelligence tests, and some of the main cognitive abilities that they test

One intelligence test is the Standford-Binet Intelligence Scales, Fifth Edition (SB5). A second major intelligence test is the Wechsler Adult Intelligence Scale—Fourth Edition (WAIS-IV). The children’s version of this test is the Wechsler Intelligence Scale for Children—Fifth Edition (WISC V). The SB5, WAIS-IV, and WISC-V measure both verbal and performance intelligence through tests of working memory, quantitative reasoning, and visual-spatial processing, for example.

9.2.5 Explain how the results of intelligence tests are expressed, and how the scores are distributed in the population

Intelligence is expressed as an intelligence quotient (IQ), defined as mental age divided by chronological age and then multiplied by 100. The distribution of IQ scores approximates a normal distribution. Modern IQ tests no longer calculate IQs directly. Instead, the final score reported by the test is a deviation IQ.

9.3 Intellectual Giftedness and Disability

9.3.1 Outline how gifted individuals are identified, and the outcomes that are typically associated with giftedness

People considered gifted tend to score above 130 on IQ tests. Intellectually gifted children often have difficulties in average classrooms and benefit from special accelerated programs. Research tends to support the ideas that gifted children are successful in their personal and professional lives, though the correlation is not perfect.

9.3.2 Outline how people with intellectual disabilities are identified, and the outcomes that are typically associated with this diagnosis

The term intellectually disabled is applied to those whose IQ falls below 70 and who lack various adaptive behaviors. Current classifications of intellectual disability are as follows: mild (50-55 to 70), moderate (35-40 to 50-55), severe (20-25 to 35-40), and profound (below 20-25). Chances for educational success are related to the degree of intellectual disability; however, those individuals who are able to demonstrate adaptive behaviors can make contributions to their communities and lead fulfilling lives.

9.3.3 Outline some of the causes of intellectual disability, and name some of the resulting conditions

Many cases of intellectual disability are thought to be the result of familial intellectual disability, a generally low level of education and intellectual stimulation in the home, poverty and poor nutrition. About 50 percent of the cases of intellectual disability are organic, being caused by birth injuries, fetal damage, metabolic disorders, or genetic abnormalities. The remaining cases are of undetermined cause. Six distinct forms of organic intellectual disability are Down syndrome, fragile X syndrome, phenylketonuria (PKU), microcephaly, hydrocephaly, and congenital hypothyroidism

9.4 Genetic and Environmental Contributions to Intelligence

9.4.1 Describe the general results of research investigating the role of genes in intelligence

Studies of twins demonstrate clearly that intelligence is partially determined by heredity. Heritability estimates tend to suggest that intelligence is approximately 50 percent heritable, but this is an average for the population as a whole. For any given pair of relatives, it may be higher or lower. Moreover, the importance of genes changes across the lifespan: they are less important earlier in life, but are more important contributors to intelligence as we move into adulthood. Newer studies suggest that there are likely hundreds of genes that contribute to intelligence, each one having a very small effect.

It is possible the genes code for a larger frontal cortex area in the brain, as this is the area that is most active when we carry out the type of tasks that are included on IQ tests. Another possibility is that genes code for the central nervous system (brain and spinal cord) that responds more quickly in intelligent people, or one that allows for better metacognitive thinking.

9.4.2 Describe the general results of research investigating the role of the environment in intelligence

Both adoption studies and the Flynn effect strongly suggest that the environment makes an important contributor to intelligence. Results of studies examining the effects of formation education (early childhood education, or ECE in particular) have been mixed. While early gains in intelligence associated with ECE are typically not sustained over long term, research does not suggest other advantages may be associated with ECE programs like Head Start. These include higher high school and college graduation rates, suggesting that even if school-based programming does not improve intelligence, it may affect other characteristics that allow children to persist in school.

9.5 Thinking Ethically About Intelligence

9.5.1 Identify two problems associated with the claim that genetic differences between groups explain group-based differences in intelligence

The first problem stems from the fact that what is currently known about the human genome is largely based on DNA of people of European descent, and there is evidence to suggest that there may be substantial differences in the genomes of different racial groups. It’s not clear, then, whether the genes traditionally associated with intelligence in European Americans will be the same for other groups, including African Americans. The second problem has to do with the fact that past research has relied on a very crude measure of race: identification using a limited number of options on a form, or obvious characteristics such as skin color. In reality, genetics are more closely aligned with ancestry, which reveals how one’s DNA may be influenced by many races over several generations. Using ancestry to obtain more precise measures of genetic inheritance going forward may be useful in shedding more light on whether genes have any role to play in group-based differences in IQ.

9.5.2 Define artificial intelligence, and explain some of the ethical concerns raised by its use

Artificial intelligence (AI) refers to any artificial system that can perform tasks that require intelligence when done by people. Two principal areas of AI research on particular human skills are expert systems and machine learning. Increased use of AI has raised ethical concerns about violations of people’s rights to privacy, and the possibility of racial profiling.

9.6 Psychology and Your Skill Set: Emotional Intelligence

9.6.1 Define emotional intelligence, including its four components

Emotional intelligence is the ability to recognize and understand emotions in ourselves and others, as well as the ability to manage those feelings effectively. Recognizing emotions in yourself and others can be helpful in terms of directing your behavior in ways that will promote your own growth and positive relationships with others. Similarly, being able to control your emotions appropriately has important consequences for health, achievement, and relationships. People who are “smart” emotionally are able to make use of each of the four components of emotional intelligence: perceiving emotions, using emotions, understanding emotions, and managing emotions.

9.6.2 Create a plan to respond in more emotionally intelligent ways in your everyday life

Skillfully managing the emotional responses of ourselves and others requires that we think carefully about the four components of emotional intelligence. We hope that after reading this section, you’ll be better able to think about how you can use these components to help when you need to handle difficult emotions in your everyday life.

SK

9: Intelligence

9.1 Defining Human Intelligence

  • Intelligence: Capacity for rational thought, purposeful action, and effective adaption.

  • G-factor: Measure of an individual’s overall intelligence as opposed to specific abilities.

  • Fluid intelligence: The ability to solve novel problems involving perceptual speed or rapid insight.

  • Crystallized intelligence: The ability to solve problems using already acquired knowledge.

    Challenges In Defining Intelligence

  • Aptitude: A capacity for learning certain abilities.

  • Multiple Intelligence: Howard Gardner’s theory that there are several specialized types of intellectual ability.

  • 9 Distinct Kinds of Intelligence:

    1. Linguistic (language abilities)

    2. Logical-mathematical (logic and number abilities)

    3. Visual (pictorial abilities)

    4. Musical (music abilities)

    5. Bodily-kinesthetic (physical abilities)

    6. Intrapersonal (self-knowledge)

    7. Interpersonal (social abilities)

    8. Naturalist (ability to understand the natural environment)

    9. Existential (ability to understand spirituality and existence)

  • Robert Sternberg: argued that an important component of intelligence is related to our ability to demonstrate skills that are practical or useful in the environment

    • People are “smart” in different way

  • If intelligence can refer to many things, term becomes somewhat meaningless and impossible to study

    • Intelligence defined as a g has some value because it correlates with many outcomes a culture views as important

    • Western view

    9.2 Measuring Intelligence

    Studying the Science: Characteristics of Good Intelligence Tests

  • Psychometric test: Any measurement of a person’s mental functions.

    Reliability

  • Reliability: The ability of a test to yield the same score, or nearly the same score, each time it is given to the same person.

    • Give to a large number of people and retest them later (test-retest)

    • Determine wheather scores on on half of the test items match scores on the other half (split-half reliability)

    • Compare scores on one version of the test to scores on the other (equivalent-forms reliability)

    Validity

  • Validity: The ability to measure what it purports to measure.

    • Compare test scores to actual performance on some other measure that is known to assess the construct you’re trying to measure (criterion validity)

    Human Diversity and Culture-Fair Intelligence Tests

  • Culture-fair test: A test (such as an intelligence test) designed to minimize the importance of skills and knowledge that may be more common in some cultures than in others.

    Objectivity and Standardization

  • Objective test: A test that gives the same score when different people correct it.

  • Test Standardization: Establishing standards for administering a test and interpreting scores.

    • Norm: An average score for a designated group of people.

    Ways to Measure Intelligence

    General Aptitude Tests

  • General Aptitude: Measures a narrower range of abilities than intelligence tests do

  • Special Aptitude test: A test to predict a person’s likelihood of succeeding in a particular area of work or skill.

  • Multiple Aptitude Test: A test that measures two or more aptitudes.

    • Tend to be more like an intelligence test

    • ACT, SAT, CQT

  • General intelligence test: A test that measures a wide variety of intellectual abilities.

    Stanford Binet Intelligence Test

  • Alfred Binet: Compared test scores of individual children to average scores for their age

    • Lewis Terman revised it for use in North America and renamed it

    • Current version - Stanford Binet Intelligence Scales, 5th Edition (SB5)

    • Measures general intelligence

  • SB5 measures five cognitive factors

    • Fluid Reasoning

      • Ability to reason in unfamiliar situations

    • Knowledge

      • Knowledge of a wide range of topics

    • Quantitative Reasoning - Problem-solving involving numbers

    • Visual-Spatial Processing

      • Reproducing patterns, and puzzles; copying geometric shapes

    • Working Memory

      • Use of short-term memory

    The Wechsler Tests

  • Wechsler Adult Intelligene Scale, 4th edition (WAIS-IV)

    • Similar to SB5

      • yields a single overall intelligence (g-factor)

  • Performance (nonverbal) intelligence: Intelligence measured by solving puzzles, assembling objects, completing pictures, and other nonverbal tasks.

  • Verbal intelligence: Intelligence measured by answering questions involving vocabulary, general information, arithmetic, and other languages- or symbol-oriented tasks.

    The Results of Intelligence Tests: Intelligence Quotients

  • Mental age: In intelligence testing, the average cognitive ability is displayed by people of a given age.

  • Intelligence quotient (IQ): Mental age divided by chronological age times 100.

  • Normal distribution: Bell-shaped curve of scores with a large number in the middle and very few on the high and low ends.

  • Deviation IQ: An IQ obtained statistically from a person’s relative standing in his or her age group—that is, how far above or below average the person’s score is relative to other scores.

    9.3 Intellectual Giftedness and Disability

    Identifying Gifted Children

  • Giftedness: The possession of either a high IQ or special talents or aptitudes.

    Identifying Individuals with Intellectual Disabilities

  • Intellectual disability (intellectual developmental disorder): The presence of a developmental disability, a formal IQ score below 70, and significant impairment of adaptive behavior.

  • Savant syndrome: The possession of exceptional mental ability in one or more narrow areas, such as mental arithmetic, calendar calculation, art, or music, by a person of limited general intelligence.

    Cause of Intellectual Disability

  • Familial intellectual disability: Mild intellectual disability associated with homes that are intellectually, nutritionally, and emotionally impoverished.

  • Down Syndrome: A genetic disorder caused by the presence of an extra chromosome; results in an intellectual disability.

  • Fragile X syndrome: A genetic form of intellectual disability caused by a defect in the X chromosome.

  • Phenylketonuria (PKU): A genetic disease that allows phenylpyruvic acid to accumulate in the body.

  • Microcephaly: A disorder in which the head and brain are abnormally small.

  • Hydrocephaly: A buildup of cerebrospinal fluid within brain cavities.

  • Congenital hypothyroidism: Stunted growth and intellectual disability caused by an insufficient supply of thyroid hormone.

    9.4 Genetic and Environmental Contributions to Intelligence

    Hereditary Influences

    Twin Study

  • Twin study: A comparison of the characteristics of twins who were raised together or separated at birth; used to identify the relative impact of heredity and environment.

  • Fraternal twins: Twins conceived from two separate eggs.

  • Identical twins: Twins who develop from a single egg and so share the same genes.

    Studying the Science: Genes and Intelligence

    Intelligent Genes

  • Every individual gene contributes a small amount to a person’s intelligence

    How Genes Influence Intelligence

  • Genes may contribute to differences in:

    • Structure of the nervous system

    • Differences in the structure of the nervous system may cause changes to its functioning

    Effects on the Structure of the Nervous System

  • Executive functions by themselves do not equal the sum of our intelligence

    • More likely to be the g-factor, regulating and coordinating other parts of the brain

    Effects on the Functioning of the Nervous System

  • Reaction time: The amount of time that a person must look at a stimulus to make a correct judgment about it.

  • Speed of processing: The speed with which a person can mentally process information.

  • Neural intelligence: The innate speed and efficiency of a person’s brain and nervous system.

  • Experiential intelligence: Specialized knowledge and skills acquired through learning and experience.

  • Reflective intelligence: An ability to become aware of one’s own thinking habits.

  • Metacognitive skills: An ability to manage one’s own thinking and problem-solving efforts.

    Environmental Influences

    Adoption Studies

  • Studies on adopted children from the low socioeconomic status score on average 17.6 points higher than children who were not adopted.

    The Flynn Effect

  • The Flynn Effect- rapid rise in IQ in the last 50 years

    • Most likely caused by environmental factors and not genetics

  • These factors include

    • Modern society becoming more complex

    • Video games

    • Internet

  • Demand great abstract cognitive effort

    Formal Education

  • Early childhood education program: A program that provides stimulating intellectual experiences, typically for disadvantaged preschoolers.

    9.5 Thinking Ethically About Intelligence

  • Artificial intelligence (AI): Any artificial system (often a computer program) that is capable of human-like problem-solving or intelligent responding.

    9.6 Psychology and Your Skill Set: Emotional Intelligence

  • Emotional intelligence: The ability to perceive, use, understand, and manage emotions.

    The Four Elements of Emotional Intelligence

    • Perceiving emotions

    • Using emotions

    • Understanding emotions

    • Managing emotions

Chapter In Review

9.1 Defining Human Intelligence

9.1.1 Define what is meant by the g-factor in intelligence

Intelligence refers to the general capacity (or g-factor) to act purposefully, think rationally, and adapt to the environment. G-factor in turn, can be divided into fluid and crystallized intelligence.

9.1.2 Describe some of the challenges associated with defining intelligence

To be of any value, a psychological test must be reliable (give consistent results). A worthwhile test must also have validity, meaning that it measures what it claims to measure. Widely used intelligence tests are also objective (they give the same result when scored by different people) and standardized (the same procedures are always used in giving the test, and norms have been established so that scores can be interpreted).

9.2 Measuring Intelligence

9.2.1 Name and describe four characteristics of a good psychometric test

To be of any value, a psychological test must be reliable (give consistent results). A worthwhile test must also have validity, meaning that it measures what it claims to measure. Widely used intelligence tests are also objective (they give the same result when scored by different people) and standardized (the same procedures are always used in giving the test, and norms have been established so that scores can be interpreted).

9.2.2 Explain the need for “culture-fair” intelligence tests

Early tests of intelligence were biased against members of other cultural groups, members of minority groups, and people who were poor. The bias stemmed from questions that tested knowledge not common in these groups and a scoring system that assumed implicitly that European-American ways of thinking were more “intelligent” than those adopted by other groups.

9.2.3 Explain the difference between general intelligence (g) and aptitude tests

Special aptitude tests and multiple aptitude tests are used to assess a person’s capacities for learning various abilities (e.g., music; interpersonal skills). Aptitude tests measure a narrower range of abilities than general intelligence tests do. Many psychologists have suggested that Gardner’s “multiple intelligences” actually reflect a number of aptitudes rather than various forms of intelligence.

9.2.4 Name two well-established intelligence tests, and some of the main cognitive abilities that they test

One intelligence test is the Standford-Binet Intelligence Scales, Fifth Edition (SB5). A second major intelligence test is the Wechsler Adult Intelligence Scale—Fourth Edition (WAIS-IV). The children’s version of this test is the Wechsler Intelligence Scale for Children—Fifth Edition (WISC V). The SB5, WAIS-IV, and WISC-V measure both verbal and performance intelligence through tests of working memory, quantitative reasoning, and visual-spatial processing, for example.

9.2.5 Explain how the results of intelligence tests are expressed, and how the scores are distributed in the population

Intelligence is expressed as an intelligence quotient (IQ), defined as mental age divided by chronological age and then multiplied by 100. The distribution of IQ scores approximates a normal distribution. Modern IQ tests no longer calculate IQs directly. Instead, the final score reported by the test is a deviation IQ.

9.3 Intellectual Giftedness and Disability

9.3.1 Outline how gifted individuals are identified, and the outcomes that are typically associated with giftedness

People considered gifted tend to score above 130 on IQ tests. Intellectually gifted children often have difficulties in average classrooms and benefit from special accelerated programs. Research tends to support the ideas that gifted children are successful in their personal and professional lives, though the correlation is not perfect.

9.3.2 Outline how people with intellectual disabilities are identified, and the outcomes that are typically associated with this diagnosis

The term intellectually disabled is applied to those whose IQ falls below 70 and who lack various adaptive behaviors. Current classifications of intellectual disability are as follows: mild (50-55 to 70), moderate (35-40 to 50-55), severe (20-25 to 35-40), and profound (below 20-25). Chances for educational success are related to the degree of intellectual disability; however, those individuals who are able to demonstrate adaptive behaviors can make contributions to their communities and lead fulfilling lives.

9.3.3 Outline some of the causes of intellectual disability, and name some of the resulting conditions

Many cases of intellectual disability are thought to be the result of familial intellectual disability, a generally low level of education and intellectual stimulation in the home, poverty and poor nutrition. About 50 percent of the cases of intellectual disability are organic, being caused by birth injuries, fetal damage, metabolic disorders, or genetic abnormalities. The remaining cases are of undetermined cause. Six distinct forms of organic intellectual disability are Down syndrome, fragile X syndrome, phenylketonuria (PKU), microcephaly, hydrocephaly, and congenital hypothyroidism

9.4 Genetic and Environmental Contributions to Intelligence

9.4.1 Describe the general results of research investigating the role of genes in intelligence

Studies of twins demonstrate clearly that intelligence is partially determined by heredity. Heritability estimates tend to suggest that intelligence is approximately 50 percent heritable, but this is an average for the population as a whole. For any given pair of relatives, it may be higher or lower. Moreover, the importance of genes changes across the lifespan: they are less important earlier in life, but are more important contributors to intelligence as we move into adulthood. Newer studies suggest that there are likely hundreds of genes that contribute to intelligence, each one having a very small effect.

It is possible the genes code for a larger frontal cortex area in the brain, as this is the area that is most active when we carry out the type of tasks that are included on IQ tests. Another possibility is that genes code for the central nervous system (brain and spinal cord) that responds more quickly in intelligent people, or one that allows for better metacognitive thinking.

9.4.2 Describe the general results of research investigating the role of the environment in intelligence

Both adoption studies and the Flynn effect strongly suggest that the environment makes an important contributor to intelligence. Results of studies examining the effects of formation education (early childhood education, or ECE in particular) have been mixed. While early gains in intelligence associated with ECE are typically not sustained over long term, research does not suggest other advantages may be associated with ECE programs like Head Start. These include higher high school and college graduation rates, suggesting that even if school-based programming does not improve intelligence, it may affect other characteristics that allow children to persist in school.

9.5 Thinking Ethically About Intelligence

9.5.1 Identify two problems associated with the claim that genetic differences between groups explain group-based differences in intelligence

The first problem stems from the fact that what is currently known about the human genome is largely based on DNA of people of European descent, and there is evidence to suggest that there may be substantial differences in the genomes of different racial groups. It’s not clear, then, whether the genes traditionally associated with intelligence in European Americans will be the same for other groups, including African Americans. The second problem has to do with the fact that past research has relied on a very crude measure of race: identification using a limited number of options on a form, or obvious characteristics such as skin color. In reality, genetics are more closely aligned with ancestry, which reveals how one’s DNA may be influenced by many races over several generations. Using ancestry to obtain more precise measures of genetic inheritance going forward may be useful in shedding more light on whether genes have any role to play in group-based differences in IQ.

9.5.2 Define artificial intelligence, and explain some of the ethical concerns raised by its use

Artificial intelligence (AI) refers to any artificial system that can perform tasks that require intelligence when done by people. Two principal areas of AI research on particular human skills are expert systems and machine learning. Increased use of AI has raised ethical concerns about violations of people’s rights to privacy, and the possibility of racial profiling.

9.6 Psychology and Your Skill Set: Emotional Intelligence

9.6.1 Define emotional intelligence, including its four components

Emotional intelligence is the ability to recognize and understand emotions in ourselves and others, as well as the ability to manage those feelings effectively. Recognizing emotions in yourself and others can be helpful in terms of directing your behavior in ways that will promote your own growth and positive relationships with others. Similarly, being able to control your emotions appropriately has important consequences for health, achievement, and relationships. People who are “smart” emotionally are able to make use of each of the four components of emotional intelligence: perceiving emotions, using emotions, understanding emotions, and managing emotions.

9.6.2 Create a plan to respond in more emotionally intelligent ways in your everyday life

Skillfully managing the emotional responses of ourselves and others requires that we think carefully about the four components of emotional intelligence. We hope that after reading this section, you’ll be better able to think about how you can use these components to help when you need to handle difficult emotions in your everyday life.