CHAPTER 12

More recently, the research psychologist Howard Gardner has suggested that

we speak of multiple intelligences in preference to global intelligence. Taking

this approach, one kind of intelligence may be more or less independent of

another kind of intelligence. An example of what Gardner means is kinesthetic

intelligence, the ability to comprehend the position of one's body in space. Such

intelligence is important in athletic performance and dancing.

(a) What kind of analysis did Thurstone make of intelligence tests?

(b) Gardner has suggested that we speak of in preference to global

intelligence.

Answers: (a) A factor analysis; (b) multiple intelligences.

It is possible to bring together the concept of a general ability with the concept

of specific abilities. The general factor, or g, is like the palm of a hand. It can

be small or large. The specific abilities are like the fingers of a hand, and they can

vary in length. This allows for many possibilities. Kurt has an unusually high level

of general intelligence, but finds it difficult to comprehend mathematical concepts.

Rita has an average level of general intelligence; however, she makes her living

as a sculptor, and she displays an unusually high level of ability in the area of

spatial visualization.

As you can see, it is difficult to pin intelligence down and say with any kind of

finality what it is. This in part is due to the fact that intelligence has the status of a

hypothetical construct. In science, a hypothetical construct is "constructed" by

the mind of the scientist in order to explain a set of facts. In physics, the concept

of an electromagnetic field is sometimes said to be such a construct. Science freely

employs hypothetical constructs. Intelligence as experienced by you is not, of

course, hypothetical. However, intelligence as measured by a psychologist with an

intelligence test is hypothetical. The intelligence has to be inferred from scores, and

140 PSYCHOLOGY

there is room for error whenever one makes an inference. (See the section on

validity and reliability on pages 145–147.)

(a) It is possible to bring together the concept of a general ability with the concept of

abilities.

(b) In scientific terms, intelligence has the status of a construct.

Answers: (a) specific; (b) hypothetical; (c) inferred.

The Stanford-Binet Intelligence Scale: Intelligent Is

as Intelligent Does

One of the first people to attempt to measure intelligence in an objective manner

was the English scientist Sir Francis Galton (1822–1911). Working somewhat over

one hundred years ago, he used the biometric method, meaning he tried to

measure intelligence directly by evaluating such physiological measures as strength

of grip and perceptual-motor speed. He found that there was little correlation

between these measures and intelligence. Discouraged, he discontinued his

research in this particular area of human behavior.

Only a few years after Galton abandoned the effort to measure intelligence,

Alfred Binet, director of the psychological laboratory at the Sorbonne in Paris,

was asked by France's Minister of Public Instruction to devise a way to detect subnormal

intelligence. The aim was to give extra instruction and assistance to children

with cognitive problems.

Binet, working in collaboration with the scientist Theodore Simon, published

the Binet-Simon Scale in 1905. This was the first modern intelligence test, and

today's tests still use its basic method—the performance method. In brief, the

subject is asked to demonstrate the existence of intelligence by giving answers to

questions. Correct answers reflect the existence of intelligence. Informally, the

Binet-Simon Scale was based on the premise that intelligence is as the intelligent

individual does.

(a) What method did Galton use in his unsuccessful attempt to measure intelligence?

(b) What method did Binet and Simon use in their successful attempt to measure intelligence?

Answers: (a) The biometric method; (b) The performance method.

Intelligence: In Pursuit of Rational Thought and Effective Action 141

The Binet-Simon Scale established a measure called mental age, or MA. Mental

age is determined by comparing one subject's score on the Binet-Simon Scale

with the scores of a group of subjects of the same age. Let's say that a group of nineyear-

old subjects is able, on average, to answer fifteen questions correctly on the

Scale. If seven-year-old Alice is able to answer fifteen questions correctly, her mental

age is nine even though her chronological age is seven. Binet and Simon expected

mental age to rise over time, and it does. In view of the fact that mental age is a

changeable number, this created a problem. (The way in which this problem was

solved with the concept of an intelligence quotient, or IQ, will be discussed later.)

The Binet-Simon Scale was translated into English by the Stanford psychologist

Lewis Terman. In 1916, only eleven years after Binet and Simon published

their test, the Stanford-Binet Intelligence Scale (SBIS) was published in the

United States. The SBIS became a popular way in which to measure intelligence,

and it is still used today in revised form.

One of the questions that interested Terman was: Do highly intelligent children

do, overall, better in life than children of normal intelligence? In order to answer

the question, Terman started a longitudinal study, a research project that measures

behavior over a span of time. In this case, the Stanford project, carried on after

Terman's death, continued for more than seventy years. The results are clear. On

the whole, highly intelligent children grew into highly intelligent adults. They

fared better in general in all aspects of life. They had better health, fewer divorces,

and better mental and emotional adjustment than subjects with average intelligence.

This result should not be surprising. If intelligence is to mean anything at all

as a concept, it must mean that it has value to the individual and society. As already

indicated in the definition of intelligence, the ability to think clearly and to function

effectively is part and parcel of what it means to be intelligent.

(a) What measure, abbreviated MA, is associated with the Binet-Simon Scale?

(b) Terman translated the Binet-Simon Scale into English and called it .

study?

Answers: (a) Mental age; (b) the Stanford-Binet Intelligence Scale (SBIS); (c) A longitudinal

study.

The Wechsler Scales: Comparing Verbal Intelligence

and Performance Intelligence

Working for a number of years as the chief psychologist for the Bellevue Psychiatric

Hospital in New York City, David Wechsler conducted a substantial amount

142 PSYCHOLOGY

of research on intelligence. His work culminated in a set of highly regarded intelligence

tests called collectively the Wechsler Scales. There are three individual

tests, and in revised editions they are still used today. The three tests are: (1) the

Wechsler Preschool and Primary Scale of Intelligence (WPPSI), (2) the

Wechsler Intelligence Scale for Children (WISC), and (3) the Wechsler

Adult Intelligence Scale (WAIS).

The Wechsler Scales have a clear-cut advantage over the Stanford-Binet Scale.

The Stanford-Binet measures general intelligence without regard to specific mental

abilities. The Wechsler Scales recognize that there are different kinds of intelligence.

Two in particular are emphasized: verbal intelligence and performance

intelligence. Verbal intelligence includes such abilities as word fluency, abstract

reasoning, and mathematical ability. Performance intelligence includes such

abilities as visualization, the perception of the relationship of parts to a whole, and

the capacity to relate well to other people. As a consequence, it is possible to

obtain two separate IQ scores, a verbal IQ and a performance IQ. The two IQ

scores can be combined for an overall IQ score.

(a) What does the abbreviation WAIS stand for?

(b) What two kinds of intelligence are clearly identified in the Wechsler Scales?

Answers: (a) Wechsler Adult Intelligence Scale; (b) Verbal intelligence and performance

intelligence.

The following description is based on the Wechsler Adult Intelligence Scale.

Not only is the Scale divided into two large areas, it is also subdivided into a set of

eleven subtests, six under the Verbal Scale and five under the Performance Scale.

Keep in mind that the word scale is used because sets of questions proceed from

easy to difficult. Evaluation is based on how high the subject can climb on the ladder

of psychological difficulty. Here is the breakdown:

The Verbal Scale: Each of the following tests consists of a group of questions

designed to assess a different area.

Information: level of general knowledge.

Comprehension: ability to understand questions and grasp concepts.

Arithmetic: capacity to grasp and employ mathematical concepts.

Similarities: ability to employ abstract thought.

Digit Span: tasks designed to measure attention span.

Vocabulary: grasp of the meaning of words.

The Performance Scale: Each of the following tests is a set of tasks designed to

assess a different area.

Intelligence: In Pursuit of Rational Thought and Effective Action 143

Digit Symbol: mental flexibility and ability to employ arbitrary symbols.

Picture Completion: ability to detect the missing parts of an organized whole

(i.e., a Gestalt).

Block Design: ability to relate a printed pattern to a physical construction.

Picture Arrangement: ability to comprehend the "before and after" aspect of

time. Also useful in evaluating the subject's level of social intelligence.

Object Assembly: ability to place parts in a correct relationship to a whole.

Under optimal conditions, a trained psychologist administers the Wechsler

Adult Intelligence Scale to a given to a subject on an individual basis. The results

of the test, when properly scored and evaluated, provide a clear picture of the

individual's level of cognitive functioning at both a general level and at the level

of specific mental abilities.

(a) TheWechsler Adult Intelligence Scale consists of a set of how many subtests?

(b) What subtest in the Verbal Scale is designed to assess the subject's ability to understand

questions and grasp concepts?

of words?

(d) What subtest in the Performance Scale is designed to assess the subject's mental flexibility

and ability to employ arbitrary symbols?

(e) What subtest in the Performance Scale is designed to assess the subject's ability to relate

a printed pattern to a physical construction?

Answers: (a) Eleven; (b) Comprehension; (c)Vocabulary; (d) Digit Symbol; (e) Block Design.

The Concept of an Intelligence Quotient: Following

the Bell-Shaped Curve

As already noted, the concept of mental age (MA) is of limited value because it is

unstable. As one's chronological age (CA) increases, so does one's mental age.

Consequently, a German psychologist named William Stern suggested that a ratio

based on the comparison of mental age with chronological age would tend to be

relatively stable. Stern proposed the following formula:

IQ = _

× 100

IQ stands for intelligence quotient. The IQ is a quotient because it is the

result of a division process.

144 PSYCHOLOGY

MA stands for mental age.

CA stands for chronological age

CA is divided into MA and multiplied by 100. Stern suggested the multiplication

step be employed with the aim of getting rid of decimals in the final quotient. For

example, instead of an IQ being reported as 1.15, it is reported as 115.

Let's say that Irwin has a CA of 9 and an MA of 9; 9 ÷ 9 = 1. Multiply 1 by

100 and the product is 100. Consequently Irwin's IQ score is 100. This is a normal,

or average, IQ. This makes sense in view of the fact that the average child of

9 years old will also have a mental age of 9. Let's say Irwin is tested again when he

is 11 years old. His MA is now 11. A CA of 11 divided into an MA of 11 is 1. So

Irwin's IQ is still 100.

Let's say that Lana has a CA of 8 and an MA of 10; 10 ÷ 8 = 1.25. Multiply by

100 and Lana's IQ score is 125, above normal.

Let's say that Jeffrey has a CA of 9 and an MA of 8; 8 ÷ 9 = .89. Multiply by

100 and Jeffrey's IQ score is 89, below normal.

(a) Stern suggested that a based on the comparison of mental age with

chronological age would tend to be relatively .

(b) What is the formula for IQ?

Answers: (a) ratio; stable; (b) IQ = _

× 100.

Research has demonstrated that the IQ score is a random variable, meaning a

variable distributed according to the laws of chance. This means that in a large

sample of scores the scores will tend to take on a bell-shaped distribution. This

distribution, well studied by statisticians, goes by three names: (1) the bell-shaped

curve, (2) the normal curve, and (3) the Gaussian curve. The third name is in

honor of the nineteenth-century German mathematician Karl Friedrich Gauss,

who first studied the curve's properties. Applying the curve to IQ scores, seven

categories emerge. These are summarized in the accompanying table.

IQ scores

70 80 90 100 110 120 130

A large sample of IQ scores tends to display a bell-shaped distribution.

Intelligence: In Pursuit of Rational Thought and Effective Action 145

(a) Research has demonstrated that the IQ score is a variable.

(b) What are the two other names of the bell-shaped curve?

classification?

(d) What percent of subjects fall within an IQ score of 130 or above, the Very Superior classification?

Answers: (a) random; (b) The normal curve and the Gaussian curve; (c) 50 percent;

(d) 2.2 percent.

Validity and Reliability: Two Big Problems in Any Kind

of Testing

Let's say that a confused auto mechanic gets certain important wires crossed on

the display panel in your car. You are driving merrily along and your gas gauge

reads "Full." However, soon you are forced to pull over to the side of the road.

Your car has overheated and it's also out of gas. What has gone wrong? The gas

gauge, unfortunately, was giving information on temperature, not fuel in the tank.

Under these conditions, the gas gauge had lost its validity as a measuring instrument.

Interestingly, it was functioning in a reliable manner. It was reliably giving

you the wrong information! As you can see, validity and reliability, although

related, are not the same thing.

Validity and reliability are important aspects of any kind of measurement and

testing. Intelligence tests are—like gauges, clocks, and rulers—measuring instruments.

Consequently, before they can be used to measure intelligence with any

degree of confidence, their validity and reliability must be assessed.

A valid test is one that measures what it is supposed to measure. If an intelligence

test really does in fact measure intelligence, then it is valid. But how can one

ascertain that the test is valid? Just because the questions in a test seem valid does

IQ Categories

IQ Classification Percent

130 and above Very Superior 2.2

120–129 Superior 6.7

110–119 Bright Normal 16.1

90–109 Normal (or Average) 50.0

80–89 Dull Normal 16.1

70–79 Borderline 6.7

69 and below Cognitively Deficient 2.2

146 PSYCHOLOGY

not mean they actually are. This kind of validity is called face validity, meaning

that the questions have a surface appearance of validity.

(a) Like gauges, clocks, and rulers, intelligence tests are what kind of instruments?

(b) A test is one that measures what it is supposed to measure.

Answers: (a) Measuring instruments; (b) valid.

In order to evaluate the validity of an intelligence test, it is necessary to compare

test scores with an outside criterion. An outside criterion is a measurement

instrument that is independent of the intelligence test being evaluated. A useful

outside criterion is grade point average. If intelligence means anything at all, then

students with high IQ scores should have high grade point averages. In research,

this relationship is evaluated with a statistical tool called the correlation coefficient,

a measure of the magnitude of the relationship between two variables (see

chapter 2). If the correlation between IQ scores and grade point average is high,

then it seems reasonable to conclude that the intelligence test in question has

validity. The higher the correlation coefficient, the more valid the test is considered

to be.

Other outside criteria that can be used are teacher ratings and evaluations

made by parents.

(a) An criterion is a measurement instrument that is independent of the

intelligence test being evaluated.

(b) What statistical tool is used to evaluate the magnitude of the relationship between two

variables?

Answers: (a) outside; (b) The correlation coefficient.

A reliable test is one that gives stable, repeatable results. Let's say that you

use a certain thermometer to take the temperature of family members when an

illness is suspected. In most cases, the thermometer will be reliable. You can

depend on it.

An intelligence test has to be carefully assessed for reliability. This is also

accomplished with the use of the correlation coefficient. Let's say that a 100-

question test is split into two versions, Form A and Form B. The original 100

questions are randomly assigned to two forms. Form A has 50 questions. Form

B has 50 questions. The two tests are administered, for example, one week apart

to the same group of children. If Sheila obtains an IQ score of 119 on Form A,

she should obtain a score close to 119 on Form B. However, if she obtains 119

on Form A and 87 on Form B, the reliability of the test is in question. Com-

Intelligence: In Pursuit of Rational Thought and Effective Action 147

paring paired scores for each child in the group, a high score on Form A should

predict a high score on Form B. And a low score on Form A should predict a

low score on Form B. If these predictions aren't obtained, then the test is not

reliable.

A test is one that gives stable, repeatable results.

Answer: reliable.

The two related factors of validity and reliability generate four possibilities

for any kind of measuring instrument. The instrument may be (1) neither valid

nor reliable, (2) valid, but not reliable, (3) reliable, but not valid, (4) both valid

and reliable. This fourth happy circumstance is the one we usually associate

with rulers, clocks, and thermometers. These are the primary measuring instruments

of physics. They are some of the reasons why it has such a high status as

a science.

In psychology, both personality tests and intelligence tests are forced to deal

with the mutual problems of validity and reliability. Fortunately, with the use of

the correlation coefficient applied to large sets of scores, a reasonable level of

validity and reliability can be obtained. The Stanford-Binet Intelligence Scale and

the Wechsler Scales have been subjected to a substantial amount of scrutiny and

evaluation. On the whole, they are considered to be both valid and reliable measuring

instruments.

The two related factors of validity and reliability generated how many possibilities for any

kind of measuring instrument?

Answer: Four.

The Interaction of Heredity and Environment: How They

Exert Joint Effects

What is the primary determinant of intelligence? Is it heredity? Is it environment?

Or, is it possible that the best answer can't be given in either-or terms?

The topic under discussion in this section is sometimes called the naturenurture

controversy, and it has a long history in philosophy, biology, and psychology.

Nature refers to heredity; the primary characteristic of nature, or

heredity, is the potential to reach a given level of intelligence. Nurture, on the

other hand, refers to environment; the primary characteristic of nurture, or environment,

is its capacity to bring forth, in the case of intelligence, the maximum

cognitive potential that an individual has. Or, conversely, environment has the

capacity to inhibit and restrict that potential.

148 PSYCHOLOGY

(a) The word refers to heredity.

(b) The primary characteristic of heredity is the to reach a given level of intelligence.

Answers: (a) nature; (b) potential; (c) nurture.

Let's say that a mother and a father insist that their two sons have had the

"same" environment. Both were loved, ate the same kind of food, and received

the same kind of cognitive stimulation. Now thirty-year-old Kendrick has a

Ph.D. in physics. His brother, twenty-seven-year-old Mark, is an insurance broker.

The parents say that since early childhood Kendrick has had a brilliant,

unusual mind. Mark has always appeared to have normal intelligence. The parents

are convinced that the difference in the cognitive functioning of their two

sons is intrinsic, something that is built in to the two individuals. This general

line of reasoning tends to support the importance of heredity. It can be argued

that the individual differences in the two brothers have a genetic basis. Although

siblings do have many genes in common, there is still plenty of room for unique

genetic patterns.

A strong advocate of the importance of environment in shaping intelligence is

likely to point out that, strictly speaking, the two brothers didn't have the same

environment. That is why the word same appeared with quotes around it in the

above paragraph. It is possible to suggest, as the pioneer psychotherapist Alfred

Adler did, that a first child and a second child have, by definition, different environments.

The first child lives for a time as an only child. The second child always

lives in a world with a sibling. It is possible to hypothesize that a first child often

receives, for a time, more attention and affection than a second child is likely to

receive.

In spite of the Adlerian birth-order argument, when individuals are raised in

the same home and with the same parents, variations in intelligence tend to support

the genetic hypothesis.

(a) Individual differences in intelligence in siblings who have had highly similar environments

are likely to have what kind of a basis?

(b) According to Adler, a first child and a second child have, by definition, environments.

Answers: (a) A genetic basis; (b) different.

The fictional tale Tarzan of the Apes is a reflection of the genetic hypothesis.

Tarzan, after all, develops the intelligence of a human being even though he's

raised in an environment of ape intelligence. However, as indicated, Tarzan is a

Intelligence: In Pursuit of Rational Thought and Effective Action 149

fictional character. Children raised by animals or in deprived circumstances are

called feral children. When such children are discovered, they seldom display

adequate cognitive functioning. A famous case is that of the wild boy of the forest

of Aveyron in France. Discovered at the age of seven and studied by the

nineteenth-century physician Jean-Marc-Gaspard Itard, the boy, given the name

Victor, never did attain normal intelligence. Similar studies of feral children

support Itard's research findings. So, in spite of the story of Tarzan, it appears

that early experiences have to be within the context of a human social environment

in order to bring out the individual's genetic potentiality.

A substantial body of research suggests that a stimulus-rich environment

will make a large difference in measurable intelligence. A stimulus-rich environment,

for human beings, is one that provides a great deal of affection along with

mental stimulation of a verbal and symbolical nature. A child who is played with

spontaneously, exposed to the printed word, provided with challenging toys, and

encouraged to express himself or herself is likely to automatically maximize his or

her genetic potentiality.

(a) The fictional tale of Tarzan of the Apes reflects what hypothesis as an explanation of

intelligence?

(b) Children raised by animals or in deprived circumstances are called children.

affection along with mental stimulation of a verbal and symbolical nature.

Answers: (a) The genetic hypothesis; (b) feral; (c) stimulus-rich.

We can see that in a best-case scenario the function of the environmental factor

is to elicit, or bring forth, the genetic potential of the child. It can't put that

potential there, but it can help make it reach its highest and best level.

The concept of an interaction, a formal mathematical concept, is useful at this

point. An interaction occurs when two (or more) variables affect each other in a

complex way. In contrast, the relationship between two variables is said to be additive

when they don't affect each other's value. For example, 3 × 3 = 9. The relationship

between the numbers is interactive because the whole (the product) is

more than the sum of its parts. On the other hand, 3 + 3 = 6. In this case the relationship

between the numbers is additive because the whole (the sum) is the sum

of its parts.

Loosely speaking, a kind of "magic" occurs when there is an interaction.

Something is produced that is not "in" the original variables. So it is with intelligence.

It is very difficult to say, when there is an interaction, that one factor is of

greater importance than another factor. It is the joint effects of the two factors

working together that produce a result. In the case of intelligence, the nature-

150 PSYCHOLOGY

nurture controversy is something of a false issue. The correct formula for understanding

intelligence is this one:

Heredity ¥ Environment = Intelligence

(The multiplication sign is used to symbolize an interaction.)

The answer to the heredity-environment debate should not be given in

either-or terms. The answer should be given in both-and terms. Both heredity and

environment, interacting, play important roles in determining intelligence.

(a) An occurs when two (or more) variables affect each other in a complex

way.

(b) What is the correct formula for understanding intelligence?

Answers: (a) interaction; (b) Heredity × Environment = Intelligence.

SELF-TEST

1. One of the following is not a primary characteristic of intelligence:

a. The ability to think clearly

b. Eccentric thinking

c. Convergent thinking

d. Functioning effectively in the environment

2. In behavioral science, intelligence has the status of

a. a hypothetical construct

b. a psychological atom

c. a transcendental force

d. an interim operant

3. What method was employed by Binet and Simon to measure intelligence?

a. The biometric method

b. The perceptual-motor method

c. The performance method

d. The physiological method

4. A research project that measures behavior over a span of time is called a

a. discontinuity study

b. gradient study

c. longitudinal study

d. continuity study

Intelligence: In Pursuit of Rational Thought and Effective Action 151

5. Which of the following is the correct formula for the intelligence quotient (IQ)?

a. IQ = MA × CA + 100

b. IQ = CA + MA × 3.14

c. IQ = MA + MA/100

d. IQ = MA/CA × 100

6. An IQ score in the range 110 to 119 is associated with what classification?

a. Very Superior

b. Superior

c. Bright Normal

d. Normal (or Average)

7. A test that measures what it is supposed to measure is said to be

a. consistent

b. reliable

c. valid

d. congruent

8. A test that gives stable, repeatable results is said to be

a. authentic

b. reliable

c. valid

d. systematic

9. The inborn potential to reach a given level of intelligence is associated primarily

with which of the following?

a. Nature

b. Nurture

c. Environment

d. Reinforcement

10. The correct formula for understanding intelligence is which of the following?

a. Heredity × Environment = Intelligence

b. Heredity + Environment = Intelligence

c. Nature × Heredity = Intelligence

d. Nurture × Environment = Intelligence

ANSWERS TO THE SELF-TEST

1-b 2-a 3-c 4-c 5-d 6-c 7-c 8-b 9-a 10-a

152 PSYCHOLOGY

ANSWERS TO THE TRUE-OR-FALSE PREVIEW QUIZ

1. True.

2. True.

3. False. There is an information subtest in the Wechsler Intelligence Scales.

4. False. An intelligence quotient (IQ) score of 100 is associated with normal, or average,

intelligence.

5. True.

KEY TERMS

bell-shaped curve (normal curve, or

Gaussian curve)

Binet-Simon Scale

biometric method

chronological age (or CA)

convergent thinking

correlation coefficient

environment

face validity

factor analysis

feral children

general factor (or g)

hypothetical construct

intelligence

intelligence quotient (or IQ)

interaction

kinesthetic intelligence

longitudinal study

mental age (or MA)

multiple intelligences

nature

nature-nurture controversy

nurture

outside criterion

performance intelligence

performance method

potential

reliable test

social environment

specific mental abilities (or s)

Stanford-Binet Intelligence Scale (SBIS)

stimulus-rich environment

valid test

verbal intelligence

Wechsler Adult Intelligence Scale (WAIS)

Wechsler Intelligence Scale for Children

(WISC)

Wechsler Preschool and Primary Scale of

Intelligence (WPPSI)

Wechsler Scales

11Developmental Psychology:

How Children Become

Adults

153

PREVIEW QUIZ

True or False

1. T F If a fertilized egg contains an XX chromosome pattern, the resulting

infant will be a female.

2. T F According to Freud, the five stages of psychosexual development are:

(1) oral, (2) anal, (3) phallic, (4) latency, and (5) genital.

3. T F In psychosocial development, the stage of identity versus role confusion

is associated with old age.

4. T F Cognitive development focuses primarily on the emotional adjustment

of the child.

5. T F An authoritarian parent tends to be easygoing, overly agreeable,

detached, and easily manipulated by the child or adolescent.

(Answers can be found on page 172.)

The previous chapter examined the concept of intelligence. The ways in

which children develop the kinds of mental skills associated with reasoning

and human intelligence are among the principal concerns of developmental

psychology.

OBJECTIVES

After completing this chapter, you will be able to

• define developmental psychology;

• describe fetal development;

• explain Freud's theory of psychosexual development;

• specify key features of Erikson's theory of psychosocial development;

• identify the four stages in Piaget's theory of cognitive development;

• identify the three levels in Kohlberg's theory of moral development;

• describe the two basic dimensions of parental style.

A familiar proverb states, "As the twig is bent, so grows the tree." Meant to

apply as a metaphor to the raising of children, this saying contains within it an

entire justification for the study of developmental psychology. Every adult was

once a child, and the adult was shaped and formed by experiences during childhood.

Psychologists as far apart in many of their assumptions and conclusions as

Sigmund Freud and John Watson subscribed to the general view that in order to

understand adult behavior it is necessary to study child behavior.

The contemporary approach to developmental psychology expands the concept

of development well past childhood and adolescence. There are also developmental

stages associated with adulthood. This will be evident when Erik

Erikson's theory of development is presented later in this chapter.

Developmental psychology is the study of the growth and maturation of

the individual over an extended span of time. Child psychology is a subset of

developmental psychology. It concerns itself primarily with the study of the

individual from birth to the beginning of adolescence (usually around the age of

twelve or thirteen). Adolescent psychology is also a subset of developmental

psychology. It concerns itself primarily with the study of the individual from the

beginning of adolescence to its end (usually around the age of eighteen). Sometimes

child psychology refers loosely to both child and adolescent psychology.

(a) Developmental psychology is the study of the and of the

individual over time.

(b) Child psychology is a of developmental psychology.

Answers: (a) growth; maturation; (b) subset; (c) subset.

154 PSYCHOLOGY

Biological Aspects of Development: From Fertilized Egg

to Infant

Freud said, "Biology is destiny." Although Freud is usually thought of as a psychologist,

not a biologist, his early academic love was the study of biology. He

was trained as a biologist before he became a medical doctor. Freud's statement

recognizes that, although learning and experience shape behavior, much of our

behavior is based on a foundation of genetic givens. For example, if a fertilized

egg contains an XX chromosome pattern, the individual will become a female.

If the fertilized egg contains an XY pattern, the individual will become a male.

The fact that one is a female or a male will be an important determining factor

in countless behaviors from birth to death. For a second example, let's say that

a fertilized egg contains three chromosomes where normally there is a twentyfirst

pair of chromosomes. This is a chromosomal anomaly known as trisomy

21. The individual will suffer from Down's syndrome, a pattern characterized

by mental retardation and poor health. Freud's view that biology is destiny has

much to recommend it. (A chromosomal anomaly is an abnormal chromosome

pattern.)

(a) Freud said, "Biology is ."

(b) If a fertilized egg contains an XX chromosome pattern, the individual will

become a .

in the individual?

Answers: (a) destiny; (b) female; (c) Down's syndrome.

The individual begins when a given sperm and a given ovum unite. Provided

by the father, the sperm, or more completely spermatozoon, is a highly mobile

cell with a tail. Provided by the mother, the ovum is a single egg cell. Both the

sperm and the ovum contain twenty-three single chromosomes. When the egg is

fertilized, there will be twenty-three pairs of chromosomes. Meiosis is the process

that reduces pairs of chromosomes to the individual chromosomes found in either

the sperm or the ovum. Mitosis, on the other hand, is the process that allows a

cell to reproduce itself. This process starts with twenty-three pairs of chromosomes,

and all twenty-three pairs are replicated. It is mitosis that makes possible

the growth of the individual from one cell, the fertilized egg, to billions of cells.

(a) A more complete name for the sperm is the .

(b) Provided by the mother, the is a single egg cell.

Developmental Psychology: How Children Become Adults 155

(d) What is the process that reduces pairs of chromosomes to individual chromosomes?

(e) What is the process that allows a cell to reproduce itself?

Answers: (a) spermatozoon; (b) ovum; (c) single; (d) Meiosis; (e) Mitosis.

A chromosome is a rodlike structure that contains genes. A chromosome is

so named because it is capable of picking up a dye, making the structure visible

under a microscope. Chromo refers to color, and soma refers to body. Thus a chromosome

is a "colored body."

A gene is the basic unit of heredity. It is made up of strands of deoxyribonucleic

acid (DNA), a complex organic molecule with the unique ability to

replicate itself. It is the genes that do all of the active work associated with hereditary

influence. The relationship of a chromosome to a group of genes is similar to

the relationship of a ship to its crew. The chromosome is the ship. The genes are

the members of the crew.

(a) A rod-like structure containing genes is called what?

(b) A gene is the basic unit of .

Answers: (a) A chromosome; (b) heredity; (c) deoxyribonucleic acid.

There are four stages associated with conception and birth: (1) zygote, (2)

embryo, (3) fetus, and (4) neonate. When a sperm and an ovum unite to form a

fertilized egg, the new being is called a zygote. The stage of the zygote lasts for

one week. During this stage the zygote develops rapidly from a single cell to a

large group of cells. A zygote may be imagined as a ball of cells without differentiation.

From one week to seven weeks, the new being is called an embryo. As the

cells continue to divide and replicate themselves, some differentiation begins to

take place. Three basic embryonic layers emerge: (1) ectoderm, (2) mesoderm,

and (3) endoderm. The ectoderm is the outer layer of cells, and it will become

the sense organs, skin, and nervous system. The mesoderm is the middle layer of

cells, and it will become the heart, bones, and muscles. The endoderm is the

internal layer of cells, and it will become the stomach, intestines, and lungs.

(a) When a sperm and an ovum unite to form a fertilized egg the new being is

called a .

(b) From one week to seven weeks, the new being is called an .

156 PSYCHOLOGY

(d) The is the middle layer of embryonic cells.

(e) The is the internal layer of embryonic cells.

Answers: (a) zygote; (b) embryo; (c) ectoderm; (d) mesoderm; (e) endoderm.

From seven weeks to birth, the new being is called a fetus. Fetal development

is rich and complex. The cells continue to divide, and they become specialized in

their structures and functions. Brain cells (neurons), skin cells, hair cells, fat cells,

and many other kinds of cells form. The head, limbs, fingers and toes, and other

features of the body appear. In the typical case, the stage of the fetus lasts a little

over seven months, making the total time from conception to birth about nine

months.

At birth the new being is called a neonate. Neo means "new." And nate means

"birth." Thus the word neonate simply means "newborn." If the neonate loses

weight after birth, then he or she is not referred to as an infant until birth weight

has been regained. The word infant is from Latin roots meaning "without

speech."

(a) From seven weeks to birth, the new being is called a .

(b) At birth the new being is called a .

Answers: (a) fetus; (b) neonate; (c) infant.

Freud's Theory of Psychosexual Development:

From the Oral to the Genital Stage

The infant is on the threshold of continuing biological and psychological development.

Our principal concern in this and future sections of this chapter is with

psychological development. Freud's theory of development has been highly influential.

First proposed about eighty years ago, it has had a large impact on the way

in which both psychologists and parents have thought about sexual development

in children. It has also influenced child-rearing practices.

According to Freud, there are five stages in psychosexual development. Psychosexual

development refers to the development of a sexual identity, attitudes

toward sexual behavior, and emotional reactions to sexual stimuli. Sexual development,

in Freud's view, is much more than biological. Identity, attitudes, and

emotional reactions are psychological in nature. That is why Freud used the term

psychosexual instead of simply sexual to refer to the kind of development he wanted

to study.

Developmental Psychology: How Children Become Adults 157

The five stages of psychosexual development are: (1) oral, (2) anal, (3) phallic,

(4) latency, and (5) genital. In order to appreciate Freud's theory, it is necessary to

introduce a concept he employed called libido. Libido is thought of as psychosexual

energy, and Freud hypothesized that it is invested in different zones of the

body during the various stages of psychosexual development. These zones, or

areas, of the body are called the erogenous zones, and they are associated with

sexual pleasure. The principal erogenous zones are the oral, anal, and genital areas

of the body.

(a) The term refers to the development of a sexual identity, attitudes toward

sexual behavior, and emotional reactions to sexual stimuli.

(b) Freud thought of as psychosexual energy.

Answers: (a) psychosexual development; (b) libido; (c) erogenous.

The oral stage lasts for about two years (infancy). During this stage the infant

obtains a substantial amount of pleasure from sucking, biting, chewing, and so

forth.

The anal stage lasts for about one or two years (the stage of the toddler).

During the anal stage the toddler obtains a substantial amount of pleasure from, at

times, withholding fecal matter and, at other times, expelling it. Note that this

stage coincides with the time at which most children are toilet trained.

The phallic stage lasts for about three years (the stage of the preschooler).

During the phallic stage the preschooler, according to Freud, obtains a substantial

amount of pleasure from self-stimulation of the phallus. The phallus in the

male is the penis. In the female it is the clitoris. The phallic stage ends at about

the age of six.

(a) What psychosexual stage is associated with infancy?

(b) What psychosexual stage coincides with the time at which most children are toilet

trained?

Answers: (a) The oral stage; (b) The anal stage; (c) penis; clitoris.

The latency stage lasts for about six years. It begins at age six or seven and

ends at age twelve or thirteen. In effect, it ends when puberty begins. The libido

has migrated from the oral to the anal to the phallic zone. Now it goes underground

and becomes, to surface appearance, dormant. The libido goes under-

158 PSYCHOLOGY

ground not because of a lack of biological maturation, but because of psychological

conflict. Freud suggested that the child has a certain amount of dawning sexual

desire and tends to make the parent of the opposite sex the focus of this desire.

However, due to moral development, guilt sets in and the libido goes into hiding.

It is repressed to an unconscious level.

The emotional conflict associated with the child's forbidden wish to seek sexual

expression with a parent is called the Oedipus complex. Freud was inspired

to coin this term from his familiarity with the Greek tragedy Oedipus Rex (i.e.,

"Oedipus, the King") written by the dramatist Sophocles around 400 B.C. In the

play, Oedipus inadvertently kills his own father and unknowingly marries his own

mother. Writing in German in Austria, Freud used the term Oedipus complex to

refer to either males or females. Later authors, writing in the United States, sometimes

use the term Oedipus complex to refer to males and Electra complex to

refer to females. (Electra is also a Greek play. Written by the dramatist Euripides,

also around 400 B.C., it bears some resemblance to Oedipus Rex.)

(a) According to Freud, during the latency stage the libido is repressed to an

level.

(b) What name did Freud give to the emotional conflict associated with a child's forbidden

sexual wish during the latency stage?

conflict during the latency stage?

Answers: (a) unconscious; (b) The Oedipus complex; (c) The Electra complex.

The genital stage begins at twelve or thirteen and continues throughout

adulthood. With puberty, biological maturation can no longer be denied. The

repression lifts and the individual becomes intensely conscious of sexual interest.

Libido makes a final shift from the phallus to a more general interest in the opposite

sex. In normal development, the individual transfers sexual interest away from

the parent and toward potential partners who are not members of the family.

Freud's outline suggests that much can go wrong with sexual development.

There can be too much excitation and arousal associated with one of the stages. Or,

conversely, there can be too much inhibition, punishment, or emotional injury associated

with one of the stages. Freud indicated that either too much excitation or too

much inhibition can induce a fixation of libido, meaning the libido is to some

extent "stuck" in one particular erogenous zone. According to Freud, such fixations

may play a role in various problems and maladaptive behaviors, including overeating,

constipation, pedophilia, exhibitionism, fetishism, and sexual dysfunctions.

Freud's theory is, as are all theories, a set of concepts, not a set of facts. Freud's

theory has received its share of criticism. For example, research suggests that

although self-stimulation of the phallus is relatively common in children, it is not,

Developmental Psychology: How Children Become Adults 159

as Freud thought, a behavior pattern demonstrated by almost all children. The

psychoanalyst Karen Horney, one of Freud's advocates, rejected the biological

sexuality of the Oedipus complex. Instead, Horney suggested that, for example, a

male child is often jealous of the position of power and importance the father has

with the mother. The male child has a forbidden wish to take the father's place,

not so much as a sexual rival, but as a psychological one.

(a) During what stage does the libido make a final shift from the phallus to a more general

interest in the opposite sex?

(b) Freud indicated that either too much excitation or too much inhibition can induce a

of libido in one particular zone.

Oedipus complex.

Answers: (a) The genital stage; (b) fixation; erogenous zone; (c) biological sexuality.

Erikson's Theory of Psychosocial Development: From Trust

to Integrity

Erik Erikson (1902–1994) was personally trained by Freud, and maintained

respect for Freud's theory. However, he expanded Freud's concept of psychosexual

development to include psychosocial development. Psychosocial development

refers to the characteristic ways in which the individual learns to respond to

other people. The term social world is often used to refer to the constellation of

other human beings in our environment—parents, siblings, teachers, friends,

sweethearts and lovers, husbands and wives, and coworkers. This is the world

addressed by Erikson's theory.

According to Erikson, there are eight stages in psychosocial development:

(1) trust versus mistrust, (2) autonomy versus shame and guilt, (3) initiative versus

guilt, (4) industry versus inferiority, (5) identity versus role confusion, (6) intimacy

versus isolation, (7) generativity versus self-absorption, and (8) integrity versus

despair.

In each stage the first attribute mentioned is a positive, or desirable, personality

trait. The second attribute is a negative, or undesirable, personality trait. Trust,

for example, is positive. Mistrust is negative. At each stage of development, the

individual is challenged by life to form the positive trait.

(a) The characteristic ways in which the individual learns to respond to other people is associated

with what kind of development?

(b) The term is often used to refer to the constellation of other human beings

in our environment.

160 PSYCHOLOGY

desirable, personality trait.

Answers: (a) Psychosocial development; (b) social world; (c) positive.

Trust versus mistrust is associated with infancy (birth to two years old). An

infant with a sense of trust tends to thrive and expects good things to happen.

Conversely, an infant with a sense of mistrust sometimes displays a failure to thrive

syndrome. A lack of interest in the surrounding world and poor health, associated

with mistrust, are characteristics of infantile depression. Affection, displayed in

the form of loving attention, tends to foster the trait of trust. Lack of affection

tends to foster the trait of mistrust. These last two statements concerning affection

tend to apply to future stages as well. In general, affection and positive reinforcement

tend to bring forth the positive traits.

Autonomy versus shame and doubt is associated with toddlerhood (two

to three years old). A toddler with a sense of autonomy will be interested in

exploring the immediate world and display an interest in novel stimulation. A

certain amount of self-direction will emerge. Conversely, a toddler with a sense

of shame and doubt will tend to hold back, to seem shy, and to lack selfconfidence.

(a) An infant with a sense of tends to thrive and expects good things to

happen.

(b) A lack of interest in the surrounding world and poor health are characteristics of

and to lack .

Answers: (a) trust; (b) infantile depression; (c) shame; self-confidence.

Initiative versus guilt is associated with the preschool period (three to six

years old). A preschooler with a sense of initiative will be likely to start a project

and see it through to completion. For example, four-year-old Rosalyn says, "I'm

going to color all of the pictures in my coloring book." Conversely, a preschooler

with a sense of guilt is hesitant, does not seek challenges, and holds back when an

opportunity for self-expression presents itself.

Industry versus inferiority is associated with middle childhood (six to

twelve years old). A child with a sense of industry will show an interest in school,

study, complete homework, agree to do reasonable chores, and in general display

responsible behavior. A child with a sense of inferiority will avoid studying,

homework, and chores. The child obtains no satisfaction from these activities,

particularly if the child often obtains poor grades or receives too much parental

criticism.

Developmental Psychology: How Children Become Adults 161

(a) A preschooler with a sense of will be likely to start a project and see it

through to completion.

(b) A child with a sense of will avoid studying, homework, and chores.

Answers: (a) initiative; (b) inferiority.

Identity versus role confusion is associated with adolescence (twelve to

eighteen years old). An adolescent with an identity has a sense of direction in life.

He or she already thinks in terms of a particular vocational area, has fairly welldefined

plans for the future, and a high level of self-esteem. Although goals are

not yet attained, they seem clearly desirable and possible. Conversely, an adolescent

suffering from role confusion imagines no particular pathway in life and

dreams of no well-shaped future. On the contrary, the future seems obscure and

formless.

Intimacy versus isolation is associated with young adulthood. This starts

when adolescence is over, usually around the age of eighteen. However, in practice,

young adulthood may be deferred for a number of years until an identity

has been attained. The present stage and the future stages to be discussed will

not be identified with particular years. A young adult with the capacity for intimacy

is able to form a close emotional bond with another person, often a marriage

partner. Intimacy exists when two people genuinely recognize the

importance of each other's thoughts and feelings. Informally, they can "be

themselves" with each other, and do not have to put on an act. Conversely, isolation

exists when an individual treats another individual like a thing, an object

to be manipulated and taken advantage of. The term I-thou relationship is

sometimes used to characterize intimacy; the term I-it relationship is used to

characterize isolation.

(a) An adolescent with an has a sense of direction in life.

(b) The term relationship is sometimes used to characterize intimacy.

Answers: (a) identity; (b) I-thou.

Generativity versus self-absorption is associated with adulthood. An adult

with the trait of generativity is capable of productive work. Usually he or she will

spend many years employed in a vocation or a well-defined social role (e.g., parent).

Generativity is linked to giving something of value to the world. The adult

with this trait contributes in some way to the welfare of others. Conversely, an

adult with the trait of self-absorption is concerned only with his or her own welfare.

Taking, not giving, is the theme of the person's life. He or she is, in essence,

a sort of parasite.

Integrity versus despair is associated with old age. An older person with the

162 PSYCHOLOGY

trait of integrity can face approaching death with a certain amount of acceptance.

There is relative peace of mind because the individual is convinced that his or her

life was spent well, that it had meaning. An older person in a state of despair has a

sense of desperation as life draws to its inevitable end. There is very little peace of

mind because the individual is thinking that he or she needs a second chance, an

opportunity to get life right.

Although the individual has very little control over the first few stages of life,

with adolescence and adulthood there is greater self-consciousness. There is a

growth in the ability to reflect and think. Consequently, the individual bears some

responsibility for the self-fashioning of the later stages.

(a) An adult with the trait of is capable of productive work.

(b) An adult with the trait of is concerned only with his or her own welfare.

amount of acceptance.

Answers: (a) generativity; (b) self-absorption; (c) integrity.

Piaget's Theory of Cognitive Development: From Magical

Thinking to Logical Thinking

The section on Erikson's theory concluded with a comment on the ability to

reflect and think. Jean Piaget (1896–1980), often recognized as the foremost child

psychologist of the twentieth century, made the growth of the child's ability to

think his particular domain of investigation.

Piaget, working primarily at Geneva University in Switzerland, began his

investigations into the workings of the child's mind because of an interest in

epistemology. Epistemology, a branch of philosophy, is the study of knowing.

Piaget wanted to discover how we come to know what we know. Or, more

accurately, he wanted to discover how we come to think we know what we

think we know.

The method that Piaget used to study the child's mind is called the phenomenological

method. The phenomenological method is characterized by asking

a child a series of carefully worded questions that direct the child's attention to

particular details of the child's immediate world. The child's responses reveal the

way in which the he or she thinks about the world. Piaget's investigations suggest

that there are four stages of cognitive development, the development of the

way in which the child thinks. Informally, cognitive development may be thought

of as the "growth of the mind."

Developmental Psychology: How Children Become Adults 163

(a) , a branch of philosophy, is the study of knowing.

(b) The method, used by Piaget, is characterized by asking a child a series of

carefully worded questions.

thinks.

Answers: (a) Epistemology; (b) phenomenological; (c) Cognitive.

According to Piaget, there are four stages of cognitive development: (1) the

sensorimotor stage, (2) the preoperational stage, (3) the concrete operations stage,

and (4) the formal operations stage.

The sensorimotor stage is associated with infancy (birth to two years old).

During this stage the infant has consciousness, but not self-consciousness. He or

she is, of course, aware of the environment. There are reflexes. A stimulus induces

a patterned, predictable motor response. This provides a clue to the term sensorimotor

and why Piaget chose it. The infant senses the world and, without reflection

or analysis, acts in response to his or her impressions.

In the older infant there is even a certain amount of intentional behavior. But

the infant does not know that he or she exists in the same way that an older child

or an adult knows that he or she exists. There is no way to establish these assertions

beyond doubt, because a verbal interview with an infant is impossible. However,

an infant acts as if self-consciousness is absent. For example, one-year-old

James is shown his reflection in a mirror. He is curious, of course, and reaches out

to touch the reflection. But he does not seem to know that he is seeing himself.

There appears to be no sense of recognition. A postage stamp is lightly stuck to

his forehead. He touches it in the mirror, but doesn't peel it off of his forehead.

Tested again, when he is a little over two years old, James immediately recognizes

that the stamp is on his own forehead, and, using the mirror, peels it off. He has

developed self-consciousness, a characteristic not of infancy, but of the next stage.

(a) During the sensorimotor stage the infant senses the world and, without or

, acts in response to his or her impressions.

(b) During the sensorimotor stage the infant has consciousness, but not .

Answers: (a) reflection; analysis; (b) self-consciousness.

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