Psychology, 4/e by Saul Kassin
CHAPTER 9:
Human Development
Human Development
Basic Developmental Questions
Prenatal Development
The Remarkable Newborn
The Infant and Growing Child
Adolescence
Adulthood and Old Age
Psychology, 4/e by Saul Kassin
©2004 Prentice Hall
Basic Developmental Questions
Developmental Psychology
The study of how people grow, mature,
and change over the life span

Two Major Ways to Conduct Research

Cross-sectional Studies
•People of different ages are tested and
compared

Longitudinal Studies
•The same people are tested at different times
to track changes related to age
Psychology, 4/e by Saul Kassin
©2004 Prentice Hall
Basic Developmental Questions
Developmental Research Strategies
Psychology, 4/e by Saul Kassin
©2004 Prentice Hall
Prenatal Development
The Growing Fetus
 Zygote

A fertilized egg that undergoes a two-week
period of rapid cell division and develops
into an embryo
 Embryo

The developing human organism, from two
weeks to two months after fertilization
 Fetus

The developing human organism, from nine
weeks after fertilization to birth
Psychology, 4/e by Saul Kassin
©2004 Prentice Hall
Prenatal Development
The Growing Fetus
Fertilization
30 Hours
6 weeks
4 months
Psychology, 4/e by Saul Kassin
©2004 Prentice Hall
Prenatal Development
The Growing Fetus
Teratogens
 Toxic substances that can harm the embryo or
fetus during prenatal development


Malnutrition
Viral Infections
• AIDS, Rubella (German measles), and others


X-rays, lead, and other environmental hazards
Drugs
• Alcohol (fetal alcohol syndrome), Cigarettes,
Cocaine, Aspirin, Marijuana, and other drugs both
licit and illicit
Psychology, 4/e by Saul Kassin
©2004 Prentice Hall
The Remarkable Newborn
Ways to Study the Abilities of Newborns
Habituation
The tendency for attention to a stimulus to
wane over time (often used to determine
whether an infant has “learned” a stimulus

Recovery
Following habituation to one stimulus, the
tendency for a second stimulus to arouse
new interest (often used to test whether
infants can discriminate between stimuli)

Psychology, 4/e by Saul Kassin
©2004 Prentice Hall
The Remarkable Newborn
Reflexes
 Grasping Reflex

In infants, an automatic tendency to grasp
an object that stimulates the palm
 Rooting Reflex

In response to contact on the cheek, an
infant’s tendency to turn toward the
stimulus and open its mouth
Psychology, 4/e by Saul Kassin
©2004 Prentice Hall
The Remarkable Newborn
Sensory Capacities
Visual Preferences in Newborns
 Infants spend more time
looking at patterns than
solids.
 Infants spend the most
time looking at a
drawing of a human
face.
 Is this just preference for
complexity or an
adaptation?
Psychology, 4/e by Saul Kassin
©2004 Prentice Hall
The Remarkable Newborn
Sensory Capacities
Newborn Orientation to the Face
 Infants were shown a blank
shape, a face, or scrambled
facial features.

The face and scrambled face
have same complexity.
 Infants looked more
intensely at the actual face.
Psychology, 4/e by Saul Kassin
©2004 Prentice Hall
The Remarkable Newborn
Sensory Capacities
Newborn Imitation
 Babies sometimes mimic
gestures made by others
who are within sight.


Sticking tongue out of
mouth
Moving head side to side
Psychology, 4/e by Saul Kassin
©2004 Prentice Hall
The Remarkable Newborn
Sensitivity to Number
Can Infants Add and Subtract?
 Infants saw a sequence
of events that illustrated
addition or subtraction.
 Then they saw a correct
or incorrect outcome
(2-1=2, for example).
 The infant looked
longer at outcomes that
were incorrect.
Psychology, 4/e by Saul Kassin
©2004 Prentice Hall
The Infant and Growing Child
Biological Development
The Developing Brain
Psychology, 4/e by Saul Kassin
©2004 Prentice Hall
The Infant and Growing Child
Cognitive Development
Piaget’s Theory
 Schemas


In Piaget’s theory, mental representations of
the world that guide the processes of
assimilation and accommodation
Assimilation
• The process of incorporating and, if necessary,
changing new information to fit existing schemas

Accommodation
• The process of modifying existing schemas in
response to new information
Psychology, 4/e by Saul Kassin
©2004 Prentice Hall
The Infant and Growing Child
Cognitive Development
Changing Schemas of the Earth
 From preschool
through about the 5th
grade, children
gradually assimilate
and then accommodate
their schemas to form
an accurate
representation of the
earth’s shape.
Psychology, 4/e by Saul Kassin
©2004 Prentice Hall
5th grade
Preschool
The Infant and Growing Child
Cognitive Development
Piaget’s Stages of Development
 Stages of Development






Each stage is qualitatively different from others
Ages for stage transitions are approximate
Sensorimotor
Preoperational
Concrete Operational
Formal Operational
Psychology, 4/e by Saul Kassin
©2004 Prentice Hall
The Infant and Growing Child
Cognitive Development
Piaget’s Stages of Cognitive Development
Psychology, 4/e by Saul Kassin
©2004 Prentice Hall
The Infant and Growing Child
Cognitive Development
 Separation anxiety is a
fear reaction in response
to the absence of the
primary caregiver.
 It is seen in all cultures.
 It corresponds with the
development of object
permanence and the
sensorimotor stage of
cognitive development.
Separation Anxiety
Psychology, 4/e by Saul Kassin
©2004 Prentice Hall
The Infant and Growing Child
Cognitive Development
Tasks Used to Test Conservation
 The ability to conserve
marks the transition
from the preoperational
stage to the concrete
operational stage of
cognitive development.
Psychology, 4/e by Saul Kassin
©2004 Prentice Hall
The Infant and Growing Child
Cognitive Development
Speed of Information Processing
 Response times decrease from 7 - 12 years of age
 Consistent across several different types of tasks
 This may be due to the biological maturation of the brain
 Increased myelination of axons which speeds up neural
processing
Psychology, 4/e by Saul Kassin
©2004 Prentice Hall
The Infant and Growing Child
Social Development
The Parent-Child Relationship
 Critical Period

A period of time during which an organism
must be exposed to a certain stimulus for
proper development to occur
 Attachment

A deep emotional bond that an infant
develops with its primary caretaker
Psychology, 4/e by Saul Kassin
©2004 Prentice Hall
The Infant and Growing Child
Social Development
Styles of Attachment
 Strange Situation Test

A parent-infant “separation and reunion” procedure
that is staged in a laboratory to test the security of a
child’s attachment
 Secure Attachment

The baby is secure when the parent is present,
distressed by separation, and delighted by reunion.
 Insecure Attachment

The baby clings to the parent, cries at separation,
and reacts with anger or apathy to reunion.
Psychology, 4/e by Saul Kassin
©2004 Prentice Hall
Adolescence
Adolescence
The period of life from puberty to
adulthood, corresponding roughly to the ages
of 13 to 20

Puberty
The onset of adolescence, as evidence by
rapid growth, rising levels of sex hormones,
and sexual maturity

Menarche

A girl’s first menstrual period
Psychology, 4/e by Saul Kassin
©2004 Prentice Hall
Adolescence
Puberty
Adolescent Growth Spurt
 At about age 13 for girls, 16 for boys, there is a
final maturational growth spurt in height.
Psychology, 4/e by Saul Kassin
©2004 Prentice Hall
Adolescence
Puberty
The Timing of Puberty and Body Images in Girls
 Girls who mature
earlier than their
peers are usually
less satisfied with
their size, weight,
and figure.
Psychology, 4/e by Saul Kassin
©2004 Prentice Hall
Adolescence
Puberty
The Timing of Puberty and Body Images in Boys
 Boys who mature
later than their
peers have negative
body images, but
they are only
temporary.
Psychology, 4/e by Saul Kassin
©2004 Prentice Hall
Adolescence
Cognitive Development
Kohlberg’s Stages of Moral Reasoning
 Moral Reasoning

The way people think and try to solve moral
dilemmas.
 Preconventional Level

Morality judged in terms of reward and punishment
 Conventional Level

Morality judged in terms of social order and approval
 Postconventional Level

Morality judged in terms of abstract principles, like
equality and justice
Psychology, 4/e by Saul Kassin
©2004 Prentice Hall
Adolescence
Cognitive Development
Kohlberg’s Levels of Moral Reasoning
 Most 7-10 year olds are
reasoning at the
preconventional level.
 Most 13-16 year olds are
reasoning at the
conventional level.
 Few participants show
reasoning indicative of
the postconventional
level.
Psychology, 4/e by Saul Kassin
©2004 Prentice Hall
Adolescence
Cognitive Development
Criticisms of Kohlberg’s Theory
 Cultural Bias

Some cultural differences are not reflected in
this theory.
 Gender Bias

Empirical support for this claim is weak.
 Connection between moral reasoning and
moral behavior is often indirect.
Psychology, 4/e by Saul Kassin
©2004 Prentice Hall
Adolescence
Social and Personal Development
Adolescent Disengagement
 The proportion of time spent
with the family decreases
almost 3% per year
 This decline was not found for
time spent alone with parents
 Identity Crisis

An adolescent’s struggle to
establish a personal
identity, or self-concept
Psychology, 4/e by Saul Kassin
©2004 Prentice Hall
Adolescence
Social and Personal Development
Patterns of Adolescent
“Transformation”Within the Family
 Adolescents in the 7th and
8th grades felt worse
while with their family.
 Boys feel better after 8th
grade and feel the best in
9th and 10th grades.
 Girls continue to feel bad
until the 10th grade.
Psychology, 4/e by Saul Kassin
©2004 Prentice Hall
Adolescence
Social and Personal Development
 Peer Influences



Adolescent relationships are intimate.
Adolescents begin to discover friendships with
other-sex peers.
Conformity rises steadily with age, peaks in
ninth grade, and then declines.
Psychology, 4/e by Saul Kassin
©2004 Prentice Hall
Adolescence
Social and Personal Development
 Sexuality



Whether teens act on sexual impulses depends
on social factors.
Adolescents who engage in sexual behavior
with others are not necessarily informed about
health risks and contraception .
Adolescent sexual behavior may be due to
attempts to be more like an adult or as way to
rebel.
Psychology, 4/e by Saul Kassin
©2004 Prentice Hall
Adolescence
Adolescence and Mental Health
 The stereotypic images of adolescents are:

Mood swings, identity crises, anxiety, rebelliousness,
depression, drug use, and suicide
 Three perceived sources of difficulty in
adolescence are:

Conflict with parents, risk-taking behavior, and mood
disruption
 Conflict with parents and risk-taking do occur, but
the idea that adolescents are in a state of distress is
exaggerated.
Psychology, 4/e by Saul Kassin
©2004 Prentice Hall
Adulthood and Old Age
Physical Changes in Adulthood
 Life Span

The maximum age possible for members of a
given species.
 Life Expectancy

The number of years that an average
member of a species is expected to live.
 Menopause

The end of menstruation and fertility.
Psychology, 4/e by Saul Kassin
©2004 Prentice Hall
Adulthood and Old Age
Aging and Intellectual Functions
 Memory and Forgetting



Cognitive abilities do not inevitably decline.
Some elderly may show declines on free-recall
tasks, however declines on tests of recognition
memory are less likely.
Memory declines may be due to impairments in
sensory acuity and a slowing of neuronal
processing.
Psychology, 4/e by Saul Kassin
©2004 Prentice Hall
Adulthood and Old Age
Aging and Intellectual Functions
The Alzheimer’s Problem
 Alzheimer’s Disease

A progressive brain
disorder that strikes
older people, causing
memory loss and other
symptoms.
 In the U.S., the projected
number of Alzheimer’s
patients is 14 million in
2050.
 The cost is at least $100
billion per year.
Psychology, 4/e by Saul Kassin
©2004 Prentice Hall
Adulthood and Old Age
Aging and Intellectual Functions
Age Trends in Measures of Intelligence
 Fluid intelligence, which
includes inductive reasoning
and spatial ability, declines
steadily throughout middle
and late adulthood.
 Crystallized intelligence,
which includes verbal
ability and numeric ability,
remains stable into the 70’s.
Psychology, 4/e by Saul Kassin
©2004 Prentice Hall
Adulthood and Old Age
Aging and Intellectual Functions
Timed vs. Untimed Vocabulary Tests
 Some abilities are less affected by age than are others.
 Scores declined only in the timed test.
Psychology, 4/e by Saul Kassin
©2004 Prentice Hall
Adulthood and Old Age
Social and Personal Development
Erikson’s Eight Stages of Development - I
 Trust vs. Mistrust

Infancy (0-1 year)
 Autonomy vs. Shame and Doubt

Toddler (1-2 years)
 Initiative vs. Guilt

Preschool (3-5 years)
 Industry vs. Inferiority

Elementary School (6-12 years)
Psychology, 4/e by Saul Kassin
©2004 Prentice Hall
Adulthood and Old Age
Social and Personal Development
Erikson’s Eight Stages of Development - II
 Identity vs. Role confusion

Adolescence (13-19 years)
 Intimacy vs. Isolation

Young adulthood (20-40 years)
 Generativity vs. Stagnation

Middle adulthood (40-65 years)
 Integrity vs. Despair

Late adulthood (65 and older)
Psychology, 4/e by Saul Kassin
©2004 Prentice Hall
Adulthood and Old Age
Social and Personal Development
Life Satisfaction
 In multiple
cultures, 75-80%
say they are
satisfied with life.
 Ratings of life
satisfaction do not
vary with age.
Psychology, 4/e by Saul Kassin
©2004 Prentice Hall
Adulthood and Old Age
Social and Personal Development
Self-Esteem
 Self-esteem is highest
in childhood.
 It drops sharply during
adolescence.
 It increases gradually
during adulthood,
peaks in the sixties,
and declines in old
age.
Psychology, 4/e by Saul Kassin
©2004 Prentice Hall
Adulthood and Old Age
Dying and Death
 Elisabeth Kübler-Ross proposed five stages in
approaching death:





Denial (“It must be a mistake.”)
Anger (“It isn’t fair!”)
Bargaining (“Let me live longer and I’ll be a better person.”)
Depression (“ I’ve lost everything important to me.”)
Acceptance (“What has to be, has to be.”)
 Not everyone follows this sequence through the stages
and all people do not experience all stages.
Psychology, 4/e by Saul Kassin
©2004 Prentice Hall