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DEV EVEL LOPM MEN
DEV
EVEL
LOPM
MEN
NTAL
AL
PS
SYCH
HOL
LOG
GY (P
PAPE
ER I))
CORE COURSE For
B
B. Sc Couns
C
sellinng Psyycholoogy
III SEMES
STER
(20111 Adm
mission)
UNIVERSSITY O
OF CALICUTT SCH
HOOL OF DISTANC
CE EDUCA
ATION CALICUT UNIVER
RSITY PO, M
MALAPPUR
RAM, KERA
ALA, INDIA
A ‐ 673 63
35
School of Distance Education UNIVERSITY OF CALICUT SCHOOL OF DISTANCE EDUCATION STUDY MATERIAL Core Course for B Sc Counselling Psychology III Semester DEVELOPMENTAL PSYCHOLOGY (PAPER I)
Prepared by Scrutinised by: Layout: Smt. Sujisha. T.G, Assistant Professor, Department of Psychology, Govt. College, Chittur.
Prof. C. Jayan,
Department of Psychology,
University of Calicut. Computer Section, SDE ©
Reserved
Developmental Psychology (Paper I) Page 2 School of Distance Education CONTENTS
Page
MODULE 1
5
MODULE 2
19
MODULE 3
31
Developmental Psychology (Paper I) Page 3 School of Distance Education Developmental Psychology (Paper I) Page 4 School of Distance Education MODULE 1
Introduction to Life Span Development and Theories
Development describes the growth of humans throughout the lifespan, from
conception to death. The scientific study of human development seeks to understand
and explain how and why people change throughout life. This includes all aspects of
human growth, including physical, emotional, intellectual, social, perceptual, and
personality development. Developmental psychology, also known as Human
Development, is the scientific study of progressive psychological changes that occur
in human beings as they age. Originally concerned with infants and children, and
later other periods of great change such as adolescence and aging, it now
encompasses the entire life span. This field examines change across a broad range of
topics including motor skills and other psycho-physiological processes, problem
solving abilities, conceptual understanding, acquisition of language, moral
understanding, and identity formation.
IMPORTANCE OF LIFE SPAN DEVELOPMENT
Studying life-span development will help you to better understand normal
and abnormal behavior and development in humans. Life-span development is
fascinating and intriguing, especially when one considers the millions of possibilities
there are in the direction that this growth and development can take a person.
Understanding life-span development will help better to understand the stages
humans go through, and how variances in circumstances can affect the outcomes of
these stages of development. Understanding life-span development, as well as the
parent’s integral role in the child’s stages of life, may help you to better raise your
child in a positive and nurturing manner. Regardless of the reason for studying lifespan development, everyone has something to gain from the subject. Whether you
are young or old, plan to have children or not, life-span development is something
that each and every one of us is continually going through and better understanding
it may enable us to better understand ourselves, and those around us.
Historical Foundations
Contemporary theories of human development are the result of centuries of
change in Western cultural values, philosophical thinking, and scientific progress. To
understand the field as it exists today, we must return to its beginnings—to
influences that long preceded scientific study.
Philosophies of Childhood
Developmental Psychology (Paper I) Page 5 School of Distance Education As early as medieval Europe (the sixth through the fifteenth centuries),
childhood was regarded as a separate period from adulthood. Medieval painters
often depicted children in loose, comfortable gowns while playing games and
looking up to adults. Laws recognized that children needed protection from people
who might mistreat them, and courts exercised leniency with lawbreaking youths
because of their tender years. Medieval religious writings, however, contained
contradictory beliefs about children’s basic nature, sometimes portraying them as
possessed by the devil and in need of purification, at other times as innocent and
close to angels (Hanawalt, 2003).
John Locke. The philosophies of the seventeenth-century enlightenment emphasized
ideals of human dignity and respect. The writings of British philosopher John Locke
(1632–1704) served as the forerunner of a twentieth-century perspective that we will
discuss shortly: behaviorism. Locke viewed the child as a tabula rasa—Latin for
“blank slate.” According to this idea, children are, to begin with, nothing at all; their
characters are shaped by experience. Locke (1690/1892) described parents as rational
tutors who can mold the child in any way they wish through careful instruction,
effective example, and rewards for good behavior.
Jean-Jacques Rousseau. In the eighteenth century, French philosopher Jean-Jacques
Rousseau (1712–1778) claimed that children are not blank slates to be filled by adult
instruction. Instead, Rousseau (1762/1955) viewed children as noble savages,
naturally endowed with a sense of right and wrong and with an innate plan for
orderly, healthy growth. Unlike Locke, Rousseau thought children’s built-in moral
sense and unique ways of thinking and feeling would only be harmed by adult
training.
Rousseau’s philosophy includes two influential concepts: (1)Stage, which we
discussed earlier in this chapter, and (2) maturation, which refers to a genetically
determined, naturally unfolding course of growth. Unlike Locke, Rousseau saw
children as determining their own destinies. And he saw development as a
discontinuous, stage wise process that follows a single, unified course mapped out
by nature.
Darwin: Forefather of Scientific Child Study. British naturalist Charles Darwin
(1809–1882) observed the infinite variation among plant and animal species. He also
saw that within a species, no two individuals are exactly alike. From these
observations, he constructed his famous theory of evolution. The theory emphasized
two related principles: natural selection and survival of the fittest. Darwin explained
that certain species survive in particular environments because they have
Developmental Psychology (Paper I) Page 6 School of Distance Education characteristics that fit with, or are adapted to, their surroundings. Other species die
off because they are not well suited to their environments. Individuals within a
species who best meet the survival requirements of the environment live long
enough to reproduce and pass their more beneficial characteristics to future
generations.
The Normative Period. G. Stanley Hall (1846–1924), one of the most influential
American psychologists of the early twentieth century, is generally regarded as the
founder of the child study movement (Hogan, 2003). He also foreshadowed lifespan
research by writing one of the few books of his time on aging. Inspired by Darwin’s
work, Hall and his well-known student Arnold Gesell (1880–1961) devised theories
based on evolutionary ideas. They regarded development as a genetically
determined process that unfolds automatically, much like a flower (Gesell, 1933;
Hall, 1904).
Characteristics of the Life-Span Perspective
The belief that development occurs throughout life is central to the life-span
perspective on human development, but this perspective has other characteristics as
well. According to life-span development expert Paul Baltes (1939–2006), the lifespan
perspective views development as lifelong, multidimensional, multidirectional,
plastic, multidisciplinary, and contextual, and as a process that involves growth,
maintenance, and regulation of loss . Let’s look at each of these characteristics.
Development Is Lifelong In the life-span perspective, early adulthood is not the
endpoint of development; rather, no age period dominates development. Researchers
increasingly study the experiences and psychological orientations of adults at
different points in their lives. Later in this chapter, we consider the age periods of
development and their characteristics.
Development Is Multidimensional At every age, your body, your mind, your
emotions, and your relationships change and affect each other. Development consists
of biological, cognitive, and socioemotional dimensions. Even within one of these
dimensions, there are many components—for example, attention, memory, abstract
thinking, speed of processing information, and social intelligence are just a few of the
components of the cognitive dimension.
Development Is Multidirectional Throughout life, some dimensions or components
of a dimension expand and others shrink. For example, when one language(such as
English) is acquired early in development, the capacity for acquiring second and
third languages (such as Spanish and Chinese) decreases later in development,
Developmental Psychology (Paper I) Page 7 School of Distance Education especially after early childhood (Levelt, 1989). During adolescence, as individuals
establish romantic relationships, their time spent with friends may decrease.
Development Is Plastic Plasticity means the capacity for change. For example, can
you still improve your intellectual skills when you are in your seventies or eighties?
Researchers have found that the cognitive skills of older adults can be improved
through training and developing better strategies (Boron, Willis, & Schaie, 2007).
However, possibly we possess less capacity for change when we become old (Baltes,
Reuter-Lorenz, & Rösler, 2006).
Developmental Science Is Multidisciplinary Psychologists, sociologists,
anthropologists, neuroscientists, and medical researchers all share an interest in
unlocking the mysteries of development through the life span. How do your heredity
and health limit your intelligence? Do intelligence and social relationships change
with age in the same way around the world? How do families and schools influence
intellectual development? These are examples of research questions that cut across
disciplines.
Development Is Contextual All development occurs within a context, or setting.
Contexts include families, neighborhoods, schools, peer groups, churches, university
laboratories, cities, countries, and so on. Each of these settings is influenced by
historical, economic, social, and cultural factors (Shiraev & Levy, 2010).Contexts, like
individuals, change. Thus, individuals are changing beings in a changing world.
Development Involves Growth, Maintenance, and Regulation of Loss
Baltes and his colleagues (2006) assert that the mastery of life often involves
conflicts and competition among three goals of human development: growth,
maintenance, and regulation of loss. As individuals age into middle and late
adulthood, the maintenance and regulation of loss in their capacities take center
stage away from growth. Thus, a 75-year-old man might aim not to improve his
memory or his golf swing but to maintain his independence and merely to play golf.
NATURE OF DEVELOPMENT
Biological, Cognitive, and Socio-emotional Processes
The nature of development is complex because it is the product of biological,
cognitive, and socio-emotional processes.
Developmental Psychology (Paper I) Page 8 School of Distancce Education
n Biollogical Processes:
P
Biologicaal processees producee changess in an in
ndividual’ss
physical naturre. Genes inherited
i
f
from
paren
nts, the dev
velopmentt of the bra
ain, heightt
and weight gaains, chang
ges in motor skills, n
nutrition, exercise,
e
th
he hormonal changess
of puberty,
p
an
nd cardiov
vascular deecline are all
a examplles of biolo
ogical proccesses thatt
affecct development.
Cog
gnitive prrocesses Cognitive processess refer to changes in the in
ndividual’ss
thou
ught, intellligence, an
nd languag
ge. Watchin
ng a colorfful mobilee swinging above thee
crib,, putting together a two-word
d sentence, memoriziing a poem
m, imaginin
ng what itt
wou
uld be likee to be a movie sttar, and solving a crossword
d puzzle all
a involvee
cogn
nitive proccesses.
Socio-emotio
onal Proccesses Soccio-emotioonal proceesses invoolve chang
ges in thee
individual’s reelationship
ps with otther peoplee, changess in emotio
ons, and changes
c
in
n
perssonality. An
A infant’s smile in reesponse to
o a parent’s touch, a toddler’s aggressivee
attacck on a playmate,, a schoo
ol-age chilld’s devellopment o
of assertiv
veness, an
n
adollescent’s jo
oy at the senior prom
m, and thee affection of an eldeerly couplee all reflectt
the role of socio-emot
s
tional pro
ocesses in
n developm
ment. Con
nnecting Biological,,
Cog
and socio--emotionall
gnitive, and
d Socio-em
motional Prrocesses Biological, cognitive,
c
proccesses aree inextricaably interrtwined (D
Diamond, 2009; D
Diamond, Casey, &
Mun
nakata, 20110).
PER
RIODS O
OF LIFES
SPAN
Infan
ncy
Birth-two years.
B
y
Whille the infan
nt is depen
ndent on ad
dults for most
m
things,,
m
many
psych
hological ch
haracteristiccs are rapid
dly developing. During
g this stage,,
t
the
bond th
hat develop
ps between
n the infantt and theirr primary caregiver
c
iss
i
important
in
n terms of the
t infant’s later emotional develo
opment.
Childhood
Two-ten yeears. During
T
g this stage, children become
b
incrreasingly in
ndependentt
f
from
their parents
p
as they
t
learn to
t do thing
gs themselvees and gain
n more self-c
control.
Du
uring this sttage, childrren’s cognittive skills d
develop and they also
o
b
begin
to dev
velop an un
nderstandin
ng of what is right and wrong.
Ado
olescence
Ten-twenty
T
y years. Thee onset of puberty
p
marrks the beg
ginning of adolescence
a
.
I is domina
It
ated by seeeking indep
pendence fro
om parents and develo
oping one’ss
o
own
identitty. Comparred to the cchild, an ad
dolescent’s thought prrocesses aree
m
more
logicaal, complex and idealistic.
Devellopmental Psyychology (Pap
per I) Page 9
9 School of Distancce Education
n Early
y
Adu
ulthood
Twenty-fortty years. This
T
T
is the sstage of esttablishing p
personal an
nd financiall
i
independen
nce and estaablishing an
nd consolidating a careeer. For man
ny, it is also
o
t time in which individuals sellect a partn
the
ner, develop
p an ongoin
ng intimatee
r
relationship
p and begin
n a family.
Middle Age
Forty-sixty five yearss. This is a period off expanding
F
g social an
nd personall
i
involvemen
nts and reesponsibilitiies, advanccing a carreer, and supporting
g
o
offspring
in
n their devellopment to becoming mature
m
indiividuals.
Oldeer Age
Sixty five yeears plus. A period of considerab
S
ble adjustmeent to chang
ges in one’ss
l and selff-perception
life
ns. For man
ny older peo
ople, this iss a very libeerating timee
w
when
they no longer have
h
the daay-to-day reesponsibility
y of looking
g after theirr
c
children
or working.
Devellopmentaal Researrch
The purrpose of developmen
ntal researrch is to assess chang
ges over an
n extended
d
period of timee. For exa
ample, dev
velopmenttal research
h would b
be an ideall choice to
o
asseess the diffferences in
n academiic and soccial develo
opment in
n low-incom
me versuss
high
h-income n
neighborho
oods. It is
i most co
ommon wh
hen workiing with children
c
ass
subjects for obvious
o
r
reasons
an
nd can be underta
aken using
g several methods:
long
gitudinal, cross
c
sectio
onal, and cross sequeential.
Lon
ngitudinall Studiess.
Longitu
udinal stu
udies assesss changess over an
n extended
d
period of timee by lookin
ng at the same
s
groups of subjeects for months or even
e
years.
Look
king at aca
ademic an
nd social developmen
d
nt, we ma
ay choose a small sam
mple from
m
each
h of the low
w- and hig
gh-income areas and
d assess theem on various measu
ures every
y
six months
m
forr a period of ten years. The results of lon
ngitudinall studies ca
an providee
valu
uable qualiitative and
d quantitattive data reegarding the
t differen
nces in dev
velopmentt
betw
ween vario
ous groups.
The maajor concerrn with lon
ngitudinal research, aside
a
from
m the obvio
ous lack off
ardization,, is the leng
gth of timee it takes to
o completee
conttrol, randomization, and standa
the study.
s
Ima
agine startting a projeect that mu
ust be consstantly maintained fo
or a period
d
of teen or moree years. Th
he subject mortality rate due to
t illness, rrelocation, and otherr
facto
ors alone could
c
resu
ult in majo
or concernss, not to mention
m
th
he amount of energy
y
and time that must
m
be deevoted to the
t research
h.
Devellopmental Psyychology (Pap
per I) Page 10
0 School of Distance Education Cross Sectional Studies. One way to reduce the amount of time and the mortality
rate in a developmental study is to assess different ages at the same time rather than
using the same groups over an extended period. A cross sectional study might look
at the same theory regarding academic and social development but assess a small
group of three year olds, six year olds, nine year olds and 12 year olds at the same
time.
The assumption is that the differences between the age ranges represent
natural development and that of a longitudinal study had been used, similar results
would be found. The obvious benefit is in the length of time it takes to complete the
study, but the assumptions that the six year old group will achieve the same
academic and social development as the nine year old group can be invalid.
Cross Sequential Studies. Cross sequential studies combine both longitudinal and
cross sectional methods in an attempt to both shorten the length of the research and
minimize developmental assumptions. For this method, groups of different age
children (three, six, and nine for example) may be studied for a period of three years
to both assess developmental changes and assure that the typical three year old is
similar to the typical 6 year old after three years of development.
THEORIES OF DEVELOPMENT
We will briefly outline major theoretical perspectives on development:
Psychoanalytic cognitive, behavioral and social cognitive.
Psychoanalytic Theories
Freud’s theory has three main parts, the stages of development, the structure of the
personality, and his description of mental life. Here, the stages of the personality will
be discussed. The first stage is the Oral Stage. It runs from birth to age 2. In the oral
stage infants and toddler explored the world primarily with their most sensitive area,
their mouths. They also learn to use their mouths to communicate. The next stage is
the Anal Stage. In the anal stage, children learned to control the elimination of bodily
wastes.
The Phallic Stage (3-5 years of age) is probably the most controversial. The word
phallic means penis-like. In this stage, children discover their sexual differences. The
controversy comes from Freud’s description of the Oedipus (for males) and Electra
(for females) complexes, with their attendant concepts of castration anxiety and penis
envy, respectively. Those complexes lead, according to Freudian theory, to normal
Developmental Psychology (Paper I) Page 11 School of Distance Education differentiation of male and female personalities. The defense mechanism of
repression was invoked to explain why no one could remember the events of this
stage.
The phallic stage is followed by a Latency Period in which little new development
is observable. In this stage, boys play with boys, and girls with girls, typically. Sexual
interest is low or non-existent. The final stage is the Genital Stage. It started around
12 years of age and ends with the climax of puberty. Sexual interests re-awaken at
this time (there were sexual interests before, dormant and repressed from the phallic
stage).
Ericksons theory of psychosocial development
Erik Erickson described development that occurs throughout the lifespan.
Learn more in this chart summarizing Erikson’s stages of psychosocial development.
Stage
Basic Conflict
Infancy (birth Trust
to 18 months) Mistrust
Important
Events
Outcome
vs. Feeding
Children develop a sense of trust when
caregivers provide reliability, care, and
affection. A lack of this will lead to
mistrust.
Early
Autonomy vs. Toilet
Childhood (2 Shame
and Training
to 3 years)
Doubt
Children need to develop a sense of
personal control over physical skills and a
sense of independence. Success leads to
feelings of autonomy, failure results in
feelings of shame and doubt.
Preschool (3 to Initiative
5 years)
Guilt
Children need to begin asserting control
and power over the environment. Success
in this stage leads to a sense of purpose.
Children who try to exert too much power
experience disapproval, resulting in a
sense of guilt.
vs. Exploration
Developmental Psychology (Paper I) Page 12 School of Distance Education School Age (6 Industry vs. School
to 11 years)
Inferiority
Children need to cope with new social
and academic demands. Success leads to a
sense of competence, while failure results
in feelings of inferiority.
Adolescence
Identity
vs. Social
(12
to
18 Role
Relationships
years)
Confusion
Teens need to develop a sense of self and
personal identity. Success leads to an
ability to stay true to yourself, while
failure leads to role confusion and a weak
sense of self.
Yound
Intimacy
Adulthood (19 Isolation
to 40 years)
Young adults need to form intimate,
loving relationships with other people.
Success leads to strong relationships,
while failure results in loneliness and
isolation.
vs. Relationships
Middle
Generativity
Work
and Adults need to create or nurture things
Adulthood (40 vs. Stagnation Parenthood
that will outlast them, often by having
to 65 years)
children or creating a positive change that
benefits other people. Success leads to
feelings
of
usefulness
and
accomplishment, while failure results in
shallow involvement in the world.
Maturity(65 to Ego Integrity Reflection on Older adults need to look back on life and
death)
vs. Despair
Life
feel a sense of fulfillment. Success at this
stage leads to feelings of wisdom, while
failure results in regret, bitterness, and
despair.
Cognitive Theories
Whereas psychoanalytic theories mainly focus on socio-emotional processes,
cognitive theories emphasize thinking, reasoning, language and other cognitive
processes.
Developmental Psychology (Paper I) Page 13 School of Distance Education PIAGET’s theory of cognitive development
Swiss biologist and psychologist Jean Piaget (1896-1980) observed his children (and
their process of making sense of the world around them) and eventually developed a
four-stage model of how the mind processes new information encountered. He
posited that children progress through 4 stages and that they all do so in the same
order. These four stages are:
Sensorimotor stage (Birth to 2 years old). The infant builds an understanding of
himself or herself and reality (and how things work) through interactions with the
environment. It is able to differentiate between itself and other objects. Learning
takes place via assimilation (the organization of information and absorbing it into
existing schema) and accommodation (when an object cannot be assimilated and the
schemata have to be modified to include the object.
Preoperational stage (ages 2 to 4). The child is not yet able to conceptualize
abstractly and needs concrete physical situations. Objects are classified in simple
ways, especially by important features.
Concrete operations (ages 7 to 11). As physical experience accumulates,
accomodation is increased. The child begins to think abstractly and conceptualize,
creating logical structures that explain his or her physical experiences.
Formal operations (beginning at ages 11 to 15). Cognition reaches its final form. By
this stage, the person no longer requires concrete objects to make rational
judgements. He or she is capable of deductive and hypothetical reasoning. His or her
ability for abstract thinking is very similar to an adult.
Vygotsky’s sociocultural cognitive theory
Lev Vygotsky offers an alternative to Piaget’s views on development. His
sociocultural theory of development states that Children learn through social
interactions and their culture. Vygotsky believed that through dialogues we interact
socially and communicate the values of our cultures to others. Vygotsky is best
known for being an educational psychologist with a sociocultural theory. This theory
suggests that social interaction leads to continuous step-by-step changes in children’s
thought and behavior that can vary greatly from culture to culture (Woolfolk, 1998).
Basically Vygotsky’s theory suggests that development depends on interaction with
people and the tools that the culture provides to help form their own view of the
world. There are three ways a cultural tool can be passed from one individual to
another. The first one is imitative learning, where one person tries to imitate or copy
Developmental Psychology (Paper I) Page 14 School of Distance Education another. The second way is by instructed learning which involves remembering the
instructions of the teacher and then using these instructions to self-regulate. The final
way that cultural tools are passed to others is through collaborative learning, which
involves a group of peers who strive to understand each other and work together to
learn a specific skill (Tomasello, et al., 1993). Children will acquire the ways of
thinking and behaving that make up a culture by interacting with a more
knowledgeable person. Vygotsky believed that social interaction will lead to ongoing
changes in a child’s thought and behavior. Theses thoughts and behaviors would
vary between cultures (Berk, 1994).
The second element in the sociocultural theory is the zone of proximal
development (ZPD). Vygotsky believed that any pedagogy creates learning processes
that lead to development and this sequence results in zones of proximal
development. It’s the concept that a child accomplishes a task that he/she cannot do
alone, with the help from a more skilled person. Vygotsky also described the ZPD as
the difference between the actual development level as determined by individual
problem solving and the level of potential development as determined through
problem solving under adult guidance or collaboration with more knowledgeable
peers. The result of this process is children become more socialized in the dominant
culture and it induces cognitive development (Moll, 1994).
The Information-Processing Approach.
According to the information-processing approach, individuals develop a
gradually increasing capacity for processing information, which allows them to
acquire increasingly complex knowledge and skills (Bjorklund & Rosenbaum, 2000;
Chen & Siegler, 2000; Siegler, 2001). Unlike Piaget’s cognitive developmental theory,
the information processing approach does not describe development as being
stagelike.
Although a number of factors stimulated the growth of the informationprocessing approach, none was more important than the computer, which
demonstrated that a machine could perform logical operations. Psychologists drew
analogies to computers to explain the relation between cognition or thinking and the
brain. The physical brain is said to be analogous to the computer’s hardware,
cognition to its software. Although computers and software are not perfect analogies
for brains and cognitive activities, the comparison contributed to our thinking about
the mind as an active information-processing system.
Developmental Psychology (Paper I) Page 15 School of Distance Education Robert Siegler (1998), a leading expert on children’s information processing,
believes that thinking is information processing. He says that when individuals
perceive, encode, represent, store, and retrieve information, they are thinking. Siegler
believes that an important aspect of development is learning good strategies for
processing information.
Behavioural and Social Cognitive Theories
Behaviourists believe essentially that we can study scientifically only what can
be directly observed and measured. At about the same time as Freud was
interpreting patients’ unconscious minds through their early childhood experiences,
Ivan Pavlov and John B.Watson were conducting detailed observations of behaviour
in controlled laboratory settings. Out of the behavioural tradition grew the belief that
development is observable behaviour that can be learned through experience with
the environment.
Pavlov’s Classical Conditioning In the early 1900s, Russian physiologist Ivan
Pavlov (1927) knew that dogs innately salivate when they taste food. He became
curious when he observed that dogs salivate to various sights and sounds before
eating their food. For example, when an individual paired the ringing of a bell with
the food, the bell ringing subsequently developed the ability to elicit the salivation of
the dogs when it was presented by itself. Pavlov discovered the principle of classical
conditioning, in which a neutral stimulus (in our example, ringing a bell) acquires
the ability to produce a response originally produced by another stimulus (in our
example, food).
In the 1920s, John Watson wanted to show that Pavlov’s concept of classical
conditioning could be applied to human beings. A little boy named Albert was
shown a white rat to see if he was afraid of it. He was not. As Albert played with the
rat, a loud nose was sounded behind his head. As you might imagine, the noise
caused little Albert to cry. After only several pairings of the loud noise and the white
rat, Albert began to fear the rat even when the noise was not sounded (Watson &
Raynor, 1920). Similarly, many of our fears—fear of the dentist from a painful
experience, fear of driving from being in an automobile accident, fear of heights from
falling off a high chair when we were infants, or fear of dogs from being bitten—can
be learned through classical conditioning.
Although Watson’s study (Watson & Raynor, 1920) provided the scientific
community with valuable information, the kind of experimental manipulation
Developmental Psychology (Paper I) Page 16 School of Distance Education performed on Little Albert would be considered unethical by today’s standards.
Later in the chapter we will discuss the ethical precautions that must be taken in
studying individuals.
Skinner’s Operant Conditioning In B. F. Skinner’s (1938) operant conditioning,
the consequences of a behaviour produce changes in the probability of the
behaviour’s future occurrence. If a behaviour is followed by a rewarding stimulus, it
is more likely to recur, but if a behaviour is followed by a punishing stimulus, it is
less likely to recur. For example, when a person smiles at a child after the child has
done something, the child is more likely to engage in the activity than if the person
gives the child a nasty look. For Skinner, such rewards and punishments shape
individuals’ development.
Social Cognitive Theory Some psychologists believe that the behaviourists
basically are right when they say development is learned and is influenced strongly by
environmental experiences. However, Skinner went too far in declaring that cognition is
unimportant to understanding development. Social cognitive theory is the view of
psychologists who emphasize behaviour, environment, and cognition as the key factors in
development.
American psychologists Albert Bandura (1986, 1998, 2000) and Walter Mischel
(1973, 1995) are the main architects of social cognitive theory’s contemporary version,
which Mischel (1973) initially labelled cognitive social learning theory. Both Bandura
and Mischel believe that cognitive processes are important mediators of
environment-behaviour connections. Bandura’s early research focused heavily on
observational learning, learning that occurs through observing what others do.
Observational learning is also referred to as imitation or modelling. Bandura
(1925–) believes that people cognitively represent the behaviour of others and then
sometimes adopt this behaviour themselves. For example, a young boy might
observe his father’s aggressive outbursts and hostile interchanges with people; when
observed with his peers, the young boy’s style of interaction is highly aggressive,
showing the same characteristics as his father’s behaviour. Social cognitive theorists
believe that people acquire a wide range of such behaviours, thoughts, and feelings
through observing others’ behaviour. These observations form an important part of
life-span development.
Developmental Psychology (Paper I) Page 17 School of Distance Education An Eclectic Theoretical Orientation
An eclectic theoretical orientation does not follow any one theoretical
approach but, rather, selects and uses from each theory whatever is considered the
best in it. No single theory described in this chapter is indomitable or capable of
explaining entirely the rich complexity of life-span development. Each of the theories
has made important contributions to our understanding of development, but none
provides a complete description and explanation. Psychoanalytic theory best
explains the unconscious mind. Erikson’s theory best describes the changes that
occur in adult development.
Piaget’s, Vygotsky’s, and the information-processing views provide the most
complete description of cognitive development. The behavioural and social cognitive
and ecological theories have been the most adept at examining the environmental
determinants of development.
Developmental Psychology (Paper I) Page 18 School of Distance Education MODULE 2
PRENATAL PERIOD
Prenatal Development begins at conception. Ovum is largest cell in the body, sperm
is one of the smallest. Conception occurs when an egg has erupted from the ovary
(as it will every 28 days) and is fertilized in the fallopian tubes or womb. Hormones
are released to prepare the lining of the womb for implantation of the zygote. If there
are abnormalities or faulty implantation, zygote will be shed 2 weeks later with
menstrual flow with the mother never knowing she was pregnant. Sperm live for 6
days in the woman’s environment, but the egg only lasts 1 day after entering the
fallopian tube. Most pregnancies occur within 3 days around ovulation. The process
of prenatal development occurs in three main stages. The first two weeks after
conception are known as the germinal stage; the third through the eighth week are
known as the embryonic period; and the time from the ninth week until birth is
known as the fetal period.
The Germinal Stage: The germinal stage begins with conception, when the sperm
and egg cell unite in one of the two fallopian tubes. The fertilized egg, known as a
zygote then moves toward the uterus, a journey that can take up to a week to
complete. Cell division begins approximately 24 to 36 hours after conception. Within
just a few hours after conception, the singe-celled zygote begins making a journey
down the fallopian tube to the uterus where it will begin the process of cell division
and growth. The zygote first divides into two cells, then into four, eight, sixteen, and
so on. Once the eight cell point has been reached, the cells begin to differentiate and
take on certain characteristics that will determine the type of cells they will
eventually become. As the cells multiply, they will also separate into two distinctive
masses: the outer cells will eventually become the placenta while the inner cells will
form the embryo. Cell division continues at a rapid rate and the cells then develop
into what is known as a blastocyst. The blastocyst is made up of three laters:
1. The ectoderm (which will become the skin and nervous system)
2. The endoderm (which will become the digestive and respiratory systems)
3. The mesoderm (which will become the muscle and skeletal systems).
Developmental Psychology (Paper I) Page 19 School of Distance Education Finally, the blast cyst arrives at the uterus and attached to the uterine wall, a
process known as implantation. Implantation occurs when the cells nestle into the
uterine lining and rupture tiny blood vessels. The connective web of blood vessels
and membranes that forms between them will provide nourishment for the
developing being for the next nine months. Implantation is not always an automatic
and sure-fire process. Researchers estimate that approximately 58 percent of all
natural conceptions never become properly implanted in the uterus, which results in
the new life ending before the mother is ever aware she is pregnant.
When implantation is successful, hormonal changes halt a woman’s normal
menstrual cycle and cause a whole host of physical changes. For some women,
activities they previously enjoyed such as smoking and drinking alcohol or coffee
may become less palatable, possibly part of nature’s way of protecting the growing
life inside her.
The Embryonic Stage:
The mass of cells is now know as and embryo. The
beginning of the third week after conception marks the start of the embryonic period,
a time when the mass of cells becomes a distinct human being. The embryo begins to
divide into three layers each of which will become an important body system.
Approximately 22 days after conception, the neural tube forms. This tube will later
develop into the central nervous system including the spinal cord and brain. Around
the fourth week, the head begins to form quickly followed by the eyes, nose, ears,
and mouth. The cardiovascular system is where the earliest activity begins as the
blood vessel that will become the heart start to pulse. During the fifth week, buds
that will form the arms and legs appear. By the time the eight week of development
has been reached, the embryo has all of the basic organs and parts except those of the
sex organs. It even has knees and elbows! At this point, the embryo weight just one
gram and is about one inch in length.
The Fetal Stage: Once cell differentiation is mostly complete, the embryo enters the
next stage and becomes known as a fetus. This period of develop begins during the
ninth week and lasts until birth. The early body systems and structures established in
the embryonic stage continue to develop. The neural tube develops into the brain
and spinal cord and neurons form. Sex organs begin to appear during the third
month of gestation. The fetus continues to grow in both weight and length, although
the majority of the physical growth occurs in the later stages of pregnancy. This
stage of prenatal development lasts the longest and is marked by amazing change
and growth. During the third month of gestation, the sex organs begin to
differentiate and by the end of the month all parts of the body will be formed. At this
point, the fetus weight around three ounces.
Developmental Psychology (Paper I) Page 20 School of Distance Education The end of the third month also marks the end of the first trimester of
pregnancy. During the second trimester, or months four through six, the heartbeat
grows stronger and other body systems become further developed. Fingernails, hair,
eyelashes and toenails form. Perhaps most noticeably, the fetus increases quite
dramatically in size, increasing about six times in size. The brain and central nervous
system also become responsive during the second trimester. Around 28 weeks, the
brain starts to mature much faster with activity that greatly resembles that of a
sleeping newborn. During period from seven months until birth, the fetus continues
to develop, put on weight, and prepare for life outside the womb. The lungs begin to
expand and contract, preparing the muscles for breathing.
EFFECTS OF TERATOGENS
Teratogens are environmental agents that can cause damage to the developing
fetus. Later in development, exposure to these agents may do little harm. Recognition
of human teratogens offers the opportunity to prevent exposure at critical periods of
development and prevent certain types of congenital malformations. In general,
drugs, food additives, and pesticides are tested to determine their teratogenicity to
minimize exposure of pregnant women to teratogenic agents. To prove that a specific
agent is teratogenic means to prove that the frequency of congenital malformations
in women exposed to the agent is prospectively greater than the background
frequency in the general population
TYPES OF TERATOGENS
o Drugs, even prescription drugs, can have impacts on development. Any drug
taken by the mother that has a molecule small enough to penetrate the
placental barrier can affect the fetus. Even aspirin can relate to low birth
weight, increased mortality, lower IQ and poorer motor development. Even
caffeine links to low birth weight, miscarriage, withdrawal symptoms in the
baby such as irritability, vomiting.
ƒ
Prescription- This was tragically seen with thalidomide, used to
sedate mothers, but producing gross deformities in limbs, ears, heart,
kidneys, & genitals.
ƒ
Illegal drugs
•
Cocaine produces drug-addicted babies with multiple problemsprematurity, low birth weight, defects, breathing problems,
death at birth. There are affects to the blood vessels and
Developmental Psychology (Paper I) Page 21 School of Distance Education oxygenation of the baby after a dose, which can permanently
affect neural development. Motor and language functions are
affected.
•
Marijuana relates to low birth weight, prematurity.
•
Heroin/ methadone produces addicted babies, less responsive,
with poor motor development.
o Smoking exposes babies to tobacco and produces low birth weight,
miscarriage, impaired breathing, greater mortality risk, cancer later in
childhood. It also puts the mother at increased risk of bleeding. These babies
seem to have shorter attention spans, poorer memories, lower IQ scores and
more behavior problems later. Nicotine constricts blood vessels, so nutrients
and oxygen are in shorter supply to the baby. Also it increases carbon
monoxide in the baby’s blood. That affects CNS development. Even passive
smoke exposure affects the baby.
o Alcohol is the single greatest cause of birth defects and is completely
preventable. The effects on the baby are permanent, even if the baby gets a
rich environment after birth. The brain is permanently affected in structure
and function. The brain simply did not get enough oxygen to develop. Even
one drink per day has affects on fetal development and growth.
ƒ
Fetal alcohol syndrome (FAS) is the severe form of the impairments
due to mother’s drinking. It shows as mental retardation, impaired
coordination, attention problems, impaired memory and language,
hyperactivity. There are particular facial abnormalities and small
skull and brain.
ƒ
Fetal alcohol effects (FAE) is a milder form yet there are significant
impairments in learning potential.
o Radiation effects were clearly seen after Hiroshima, Chernobyl. A great many
babies miscarried, others were born with underdeveloped brains, deformities,
slow growth patterns. There may be heightened risk to the baby of childhood
cancer, lower IQs, learning and emotional disorders.
o Pollution
ƒ
Mercury- effects of exposure are physical deformities, mental
retardation, speech impairments, motor problems.
Developmental Psychology (Paper I) Page 22 School of Distance Education ƒ
Lead – effects are prematurity, low birth weight, brain damage,
physical defects.
o Infectious diseases
ƒ
Rubella – German measles in the mother during sensitive periods in
fetal development results in heart defects, eye cataracts, deafness,
internal abnormalities, mental retardation.
ƒ
HIV & AIDS is passed to a fetus 20 – 30% of the time. It causes
weight loss, diarrhea, respiratory illness, brain damage. Most babies
survive only 5 – 8 months once symptoms appear. If the mother uses
AZT, it reduces transmission to the baby 95%. Unfortunately, in
Africa, most clinics have no access to these life-saving drugs, so
babies are born infected and soon die.
ƒ
Herpes results in infection of baby during birth, miscarriage, low
birth weight, malformations, mental retardation.
ƒ
Toxoplasmosis is contracted from cat feces or undercooked meat. If
the baby is exposed during a critical period, it can cause brain and eye
damage.
.Other maternal factors
o Nutrition- during a healthy pregnancy, mom will gain about 25-30 pounds. If
the baby is malnourished, there is serious damage to the CNS, seen in lower
brain weight. It will also affect other organ system development, especially the
immune system, resulting in frequent illness. Lack of folic acid particularly
affects neural tube formation, showing up as anencephaly or spina bifida.
o Stress relates to miscarriage, prematurity, low birth weight and baby
irritability, respiratory illness, GI tract problems. It also relates to cleft palate
and pyloric stenosis which affects nutritional intake. Stress hormones shift
blood flow from the body to the brain and reduces oxygenation. Stress also
affects immunity, increasing illness.
o Rh Factor Incompatibility occurs when the mother is Rh-negative but the
baby is Rh-positive. The mother’s body will form antibodies to fight the
foreign blood protein being produced by the baby. It can reduce oxygenation
to the baby. First babies are usually not affected, but the risk occurs to later
pregnancies. There is a vaccine given to the mother of a positive baby to
Developmental Psychology (Paper I) Page 23 School of Distance Education prevent buildup of antibodies. Blood transfusions may be necessary after
birth.
o Maternal age/ previous births can affect ability to get pregnant or chances of
having a baby with chromosomal defects (Downs syndrome) but other
complications are no more prevalent in older mothers.
o Drugs, even prescription drugs, can have impacts on development. Any drug
taken by the mother that has a molecule small enough to penetrate the
placental barrier can affect the fetus. Even aspirin can relate to low birth
weight, increased mortality, lower IQ and poorer motor development. Even
caffeine links to low birth weight, miscarriage, withdrawal symptoms in the
baby such as irritability, vomiting.
ƒ
Prescription- This was tragically seen with thalidomide, used to
sedate mothers, but producing gross deformities in limbs, ears, heart,
kidneys, & genitals.
ƒ
Illegal drugs
•
Cocaine produces drug-addicted babies with multiple
problems- prematurity, low birth weight, defects, breathing
problems, death at birth. These babies cry is so shrill that it
affects the caregivers. It may devolve into attachment
problems if the mother can’t care for the infant adequately.
There are affects to the blood vessels and oxygenation of the
baby after a dose, which can permanently affect neural
development. Motor and language functions are affected.
Crack babies have the most serious problems. Unfortunately
these babies’ problems don’t end with birth, since their
mothers are usually unable to adequately care for them.
•
Marijuana relates to low birth weight, prematurity.
•
Heroin/ methadone produces addicted
responsive, with poor motor development.
babies,
less
o Smoking exposes babies to tobacco and produces low birth weight,
miscarriage, impaired breathing, greater mortality risk, cancer later in
childhood. It also puts the mother at increased risk of bleeding. These babies
seem to have shorter attention spans, poorer memories, lower IQ scores and
Developmental Psychology (Paper I) Page 24 School of Distance Education more behavior problems later. Nicotine constricts blood vessels, so nutrients
and oxygen are in shorter supply to the baby. Also it increases carbon
monoxide in the baby’s blood. That affects CNS development. Even passive
smoke exposure affects the baby.
o Alcohol is the single greatest cause of birth defects and is completely
preventable. The effects on the baby are permanent, even if the baby gets a
rich environment after birth. The brain is permanently affected in structure
and function. The brain simply did not get enough oxygen to develop. Even
one drink per day has affects on fetal development and growth.
ƒ
Fetal alcohol syndrome (FAS) is the severe form of the impairments
due to mother’s drinking. It shows as mental retardation, impaired
coordination, attention problems, impaired memory and language,
hyperactivity. There are particular facial abnormalities and small
skull and brain.
ƒ
Fetal alcohol effects (FAE) is a milder form yet there are significant
impairments in learning potential.
o Radiation effects were clearly seen after Hiroshima, Chernobyl. A great many
babies miscarried, others were born with underdeveloped brains, deformities,
slow growth patterns. There may be heightened risk to the baby of childhood
cancer, lower IQs, learning and emotional disorders.
o Pollution
ƒ
Mercury- effects of exposure are physical deformities, mental
retardation, speech impairments, motor problems.
ƒ
Lead – effects are prematurity, low birth weight, brain damage,
physical defects.
ƒ
PCBs- low birth weight, discolored skin, deformities of gums, nails,
brain waves, poor cognitive development.
o Infectious diseases
ƒ
Rubella – German measles in the mother during sensitive periods in
fetal development results in heart defects, eye cataracts, deafness,
internal abnormalities, mental retardation.
Developmental Psychology (Paper I) Page 25 School of Distance Education ƒ
HIV & AIDS is passed to a fetus 20 – 30% of the time. It causes
weight loss, diarrhea, respiratory illness, brain damage. Most babies
survive only 5 – 8 months once symptoms appear. If the mother uses
AZT, it reduces transmission to the baby 95%. Unfortunately, in
Africa, most clinics have no access to these life-saving drugs, so
babies are born infected and soon die.
ƒ
Herpes results in infection of baby during birth, miscarriage, low
birth weight, malformations, mental retardation.
ƒ
Toxoplasmosis is contracted from cat feces or undercooked meat. If
the baby is exposed during a critical period, it can cause brain and eye
damage.
• Prenatal Environment and later health
o Low birth weight and CVD- infant’s poor weight gain results in
cardiovascular disease in adulthood. Poor nutrition can also result in
diabetes by affecting pancreas function. Stress hormones from the mother
may also retard fetal growth, increase blood pressure and produce
hypoglycemia. Low weight gain often is compensated by later weight gain
that predisposes to diabetes.
o High birth weight and breast cancer – high birth weight in babies relates to
later breast cancer. It seems to be due to high levels of estrogen during
pregnancy which affects breast tissue development.
o Prevention occurs as we care for our health in a thoughtful way as we have
control over eating, exercise, preventive medicine.
• Other maternal factors
o Nutrition- during a healthy pregnancy, mom will gain about 25-30 pounds.
If the baby is malnourished, there is serious damage to the CNS, seen in
lower brain weight. It will also affect other organ system development,
especially the immune system, resulting in frequent illness. Lack of folic acid
particularly affects neural tube formation, showing up as anencephaly or
spina bifida.
o Stress relates to miscarriage, prematurity, low birth weight and baby
irritability, respiratory illness, GI tract problems. It also relates to cleft palate
and pyloric stenosis which affects nutritional intake. Stress hormones shift
Developmental Psychology (Paper I) Page 26 School of Distance Education blood flow from the body to the brain and reduces oxygenation. Stress also
affects immunity, increasing illness.
o Rh Factor Incompatibility occurs when the mother is Rh-negative but the
baby is Rh-positive. The mother’s body will form antibodies to fight the
foreign blood protein being produced by the baby. It can reduce oxygenation
to the baby. First babies are usually not affected, but the risk occurs to later
pregnancies. There is a vaccine given to the mother of a positive baby to
prevent buildup of antibodies. Blood transfusions may be necessary after
birth.
o Maternal age/ previous births can affect ability to get pregnant or chances of
having a baby with chromosomal defects (Downs syndrome) but other
complications are no more prevalent in older mothers.
PRENATAL DIAGNOSTIC METHODS
Amniocentesis: The most widely used technique, A hollow needle is inserted
through the abdominal wall to obtain a sample of fluid in the uterus. Cells are
examined for genetic defects. Can be performed by the fourteenth week after
conception; 1 to 2 more weeks are required for test results. Small risk of miscarriage.
Chorionic villus sampling: A procedure that can be used if results are
desired or needed very early in pregnancy. A thin tube be inserted into the uterus
through the vagina, or a hollow needle is inserted through the abdominal wall. A
small plug of tissue is removed from the end of one or more chorionic villi, the
hairlike projections on the membrane surrounding the developing organism. Cells
are examined for genetic defects. Can be performed by the ninth week after
conception, and results are available within 24 hours. Entails a slightly greater risk of
miscarriage than amniocentesis. Also associated with a small risk of limb
deformities, which increases the earlier the procedure is performed.
Fetoscopy: A small tube with a light source at one end is inserted into the
uterus to inspect the fetus for defects of the limbs and face. Also sample of fetal
blood to be obtained, permitting diagnosis of such disorders as hemophilia and sickle
cell anemia, as well as neural defects (see below). Usually performed between 15 and
18 weeks after conception, but can be done as early as 5 weeks. Entails some risk of
miscarriage.
Developmental Psychology (Paper I) Page 27 School of Distance Education Ultrasound: High-frequency sound waves are beamed at the uterus; their
reflection is translated into a picture on a video screen that reveals the size, the shape,
and placement of the fetus. By itself, permits assessment of fetal age, detection of
multiple pregnancies, and identification of gross physical defects. Also used to guide
amniocentesis, chorionic villus sampling, and fetoscopy. When used five or more
times, may increase the chances of low birth weight.
Maternal blood analysis: By the second month of pregnancy, some of the
developing organism’s cells enter the maternal bloodstream. An elevated level of
alpha-fetoprotein may indicate kidney disease, abnormal closure of the esophagus,
or neural tube defects, such as anencephaly (absence of most of the brain) and spina
bifida (bulging of the spinal cord from the spinal column). Isolated cells can be
examined for genetic defects, such as Down syndrome.
Preimplantation genetic diagnosis:
After in vitro fertilization and
duplication of the zygote into a cluster of about eight cells, one cell is removed and
examined for hereditary defects. Only if that cell is free of detectable genetic
disorders is the fertilized ovum implanted in the woman’s uterus. Permits parents at
high risk of bearing offspring with a genetic disorder and women of advanced
childbearing age to avoid implantation of most abnormal embryos.
NEONATAL HEALTH AND RESPONSIVENESS
After the baby and mother have met and acquainted, the new born is cleaned,
examined, weighed and evaluated. A surprisingly large number of babies are born
with problems because of what may look like a trivial fact: their birth weight is low.
LOW BIRTH WEIGHT INFANTS
A low birth weight infant weighs less than 51⁄2 pounds at birth. Two
subgroups are those that are very low birth weight (under 3 pounds) and extremely
low birth weight (under 2 pounds) (Horbar & others, 2001). Low birth weight babies
may be preterm or simply small for their date of birth.
Preterm and Small for Date Infants
Preterm infants are those born three weeks or more before the pregnancy has
reached its full term. This means that the term “preterm” is given to an infant who is
born at 35 or less weeks after conception. Most preterm babies are also low birth
weight babies. A short gestation period does not necessarily harm an infant. It is
distinguished from retarded prenatal growth, in which the fetus has been damaged
Developmental Psychology (Paper I) Page 28 School of Distance Education (Kopp, 1992). The neurological development of a preterm baby continues after birth
on approximately the same timetable as if the infant still were in the womb. For
example, consider a preterm baby born 30 weeks after conception. At 38 weeks,
approximately two months after birth, this infant shows the same level of brain
development as a 38-week fetus who is yet to be born.
Small for date infants (also called small for gestational age infants) are those
whose birth weight is below normal when the length of pregnancy is considered.
Small for date infants may be preterm or full term. They weigh less than 90 percent
of all babies of the same gestational age. Inadequate nutrition and smoking by the
pregnant woman are among the main factors in producing small for date infants.
Long-Term Outcomes for Low Birth Weight Infants
Although most low birth weight infants are normal and healthy, as a group
they have more health and developmental problems than normal birth weight
infants (Chescheir & Hansen, 1999; Hack, Klein, & Taylor, 1995). The number and
severity of these problems increase as birth weight decreases (Lemons & others, 2001;
Tommiska & others, 2001). With the improved survival rates for infants who are born
very early and very small come increases in severe brain damage. Cerebral palsy and
other forms of brain injury are highly correlated with brain weight—the lower the
brain weight, the greater the likelihood of brain injury. Approximately 7 percent of
moderately low birth weight infants (3 pounds 5 ounces to 5 pounds 8 ounces) have
brain injuries. This figure increases to 20 percent for the smallest newborns (1 pound
2 ounces to 3 pounds 5 ounces). Low birth weight infants are also more likely than
normal birth weight infants to have lung or liver diseases. At school age, children
who were born low in birth weight are more likely than their normal birth weight
counterparts to have a learning disability, attention deficit disorder, or breathing
problems, such as asthma (Taylor, Klein, & Hack, 1994).
Children born very low in birth weight have more learning problems and
lower levels of achievement in reading and math than moderately low birth weight
children. These problems are reflected in much higher percentages of low birth
weight children being enrolled in special education programs. Approximately 50
percent of all low birth weight children are enrolled in special education programs.
Not all of these adverse consequences can be attributed solely to being born low in
birth weight. Some of the less severe but more common developmental and physical
delays occur because many low birth weight children come from disadvantaged
environment. Some of the devastating effects of being born low in birth weight can
be reversed.
Developmental Psychology (Paper I) Page 29 School of Distance Education Intensive enrichment programs that provide medical and educational services
for both the parents and the child have been shown to improve short-term
developmental outcomes for low birth weight children (Kleberg, Westrup, &
Stjernquist, 2000). Federal laws mandate that services for school-age disabled
children (which include medical, educational, psychological, occupational, and
physical care) be expanded to include family-based care for infants. At present, these
services are aimed at children born with severe congenital disabilities. The
availability of services for moderately low birth weight children who do not have
severe physical problems varies from state to state, but generally these services are
not available.
Developmental Psychology (Paper I) Page 30 School of Distance Education MODULE.3
PHYSICAL DEVELOPMENT AND AGING
Patterns of growth
Cephalocaudal and Proximodistal pattern
Cephalocaudal: There are two general patterns of physical growth. The first
consists of development starting at the top of the body and working its way down,
i.e., from the head to the feet. This is called the cephalocaudal pattern of
development. What this means is that the development of the head and brain tends
to be more advanced (in the sense that it occurs first) than the rest of the body. This is
evident from very early in development and characterizes the development of
human children. The cephalocaudal pattern of development is most pronounced
during the prenatal period (when the head may make up more than half of the baby's
length), decreases by birth (when the head comprises about 25% of the neonate's
body length), and gradually reaches adult levels by adolescence (when the head
comprises about 10% of the body's length). This pattern is largely complete by the
beginning of adulthood, though of course other aspects of development continues
throughout life.
Proximodistal: The second general pattern of physical growth consists in the
tendency for growth to start at the center of the body and work its way outward,
toward the extremities. This is called the proximodistal pattern. Thus, the head and
trunk of the body develop (grow) first, followed by the arms and legs. This means
that the spinal cord develops before outer parts of the body. The child's arms
develop before the hands and the hands and feet develop before the fingers and
toes. Finger and toe muscles (used in fine motor dexterity) are the last to develop in
physical development.
NEW BORN REFLEXES
Babies are born with certain reflexes. Reflexes govern the newborn's movement
which are automatic and out of the newborn's control. Reflexes are genetically
carried and designed to enhance the baby's chance of survival. Below is a chart
describing the various reflexes and how long the reflex last.
Developmental Psychology (Paper I) Page 31 School of Distance Education Infants Response
Development
Patterns
Reflex
Stimulation
Blinking
Flash of light puff
Closes both eyes
of air
Babinski
Stroke sole of foot
Moro
Arches
back
and
Loud noise, being
Disappears after 3 to
throws out arms and
dropped
4 months
legs, then closes
Permanent
Twists foot, fans out Disappears
9
toes
months to one year
Grasping
Palms touched
Rooting
Cheeks stroked Turns head, opens
Disappears after 3
or side of mouth mouth and begins
to 4 months
touched
sucking
Stepping
Infants
held
above
surface Moves feet as if to Disappears after 3
and feet lowered walk
to 4 months
to touch surface
Sucking
Object touching
Disappears after 3
Sucks automatically
mouth
to 4 months
Swimming
Makes coordinating
Infant put face
Disappears after 6
swimming
down in water
to 7 months
movements
Tonic Neck
Forms fist with
Infant placed on
Disappears after 2
hands and makes a
back
months
"fencers" pose
Developmental Psychology (Paper I) Grasp tightly
Weakens after 3
months, disappears
after 1 year
Page 32 School of Distance Education PERCEPTION OF NEW BORN INFANT
Infant Perception: Infants respond to stimuli differently in these different states.
•
Vision is significantly worse in infants than in older children. Infant sight,
blurry in early stages, improves over time. Color perception similar to that
seen in adults has been demonstrated in infants as young as four months,
using habituation methods. Infants get to adult-like vision in about six
months.
•
Hearing is well-developed prior to birth, however. Newborns prefer complex
sounds to pure tones, human speech to other sounds, mother's voice to other
voices, and the native language to other languages. These are probably
learned in the womb. Infants are fairly good at detecting the direction from
which a sound comes, and by 18 months their hearing ability is approximately
equal to that of adults.
•
Smell and taste are present, with infants showing different expressions of
disgust or pleasure when presented with pleasant odors (honey, milk, etc.) or
unpleasant odors (rotten egg) and tastes (e.g. sour taste). Newborns are born
with odor and taste preferences acquired in the womb from the smell and
taste of amniotic fluid, in turn influenced by what the mother eats. Both
breast- and bottle-fed babies around 3 days old prefer the smell of human milk
to that of formula, indicating an innate preference. There is good evidence for
older infants preferring the smell of their mother to that of others.
•
Touch is one of the better-developed senses at birth, being one of the first to
develop inside the womb. This is evidenced by the primitive reflexes
described above, and the relatively advanced development of the
somatosensory cortex.
•
Pain: Infants feel pain similarly, if not more strongly than older children but
pain-relief in infants has not received so much attention as an area of research.
HEIGHT AND WEIGHT IN INFANCY AND CHILDHOOD
Height and weight increase rapidly in infancy. Then they take a slower course
during the childhood years.
Developmental Psychology (Paper I) Page 33 School of Distance Education Infancy: The average new born in 20 inches long and weighs 7-1/2 pounds.
A 95% of full term new borns are 18 to 22 inches long and weigh between 5-1/2 and
10 pounds. In the first several days if life, most new born slows 5% to 7% of their
body weight. Once infants adjust to sucking, swallowing, and digesting, they grow
rapidly, gaining an average of 5 to 6 ounces per week during the first month. Infant’s
rate of growth is considerably slower in the second year of life. By two years of age,
infants weigh approximately 26 to 32 pounds, having gained a quarter to half a
pound per month during the second year; now they have reached about one-fifth of
their adult weight. The average two year old is 30 to 35 inches tall, which is nearly
one half of adult height.
Early childhood: Girls are only slightly smaller and lighter than boys during
these years. Both boys and girls slim down as the trunks of their bodies lengthen.
Although, their heads are still, somewhat large for their bodies, by the end of preschool years most children have lost their top heavy look. A review of the height and
weight of children around the world concluded that two important contributors to
height differences are ethnic origin and nutrition. The children whose mothers
smoke during pregnancy are half an inch shorter than the children whose mothers
did not smoke during pregnancy.
Middle and late childhood: The period of middle and late childhood
involves slow, consistent growth. This is a period of calm before the rapid growth
spurt of adolescence. During the elementary school years, children grown an
average of 2 to 3 inches a year. At the age of 8 the average girl and average boy are 4
feet 2 inches tall and body weigh 56 pounds. Muscle mass and strength gradually
increase as “baby fat,” decreases in middle and late childhood. Head circumference,
waist circumference, and leg length decrease in relation to body weight. A less
noticeable physical change is that bones continue to harden during middle and late
childhood, but yield to pressure an pull more than mature bones.
Early Childhood Physical Development: Gross and Fine Motor Development
The term "gross motor" development refers to physical skills that use large
body movements, normally involving the entire body. In the sense used here, gross
means "large" rather than "disgusting."
Between ages 2 and 3 years, young children stop "toddling," or using the
awkward, wide-legged robot-like stance that is the hallmark of new walkers. As they
develop a smoother gait, they also develop the ability to run, jump, and hop.
Children of this age can participate in throwing and catching games with larger balls.
They can also push themselves around with their feet while sitting on a riding toy.
Developmental Psychology (Paper I) Page 34 School of Distance Education By ages 3 to 4 , children develop better upper body mobility. As a result, their
catching and throwing abilities improve in speed and accuracy. In addition, they can
typically hit a stationary ball from a tee with a bat. As whole body coordination
improves, children of this age can now peddle and steer a tricycle. They can also kick
a larger ball placed directly in front of their bodies.
During ages 5 to 6, young children continue to refine earlier skills. They're
running even faster and can start to ride bicycles with training wheels for added
stability. In addition, they can step sideways. Children of this age begin mastering
new forms of physical play such as the jungle gym, and begin to use the see-saw,
slide, and swing on their own. They often start jumping rope, skating, hitting balls
with bats, and so on. Many children of this age enjoy learning to play organized
sports such as soccer, basketball, t-ball or swimming. In addition, 5 to 6 year olds
often like to participate in physical extracurricular activities such as karate,
gymnastics, or dance. Children continue to refine and improve their gross motor
skills through age 7 and beyond.
Physical Development: Fine Motor Skills
Fine motor skills are necessary to engage in smaller, more precise movements,
normally using the hands and fingers. Fine motor skills are different than gross
motor skills which require less precision to perform.
By ages 2 to 3 years, children can create things with their hands. They can
build towers out of blocks, mold clay into rough shapes, and scribble with a crayon
or pen. Children of this age can also insert objects into matching spaces, such as
placing round pegs into round holes. 2 to 3 year-olds often begin showing a
preference for using one hand more often than the other, which is the beginning of
becoming left or right-handed.
Around ages 3 to 4 years, children start to manipulate clothing fasteners, like
zippers and snaps, and continue to gain independence in dressing and undressing
themselves. Before they enter school, most children will gain the ability to completely
dress and undress themselves (even though they may take a long time to finish the
task). At this age, children can also begin using scissors to cut paper. Caregivers
should be sure to give children blunt, round-edged "kid" scissors for safety reasons!
3 to 4 year- olds continue to refine their eating skills and can use utensils like
forks and spoons. Young children at this age can also use larger writing instruments,
like fat crayons, in a writing hold rather than just grasping them with their fist. They
can also use a twisting motion with their hands, useful for opening door knobs or
Developmental Psychology (Paper I) Page 35 School of Distance Education twisting lids off containers. Because children can now open containers with lids,
caregivers should make certain that harmful substances such as cleaners and
medications are stored out of reach in a locked area to prevent accidental poisonings.
5-7 year-olds begin to show the skills necessary for starting or succeeding in
school, such as printing letters and numbers and creating shapes such as triangles.
They are able to use paints, pencils and crayons with better control. Children can also
complete other self-care tasks beyond dressing and undressing, such as brushing
their teeth and combing their hair. Children of this age can also independently feed
themselves without an adult's immediate supervision or help.
HANDEDNESS
Lateralization and Handedness: Research on handedness supports the joint
contribution of nature and nurture to brain lateralization. As early as the tenth
prenatal week, most fetuses show a right-hand preference during thumb-sucking
(Hepper, McCartney, & Shannon, 1998). And by age 6 months, infants typically reach
more smoothly and efficiently with their right than their left arm. These tendencies,
believed to be biologically based, may contribute to the right-handed bias of most
children by the end of the first year (Hinojosa, Sheu, & Michel, 2003; Rönnqvist &
Domellöf, 2006). During toddlerhood and early childhood, handedness gradually
extends to a wider range of skills. Handedness reflects the greater capacity of one
side of the brain—the individuals.
Dominant cerebral hemisphere —to carry out skilled motor action. Other
important abilities are generally located on the dominant side as well. For righthanded people—in Western nations, 90 percent of the population—language is
housed in the left hemisphere with hand control. For the left-handed 10 percent,
language is occasionally located in the right hemisphere or, more often, shared
between the hemispheres (Perelle & Ehrman, 2009). This indicates that the brains of
left-handers tend to be less strongly lateralized than those of right-handers. Lefthanded parents show only a weak tendency to have left-handed children
(Vuoksimaa et al., 2009). One genetic theory proposes that most children inherit a
gene that biases them for right-handedness and a left-dominant cerebral hemisphere.
But that bias is not strong enough to overcome experiences that might sway children
toward a left-hand preference (Annett, 2002). Even prenatal events may profoundly
affect handedness. Both identical and fraternal twins are more likely than ordinary
siblings to differ in hand preference, probably because twins usually lie in opposite
orientations in the uterus (Derom et al., 1996). The orientation of most singleton
fetuses—facing toward the left—is believed to promote greater control over
Developmental Psychology (Paper I) Page 36 School of Distance Education movements on the body’s right side (Previc, 1991). Handedness also involves
practice. It is strongest for complex skills requiring extensive training, such as eating
with utensils, writing, and engaging in athletic activities. And wide cultural
differences exist: In Tanzania, Africa, where children are physically restrained and
punished for favoring the left hand, less than 1 percent of adults are left-handed
(Provins, 1997). Although rates of left-handedness are elevated among people with
mental retardation and mental illness, atypical brain lateralization is probably not
responsible for these individuals’ problems. Rather, early damage to the left
hemisphere may have caused their disabilities while also leading to a shift in
handedness. In support of this idea, left-handedness is associated with prenatal and
birth difficulties that can result in brain damage, including prolonged labor,
prematurity, and Rh incompatibility (Powls et al., 1996; Rodriguez & Waldenström,
2008).
Most left-handers, however, have no developmental problems—in fact,
unusual lateralization may have certain advantages. Left- and mixed-handed young
people are slightly advantaged in speed and flexibility of thinking, and they are more
likely than their righthanded agemates to develop outstanding verbal and
mathematical talents (Flannery & Liederman, 1995; Gunstad et al., 2007). More even
distribution of cognitive functions across both hemispheres may be responsible.
Physical development in puberty
Puberty is the time of rapid physical development, signaling the end of
childhood and the beginning of sexual maturity. Although puberty may begin at
different times for different people, by its completion girls and boys without any
developmental problems will be structurally and hormonally prepared for sexual
reproduction. The speed at which adolescents sexually mature varies; the beginning
of puberty in both genders falls within a range of 6 to 7 years. In any grouping of 14year-olds, for example, one is likely to see teenagers in assorted stages of
development—some appearing as older children and others as fully mature
adolescents. Eventually, though, everyone catches up.
Hormones are responsible for the development of both primary sex
characteristics (structures directly responsible for reproduction) and secondary sex
characteristics (structures indirectly responsible for reproduction). Examples of
primary sex characteristics are the penis in boys and the uterus in females. An
example of secondary sex characteristics is the growth of pubic hair in both genders.
During childhood, males and females produce roughly equal amounts of male
(androgen) and female (estrogen) hormones. At the onset of puberty, the pituitary
Developmental Psychology (Paper I) Page 37 School of Distance Education gland stimulates hormonal changes throughout the body, including in the adrenal,
endocrine, and sexual glands. The timing of puberty seems to result from a
combination of genetic, environmental, and health factors.
An early sign of maturation is the adolescent growth spurt, or a noticeable
increase in height and weight. The female growth spurt usually begins between ages
10 and 14, and ends by age 16. The male growth spurt usually begins between ages
10 and 16, and ends by age 18.
Girls generally begin puberty a few years earlier than boys, somewhere
around ages 11 to 12. Increasing levels of estrogen trigger the onset of puberty in
girls. They grow taller; their hips widen; their breasts become rounder and larger;
hair grows on the legs, under the arms, and around the genitals; the labia thicken; the
clitoris elongates; and the uterus enlarges. Around the age of 12 or 13, most girls
today begin menstruating, or having menstrual periods and flow. The onset of
menstruation is termed menarche.
CHANGES IN EARLY,MIDDLE AND LATE ADULTHOOD
EARLY ADULTHOOD
After the dramatic physical changes or puberty, the years of early adulthood
seem an uneventful time in the body’s history. Height remains rather constant
during the early adulthood years. Peak functioning of the body’s joint also usually
occurs in the 20s. Many individuals also reach a peak of muscle tone and strength in
their late teens and 20s. However, these may begin to decline in the 30s. Sagging
chins and protruding abdomens may also appear for the first time. Muscles start to
have less elasticity, and aches may begin to show in places not felt before.
MIDDLE ADULTHOOD
Although everyone experiences some physical change due to aging in the
middle adulthood years, the rates of aging vary considerably from one individual to
another. Middle aged individuals lose height, and many gain weight. Noticeable
signs of aging usually are apparent by the 40s or 50s. The skin begins to wrinkle and
sag because of a loss of fat and collagen in underlying tissues. The hair thins and
grays due to a lower replacement rate and a decline in melanin production. Finger
nails and toe nails develop ridges and become thicker and more brittle. The
maximum bone density occurs by the mid to late 30s. From this point on, there is a
progressive loss of bone. By the end of midlife, bones break more easily and heal
Developmental Psychology (Paper I) Page 38 School of Distance Education more slowly. The level of cholesterol in the blood increase through the adult years.
Blood pressure too usually rises in the 40s and 50s. An increasing problem in middle
and late adulthood that involves the cardiovascular system is metabolic disorder, a
condition characterized by hypertension, obesity, and insulin resistance. There is a
little change in lung capacity through most of middle adulthood\. However, at
above the age of 55, the proteins in lung tissue become less elastic.
LATE ADULTHOOD
Late adulthood brings an increased risk of physical disability, but there is
considerable variability in rates of decline in functioning. The physical performance
of older adults in poor health from low income backgrounds was inferior to that of
their higher income, healthy counterparts. The changes in physical appearance that
take place in middle adulthood become more pronounced in late adulthood. Most
noticeable are facial wrinkles and age spots. Significant changes also take place in
the circulatory system of older adults. A rise on blood pressure with age should be
treated to reduce the risk of heart attack, stroke, or kidney disease.
Certainly, the decline of abilities that were once taken for granted can lead to a
reduced sense of competence for the older person (Whitbourne, 2001). And the
curtailment of activities that were previously enjoyed can affect people’s assessment
of their quality of life. But, once again, the extent of the impact of biological decline
varies from person to person, and is influenced by both the rate of change and the
individual’s coping skills (which are, in turn, influenced by personality and social
circumstances
Theories of Aging
PSYCHOSOCIOLOGIC THEORIES
•
Psychologic aging is characterized primarily by behavioral changes.
•
Sociologic changes refer to changes that relate to the environmental influences
that contribute to and affect aging people.
•
Each older person is an individual, and each life experience and each change
in a person's environment has an effect on that person.
Developmental Psychology (Paper I) Page 39 School of Distance Education Psychosocial Perspectives on Aging
•
Aging is defined here as the transformation of the human organism after the
age of physical maturity so that the probability of survival decreases & it is
accompanied by regular transformations in appearance, behavior, experience
& social roles.
•
Psychosocial aging can be described as a result of the disuse of previously
acquired skills, random wear & tear, a change in the ability to adapt due
environmental variables, loss of internal & external resources, genetic
influences over the life span.
•
Social scientists agree that genetics (heredity) is a major factor in determining
the length of human life, although environment plays an important role in
modifying the expected life span.
•
The bottom line of Psychosocial Theory: As people grow older, their
behavior changes, their social interactions change, and the activities in which
they engage change.
The four Psychosocial Theories we will discuss here are:
•
Disengagement theory
•
Activity theory
•
Life-course theories
•
Continuity theory
Disengagement Theory
•
Refers to an inevitable process in which many of the relationships between a
person and other members of society are severed & those remaining are
altered in quality.
•
Withdrawal may be initiated by the aging person or by society, and may be
partial or total.
•
It was observed that older people are less involved with life than they were as
younger adults.
Developmental Psychology (Paper I) Page 40 School of Distance Education •
As people age they experience greater distance from society & they develop
new types of relationships with society.
•
In America there is evidence that society forces withdrawal on older people
whether or not they want it.
•
Some suggest that this theory does not consider the large number of older
people who do not withdraw from society.
•
This theory is recognized as the 1st formal theory that attempted to explain the
process of growing older.
Activity Theory
•
Is another theory that describes the psychosocial aging process.
•
Activity theory emphasizes the importance of ongoing social activity.
•
This theory suggests that a person's self-concept is related to the roles held by
that person i.e. retiring may not be so harmful if the person actively maintains
other roles, such as familial roles, recreational roles, volunteer & community
roles.
•
To maintain a positive sense of self the person must substitute new roles for
those that are lost because of age. And studies show that the type of activity
does matter, just as it does with younger people.
The Activity Theory makes the following certain assumptions:
•
There is an abrupt beginning of old age.
•
The process of aging leaves people alone & cut-off.
•
People should be encouraged to remain active & develop own-age friends.
•
Standards & expectations of middle age should be projected to older age.
•
Aging persons should be encouraged to expand & be involved.
Life-Course Theories
•
One theory we are all very familiar with is Erikson's developmental stages,
which here approaches maturity as a process. Within each stage the person
Developmental Psychology (Paper I) Page 41 School of Distance Education faces a crisis or dilemma that the person must resolve to move forward to the
next stage, or not resolve which results in incomplete development.
Hanighurst stated that for older people to progress they must meet the following
tasks:
•
Adjust to declining health & physical strength.
•
Adjust to retirement & reduced income.
•
Adjust to the death of a spouse or family members.
•
Adjust to living arrangements different from what they are accustomed.
•
Adjust to pleasures of aging i.e. increased leisure & playing with
grandchildren.
A more recent framework used in conducting research following these assumptions:
•
Aging occurs from birth to death.
•
Aging involves biologic, psychologic & sociologic processes.
•
Experiences during aging are shaped by historical factors.
Continuity Theory
•
States that older adults try to preserve & maintain internal & external
structures by using strategies that maintain continuity. Meaning that older
people may seek to use familiar strategies in familiar areas of life.
•
In later life, adults tend to use continuity as an adaptive strategy to deal with
changes that occur during normal aging. Continuity theory has excellent
potential for explaining how people adapt to their own aging.
•
Changes come about as a result of the aging person's reflecting upon past
experience & setting goals for the future.
Biologic Theories
Biologic theories classify aging as genetic (heredity) & nongenetic (wear & tear).
•
Genetic theories are the most promising in relation to finding answers about
aging.
Developmental Psychology (Paper I) Page 42 School of Distance Education Genetic Theories
Error & Fidelity Theory
•
Ok, we all know an Error is a mistake and Fidelity refers to being faithful… so
knowing that we can discuss this theory. Also remember that this occurs over
a lifetime.
•
How does this theory apply to aging? Normally, we constantly or faithfully
produce cells throughout our bodies using our same correct DNA map (or
proteins) to do so time & time again. What this theory is saying is that over
time an error or mistake occurs in our DNA map (or proteins) and it begins to
produce cells that are not correct … it's like going from producing a high
quality product to producing a lesser quality product. This deterioration
results in aging and eventually over a lifetime, death.
Somatic Mutation Theory
•
This theory holds that Mutations are those inheritable changes that occur in
the cellular DNA. If there is extensive damage to DNA and it is not repaired,
then there will probably be an alteration in a genetic sequence. There has been
some suggestion related to background radiation of various types.
Glycation Theory
•
Suggests that glucose acts a mediator of aging.
•
Glycation is the nonenzymic reaction between glucose & tissue protein.
•
Studies conclude that glycation may have profound cumulative effect during a
person's life. The negative effects of this process on proteins may be a major
contributor to age changes.
•
The effects of this process may be similar to elevated glucose levels & shorter
life spans of diabetics.
Theories of cellular aging
Programmed Cellular Aging Theory
•
Suggests that aging may be a result of an impairment of the cell in translating
necessary RNAs as a result of increased turnoffs of DNA.
Developmental Psychology (Paper I) Page 43 School of Distance Education •
In other words, the transcription of these messages into functional proteins
may be restricted in older people.
•
Some segments of DNA become depleted with advancing age, or selected
cellular structures seem to change with age so that DNA transcription is
restricted.
Aging Pacemaker Theory
•
Suggests that one cell, or one type of tissue, interferes with cell proliferation,
thereby initiating the process of senescence throughout the body.
•
Some suggest the Thymus as the 'pacemaker' or 'biologic clock.'
Theories of the Organ System
Autoimmune Theory
•
As the body ages the immune system is less able to deal with foreign
organisms & increasingly make mistakes by identifying ones own tissues as
foreign (thus attacking them).
•
These altered abilities result in increased susceptibility to disease & to
abnormalities that result form autoimmune responses.
Neuroendocrine Control Theory
•
The neurologic & endocrine systems are major controllers of body activity.
•
During the human life span there is a 10% decrease in the weight of the brain
due to both loss of cells & fluids in the cerebrum.
•
It is suggested the age related changes in response to hormones may be the
result of changes in the receptors for hormones rather than changes in the
activity of the endocrine hormones themselves.
Nongenetic Theories
Effects-of-Temperature Theory
•
This theory suggests that humans might live longer if their body temperatures
were just 5 degrees lower than the usual 98.6 because there is a relationship
Developmental Psychology (Paper I) Page 44 School of Distance Education between high metabolism (which increases temperature) and shorter-lived
species.
•
It is also suggest that if humans could attain the lower temperature they
would live 20% longer.
Nutrient Deprivation Theory
•
Purposes that oxygen deprivation leads to senescence of deprived cells.
Lipofuscin Theory
•
Also referred to as the 'wear and tear' theory.
•
Suggests that as people age they produce age spots that are an accumulation
of 'biochemical debris' or waste products. It is believed that these waste
products accumulate until they interfere with cellular functioning
Developmental Psychology (Paper I) Page 45 
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