Chapter 7

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Chapter 7
Development Across the Lifespan
The Preschool Years:
Physical and Cognitive
Development
What’s going on to effect development
during the preschool years (ages 3 thru 6)?
• Preschool!
– The start of intellectual and social interaction
– Practice/preparation for child’s formal education
* TREMENDOUS growth and change during this
period!
– physical
• (weight, height, nutrition, health, physical
brain changes, motor skills)
– Cognitive
• (intellectual development, language)
Physical Growth…
The Growing Body
•
•
Preschool age children’s physical
abilities advance significantly
(compared to infancy stage)
Children grow steadily during the
preschool period
Physical
Development:
Gaining Height
& Weight
The figures show
the median point
for boys & girls at
each age (50% of
children above this
point, 50% below)
These averages mask individual
differences in height & weight
– By the age of 6, boys are taller and heavier, on
average, than girls.
– There are profound differences in height and
weight between children in economically
developed countries and those in developing
countries. WHY?
• Nutrition, healthcare
– Differences in height and weight also reflect
economic factors within the U.S.
• Children whose families are below the poverty level are
among the shortest of all preschool age children
Changes in body shape and structure
occur during the preschool years
A. Boys and girls become less chubby and
roundish and more slender (no more potbelly!).
B. Arms and legs lengthen.
C. Children grow stronger as muscle size
increases and bones become sturdier.
D. The sense organs continue to develop.
E. Body proportions are more similar to those of
adults (relationship between head and body
more adultlike).
Nutritional needs change during the
preschool years
(& effect development!).
•
•
The growth rate slows during this age,
thus preschoolers need less food to
maintain their growth.
Encouraging children to eat more than
they want to, may lead to increased
food intake.
(Nutrition during the preschool years, continued)
 Increased food intake may lead to OBESITY,
(defined as a body weight more than 20 % higher
than the average weight for a person of a given
age and height;
a. Obesity is more common among older
preschoolers than it was 20 years ago
b. Obesity is brought about by both biological
(genetics, responsiveness to sweets) and social
factors (parental encouragement).
It is important not to force children to eat too
much in the mistaken belief that they need more
food!
•
•
•
Children tend to be quite adept at
maintaining an appropriate intake of food.
The best strategy is to ensure a variety of
foods, low in fat and high in nutritional
content.
Children should be given the opportunity to
develop their own natural preferences for
foods (no one food is indispensable!)
Health & Illness
during the preschool years
•
•
•
The majority of children in the United
States are reasonably healthy.
For the average American child, the
common cold is the most frequent,
and most severe, illness.
The proportion of children immunized in
the U.S. has fallen during some
portions of the last two decades.
Recommended
immunization
schedule
(American
Assn. Of
Pediatrics).
In text…
Although physical illness is typically a minor
problem during the preschool years, more children
are being treated for emotional disorders
• The use of drugs such as
antidepressants and stimulants doubled
and tripled between 1991 and 1995
• Reason for increase is unclear
– Quick fix for behavioral problems &
normal developmental difficulties?
~Therapy is beginning to replace drugs as
the treatment of choice!
Numbers of Preschool Children Taking
Medication for Behavioral Problems
Injuries: The Dangers that Preschoolers Face
 The danger of injuries during the preschool years
is in part a result of children's high levels of
physical activity (they can get around on their
own now!).
– Poison, drowning in tub/pools, falls, burns
 Some children are more apt to take risks than
others, leading to more injury
– Boys have higher injury rates.
 Economic and ethnic differences exist in injury
rates.
–
–
Living in poverty environment = 2x higher risk
Cultural differences in supervision, gender roles
The Consequences of Lead Poisoning
High levels of
lead have
been linked
to higher
levels of
antisocial
behavior,
including
aggression &
delinquency
in school-age
children.
Another factor effecting development during
the preschool years: Brain Growth
 The brain grows at a faster rate than any
other part of the body!
• By age 5, children's brains weigh 90 % of
average adult brain weight.
• Brain growth is so rapid because of the
increase in the number of interconnections
among cells, and the increase in myelin (the
protective insulation that surrounds parts of
neurons).
The 2 halves of the brain begin to
become more differentiated and
specialized
•
The left hemisphere focuses on verbal
competence (speaking, thinking), and
considers information sequentially (focus
on parts).
• The right hemisphere concentrates on
nonverbal areas (spatial relations, music,
emotional expression), and considers
information more globally (focus on wholes).
(Brain lateralization continued)
•
•
The two hemispheres of the brain
act in tandem (work together)
despite specialization of
hemispheres (they are
interdependent, not independent)
This specialization is studied using
MRI’s and the lateralization pattern
is true for most people
Looking Into the
Brain…
These scans show
how different parts
of the brain are
activated during
certain tasks,
illustrating the
increasing
specialization of the
brain.
(Brain lateralization continued)
•
There are many individual differences
in the nature of lateralization, and in
relation to gender and culture.
– Males show greater lateralization of
language in the left hemisphere, whereas
for females, language is more evenly
divided between the two hemispheres.
(This may account for why female's
language development proceeds at a
more rapid rate during early childhood.)
(Brain lateralization continued)
 The differences in lateralization
between males and females may be
attributed to both genetic (corpus
callosum differences—larger in
women) and environmental factors
(girls typically receive greater verbal
encouragement).
(nature vs. nurture again!)
Links Between Brain Growth & Cognitive
Development…
• Neuroscientists are just beginning to
understand how brain development effects
cognitive development.
– It seems that there are periods of
childhood during which the brain
shows unusual growth spurts which
have been linked to advances in
cognitive ability.
• Spurts at age 1 ½ to 2 years of age:
linked to language increases
Brain Growth Spurt
Graph shows that brain activity increases drastically during 1
½-2 years of age when language dramatically increases
Motor Development in the Preschool Years
(ages 3—6)
•
Both gross and fine motor skills become
increasingly fine-tuned during this age.
– Preschoolers' level of activity is
extraordinarily high.
– According to research, the activity level
at age 3 is higher than at any other
point in the lifespan!
•
(Eaton & Yu, 1989; Poest et al. 1990)
(Motor Development in the Preschool Years
continued)
Girls and boys differ in certain aspects
of motor development.
• Boys, because of increased muscle
strength, tend to be somewhat
stronger.
• Girls tend to surpass boys in tasks of
dexterity or those involving the
coordination of limbs.
Some major gross motor skills in early
childhood
•
•
•
•
Hopping
Skipping
Running
Throwing
(see table ; emphasizes how gross motor skills
improve with time)
Fine Motor Skills are also
developing during this period
•
•
•
•
•
Using utensils to eat
Cutting things with scissors
Tying shoelaces
Drawing shapes
Puzzles
– Require much more practice than gross motor
skills!
A final component of motor
development: Handedness
•
•
Preference begins in infancy, but
more finalized in the preschool
years
Most preschool children show a
clear preference for the use of
one hand over another - the
development of HANDEDNESS.
(Handedness Continued)
– 90 % of preschoolers are righthanded
– more boys than girls are left-handed
(so there IS a gender difference)
• There is no scientific basis for myths
that suggest there is something wrong
with being left-handed.
Intellectual Development In the
Preschool Years
• How do the dramatic advances
in intellectual development that
begin during the preschool years
take place?
• We will consider several
different explanations…
Cognitive Changes that occur during the
preschool years: Intellectual Development
 Piaget's Stage of Preoperational Thinking
•
•
Piaget saw the preschool years as a time of
both stability and great change.
Preschoolers are in the PREOPERATIONAL
STAGE, from age 2 to 7
– characterized by symbolic thinking
– Mental reasoning emerges, use of concepts
– Less dependence on sensorimotor activity
for understanding the world
(Piaget's Stage of Preoperational Thinking
continued)
•
•
A key aspect of preoperational thought is
symbolic function ( the ability to use symbols,
words, or an object to represent something that
is not physically present).
– Using word duck as a symbol for an actual
duck
– Understanding that a toy duck represents an
actual duck
Symbolic function is directly related to
language acquisition.
The relationship between language
and thought
•
•
•
•
For Piaget, language and thinking are
interdependent (advances in language
during the preschool period = advances
in thinking)
Language allows preschoolers to
represent actions symbolically.
Language allows children to think
beyond the present to the future.
Language can be used to consider
several possibilities at the same time
• Do improved language abilities in
preschoolers lead to improvements in
thinking ability, or is it the reverse? A
controversial question in the field of
psychology!
• Addressing the question if thought
determines language or if language
determines thought, Piaget argued that
language grows out of cognitive
advances (more sophisticated thinking
patterns)
)
Another aspect of intellectual development during the
preoperational period (according to Piaget):
C ENTRATION - the process of concentrating on
one limited aspect of a stimulus and
ignoring other aspects (buttons)
• a major characteristic of preoperational
thought
•
the major limitation of this period because
it leads to inaccuracy of thought.
• The cause of the children’s mistake is
allowing the visual image to dominate their
thinking (appearance is everything!)
Centration: What You See is What You Think
Which row contains more buttons? Preschoolers usually
say that the bottom row has more because it looks longer.
(an example of conservation of number, which we will discuss)
Another aspect of intellectual development
during Piaget’s preoperational period…
Egocentrism, the inability to take the perspective of
others
• EGOCENTRIC THOUGHT, thinking that does not
take into account the viewpoint of others, takes
two forms:
1) Lack of awareness that others see things from
different physical perspectives.
2) Failure to realize that others may hold thoughts,
feelings, and points-of-view different from one's
own.
(EGOCENTRIC THOUGHT, continued)
•
•
Not intentional/inconsiderate—just lack
of understanding that everyone doesn’t
view things like them!
Egocentrism is at the root of many
preschool behaviors, for example,
talking to oneself and hiding games (if I
can’t see you, then you must not be able to
see me!).
More about intellectual development during
Piaget’s preoperational period
•
Preschoolers are unable to understand the
notion of TRANSFORMATION
( the process in which one state is changed
into another - because they ignore the
intermediate steps [ inability to
understand/fill in sequences of change] )
– Pencil; slugs crawling
The Falling Pencil & Transformation
Children in the preoperational period are not able to
understand the successive transformations that the
pencil follows. They cannot see the intermediary steps.
A number of advances in thought
occur in the preoperational stage.
1) INTUITIVE THOUGHT – (ages 4-7) the use of
primitive reasoning and avid acquisition of
knowledge about the world; simply put:
CURIOSITY
–
Leads children to think they know all the
answers for how the world operates, but no
logical basis yet
(advances in thought occur in the
preoperational stage, continued)
2) Children begin to understand
functionality - the concept that
actions, events and outcomes are
related to one another in fixed
patterns.
• Pushing pedals moves bike faster,
remote button changes channels on
TV
(advances in thought occur in the
preoperational stage, continued)
3) They begin to understand the concept of
identity - that certain things stay the same
regardless of changes in shape, size and
appearance
• Clay stretched out is the same amount of
clay rolled into a ball
 According to Piaget, understanding
identity necessary for children to develop
an understanding of conservation (which
is required for the child to transition to the
next stage in his theory)
Conservation: Learning that
Appearances are Deceiving
• Preschoolers do not understand
CONSERVATION - the
knowledge that quantity is
unrelated to the arrangement
and physical appearance of
objects
Types of Conservation Problems
• Number
– Rearranging elements
– The type of
conservation task
grasped the earliest!
• Substance
– Altering shape (clay,
water)
• Length
– Altering shape,
configuration
• Area
– Rearranging
figures
• Weight
– Altering
shape
• Volume
– Altering
shape
(water in
container)
Evaluating Piaget’s Approach to Cognitive
Development
•
Critics of Piaget's theory argue that he
seriously underestimated children's
capabilities.
–
–
–
They argue that cognition develops in a
continuous manner, not in stages.
They believe that training can improve
performance in conservation tasks.
They also argue that Piaget focused too much
on the deficiencies of young children's
thought.
Information-Processing Approaches to
Cognitive Development
•
•
View information processing as
changing during the preschool
years
2 domains of cognitive
development focused on :
1) Understanding of numbers
2) Memory development
(Information-Processing Approaches to
Cognitive Development, continued)
Understanding of numbers
 Information-processing theorists consider
preschoolers understanding of numbers as
sophisticated (although not totally firm)
• The average preschooler is able not only to
count, but to do so in a fairly systematic,
consistent manner (aware that one number
goes with each item, although may get
names wrong).
• By age 4, most can do simple addition and
subtraction and compare quantities.
(Information-Processing Approaches to
Cognitive Development, continued)
Memory development
•
•
AUTOBIOGRAPHICAL MEMORY,
memory of particular events from ones‘
own life, is not very accurate until after
three.
Preschoolers‘ autobiographical
memories fade, they may not be
accurate (depending when they are
assessed), and they are susceptible to
suggestions
(Memory Development in InformationProcessing Approaches, continued)
•
•
•
Preschoolers have difficulty describing
certain information and oversimplify
recollections which may have implications
for eye witness testimony.
Young children are susceptible to
suggestions from adults.
Questioning children right after the event
and outside the courtroom may produce
more accurate recollections.
The information processing approach to
understanding Cognitive Development
•
•
•
According to information-processing
approaches, cognitive development consists
of gradual improvements in the ways people
perceive, understand and remember.
Preschoolers begin to process information
with greater sophistication.
They have longer attention spans, attend to
more than one dimensions of an object and
can better monitor what they are attending
to.
Information processing provides a clear, logical, and
full account of cognitive development.
• Reliance on well-defined processes that can
be tested is one of this perspective's most
important features.
But, there are some criticisms…
• Information processing theorists pay little
attention to social and cultural factors.
• Information processing theorists pay too
much attention to detailed, individual
sequence of processes that they never paint
a whole, comprehensive picture of cognitive
development.
Vygotsky's View of Cognitive
Development: Taking Culture
into Account
 Culture and societies influence cognitive
development.
• Cognition proceeds because of social interactions
where partners jointly work to solve problems
(contrasts with Piaget’s emphasis on individual
figuring things out alone).
Cognition proceeds because of social interactions
where partners jointly work to solve problems…
• The partnership is determined by
cultural and societal factors
– Institutions that promote
development (play groups,
preschools)
– Emphasizing certain tasks (school,
work)
According to Vygotsky, children's
cognitive abilities increase when
information is provided within
their ZONE OF PROXIMAL
DEVELOPMENT (ZPD), the
level at which a child can almost,
but not fully, perform a task
independently, but can do so
with the assistance of someone
more competent..
Sample Zones of Proximal Development (ZPD) for Two
Children
The two children have similar performances on task
completed without assistance. With assistance, their
performance improves. The second child improves even
more, and therefore has a larger ZPD.
(Vygotsky’s ZONE OF PROXIMAL
DEVELOPMENT (ZPD), continued)
•
•
The assistance provided by other is called
SCAFFOLDING, the support for learning
and problem solving that encourages
independence and growth.
The aid that more accomplished individuals
provide to learners comes in the form of
cultural tools ( the actual physical items
such as pencils, paper, calculators, and
computers)
•
Vygotsky's view has become increasingly
influential in the last decade.
• It helps explain a growing body of research
attesting to the importance of social
interaction in promoting cognitive
development.
Criticisms…
• The zone of proximal development is not
precise and not easily testable.
• His theory is silent on how basic cognitive
functions such as attention and memory
develop.
The Growth of Language and Learning During
the Preschool Years: Language
Development
• During the preschool years, language skills
become more sophisticated
• Young children begin this period with
reasonably good linguistic (language)
capabilities, but gaps in both language
production (speech) and comprehension
(understanding)
• By the end of the preschool years, they can
hold their own with adults—language skills
develop
(Language Development, continued)
•
Between late twos and mid-threes,
sentence length increases.
•
SYNTAX (the ways words and
phrases are combined to make
sentences) doubles each month.
(Language Development, continued)
• By age three, children use plurals
and possessive forms of nouns
(boys/boy's), employ the past
tense (adding -ed), use articles
(the/a), and can ask and answer
complex questions ("Where did
you say my book is?").
Illustrates the
acquisition
of some of the rules of
Language and supports
Chomsky's claims of an
inborn ability to find
grammatical structure.
wugs
(Language Development, continued)
•
By six, the average child has a
vocabulary of 14,000 words.
• Preschoolers begin to acquire
the principles of GRAMMAR, the
system of rules that determine
how our thoughts can be
expressed .
Some more aspects of language
development during the preschool years…
 Preschoolers engage mostly in PRIVATE
SPEECH, speech by children that is
spoken and directed to themselves.
•
•
Vygotsky argues that private speech
facilitates children's thinking, helps them
control their behavior, solve problems and
reflect (private speech = cognitive
development)
20 to 60 % of what children say is private
speech
(language development during the preschool
years continued)
•
SOCIAL SPEECH (speech directed toward
another person and meant to be
understood by that person) increases.
–
–
–
–
Children speak to others rather than
babbling/speaking to self
Want others to listen
Become frustrated when unable to make
themselves understood
Adapt their speech to others
The language children hear at home
significantly influences their language
development.
•
Hart and Risley (1995) researched
the effects of poverty on language.
How?
Studied the language patterns used by
parents of different economic levels
as they interacted with their children
over a 2 year period
Hart and Risley (1995) found:
•
•
•
Economic level was a significant
factor in the amount of parental
interactions, types of language
children were exposed to, and kinds
of language used.
Poverty was also related to lower IQ
scores by age five
The longer children lived in poverty,
the more severe the consequences
Differential Language Exposure
Parents at different economic levels provide different language
experiences. Professional parents and working parents direct more
words toward their children than welfare parents? Why could this be
so?
Television: Learning From the Media
•
•
•
•
•
•
Average preschooler watches 20 to 30 hours of
TV a week!
Consequences of TV viewing are unclear.
Children do not fully understand the plots.
They may have difficulty separating fantasy
from reality.
Some information is well understood by young
viewers, i.e. facial expressions.
Yet, much of what is viewed is not
representative of events in the real world.
Television Time
 Television may be harnessed to facilitate
cognitive growth.
• Sesame Street is the most popular
educational program in U.S.
• Viewers had significantly larger
vocabularies.
• Lower income viewers were better
prepared for school, scored higher on tests
of cognitive ability, and spent more time
reading.
Television: learning from the media?
•
Critics of Sesame Street suggest
that viewers may be less receptive
to traditional modes of teaching.
• There are difficulties in assessing
the effects of educational viewing,
(e.g. the effects may be related to
parenting).
**BUT overall the results of watching
sesame street seem to be positive
+
Early Childhood Education
•
3/4 of children in U.S. are enrolled in
some kind of care outside the home.
•
•
•
Implicit or explicit teaching of skills
Major factor is working parents.
Evidence suggests that children can
benefit from early educational
activities.
–
“good” preschools = clear cognitive and
social benefits according to
developmental psychologists
There are a variety of early education
programs.
•
DAY CARE CENTERS are places that
typically provide care for children all
day, while their parents work.
–
–
Some are home-care.
Others are provided by organized
institutions
• Community centers, churches,
synagogues,etc.
• Often more stable/regulated.
(early education programs, continued)
•
PRESCHOOLS (“nursery schools”
provide care for several hours a
day, and are designed primarily to
enrich the child's development.
– More limited time (only 3-5 hours
per day)
– Mainly serve those in middle and
higher socioeconomic levels
• Montessori preschools
(early education programs, continued)
• SCHOOL DAY CARE is a child-
care facility provided by some
local school systems in the United
States
– About ½ the states in U.S. fund
prekindergarten programs
– Often targeted at disadvantaged
children
– Often high quality care
Care Outside the Home
About 75% of children in the U.S. are enrolled in some form of care outside the
home.
There are pros and cons of attending early
education programs
Advantages include
increases in :
• verbal fluency
• memory and
comprehension tasks
• self-confidence
• independence
• knowledge about the
social world
Disadvantages found
include children being
• less polite
• less compliant
• less respectful of
adults
• sometimes more
competitive and
aggressive.
The key factor in determining the effects of early
education programs is quality.
• Well-trained care providers.
• Overall size of the group and the child-care
provider ratio.
• Curriculum.
~ No one knows how many programs in the U.S.
can be considered high quality, but there are
far fewer than desired!
• The U.S. lags behind other industrialized
nations in the quality, affordability, and
availability of childcare.
Preschools Around the World
• In France & Belgium, access to preschool is a
legal right!
• In Sweden & Finland, preschool care is
provided automatically if needed
• Russia has an extensive childcare system
~This contrasts with the U.S., which has no
national policy on preschool education or the
general care of children!
The Purpose of Preschool
The main purpose of preschool is very different in
different cultures!

In the United States, preschools are
viewed as important in making children
independent and giving them a good start.
The best-known program designed to
promote future academic success is Head
Start
• Designed to serve the "whole child",
including physical health, self-confidence,
social responsibility, and social and
emotional development.
Is Head start successful?
• Success is controversial!
• Although graduates of Head Start
Tend to show immediate IQ gains,
these increases do not last.
• BUT participants are more ready for future
schooling and have better scholastic
adjustment
(spend less time in special education, less
likely to be held back)
Should we seek to improve cognitive skills
during the preschool years?
Developmental psychologist David Elkind
argues that U.S. society tends to push
children so rapidly that they begin to feel
stress and pressure at a young age.
• Better to provide an environment where
learning is encouraged, not pushed.
• Children require developmentally
appropriate educational practice, based on
both typical development and the unique
characteristics of a given child.
BUT…
• Pushing children to succeed may
only be overdone in middle and
higher socioeconomic groups, where
more resources are available
• For poorer children, the benefits of
formalized early learning programs
probably outweigh the drawbacks
(can compensate for lack of
economic resources and less
stimulating home environments)
DON’T fOrGet:
• Keep up with your reading!
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