Chapter 8: Physical and Cognitive Development in Early ...
Transcript of Chapter 8: Physical and Cognitive Development in Early ...
Chapter 8:
Physical and Cognitive
Development in Early Childhood
McGraw-Hill © 2006 by The McGraw-Hill Companies, Inc. All rights reserved.
• Children’s body growth and change:
– Average growth is 2.5 inches and 5-7 pounds
a year during early childhood
(less for girls than for boys)
– Growth variation due to genetics, nutrition,
prenatal problems, experiences, and SES
– Factors that affect child’s growth:
• Growth hormone deficiency
• Mother smoked during pregnancy
– Brain growth in early childhood is not as
rapid as in infancy – changes occur in neurons
• Changes in child’s brain structure:
– Increase in number and size of nerve endings
– Increased myelination: better focus, coordination
– Increased dopamine concentration and most rapid
growth in frontal lobe during ages 3 to 6 years
– Rapid growth spurt periods and drastic tissue loss
of unneeded cells – brain is always “reorganizing”
• More research is needed to chart connections
between cognitive development, brain structure,
and information processing
Prefrontal cortex
Figure 8.1
The Prefrontal Cortex
This portion of the brain (bright blue) shows extensive development from 3 to 6 years of age and is believed to play important roles in attention and working memory
• Gross motor development in children:
– Simple run-and-jump movements enjoyed at age 3
– Child is more adventurous at age 4
– Child is self-assured taking hair-raising risks at age 5
• Fine motor skills in children:
– Picks up tiniest objects at age 3 but still a little clumsy
– Has trouble building high towers with blocks at age 4
– Has better eye, hand, and body coordination at age 5
– Right-handedness is dominant in all cultures and
appears to be genetically influenced
Figure 8.2
Development of Gross Motor Skills in Early Childhood
37 to 48 months 49 to 60 months 61 to 72 months
•Throws ball underhand
•Rides tricycle 10 ft
•Catches large ball
•With help does forward somersault
•Jumps 12 inches to floor
•Does 3 hops with 2 feet
•Steps on footprint pattern
•Catches bounced ball
•Bounces & catches ball
•Runs 10 ft and stops
•Pushes/pulls a wagon or doll buggy
•Kicks 10-inch ball toward target
•Carries 12 lb object
•Catches ball
•Bounces ball under control
•Does 4 hops on one foot
•Throws ball (44 ft – boys; 25 ft – girls)
•Carries a 16 lb object
•Kicks rolling ball
•Skips alternating feet
•Roller skates
•Skips rope
•Rolls ball to hit object
•Rides bike with training wheels
(Listed in approximate order of difficulty in each period)
Figure 8.3
Development of Fine Motor Skills in Early Childhood
37 to 48 months 49 to 60 months 61 to 72 months
•Approximates a circle in drawing
•Cuts paper
•Pastes using pointer finger
•Builds 3-block bridge
•Builds 8-block tower
•Draws 0 and +
•Dresses and undresses doll
•Pours from pitcher without spilling
•Strings and laces shoelaces
•Cuts following a line
•Strings 10 beads
•Copies figure X
•Opens and places clothespins (one-handed)
•Builds a 5-block bridge
•Pours from various containers
•Prints first name
•Folds paper in halves and quarters
•Traces around hand
•Draws rectangle, circle, square, and triangle
•Cuts interior piece from paper
•Uses crayons appropriately
•Makes clay object with 2 small parts
•Reproduces letters
•Copies 2 short words
(Listed in approximate order of difficulty in each period)
– About 95% of right-handed people primarily
process speech in left
hemisphere of brain
– Left-handers are
• More likely to have reading problems
• More common in musicians, mathematicians,
architects, and artists
• Nutrition in children:
– What is eaten affects skeletal growth, body shape,
and susceptibility to disease
– Average preschooler needs 1,700 calories per day
– Energy needs of individual children of same age,
sex, and size may vary
– Calories from fat should be limited
• Child obesity is
– A serious problem in the United States
– Linked to diabetes, low levels of fitness,
low self-esteem, and iron deficiency anemia
• Leading causes of death in U.S. children are
– Accidents
– Cancer
– Birth defects
– Heart disease
• Of concern for children’s safety today:
exposure to tobacco smoke and its link to
respiratory problems & vitamin C deficiency
Figure 8.4
Main Causes of Death in
Children 1–4 Years of Age
Influenza and pneumonia
Diseases of the heart
Assault (homicides)
12.5
0.8 1.2
2.5 2.8
3.6
Malignant neoplasms
Congenial malformations, deformations, & chromosomal abnormalities
Accidents (unintentional injuries) (Motor vehicle 4.3) (Other accidents 8.2)
Deaths per 100,000 children Figures based on 1999 U.S. survey
• Poor health of children from low SES is of concern
• About 11 million children are malnourished and at
higher risk for diseases and lead poisoning
• UNICEF’s annual reports of “under-5 mortality rate”
– Nutritional health and knowledge of mothers
– Levels of immunization, dehydration, income
– Availability of health services, clean water
– Overall safety of environment and sanitation
2
3
4
5
6
7
8
1
Sweden Sierra Leone
Haiti
China
Mexico
Russia
U.S.
Canada
Czech Republic
193 1 38 85 102 121 158 161 178
1990 - 2001
1960 - 1990
Under-5 mortality ranking in 2001
Rankings and Average Annual Percentage Reduction in Under-5 Mortality 1960–2001
Average annual reduction rate (%)
• A preschooler’s world is creative, free,
and fanciful
– Piaget’s preoperational stage: ages 2–7 years
• Child cannot think without acting
• Operations allow child to mentally rehearse
future physical acts, but thinking is still flawed
• First substage of preoperational thought:
• Symbolic functions include scribbled drawings
representing real objects
• Child at age 2–4, still very egocentric and animistic
Figure 8.7
The Symbolic Drawings of Young Children
“Pelican”
“Nose”
“More eyes”
“Eyes”
“Seal
”
(b)
(a)
(a) 3½-year-old’s
drawing of “a
pelican kissing a
seal” compared
with (b) 11-year-
old’s drawing
which is more
realistic and less
inventive
B C A B C A
Figure 8.8
Piaget’s Conservation Task
Child is asked if (A) and (C) have the same amount of liquid. The preoperational child says “no” and will point to (C) as having more liquid than (A).
Two identical beakers shown to child, and then experimenter pours liquid from (B) into (C)
• Second substage of preoperational thought
– Intuitive thought: child uses primitive reasoning but
is still centric in thought, lacks conservation abilities
• Preoperational child’s inability to mentally reverse
actions applies to numbers, length, volume, and area
• Some claim Piaget’s views were not completely correct
• Between ages 3-5, children exhaust adults with “why”
questions – the questions give clues to the child’s mental
development and reflect intellectual curiosity
Type of conservation
Number Matter Length
Initial
presentation
Two identical rows of objects shown to child
Two identical balls of clay shown to child
Two sticks are aligned in front of child
Manipulation
One row is spaced
Experimenter changes shape of one ball
Experimenter moves one stick to right
Preoperational
child’s answer to
“Are they still
the same?”
“No, the longer row has more”
“No, the longer one has more”
“No, the one on top is longer”
Figure 8.9
Some Dimensions of Conservation: Number, Matter, and Length
• Vygotsky’s theory:
– Zone of proximal development (ZPD):
• Lower limit can be achieved by child alone
• Upper limit can be achieved by child’s skills
with adult guidance and instruction
• Other limits can’t be achieved yet
– Scaffolding involves changing level of support
during a teaching session – close, direct instruction is
reduced
– Language is used for social communication, solving
tasks, and monitoring one’s own behavior
• Vygotsky claims that
– Language and thought develop independently of
each other and then merge
– Child uses language to communicate with others
before she/he can focus on inward thoughts
– Transition to use of internal speech occurs between
ages 3 and 7, and is followed by action without
speaking aloud
• Socially competent children use private speech more
• Piaget: self-talk is egocentric and reflects immaturity
• Research finds private speech is used more in difficult
tasks; users are more attentive and perform better
• Vygotsky’s recommended teaching strategies:
– Effectively assess child’s ZPD
– Use the child’s ZPD in teaching
– Used more-skilled peers as tutors
– Monitor child and encourage private speech
– Place instruction in meaningful context
– Transform the classroom with Vygotskian ideas
• Using Vygotsky’s ideas, children from collaborative
schools were more cooperative
Vygotsky
• Strong emphasis
• Social constructivist
• No general stages
• Zone of proximal
development, language,
dialogue, tools of the
culture
•It has a major role in
shaping thought
•It has a central role
•Teacher is facilitator
and guide, not director
Piaget
• Little emphasis
• Cognitive constructivist
• Strong emphasis on stages
• Schemata, assimilation,
accommodation, operations,
conservation, classification,
hypothetical-deductive
reasoning
•It has a minimal role
•It just defines existing skills
•Teacher is facilitator and
guide, not director
Figure 8.11
Comparison of
Vygotsky’s and
Piaget’s Theories
Sociocultural Context
Constructivism
Stages
Key processes
Role of language
View on education
Implications for teacher
• A child’s ability to pay attention changes significantly
during preschool years
• Memory:
– Short-term: one can retain information up to 30
seconds with no rehearsal – memory span increases
(in digits) with age but varies between individuals
– Speed and efficiency of memory process improves
with age and experience
– Young children can remember a great amount of
information when given the right cues and prompts
Figure 8.12
The Planfulness of Attention
J
(b) (a)
J
In 3 pairs of houses, the windows were different.
In 3 pairs of houses, all windows were identical.
By filming the reflection in children’s eyes, one could
determine what they looked at, how long they looked,
and the sequence of their eye movements. Children
under 6 were different from older children in this study.
Figure 8.13
Developmental Changes in Memory Span
In one study: memory span increased from 3 digits at age 2, to 5 digits at age 7, to 7 digits at age 12.
8
0
1
2
3
4
5
6
7
6 2 8 10 Adult 4 12
Age (years)
Digit Span
• The young child’s theory of mind:
– Age 2–3: children begin to understand three
mental states – perceptions, desires, emotions
– Age 4–5: children understand “false beliefs”
and that people can be mistaken
– Only beyond preschool years do children
have a deepening appreciation of the mind
– In middle and late childhood, children
understand beliefs are “interpretive”
Figure 8.15
Developmental Changes in False-Belief Performance
20 30 40 50 60 70 80 90 100 10
20
0
30
40
50
60
70
80
90
100
10
Age (months)
Percentage Correct
• As children develop through early childhood, they
– Grasp the rules of grammar at a rapid rate
– Make all sounds of their language
– Use most parts of speech correctly
– Overgeneralize the rules
– Manipulate syntactic structures
• By age 6, the average child has a speaking
vocabulary of 8,000 to 14,000 words
• At age 6, average child is learning 22 words per
day and understands past, present, and future
• Variations in early childhood education:
– Child-centered kindergarten: focus on whole child
– Montessori approach: teacher is facilitator, child
has freedom, with emphasis on peer interaction
– Reggio Emilia approach: mostly for special
children in Italy, learning by investigation and
exploration of topics
• Educational practices should be developmentally
appropriate, taking into consideration the uniqueness
of the child
• Project Head Start to help the disadvantaged:
– Federally funded, created in 1965
– Not all programs in the U.S. are equal
– Seeks to intervene where there is a
lack of enriched early childhood
educational experiences
• Issues in early childhood education:
– What should the curriculum be?
– Does preschool matter?
– When is a child ready for school?
30
0
10
40
50
60
70
20
Japan U.S.
Comparison of Japanese and U.S. Parents’
Views on the Purpose of Preschool
Percentage of parents who say that the purpose of preschool is to give children experience in being a member of a group
Figure 8.18