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7eCHAPTER FIVE – Outline
Reading Highlights:
changes in body size – pages 166-167
cephalocaudal and proximodistal trends – page 167
skeleton and skull growth – pages 167-168
teeth – page 168
brain development – pages 168-176
infant sleeping habits – page 176-177
heredity and growth – page 178
nutrition – pages 178-180
malnutrition – pages 180-182
nonorganic failure to thrive – page 182
learning capacities – pages 182-187
habituation and recovery – page 185-186
motor development – pages 187-193
perceptual development – page 193-203
Terms and Concepts:
cephalocaudal
brain plasticity
brain hemispheres
fontanels
experience expectant brain growth
gross motor
synapses
pincer grasp
lateralization
habituation
recovery
proximodistal
synaptic pruning
neurons
neurotransmitters
experience dependent brain growth
fine motor
myelination
contrast sensitivity
synaptic pruning
growth faltering
cerebral cortex
Main Ideas:
 Infants grow rapidly during the first two years. Development follows the
cephalocaudal and proximodistal trends. Growth occurs in spurts.
 The brain continues to grow rapidly after birth. New synapse formation
and myelination follow patterns that correspond to the development of new
motor, language and cognitive skills. The young brain is very plastic.
 Both heredity and environment affect growth.
 The amount of continuous sleep increases during the first year. Infant
sleep habits and patterns are strongly influenced by culture.
 Good nutrition is vital in infancy to support the rapid growth of body and
brain. Breast milk is the ideal infant food.
 Malnutrition can cause both body growth and brain development to be
permanently stunted.
 Infants need affection, security and stimulation in order to grow and thrive.
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Infants are active learners. They are attracted by novelty; this helps them
learn. When they become bored with a stimulus (habituation), they seek a
new stimulus to focus on (recovery). Imitation is also an important
learning process for infants.
Habituation/recovery helps us to know more about infant learning and
memory.
Appropriate stimulation is essential for brain development. Deprived
environments impair brain development as well as in all other domains.
On the other hand, environments that provide too much stimulation, or
stimulation of a type the infant is not yet ready for, also interfere with brain
development.
During the first two years of life children begin to master their own bodies.
They master gross motor skills before fine motor skills, and they combine
individual motor skills into more complex systems of motor action.
New motor skills result from the interaction of several factors: what the
body can do, what the central nervous system has “wired” for, what the
child wants to do (the infant’s goal), and what the environment allows or
encourages.
Infants’ motor milestones and motor sequences are influenced by cultural
values and practices.
Although vision is the least developed of the 5 senses at birth, it develops
rapidly, due to maturation of the eye and of the visual centers of the brain.
Motor activities like crawling help to improve visual perception of
dimension (3-D) and depth.
The young child is not physically and psychologically ready for toilet
training until the second birthday or even later.
Berk Chapter 5: Physical Development in Infancy and Toddlerhood
BODY GROWTH
By the end of the first year of life, an infant’s height increases by _____%.
By the end of the second year of life, an infant’s height increases by _____%.
Birth weight: doubles by age _______________________.
triples by age ________________________.
quadruples by age ____________________.
Infants grow in ____________________. They can grow as much as
half an inch in _________________________.
Infant body fat begins to increase during the last weeks of the prenatal period; this
continues through the first year of life, peaking at a round 9 months. The early rise in
body fat helps the infant to
__________________________________________________.
(In contrast to fat, muscle tissue grows slowly, and does not peak until
________________________________.)
There are normal differences in the development of children’s bodies.
3 factors that affect rate of growth are ____________________,
______________________, and __________________________.
The growth and development of the body follows patterns.
Cephalacaudal trend = ___________________________________________________.
Proximodistal trend = ___________________________________________________.
__________________ _________ is the best way to measure a child’s physical maturity.
Skull growth is especially rapid during the first two years because of large increases in
__________________ size.
Define fontanels:
_______________________________________________________________________.
The first tooth appears around age: _________________________.
By age 2 years, babies have about ________________ teeth.
BRAIN DEVELOPMENT
Neurons are _____________________________________________________________
_______________________________________________________________________.
The human brain has 100 to 200__________________ neurons, most of which are in
place by the end of __________________________________________________.
A very important part of brain development and functioning concerns how neurons
communicate with each other by developing a network of neural fibers.
Synapses are ____________________________________________________________.
Neurotransmitters are
______________________________________________________.
Neural fibers increase rapidly during infancy and toddlerhood and take up a lot of space
in the brain; to make more room, many surrounding _____________ die.
“Use it or lose it”:
Neurons that receive _________________________ from the environment continue to
form more and more complex networks; synapses and neural pathways that are not
stimulated (used) die off. This is called ________________ __________________.
Explain the benefit of this process:
_____________________________________________________________________
_____________________________________________________________________.
Another important process that occurs in the young brain is myelination.
What happens in myelination? _____________________________________________
________________________________________________________________________
_______________________________________________________________________.
The fatty myelin sheath is made up of glial cells. It is the rapid growth of glial cells in
the first two years that causes the young child’s brain to grow so much larger and heavier.
In recent years, much of our information about brain functions has come from new
imaging technology, such as _________________ or __________________. This
method of brain research is called neuro_________________________.
Describe the cerebral cortex of the brain and its function:
________________________________________________________________________
________________________________________________________________________
________________________________________________________________________
________________________________________________________________________
Name 3 functions that are controlled by regions of the cerebral cortex:
1.
2.
3.
The order in which cortical regions develop parallels the order in which ______________
________________________________________________________________________
The cerebral cortex has 2 halves or hemispheres. Each of the cerebral hemispheres has
specialized functions. This specialization is called ______________________________.
The left hemisphere controls the _____________________ side of the body and is
responsible for _________________________________.
The right hemisphere controls the __________________ side of the body, and is
responsible for ________________________________________________.
How do left-handed people differ from right-handed people in this regard?
________________________________________________________________________
The brains of young children are said to be very plastic. Define brain plasticity:
________________________________________________________________________
What are the advantages of plasticity?
________________________________________________________________________
Give an example of a sensitive period in brain development:
________________________________________________________________________
For an infant to have optimal brain growth, he/ she needs stimulation from rich and
varied experiences in a caring family environment, in appropriate amounts for his/ her
developmental level.
Too little stimulation results in
________________________________________________________________________
Too much stimulation may cause
________________________________________________________________________
Explain the difference between the 2 types of brain growth that result from stimulation:
Experience-expectant brain growth
________________________________________________________________________
________________________________________________________________________
(When does this occur?
)
Experience-dependent brain growth
________________________________________________________________________
________________________________________________________________________
(When does this occur?
)
INFLUENCES ON EARLY PHYSICAL GROWTH
The textbook says that both heredity and environment affect growth. Briefly explain
what this means.
________________________________________________________________________
________________________________________________________________________
________________________________________________________________________
Why is good nutrition especially important during the first 2 years of life?
________________________________________________________________________
List 3 advantages of breast-feeding over bottle-feeding:
1.
2.
3.
What dietary choices can parents of infants and toddlers make to help their children avoid
obesity later in life?
________________________________________________________________________
________________________________________________________________________
What fraction of the world’s children suffers from malnutrition before age 5? _________
How does extreme malnutrition affect brain development and learning potential?
_______________________________________________________________________
_______________________________________________________________________
_______________________________________________________________________
Define non-organic failure to thrive:
_______________________________________________________________________
_______________________________________________________________________
LEARNING CAPACITIES
Use your own words to explain the difference between classical conditioning and
operant conditioning. _____________________________________________________
________________________________________________________________________
________________________________________________________________________
Use your own words to explain habituation / recovery:
________________________________________________________________________
________________________________________________________________________
________________________________________________________________________
MOTOR DEVELOPMENT
Most babies follow the same __________________ of motor development, but there is
much individual difference in the ________________ of babies’ motor development.
An example of gross motor development is: _______________________________
An example of fine motor development is: ________________________________
As motor skills improve, children become a danger to themselves. Give 3 suggestions for
keeping infants and toddlers safe from harm:
1.
2.
3.
The text states that toilet training is best left until after the second birthday. Explain the
reasons for this:
________________________________________________________________________
________________________________________________________________________
________________________________________________________________________
During the first year of life, infants who do not yet speak are nevertheless doing a lot of
vital language learning. Can you identify the main thing they are doing while listening to
people talk?
________________________________________________________________________
________________________________________________________________________
Briefly summarize the important developments in babies’ visual perception that occur in
the first year:
________________________________________________________________________
________________________________________________________________________
________________________________________________________________________
Video Notes – Physical Growth and Motor Development, Birth to 2 ½ (Berk, Chapter 5)
Every child has her own unique rate and style of development.
There is no strong relationship between physical development and mental development.
PATTERNS OF DEVELOPMENT
 Even though each child’s development is unique, physical development in
childhood does tend to follow predictable patterns.
 At birth, head size equals one quarter of body height; by adulthood it is only one
tenth.
 The newborn’s arms and legs are short in relation to the body, but the limbs will
grow faster than the head or torso.
CHANGES IN MOTOR RESPONSE
 Newborns respond to a stimulus with undifferentiated gross movement.
(Example in the video: the infant’s foot is touched with an ice cube.) Their whole
bodies react to stimulus. Once a response starts, the infant has trouble stopping it,
even after the stimulus is removed. (Example in the video: the infant continues to
cry even after the ice cube is removed.)
 The degree of neurological development is one factor that determines how
quickly an infant can change their behavior.
 As the infant ages, his motor response to stimulus becomes more differentiated
and more specific. (Example in the video: when the child’s foot is touched with
an ice cube, he moves that foot away.)
Cephalocaudal Pattern – motor control of the body develops vertically, from the head
to the feet.
Proximodistal Pattern – motor control develops horizontally, from the mid-line (torso)
down the arms to the hands and fingers.
NORMS OF DEVELOPMENT
 Norms describe typical development. The predictable patterns of human growth
help us establish norms.
 Norms help us flag problems when a child’s development falls outside the wide
typical range.
 There are some differences in typical development between girls and boys. Infant
girls tend to have more fat and less muscle than boys, and they tend to be lighter
and shorter than boys. Boys tend to be more vigorous, but girls tend to develop
faster.
 Growth Averages: infant height increases 50% by the first birthday, and 75% by
the second birthday. Weight doubles by five months, triples by one year, and
quadruples by two years.
BRAIN DEVELOPMENT
 The internal organs do not grow at the same fast rate, except for the brain, which
grows very rapidly. At birth the infant brain averages 25% of adult brain weight;
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by 3 months it is 40%; by 6 months it is 50%; by 2 years it is 75% of adult
weight.
One factor in this increase in brain weight is the production of new synapses,
which are the connections that form between neurons (brain cells).
In the first few months of life, the number of synapses increases twenty times
over. Daily experiences and stimulation drive the production of new synapses.
Unused synapses wither away in a normal process called pruning.
Another factor in the increased size and weight gain of the young brain is the
process of myelination, by which the axons of the neurons are insulated with a
fatty substance made up of glial cells.
Myelination of the brain corresponds to the pattern of cephalocaudal and
proximodistal development.
The insulation of the axons with myelin results in speedier transmission of neural
impulses, and as a consequence, the infant’s abilities expand.
ENVIRONMENTAL FACTORS IN DEVELOPMENT
 Adequate nutrition is essential to healthy development. Without proper nutrition,
the bones and muscles do not grow to their optimal size. Serious malnutrition
prevents the head from reaching maximum capacity, and may limit brain size.
Malnutrition interferes with the process of myelination. Poor nutrition also
reduces resistance to disease, creating a destructive downward spiral for the child.
 Emotional deprivation – when caregivers are indifferent or hostile to the child –
results in failure to thrive. Emotionally deprived infants have poor muscle tone.
Their bones do not mature normally. The development of their motor abilities
may be retarded. Children with non-organic failure to thrive may be slow to
walk and talk.
 Practice in some motor skills may speed up their acquisition, but the gains seem
to be only temporary.
 Typically developing infants do need visual, tactile, motor, and language
stimulation, but they do not need special equipment, exercises, classes or toys!
The average healthy loving family home provides the right amount of stimulation
for a developing infant or toddler!
SEQUENCES OF DEVELOPMENT
(See textbooks)
Toilet training (2 ½ to 3 ½ years) requires physiological / neurological readiness on the
part of the child, and patience and observation of the signs of readiness on the part of the
adult.
Practice Quiz 5
1. During pregnancy and infancy the head develops more rapidly than the lower part of
the body. This trend is called:
a. proximodistal
b. cephalocaudal
c. anterior dorsal
d. skeletal-motor
2. At birth, the skeletal age of ________ tends to be ahead of _______by about
_____weeks.
a. girls, boys, 1 to 2
b. boys, girls, 1 to 2
c. girls, boys, 4 to 6
d. boys, girls, 4 to 6
3. ______________ is a major reason for the great increase in brain size in the first two
years.
a. lateralization
b. synaptic pruning
c. development of new neurons
d. myelination
4. Which two are examples of experience-expectant brain growth in infancy and
toddlerhood?
a. learning to walk and to swim
b. learning to talk and to finger-feed
c. learning to talk and to sing abc’s
d. learning to answer a cell phone and turn on a tv
5. When parents consider the motor development of their infant, they should
a. be worried if their child does not hit the milestones exactly when the charts list
them
b. pay careful attention to when other peoples’ children start to sit up, crawl, walk,
etc., and worry if their child doesn’t keep up
c. remember that early motor development indicates advanced development in other
areas like cognitive and language development
d. remember that there are wide individual differences in normal motor development
6. Infants gain control of their __________ before their ___________.
a. torso, head
b. torso, arms
c. legs, torso
d. feet, legs
7. Which of the following reasons is the least dependable one for choosing breast
feeding?
a. the baby will obtain some anti-bodies through the mother’s milk
b. breast milk provides complete nutrition
c. breast feeding may help to prevent pregnancy
d. breast feeding won’t cause dental problems
8. Which of the following would be least important for a baby’s brain development?
a. loving interaction with caregivers
b. caregiver who talks to the baby
c. safe everyday objects to grab and explore
d. Mozart music and computers
9. As a baby become more mobile, the caregiver should
a. make it very clear to the baby what the safety rules are
b. rely on playpen to keep the baby out of dangerous situations
c. start firm discipline to keep the baby from touching harmful or breakable objects
d. “baby proof” the environment and supervise the child carefully
10. A baby has become bored with a particular rattle, and looks away when his mom
shakes it in front of him. This is an example of
a. recovery
b. habituation
c. operant conditioning
d. extinction