Download Child Development by DeHart

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Review for Test
Environmental Influences
Detection and Treatment of Disorders
Birth & its compicaltions
Cultural variations in Childbirth
Brain development in first year
Infant states
Reflexes
Habituation/dishabituation
Infant learning (including imitation)
Concept of preparedness
Motor skill development in first year
Sensory systems in the first year
Depth perception: monocular and binocular cues
Looming
Visual cliff experiments
Size and shape constancy
9/19 First test, bring Scantron 882 form and a #2 Pencil
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The nature of development
Preformationism, predeterminism, and empiricism
Heinz Werner: differentiation and hierarchic integration, spiral
pattern
Qualitative versus Quantitative change
Normative versus individual
Heredity and Environment (nature/nurture issue)
Piaget’s theory (mechanisms and major periods)
Information-Processing theories (sensory, short-term, and longterm memory)
Lev Vygosky and Sociocultural theories
Psychoanalytic theories (including Freud’s and Erkson’s stages)
Social Learning theory
Bowlby’s adaptational theory
Major issue: Gradual versus stage, Early versus current experience
Specificity versus generality
Methods of Developmental Psychology: Experiments, Natural
experiments
Copyright © 2004 The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
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Methods of Developmental Psychology: Experiments, Natural
experiments
Naturalistic observation, Longitudinal versus cross-sectional versus
cross-sequential (accelerated longitudinal design)
Challenges of doing research with children of different ages
Challenges of doing research with children from different cultures
Bidirectional effects
Effects of daycare
Contexts of Development
Marasmus, hospitalism, failure to thrive, institutionalization
Urie Bronfrenbrenner’s model: Biological environment, Immediate
environment
Social and economic environment, Cultural environment, and
interactions among the levels
Cell Division: mitosis and meiosis
Gene and Environment Interaction
Conception
Prenatal Development
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Stages from conception to birth
Mother’s Experience of Pregnancy
Problems in Prenatal Development
Ultrasound, amniocentesis, chorionic villus sampling, MRI, blood
tests
Genetic Defects
Environmental Influences (teratogens)
Detection and Treatment of Disorders
Birth & its complications
The Apgar Scale
Cultural variations in Childbirth
Concept of critical periods and their importance in prenatal
development
Brain development and timing of capabilities
Cycle of poverty
Brain development in first year
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Infant states
Reflexes
Habituation/dishabituation
Infant learning (including imitation)
Concept of preparedness
Motor skill development in first year
Sensory systems in the first year
Depth perception: monocular and binocular cues
Visual cliff experiments
Size and shape constancy
A neonate’s competencies have
5 important characteristics:
1.
2.
3.
4.
5.
They depend on prewired abilities built into the
nervous system at birth.
They often meet survival needs.
From the beginning, they involve organized
sequences of actions that serve some purpose.
They involve selective responses.
They allow infants to detect relationships
between actions and consequences.
Copyright © 2004 The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
The Mother’s Experience of Pregnancy
Trimesters:
Three-month periods that correspond to changes
in the mother’s experience of pregnancy.
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Fatigue, drowsiness, swelling, frequent urination, morning
sickness are common during the first trimester.
Intensity of symptoms varies from woman to woman.
Second trimester often the most enjoyable for the
mother.
Quickening: The first fetal movements, usually
felt by mother by end of the fourth month.
Third trimester can be trying, as the increase in fetal size
pressures her organs.
Copyright © 2004 The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Environmental Influences
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alcohol, tobacco, illicit drugs
medications
diseases
maternal stress
maternal malnutrition
maternal age
Teratogen:
Any substance in the environment that can cause physical
malformations during prenatal development.
Copyright © 2004 The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Detection & Treatment of Fetal Disorders
Ultrasound
A technique that produces a computer image of a
fetus by bouncing sound waves off it.
Amniocentesis
Withdrawal of amniotic fluid through a needle
inserted into the mother’s abdomen to check for
chromosomal abnormalities.
Chorionic villus A technique for analyzing fetus’s genetic makeup;
sampling
cells are suctioned from developing placenta
through small tube through vagina and cervix or
through abdominal wall.
Copyright © 2004 The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
The Stages of Labor
1.
2.
3.
Regular, strong contractions begin 15-20 min. apart;
become stronger, more frequent as labor progresses,
till cervix is fully opened (dilated). From an hour to
more than a day.
Normal, head-first deliveries begin 2nd stage with
crowning, when crown of infant’s head pushes
through cervix into vagina. 30 min. to 2 hrs.
Baby is delivered. Ends with delivery of afterbirth,
which includes placenta and other membranes.
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Apgar Scale
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Apgar scale – score (from zero to 10)
at one and five minutes after birth is
the sum of the ratings (0, 1, 2) for
heart rate, respiration, reflexes, muscle
tone, and skin color.
Scores below 5 indicate the need for
immediate medical attention.
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Low Birth Weight and Prematurity
Premature:
Born less than 35 weeks after conception.
Low birth weight:
Weighing less than 2500 grams at birth.
Very low birth weight:
Weighing less than 1500 grams at birth.
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Anoxia
A disruption in the baby’s oxygen supply
during or just after birth.
Can occur in two basic ways:
1.
Umbilical cord may become pinched
during delivery.
2.
In breech-birth, infant is delivered in
bottom- or feet-first position.
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Cultural Variation in Childbirth
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In Holland, most births take place at home
with a midwife.
Lay midwives deliver many babies in
developing countries.
The U.S. has changed somewhat over the past
30 years:
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Childbirth preparation classes, e.g. Lamaze method
Decreased anxiety about labor and delivery
Less reliance on painkillers
Increase in deliveries by cesarean section.
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Prenatal Development in Context
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Genes guide within environmental
contexts that include events and
developmental changes in the
past and present.
Genes are activated and
deactivated in response to
environmental signals.
The mother is embedded in
physical, social, and cultural
environment that can affect her
body and her developing child.
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Three themes
1.
2.
How heredity and environment work jointly
to guide development.
How infants’ initial skills and their
experiences provide seeds for development
of more complex and flexible skills by the end
of the first year.
3. Preadapted: Equipped at birth with built-in
capacities that make it possible to understand
the environment and form social
relationships.
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Copyright © 2004 The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Early Brain Development
Researchers use a combination of approaches to
study early brain development:
 Measure indirectly by charting head growth.
 Port-mortem examinations.
 Electroencephalography (EEG).
 Magnetic resonance imaging (MRI).
 Position emission tomography (PET).
 Estimate from animal experiments.
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Brain Growth
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Infant brain at birth is ¼ of its adult weight.
By one year, the brain has tripled in weight.
One measure of this growth is head
circumference, starting at 13.5 inches and
growing in spurts to its average adult size of
20.5 inches.
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Changes in Structure & Function
Developmental Timetable
• Spinal cord and brainstem (for basic reflexes &
survival functions) are fully functional at birth.
• The thalamus (sensory relay station), the
cerebellum (motor functions), the
hippocampus (memory formation), and the
cerebral cortex all undergo continued
development and reorganization.
• Cerebral cortex (higher cognitive functions) has
the longest period of continued development.
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Changes in Structure & Function
Developmental Processes
Early brain development involves 6 main processes:
• neurogenesis & neuron migration
• neuron elaboration & differentiation
• synaptogenesis
• glial cell formation & myelination
• increasing connections between brain regions
• pruning excess synapses & loss of plasticity
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Infant States
Sleep States
 There are two infant sleep states:
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Quiet sleep: Babies lie still, breathing slowly
and regularly.
Active sleep: They stir often, move arms and
legs, crinkle faces, breathe faster & more
irregularly, and sometimes show rapid eye
movements (REMs) behind closed eyelids.
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Distressed States
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Newborns usually spend less than 10%
of their time crying.
3 distinct crying patterns:
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2.
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hungry cries
upset cries
pain cries
Babies differ in how easily they can be
soothed by others or by themselves.
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Changes in States
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During the first few months, states
change often, but by five months they
are more predictable.
Babies vary in how frequently they
change states and in how smoothly they
make transitions.
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Reflexes in the Newborn
Reflex: An automatic, inborn
response to a particular stimulus.
sucking
When object brushes lips, rhythmic sucking occurs.
Babkin
When lying down, pressure on both palms causes head to turn,
mouth to open, eyes to close.
stepping
When held up, feet can make a stepping motion.
grasping
Pressure on palm causes fingers to curl and grasp.
tonic neck On back, tends to turn head to one side, extend arm and leg on that
side, flex limbs on other side (fencing position).
rooting
When cheek is stroked, head turns that way and mouth opens.
Moro
Startled, infant extends arms, brings them together, grasps fingers.
Babinski
When foot is stroked from heel to toes, toes fan out & foot twists.
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Infant Learning
Habituation: The decrease in attention
when the same stimulus is presented
repeatedly.
Orienting response: Response when
stimulus is first presented, involving
behavioral and physiological changes.
Dishabituation: Increased attention to a
new stimulus after habituation to a
previous stimulus.
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Associative Learning
Associative Learning
Learning certain stimuli or events tend to go together to
be associated with one another. 2 types:
Classical conditioning:
A learning process in which a new
stimulus comes to elicit an established
reflex response through association with
an old stimulus.
Instrumental (operant) conditioning:
Learning in which behaviors are
influenced by their consequences.
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Reinforcement: Consequences following a
behavior that increase the likelihood the
behavior will be repeated.
Contingencies: The relationships between
events and their consequences.
Shaping: Reinforcing gradually closer
approximations of a target behavior.
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Imitative Learning
Imitative learning: A way of learning new
behaviors by copying others’ behaviors.
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The Concept of Preparedness
Preparedness: The genetic predisposition to
learn certain behaviors.
Some see early social behaviors (e.g., smiling and cooing
when adults speak) fitting this concept.
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Copyright © 2004 The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Infant Motor Skills
Motor Skills and Physical Growth
There are major milestones in development
involving average ages, yet there is a great
deal of individual difference in the age at which
motor skills emerge.
Principles of Motor Skill Development
 differentiation
 cephalocaudal development
 proximodistal development
 joint role of maturation and experience
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Development of Specific Motor Skills
Controlled Eye Movements
Saccadic eye movements:
The rapid, jerky eye movements that occur when the gaze is
shifted to a new object.
Pursuit eye movements:
The smooth, continuous eye motions used to track a moving object.
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Development of Specific Motor Skills
Reaching and Grasping
Newborns
Prereaching: Early spontaneous arm movements, sometimes in
response to an object.
1-4 months Decline in prereaching.
@ 4 mos.
Intentional reaching emerges.
By 15 mos. Children commonly reach for things smoothly and accurately.
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Development of Specific Motor Skills
Walking
Depends on:
 ability to integrate systems including balance
 maturation of muscles & nervous system
 practice
Stereotypic leg movements:
Rhythmic, repetitive leg movements elicited automatically
when infant reaches a certain level of excitement.
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Sensing & Perceiving the World
Sensory Systems in the Newborn:
Vision
Issues include determining:
 How clearly can babies see?
 Can infants see colors?
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Sensing & Perceiving the World
Sensory Systems in the Newborn:
Hearing
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Fetuses respond to sound at 26-28 weeks.
For young infants to hear a noise, it must be 10-20
decibels louder than for adults.
It takes 12-13 years to equal adult hearing.
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Sensing & Perceiving the World
Sensory Systems in the Newborn:
Smell & Taste
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Infants’ senses of taste and smell are more fully
developed at birth than their vision and hearing.
Newborns seem to discriminate among sweet, sour, &
bitter.
Ability to sense saltiness develops gradually over 1st 4
months.
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Sensing & Perceiving the World
Sensory Systems in the Newborn:
Touch
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Touch is more fully developed at birth than other
senses.
This is adaptive because touch is involved in many
newborn reflexes.
Even premature newborns and older fetuses feel pain.
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Organization of Infant Sensory Behavior
Newborns use their sensory capacities in an
organized way:
 Babies visually scan environment rather than
simply staring straight ahead.
 Hearing a noise, they direct their gaze toward
it.
 They scan edges.
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Development of Perceptual Abilities
Perception: The process by which the brain
interprets information from the senses.
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Depth and Distance Perception
Kinesthetic depth cues: Information about depth &
distance is carried in the motion of objects.
Binocular depth cues: Cues resulting from the fact that
visual information reaches the brain from 2 eyes.
Pictorial depth cues: Cues used to depict depth & distance
in 2-dimensional pictures -- e.g., linear perspective.
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Size & Shape Constancy
Size constancy: Perceiving an object as constant
in size, even though its image on the retina
grows larger or smaller.
Shape constancy: Perceiving an object as
constant in shape, even though its image on
the retina changes shape when it is viewed
from different angles.
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Perception of Faces
Newborns do not look longer at faces than at
other equally complex figures.
By 3 months, infants prefer pictures of their
mothers to pictures of strangers.
By 5 months, infants can remember strangers’
faces.
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First Adaptations in Context
Newborns comes into the world prepared in
many ways for the developmental tasks they
face. They have:
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reflexes
a variety of sensory capacities
preadaptations to attend certain stimuli
preadaptations for social interaction
Environment, in turn, provides experiences that
help shape brain development, motor skills,
perceptual abilities, and learned behaviors.
Copyright © 2004 The McGraw-Hill Companies, Inc. Permission required for reproduction or display.