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Chapter Five
First Two Years:
Biosocial Development
Body Changes


Rapid changes
Consequences of neglect severe
Body Size

Most notable time for physical changes



in each of the first 12 months they grow an inch
birth weight usually doubles by 4 months and
triples by end of first year
head-sparing—biological protection of the brain
when malnutrition temporarily affects body
growth
Sleep

Newborns sleep about 17 hours per day





needed for rapid growth
REM sleep—rapid eye movement sleep—declines
quiet sleep increases at about 3 months
too immature to sleep through the night
Infant’s sleep patterns influenced by brain
waves and parents’ caregiving practices
Early Brain Development

Most critical biosocial aspect of growth



newborn’s skull disproportionately large
at birth, 25% of adult brain weight
by age 2, 75% of adult brain weight
Growth in the First Two Years
Connections in the Brain

Head measurement increases 35% in first
year

brain development: changes in the brain’s
communication system
Basic Brain Structures
•
Neurons—long thin nerve cells that
make up nervous system
-
•
•
created before birth
70% in cortex (brain’s outer layer)
Axons—nerve fibers that extend from
neurons that send impulses
Dendrites—nerve fibers extending
from neurons that receive impulses
Action Potential
http://faculty.washington.edu/chudler/ap.html
Action Potential
Areas of the Cortex
Basic Brain Structures, cont.
•
Neurons—long thin nerve cells that make
up nervous system
-
•
•
created before birth
70% in cortex (brain’s outer layer)
Axons—nerve fibers that extend from
neurons that send impulses
Dendrites—nerve fibers extending from
neurons that receive impulses
Basic Brain Structures, cont.
•
Each neuron has a single axon (nerve fiber)
that extends from it and meets the
dendrites of other neurons at intersections
called synapses
-
-
axons and dendrites don’t actually touch at synapses
electrical impulses trigger brain chemicals called
neurotransmitters, which carry information from
axon of sending neuron across synaptic gap to
dendrites of receiving neuron
synapses are critical communication links with the
brain
Connections in the Brain
Exuberance
•
•
•
At birth more than 100 million neurons
are present
Phenomenal growth is referred to as
transient exuberance—fivefold increase
in dendrites in first 2 years
As many as 15,000 connections may be
made per neuron
Experience Enhances the Brain

Specifics of brain structure and growth
depend partly on experience


exuberance is transient—transitional stage
between newborn brain’s immaturity and the
maturity of older child’s or adult’s brain
underused neurons are inactivated, or pruned
Experience Enhances the Brain, cont.

Reactions to Stress

experiencing stress may cause overproduction of
stress hormone
 developing brain can lose capacity to react
normally to stress
 normal neuron connections may have been pruned
for rapid response to repeated stress
Experience Enhances the Brain, cont.

William Greenough identified 2 experiencerelated parts of brain growth


experience-expectant brain functions
 require basic common experiences to develop
normally
experience-dependent brain functions
 depend on particular and variable experiences to
develop
Experience Enhances the Brain, cont.

Human brains are designed for expected
experiences


how the brain is structured and connected will
depend on those experiences
the brain expects certain experiences at certain
ages
 these experiences critical if connections are to
form; if connections not formed, plasticity may
allow new connections and pathways as
experiences continue
The Senses and Motor Skills

Sensorimotor Stage

cognition develops between senses and motor
skills
Sensation and Perception

All senses function at birth



sensation—the response of sensory system when
it detects stimulus
 begins with outer organ—nose, eyes, etc.
perception—mental procession of sensory
information when brain interprets sensation
 begins in the brain and requires experience
cognition—thinking about what was perceived
Listening
•
•
•
•
Begins prenatally and is acute at birth
Certain sounds trigger newborns’
reflexes
Newborns particularly attentive to human
voice
Newborns’ sensitive hearing combines
with brain to distinguish sounds
Looking
•
•
Vision the least mature sense at birth
Visual experience combined with visual
cortex maturation improves vision
-
•
with time scanning becomes more organized,
efficient, and centered
Binocular vision—ability to focus two eyes in
a coordinated manner to see single image
Tasting, Smelling, and Touching




taste—functions at birth; calmed by sugar,
sensitive to sour
touch—comforted by human touch; feel
pain
smell—can distinguish between odors and
have preferences
Early sensation is organized for


social interaction
comfort
Motor Skills

Most visible and dramatic body change of
infancy
Reflexes
•
Reflexes for survival are categorized
-
-
maintain oxygen supply (breathing)
maintain body temperature (crying, kicking)
manage feeding (rooting and sucking)
swallowing aids feeding
spitting up if too much has been swallowed
crying when stomach empty
Gross Motor Skills

Involve large muscles and body movements

crawling, creeping, walking
Fine Motor Skills

Small, finely tuned movements, especially
of hands and fingers, including





successful grabbing
fingering, pointing, and holding
grasping a moving object
transferring objects from hand to hand
adjusting reach
Age Norms (in Months) for Gross Motor Skills*
Variations and Ethnic
Differences

Age at which motor skills acquired varies
greatly because of




ethnicity
inherited factors—genetic differences
patterns of infant care
individual rate of physical maturation
Public Health Measures



Newborn Care
Immunizations
Nutrition
Immunization

Immunization—process that stimulates
body’s immune system to defend against
attack by a particular contagious disease



smallpox
polio
measles
Sudden Infant Death
Syndrome (SIDS)

Risk factors?




laying baby on stomach to sleep
secondhand smoke
low birthweight
formula feeding rather than breast feeding
Ethnicity and SIDS



Asian babies less likely to succumb
Babies of African descent more likely
Infantcare routines in different
cultures play a role
Nutrition

How Infants Are Fed
Breast Is Best
•
Breast Milk
-
•
Bottle Feeding: babies more likely to have
allergies
-
•
begins with colostrum, high-calorie nourishment
before milk “lets down”
easily digestible
has antibodies and antibacterial properties
better for baby’s health
better option if mother is HIV-positive or using
drugs
Feeding on Demand
Malnutrition

Severe Malnutrition



brain does not have enough nutrition to develop
normally
no body reserves to protect from disease
marasmus and kwashiorkor diseases are direct
result of malnutrition
Chapter Six
The First Two Years:
Cognitive Development
Sensorimotor Intelligence

Sensoritmotor intelligence—active
intelligence causing babies to think
while using senses and motor skills
Stages 1 and 2: Primary
Circular Reactions
•
•
•
The feedback loop involving the infants
own body; infant senses motion and tries
to make sense of it
Stage 1 = Reflexes
Stage 2 = First Acquired Adaptations
-
adaptations of reflexes, i.e., sucking—new
information taken in by senses and responded
to
Stages 1 and 2: Primary Circular Reactions,
cont.

Assimilation and Accommodation



assimilation—taking in new information by
incorporating it into previous knowledge
accommodation— intake of new data to readjust, refine, expand prior schema or actions
babies eagerly adapt their reflexes
and senses to whatever experiences they have
Stages 1 and 2: Primary Circular Reactions,
cont.

Sucking as a Stage-Two Adaptation


begin adapting at about one month
reflexive assimilation
Stages 3 and 4: Secondary
Circular Reactions
•
•
feedback loop involving people and objects
Stage 3 = Making Interesting Events Last
-
•
repetition
awareness
Stage 4 = New Adaptation and Anticipation
-
goal-directed behavior
object permanence
Stages 5 and 6: Tertiary
Circular Reactions

Feedback loop that involves active
experimentation and exploration
-

involves creativity, action, and ideas
Stage 5 = New Means Through Active
Experimentation

little scientist
Stages 5 and 6: Tertiary Circular Reactions,
cont.

Stage 6 = New Means Through Mental
Combinations


mental combinations—sequence of mental actions
tried out before actual performance
deferred imitation—perception of something
someone else does (modeling), then performing
action at a later time
Piaget and Modern Research



Habituation—process of getting used to an
object or event through repeated exposure
to it
fMRI—functional magnetic resonance
imaging measuring technique for brain
activity and neurological responses
First three years are prime time for
cognitive development
Information Processing

Information-processing theory—
perspective that compares human thinking
processes to computer analysis of data,
including sensory input, stored memories,
and output
Affordances


Affordances—opportunities for perception
and interaction offered by environment
How something is perceived and acted upon
depends on




past experiences
current developmental level
sensory awareness of opportunities
immediate needs and motivation
Sudden Drops

Visual cliff measures depth perception,
which is based not on maturity level but
affordance
-

depends on prior experience
Object Constancy
-
-
things remain what they are, despite changes
in perception or appearance
boundaries of three-dimensional objects
Movement and People



Dynamic perception—1 of the 2 principles
explaining infant perception; namely, that
from birth perception is primed to focus on
movement and change
2nd principle explaining infant perception
is that babies are fascinated by people
Infants most interested in emotional
affordances of their caregivers
Memory



Certain amount of experience and
maturation in order to process and
remember experiences
In first year infants have great difficulty
storing new memories
Older children often unable to describe
events that occurred when they were
younger
Memory, cont.

Very early memories possible if



situation similar to real life
motivation high
special measures aid retrieval by acting as
reminders
Reminders and Repetition

Reminder session—any perceptual
experience that helps a person recall an
idea or experience
A Little Older, A Little
More Memory



After 6 months infants capable of
retaining information for longer periods of
time with less reminding
Deferred imitation apparent after end of
first year
By middle of the 2nd year, children capable
of remembering and reenacting complex
sequences
A Little Older, A Little More Memory,
cont.

Memory is not just single entity; distinct
brain regions for particular aspects of
memory; humans have a memory for






words
images
actions
smells
experiences
“memorized” facts
Language: What Develops in
Two Years?

Most impressive intellectual
achievement of young child and also of
all humans
The Universal Sequence of
Language Development

Children around the world have the
same sequence of early language
development but

timing and depth of linguistic ability vary
First Noises and Gestures


Baby talk—high-pitched, simplified, and
repetitive ways adults talk to babies
Vocalization



crying
cooing
Babbling

deaf babies do it later and less frequently, but
are more advanced in
use of gestures
First Words

First word and sentences at age of 1
year
The Language Explosion and
Early Grammar



Naming explosion—sudden increase in
infant vocabulary, especially nouns,
beginning at 18 months
Holophrase—single word that expresses a
complete, meaningful thought
Grammar—all the methods that languages
use to communicate meaning
Theories of Language Learning


Even the very young use language well
Three schools of thought



infants are taught language
infants teach themselves
social impulses foster infant language
Theory 1: Infants are Taught

Skinner’s reinforcement theory: quantity
and quality of talking to child affects rate
of language development (learned)


parents are good instructors
baby talk characterized by
 high pitch
 simpler vocabulary
 shorter sentence length
 more questions and commands
 repetition
Theory 2: Infants Teach
Themselves

Chomsky and LAD (Language Acquisition
Device)—hypothesized neurological
(inborn) structure that prewires all
children for language, including basic
aspects of intonation, grammar, and
vocabulary


infants innately ready to use their minds to
understand and speak whatever language
offered to them
they are experience expectant
Theory Three: Social
Impulses Foster Language


Social-pragmatic—social reason for
language: to communicate
Infants seek to respond, which shows their
being social in nature— and thus mutually
dependent—by
-
-
vocalizing
babbling
gesturing
listening
pointing
A Hybrid Theory

Emergentist coalition—combination of
valid aspects of several theories
-
cortex contains many language centers
nature provides several paths to learning
language
Chapter Seven
The First Two Years:
Psychosocial Development
Theories About Early
Psychosocial Development

Importance of parents and their
contribution to emotional growth
Psychoanalytic Theory

Connects biosocial and
psychosocial development
Freud: Oral and Anal Stages


Oral Stage—1st stage, where infant
obtains pleasure through sucking and
biting
Anal Stage—2nd stage, where anus
becomes main source of gratification,
i.e., bowel movements and the control of
them
Erikson: Trust and Autonomy

1st Stage—Trust vs. Mistrust


basic needs need to be met with consistency,
continuity, and sameness
2nd Stage—Autonomy vs. Shame and
Doubt

basic desire to gain self-rule over their own
actions and bodies and to feel ashamed if it
doesn’t happen
Behaviorism

Infant’s emotions and personality are
molded as parents reinforce or punish
child’s spontaneous behavior


social learning adds to personality formation
social referencing strengthens learning by
observation
Cognitive Theory
•
•
Individual’s thoughts and values
determine perspective on the world
Working model—set of assumptions used
to organize perceptions and experiences
Epigenetic Theory


Each child is born with a genetic
predisposition to develop certain traits
that affect emotional development
Temperament—“constitutionally based
individual differences in emotion, motor,
and attentional reactivity and selfregulation.”



inhibited
uninhibited
epigenetic—though personality traits not learned,
environment affects their expression
Research on Temperament:
Nine Characteristics









activity level
rhythmicity
approach-withdrawal
adaptability
intensity of reaction
threshold of responsiveness
quality of mood
distractibility
attention span
Temperament and Caregiving

Inhibited vs. Uninhibited


responsive care and encouragement can help
inhibited children become less so
Match between parent and child

goodness of fit
Sociocultural Theory


Emphasizes the many ways social
context can have impact on infantcaregiver relationship
If social context changes, child can
change
Emotional Development in
Infancy

In the first 2 years of emotional
development, infants progress from
simple reactions to complex patterns
of social awareness
The First Year

Newborns’ first discernable emotions



distress
contentment
Later emotions (after first weeks)


anger
fear, expressed clearly by stranger wariness and
separation anxiety
The Second Year



Fear and anger typically decrease
Laughing, crying: more discriminating
New emotions appear




pride
shame
embarrassment
guilt
Self-Awareness

Foundation for emotional growth



realization of individual distinctions
At about 5 months begin developing a
sense of self apart from mother
15-18 months the “Me-self”

rouge experiment
Pride and Shame



Self-awareness becomes linked with
self-concept early on
Negative comments more likely to lead
to less pride or shame
Own pride can be more compelling than
parental approval
The Development of Social
Bonds

Social connections help us understand
human emotions
Synchrony





Synchrony—coordinated interaction;
attunement
Helps infants learn to express own
feelings
Imitation is pivotal
Becomes more elaborate and more
frequent with time
Learning through play


playful interactions by both partners
important for both to be responsive
Attachment

Enduring emotional connection


Proximity-seeking behaviors
Contact-maintaining behaviors
Secure and Insecure
Attachment


Bowlby and Ainsworth
Secure—relationship of trust and
confidence that provides comfort,
assurance, and secure base
Secure and Insecure Attachment, cont.

Insecure—relationship that is
unpredictable or unstable


avoidant: one person tries to avoid any connection
with another
resistant/ambivalent: anxiety and uncertainly keep
one person clinging to another
Measuring Attachment

Strange Situation—lab procedure to
measure attachment; observed are




exploration of the toys (caregiver present)
reaction to caregiver’s departure
reaction to caregiver’s return
disorganized behavior—neither secure nor
insecure attachment—marked by inconsistent
behavior of caregiver and infant toward each
other
Insecure Attachment as a
Warning Sign




Stressed mother (although not always
an indicator)
Mother too withdrawn
Inconsistent behavior of mother
(conflicting messages sent by her)
Insecure attachments repairable
Social Referencing

Looking to others for cues
Referencing Mom


Look to mother for comfort
Mother’s tone and expression can
become guide to how to react to
unfamiliar or ambiguous event
Referencing Dad




Fathers play more than mothers
Infants look to fathers for fun and
physical play
Physically active play with fathers may
contribute to development of social
skills and emotional expression
Physically active play with fathers
helps children master motor skills and
develop muscle control
Cultural Differences


Fathers, single mothers, grandparents,
and cultures with other family
structures still provide needed
referencing
Father’s involvement



can benefit later development of child
raise mother’s self-confidence
and two parents working together are better able
to meet infant’s needs than either alone
Infant Day Care



Almost all infants cared for by people
other than parents part of the time
Specifics vary from culture to culture
The older the child and the more
money the family has, the more likely
possibility of day care
Infant Day-Care




Family day care
Center care
Day care generally beneficial
High-quality programs include




adequate attention to each infant
encouragement of sensorimotor exploration and
language development
attention to health and safety
well-trained professional caregivers
Infant Day Care, cont.


Cognitive and biosocial development are
more advanced by day care than at home
Poor day care has detrimental effects
Conclusions in Theory and
Practice


No single theory stands out as best
interpretation of developments during
first 2 years
Do not know the extent to which positive
influence can compensate for negative
one
Conclusions in Theory and Practice, cont.


Parental attentiveness crucial to
synchrony, attachment, and social
referencing.
In dealing with children with problems,
need a practical rather than theoretical
approach that focuses on their specific
issues
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