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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
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 Potentialhttp://faculty.washington.edu/chudler/ap.html
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
• 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
Basic Brain Structures, cont.
• 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
Exuberance
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
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 experience-related 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
Experience Enhances the Brain, cont.
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
Sensation and Perception
• 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
Listening
• 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
Looking
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
Tasting, Smelling, and Touching
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
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
Fine Motor Skills
Age at which motor skills acquired varies greatly because of ethnicity inherited factors—genetic differences patterns of infant care individual rate of physical maturation
Variations and Ethnic Differences
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
Breast Is Best• Breast Milk
- begins with colostrum, high-calorie nourishment before milk “lets down”
- easily digestible- has antibodies and antibacterial properties- better for baby’s health
• Bottle Feeding: babies more likely to have allergies- better option if mother is HIV-positive or using
drugs• Feeding on Demand
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
Malnutrition
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
Assimilation and Accommodation assimilation—taking in new information by
incorporating it into previous knowledge accommodation— intake of new data to re-
adjust, 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 1 and 2: Primary Circular Reactions, cont.
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
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
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
Stages 5 and 6: Tertiary Circular Reactions, cont.
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 theory— perspective that compares human thinking processes to computer analysis of data, including sensory input, stored memories, and output
Information Processing
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
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
Very early memories possible if situation similar to real life motivation high special measures aid retrieval by acting as
reminders
Memory, cont.
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
Children around the world have the same sequence of early language development but timing and depth of linguistic ability vary
The Universal Sequence of Language Development
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
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
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 2: Infants Teach Themselves
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
Theory Three: Social Impulses Foster Language
A Hybrid Theory Emergentist coalition—combination of valid
aspects of several theories- cortex contains many language centers- nature provides several paths to learning language
Theories About Early Psychosocial Development
Importance of parents and their contribution to emotional growth
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
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
Erikson: Trust and Autonomy
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 self-regulation.” 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 infant-caregiver 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
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
Bowlby and Ainsworth Secure—relationship of trust and
confidence that provides comfort, assurance, and secure base
Secure and Insecure Attachment
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
Secure and Insecure Attachment, cont.
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
Referencing Mom Look to mother for comfort Mother’s tone and expression can
become guide to how to react to unfamiliar or ambiguous event
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
Referencing Dad
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
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
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