Infant Childcare Considerations
JayLee23The First Two Years: Body and Mind
chapter three
Invitation to the Life Span
Kathleen Stassen Berger | Fourth edition
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Growth in Infancy
Body size
Average weight
At birth: 7 pounds
At 24 months: 28 pounds
Average length
At birth: 20 inches
At 24 months: 34 inches
These numbers are norms or average measurements.
Averages and Individuals
Eat and Sleep. The rate of increasing weight in the first weeks of life makes it obvious why new babies need to be fed day and night.
Norms and percentiles are useful—most 1-month-old girls who weigh 10 pounds should be at least 25 pounds by age 2. But, although females weigh less than males on average, lifelong, it is obvious that individuals do not always follow the norms. Do you know a 200‑pound woman married to a 150‑pound man?
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Sleep
Sleep specifics vary because of biology and the social environment.
Newborns sleep about 15-17 hours a day, in one- to three-hour segments.
Newborns' sleep is primarily active sleep.
Newborns have a high proportion of REM (rapid eye movement) sleep.
Overall, 25 percent of children under age 3 have sleeping problems, according to parents surveyed in an internet study of more than 5,000 North Americans.
Newborns sleep about 15-17 hours a day, in one- to three-hour segments.
Newborns' sleep is primarily active sleep: often dozing, able to awaken if someone rouses them, but also able to go back to sleep quickly if they wake up, cry, and are comforted.
Quiet sleep: slow brain waves and slow breathing.
Newborns have a high proportion of REM (rapid eye movement) sleep, with flickering eyes and rapid brain waves.
Variation is particularly apparent in the early weeks. As reported by parents (who might exaggerate), 1 new baby in 20 sleeps 9 hours or fewer per day and 1 in 20 sleeps 19 hours or more.
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OPPOSING PERSPECTIVES
Where should babies sleep?
U.S. middle class infants sleep separated from parents; sleeping patterns are changing.
Decision to co-sleep or bed-share linked to culture, age of infant, mother’s education level, depressive state, and father involvement.
Asian, African, and Latin American infants co-sleep or bed-share.
Asian and African mothers worry more about separation; European and North American mothers worry more about lack of privacy.
Co-sleeping is a matter of custom, not merely income.
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Brain Development (part 1)
Prenatal and postnatal brain growth (measured by head circumference) is crucial for later cognition.
Head-sparing is a biological mechanism that protects the brain when malnutrition disrupts body growth.
The brain is the last part of the body to be damaged by malnutrition.
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Brain Development (part 2)
Exuberance and pruning
Specifics of brain structure and growth depend on genes and maturation, but even more on experience.
Early dendrite growth is called transient exuberance.
Unused dendrites whither (through pruning) to allow space between neurons in the brain, allowing more synapses and thus more complex thinking (sculpting)
Experience-expectant
Experience-dependent
Expansion and pruning of dendrites occur for every aspect of early experience.
Transient exuberance followed by pruning.
Early dendrite growth is called transient exuberance: exuberant because it is so rapid and transient because some of it is temporary.
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Brain Basics
Neuron
One of billions of nerve cells in the central nervous system (CNS).
Axon
Fiber that extends from a neuron and transmits electrochemical impulses from that neuron to the dendrites of other neurons.
Cortex
Outer layers of the brain where most thinking, feeling, and sensing occurs.
Prefrontal cortex
Area of the cortex at the very front of the brain that specializes in anticipation, planning, and impulse control.
Brain Development (part 3)
Dendrite
Fiber that extends from a neuron and receives electrochemical impulses transmitted from other neurons via their axons.
Synapses
Intersection between the axon of one neuron and the dendrites of other neurons.
Neurotransmitter
Brain chemical that carries information from the axon of a sending neuron to the dendrites of a receiving neuron.
Neurons and synapses proliferate (increase rapidly in number) before birth. This increase continues at a fast pace after birth, but soon an opposite phenomenon occurs: the elimination, or pruning, of unnecessary connections.
The last part of the brain to mature is the prefrontal cortex, the area for anticipation, planning, and impulse control.
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Connecting
The color staining on this photo makes it obvious that the two cell bodies of neurons (stained chartreuse) grow axons and dendrites to each other’s neurons.
This tangle is repeated thousands of times in every human brain.
Throughout life, those fragile dendrites will grow or disappear, as the person continues thinking.
The infant brain actually contains billions of new dendrites.
Every electrochemical message to or from the brain causes thousands of neurons to fire, each synapse to neighboring neurons.
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Face Lit Up; Brain, Too
This young boy enjoys the EEG of his brain activity.
Such research has found that babies respond to language long before they speak.
Experiences of all sorts connect neurons and grow dendrites.
Stress and the Brain
Infants need protection.
Shaken baby syndrome is a life-threatening injury that occurs when an infant is forcefully shaken back and forth. This motion ruptures blood vessels in the brain and breaks neural connections.
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Moving and Perceiving: The Senses (part 1)
Sensory development
Typically precedes intellectual and motor development.
Sensation
Response of a sensory system (eyes, ears, skin, tongue, nose) when it detects a stimulus
Perception
Mental processing of sensory information when the brain interprets a sensation
Moving and Perceiving: The Senses (part 2)
Perception follows sensation.
Infants' brains are especially attuned to their own repeated social experiences and perception occurs.
Infant brain and auditory capacity to hear sounds in the usual speech range
The parts of the cortex dedicated to the senses develop rapidly.
Moving and Perceiving: Hearing
Sense of hearing
Develops during the last trimester of pregnancy.
Most advanced of the newborn's senses
Speech perception by four months after birth
Hearing occurs in the temporal lobe of both hemispheres, the green and some of the pink parts of the brain.
Language comprehension is mostly in the left hemisphere, here shown in the brown/orange region that responds to known words, and Broca’s area, the pink bulb that produces speech.
Note that a person could hear but not understand or understand but not speak if Broca’s area is damaged.
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Moving and Perceiving: Seeing
Vision
Least mature sense at birth
Newborns focus between four and 30 inches away.
Experience and maturation of visual cortex improve shape recognition, visual scanning, and details.
Binocular vision between 2 and 4 months
Depth perception is usually present by 3 months, but understanding depth requires experience.
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Moving and Perceiving: Tasting and Smelling
Sense of smell and taste
Smell and taste function at birth and rapidly adapt to the social world.
Foods of culture may aid survival.
Adaptation occurs for both of these senses.
Learning About a Lime—As with every other normal infant, Jacqueline’s curiosity leads to taste and then to a slow reaction, from puzzlement to tongue-out disgust. Jacqueline’s responses demonstrate that the sense of taste is acute in infancy and that quick brain perceptions are still to come.
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Moving and Perceiving: Touch and Pain
Touch
Sense of touch is acute in infants.
Although all newborns respond to being securely held, soon they prefer specific touches.
Some touches may be experience-expectant for normal growth.
Pain and temperature
Pain and temperature are often connected to touch.
Some people assume that even the fetus can feel pain.
Others say that the sense of pain does not mature until months or years later.
Ability to be comforted by touch is one of the skills tested in the Brazelton Neonatal Behavioral Assessment Scale.
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Moving and Perceiving: Gross Motor Skills
Every basic motor skill develops over the first two years of life.
Course of development
Cephalocaudal (head-down) and proximodistal (center-out) direction
Sequence of emerging skills
Sitting unsupported
Standing, holding on
Crawling (creeping)
Standing, not holding on
Walking well
Walking backward
Running
Jumping up
See chart on p. 94 for additional information about age norms for gross motor skills.
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Moving and Perceiving: Fine Motor Skills
Fine motor skills
Physical abilities involving small body movements, especially of the hands and fingers, such as drawing and picking up a coin
Shaped by culture and opportunity
Sequence of emerging skills
Grasping rattle
Reaching to hold object
Thumb-and-finger grasping
Stacking two blocks
Imitating vertical line
See chart on p. 95 for additional information about age norms for fine motor skills.
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Infant Cognition: Piaget (part 1)
Sensorimotor intelligence
Piaget's term for the way infants think—by using their senses and motor skills—during the first period of cognitive development.
Sensorimotor intelligence
Piaget's term for the way infants think—by using their senses and motor skills—during the first period of cognitive development.
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Infant Cognition: Piaget (part 2)
Stage One
Reflexes
Stage Two
First acquired adaptations (stage of first habits)
Stage Three
Attempts to produce exciting experiences; making sights last
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Infant Cognition: Piaget (part 3)
Stage Four
New adaptation and anticipation (means to the end); more attuned to goals of others; increased social understanding
Object permanence
Stage Five
New means through active experimentation
Little scientists; trial and error
Stage Six
Mental combination use; intellectual experimentation via imagination
Deferred imitation
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Piaget Evaluated
Careful observation of child cognition at each stage; inspired future research
Underestimation of age at which various accomplishments occurred (e.g., object permanence, deferred imitation)
Sensory and motor ability emphasis limited understanding of early child cognition
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Infant Cognition (part 1)
Information-processing theory
Modeled on computer functioning
Involves step-by-step description of the mechanisms of thought.
Adds insight to understanding of cognition at every age.
Has overturned some of Piaget's conclusions—including the concept of object permanence.
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Infant Cognition (part 2)
Early memory
According to classic developmental theory, infants store no memories in their first year (infantile amnesia).
Developmentalists now agree that very young infants can remember; memory improves monthly.
Rovee-Collier’s mobile kicking research and others
Brain is an active organ even in infancy.
Infants remember not only specific events and objects but also patterns and general goals.
Language: The Universal Sequence (part 1)
Language and responding
Child-direct speech (motherese)
Babbling
Gestures
First words
Holophrase
Verbs and nouns
Naming explosion
Putting words together
Grammar
MLU
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Language: The Universal Sequence (part 2)
Listening and responding
Child-directed speech
High-pitched, simplified, and repetitive way adults speak to infants (Also called baby talk or motherese).
Babbling
Extended repetition of certain syllables, such as ba-ba-ba, that begins when babies are between 6 and 9 months old
Gradual imitation of accents, cadence, consonants, and gestures in the environment
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Language: The Universal Sequence (part 3)
First words
At about 1 year, babies speak a few words.
Spoken vocabulary increases gradually (about one or two new words a week).
Holophrase
Single word used to express a complete, meaningful thought
Infants differ in use of various parts of speech, depending on the language they are learning (e.g., more nouns and fewer verbs).
Cultural differences in language use
All new talkers say names and utter holophrases.
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Language: The Universal Sequence (part 4)
Verbs and nouns
Naming explosion
Once vocabulary reaches about 50 expressed words, it builds rapidly, at a rate of 50 to 100 words per month
21-month-olds say twice as many words as 18-month-olds.
Ratio of nouns to verbs vary from place to place.
This language spurt is called the naming explosion because many early words are names of people and things.
Theories about naming explosion
Some languages are more verb-friendly than others.
Social context provides interactions with specific objects and responses to people.
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Language: The Universal Sequence (part 5)
Putting words together
Grammar includes all the devices by which words communicate meaning.
Sequence, prefixes, suffixes, intonation, volume, verb forms, pronouns, negations, prepositions, and articles
Proficiency in grammar correlates with sentence length (MLU)
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Theory One: Infants Need to be Taught
B. F. Skinner (1957) noticed that spontaneous babbling is usually reinforced.
Parents are expert teachers, and other caregivers help them teach children to speak.
Frequent repetition of words is instructive, especially when the words are linked to the pleasures of daily life.
Well-taught infants become well-spoken children.
Theory Two: Social Interaction Approach
Social interaction fosters infant language.
Infants communicate because humans have evolved as social beings.
Each culture has practices that further social interaction, including talking.
Social impulses, not explicit teaching, lead infants to learn language.
Theory Two: Infant Self-Teaching Approach
Infants teach themselves.
Language learning is innate; adults need not teach it, nor is it a by-product of social interaction.
Chomsky
Language is too complex to be mastered through step-by-step conditioning.
Language acquisition device (LAD)
Language acquisition device (LAD): Term for a hypothesized mental structure that enables aspects of grammar, vocabulary, and intonation
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All True?
All perspectives offer insight into language acquisition.
Multiple attentional, social, and linguistic cues contribute to early language.
Different elements of the language apparatus may have evolved in different ways.
Current thinking
Children are not exclusively behaviorists, social learners, or innately driven, but all three.
Evolutionary theorists posit that language is crucial trait that make humans unique.
Surviving and Thriving
Better days ahead
United Nations estimates that more than 8 billion children were born between 1950 and 2015 and that almost 1 billion of them died before age 5.
Now, almost all newborns who survive the first month live to adulthood.
Infant survival and maternal education are the two main reasons the world’s fertility rate in 2010 was half the 1950 rate.
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Understanding Sudden Infant Death Syndrome (SIDS)
Until mid-1990s, tens of thousands of SIDS death in North America and England
Most deaths were sleeping position-related
Back to Sleep program cut SIDS rate dramatically
Other risks
Low birthweight
Exposure to cigarette smoke
Soft blankets or pillows
Bed-sharing
Abnormalities in brain stem, heart, mitochondria, or microbiome
SIDS—an infant’s unexpected, sudden death; when a seemingly healthy baby, usually between 2 and 6 months old, stops breathing and dies while asleep.
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Success and Survival
Immunization
Primes the body's immune system to resist a particular disease.
Contributes to reduced mortality and population growth.
Successes
Smallpox
Polio
Measles
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Success and Survival (part 1)
Immunizations are unsafe for:
Embryos/rubella
Newborns
People with compromised immune systems; herd immunity
Problems
Reactions
Potential side effects
Parental refusal; myths
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Success and Survival (part 2)
Adequate nutrition: breastfeeding
For every infant disease (including SIDS), breast-feeding reduces risk and malnutrition increases it, stunting growth of body and brain.
Breastfed babies are less likely to develop allergies, asthma, obesity, and heart disease.
As the infant gets older, the composition of breast milk adjusts to the baby's changing nutritional needs.
See Table 3.2 for details on the benefits of breast-feeding for baby and mother.
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Success and Survival (part 3)
Malnutrition
Protein-calorie malnutrition
Condition in which a person does not consume sufficient food of any kind that can result in several illnesses, severe weight loss, and even death
Stunting
Failure of children to grow to a normal height for their age due to severe and chronic malnutrition
Wasting
Tendency for children to be severely underweight for their age as a result of malnutrition
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Evidence Matters
Genes were thought to explain height differences among Asians and Scandinavians, until data on hunger and malnutrition proved otherwise. The result: starvation down and height up almost everywhere—especially in Asia. Despite increased world population, far fewer young children are stunted (255 million in 1970; 156 million in 2015). Evidence also identifies problems: Civil war, climate change, and limited access to contraception have increased stunting in East and Central Africa from 20 million to 28 million in the past 50 years.
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