Infant&Child_Notes_CHAPTER_3-4.docx

Infant&child___Development Chapter 3 notes

Parental history, age, healthy influence conception and health of pregnancy.

  • Many middle class women often wait before having a kid. However it becomes more difficult for women to have a kid the older they get.
    • Infertility has become more common in the US
  • Diagnosis and treatment have uncertain insurance coverage
  • Miscarriage is common and often has no identifiable causes.
    • Common, some estimates are that 50% of pregnancies are miscarries.
  • A single sperm penetrates the cell membrane of the ovum
  • Fertilization usually takes place in the fallopian tube
    • Tipically millions of sperm are included in ejaculation and only one will be fertilizing.
      • Placenta important for the development of the organism throught the umbellical cord.
    • Implants in the uterus are usually not problematic. But it might fall out the fallopian tube and attach outside the uterus or other organs in the lower body. Eggtopic pregnancy do not last and if the woman does not receive the right prenatal care she could bleed to death.
    • Implantation starts at around 6 days postfertilization and by 2 weeks, it is fully implanted
    • Placenta previa: occurs and diagnosed with ultrasound imaging and saves the baby and mother.
  • Early division
    • First division at 2 hours
    • By day 4= morula of 16 cells
    • Day 5= outer and inner cells diefferentiate
      • Outer cells will be placenta
      • Now blastocyst
    • Day 16= gastrulation
      • Extoderm develops into the sking and most to the nervous system-identical cells, each cells have the cells to generate an entire human being) mesoderm will become most of the tube work of the body (stomach), and endoderm (embyos that are not differentiate)

Developmental processes

Four developmental processes transform a zygote into an mebryo then into a fetus:

  • Mitosis:
    • Cell division resulting in 2 identical daughter cells
  • Cell migration:
    • Newly formed cells move away from point of origin
  • Cell differentiation:
    • Cells start to specialize in structure and functions (and establish specialized reservoirs)
  • Apoptosis:

After implantation, inner cells mass becomes the embryo

  • The neural tube is a U-shaped groove formed from the top layer of differentiated cells in the embryo which will become the spine of the baby
  • 1 in 1000 births is affected bu a clinically significan neural tube effect
    • Things like folic acid supplementation. In 1990 FDA implemented new foods with extra folic acid and there was a decrease of births with kids having problems.

Embryonic period

  • Over the course of this periods, we see large changes in body structures and baby become the size of a cherry. Large migration and differentiation of cells and genes switching on and off. Happens in Weeks 3 through 8.
  • Embryonic period shows differences in the formation of face. Especially in 5 and half weeks through 8. By 8 weeks the embryo is closer to human looking. The eyes are moving towards the front and hands are coming into shapes. Bones are not formed yet but the shape is there.

Fetal period: weeks 9 throught the end of pregnancy (38 weeks longgestation, 40 weeks past last period)

  • Dramatic changes over the course of this period of pregnancy. Detailed working systems and dramatic changes in size. The fat under the skin isn’t deposited until the end of the 7th month. Babies born after month 7 would be skinny and the color of the skin will be lighter and different.
  • By 22 weeks, some can survive with neonatal intensive care.
    • If they survive, they will have physical or neurological problems.
  • By 28 weeks many premature babies if they received adequate care will survive.
    • Some delayes in development but can be overcomed if they receive the right parental care.
    • Fully developed lungs
  • Cephalocaudal and proximpdistal development patterns

Fetal growth, experience and behavior

  • Neurogenesis essentially complete- 18 weeks
  • Spontaneous movement in embryonic stage, - 7weeks, as limbs develop increasing movement. In a second or later pregnancy, women will often report that around 12 weeks can feel fetal movement.
  • Tactile sensations, kinesthetic sensation, taste, smell, hearing, memory
    • Habituation to sound, learning specific patterns, music
    • DeCasper&fifer; DeCasper &Spence. Babies could learn to recognize specific patterns. During the last few weeks of pregnancy, mothers would read over and over a story like “Pete the cat” and the baby developed a memory of the mothers sound. Adter birth, the babies seemed to recognize the sounds
    • The baby knows hot to suck his thumb. Telling us about some of his motor control and kinesthetic

Mother’s health, medical care, and psychological states influence fetal development

    • Nutrition, weight, blood pressure
    • Prenatal care to identify and mitigate risks
    • Depression: low birth weight, attention
      • Predictive of depression after pregnancy. Untreated postpartum depression is painful for mothers and the mental health of the child.
    • Stress(cortisol passes placenta): blood flow to fetus & potential Hpc
    • From exercise and good for development of the baby
    • Chronic high stress can damage the blood flow of the fetus.

Three stages of labor

  • Stage one: the money begins producing more oxytocin, which helps prepare her body for labor and help stimulate contraction. Contraction cause the cervix to open/dilate, soften, shorten and thin. (Longer stage of labor; in low risk of pregnancy, normally done at home; transition state normal most painful.
  • Stage two: contractions propel the fetus down the birth canal. (delivery of the baby). When the woman has to help by pushing
  • Stage three: the placenta is expelled (delivery of the placenta). The placenta detaches from the uterus. Typically In within a few seconds after the delivery of the baby, the doctors cuts the umbilical cord.

Neonatal health

  • Doctors check for many things after the baby is born:
  • APGAR scores
    • A: Activity (muscle tone)
    • P: Pulse
    • G: Grimace (reflex irritability)
    • A: Appearance (skin color)
    • R: Respiration

A

P

G

A

R

  • Gestational age and preterm birth
  • Birth complications &weight
    • Prolonged labor, breech position, caesarean birth (for variety of reasons, 33%)
  • Birth weight: LBW & VLBW
    • If a baby is less than 5 and half pounds, its considered low birth weight, (3.5 and below is very low birth weight)
    • If a baby is born more than 9 pounds is considered high birth weight
  • Prematurity: birth before 37 weeks/36 weeks
    • Oxygen deprivation (anoxia)
      • Caused by umbilical cord is wrapped around the baby’s neck or other parts of the body
      • If the baby is born and it looks blue, a cold cap will be placed to lower the body temperature, or put in a coma and kept cold. Lowering the temperature will kepp the baby from destroying important neurons. (induced hypothermia)
    • Respiratory distress syndrome
      • Results from the membrane in the lungs nor functioning adequately.

Contextual influences: infant mortality and health

  • Economics of a country or community
  • Access to healthcare
  • Provider beliefs and biases about patients
  • Clearn water, clear air, adequate nutrition
    • The greater availability to kids vaccinations and clean water made the kids mortality drop from 1915 to 2020 (less than 10%)
  • To help low birth weight infants-physical contact; social interaction
    • Cuddle, caress, carry
    • Kangaroo care: naked baby against mother’s bare skin (will regulate body’s temperature

Babies brain development

    • Brain growth is very rapid. Double of its volume in 2 years; visual cortez, frontal cortex, motor and prefrontal areas
    • Cderebellum triples in size in the first year
  • Bidirectionality and brain specialization
    • Experience drives maturation, which enables more experience…
  • Plasticity
    • Brain responds to experience wirth specialization
    • Lesions to brain early and later may have very different effects.
  • Blood pressure
    • If the mother suffers with high blood pressure, the baby will most likely have health problems.

Infant sleep

  • For the first month, baby sleep 18 hrs a day. Not in long stretches of sleep. Sleep training is the idea to let a baby “cry it out”. Another approach is that when the baby cries you pick him up and then yo lay him down. If the baby cries again, the you just try and talk to him and try to calm him down before you pick him up. Giving him less to let him know he is okay.
    • Types of sleep (REM, non-REM)
    • Sleep-wake cycles: neantes sleep 18 hrs a day more in REM- may help organize visual cortex maintain vigilance
  • It is critical that babies sleep as it is critical that adults sleep.
  • Sudden Infant death Syndrome (SIDS)
  • Unexplained death of an infant up to 1 year; when the infant is left sleeping and dies during his sleep.
    • It’s the third leading cause of deaths in infants.
  • Triple risk moder: infant age, vulnerability-exposure to alcohol, tobacco, other drugs, genetic risk, exogenous stress-overheating, breathing obstruction, tobacco smoke.
  • Cultural influences on Sleep
    • Sleeping through the night-debates about sleep training
    • Where should babies sleep?
      • Co-sleeping with parents’ debate
      • AAP(American academy pedriatic) advices against co-sleeping
      • In one American ideal family, the organization should be with parents and baby sleeping in different room
      • AAP says that it would be better for the parents and baby sleep in the same room for at least 1 year

Nutrition and Breastfeeding

  • Breastfeeding benefits-easier bonding, lower obesity, higher cognitive ability
    • If the baby is not held while feeding, does not create good bonding
    • Breastfeeding is not a contraception, but it makes conception less likely to happen.
  • Breastfeeding may not be the best option for many women
  • Mothers who do not have support are less likely to breastfeed
  • Sensitive responsive care, informed nutrition are more important than breastfeeding.

Developmental cascades

  • A difficult (prematurity, LBW) start a difficult context (stressed family, low social support, low responsiveness) can lead to problems in social and cognitive development
  • A child that is born small and weak might miss some developmental miles stones for many months,
  • Even with a difficult stgart, social support for parents, parental sensitivity to needs of child, most premature, LBW infants experience early delays, but catch up on development.
    • Very early babies, in supported environment will catch up on development

Chapter 4

Perceptual and motor Development in infancy &toddler years

  • Perceptual development-with emphasis on vision
    • Perceptual narrowing & perceptual tuning
    • Intermodal perception, integration, categorization
      • The psychological processo of organizing and interpreting sensory information
      • Gestalt theory
      • James blooming buzzing confusion”
        • He didn’t believe that the young infants could critically think
      • Ecological theory of perception: argued that our perceptional systems evolves to detect environmental information.
        • Learning: gauging affordances for action (what actions are possible or not)
      • Perception-action feedback loop:
        • Eye, mouth, then head movement can be controlled in early infancy
        • Arms are initially waving in direction of interesting things
        • Reflexes generate much of earliest movement. Movement generates kinesthetic, tactile, visual input.
      • Perception of faces
        • Primary’s caretaker’s face is the first to be recognized. Up to 2 months, the babies prefer to look at their mothers instead. (8 week shift)
    • What is built-in, what develops?
  • Motor development & growth
    • Theories
    • Reflexes
    • Typical progression, cultural modification
  • Developmental cascades

Studies about infant perception

  • Preferential-looking tests
  • Habituation-recovery tests
  • Contingent reinforcement studies
    • Follow the learning principles of operant conditioning
    • Used by researchers to test whether infants increase a specific behavior if followed by certain stimuli
    • Contingent upon sucking rate DECasper &Spence’s study
    • Contingent kicking, rovee-Collier’s studies

Context of taste, Smell Perception

  • Taste preferences already present in neonates
  • Exposing infants to different tastes shapes infant taste perceptions
  • Early taste experiences set the stage for food choices and preferences later on.
  • Smell of mother, smell of mother’s breast milk, can calm preemie.

Infant’s vision

  • When a child is “looking” at you, he is also, actively looking, tracking objects and people, and recognizing familiar and loved faces.
  • Visual acuity
    • Acuity distantly approaches that of adults by age 8 months. Reaches adult acuity by 6 years
      • Increase in density of photoreceptors
      • Increase in lens accommodation
      • Increase in focusing
      • Experience expectant plasticity drives changes n retina, eye muscles, organization of visual cortex.
    • Some babies are born with cataract and it has to be removed very early in life so that the baby will have a normal vision.
    • How is it measured? Multiple methods.
      • Differential looking
    • Perceiving colors and experience expectant eye development
      • Development of the eye and visual cortex of the brain lead to improvements in infants’ color vision over the first months of life
        • 100% dependent on visual input to drive “cone packing”
    • Size and shape constancy are present at birth
      • Infants are first shown one object, then an identical in shape and pattern but different in size object, positioned so retinal image size is the same. Infants can distinguish between the objects.
    • Inant perception of figure and grown; object continuity
      • 2- and 4-month-old babies habituated to a moving rod, behind an ocluder, then saw a broken rod or a complete rod; dishabituated to the broken rod.
    • Eye movements: babies learn what mom
      • Babies learn what moms are talking about by following gaze; mom establish joint attention
      • Anticipatory eye movement. Important to figure out what “mom” is pointing at. It occurs before something occurs, In anticipation of object’s movement direction
      • Tracking is awkward and slow at birth, it will improve over time.
    • Perceiving depth, perceiving distance
      • Depth perception: the ability to perceive vertical distance from a top surface or space to a bottom one
      • Monocular, binocular and motion parallax cues
      • Binocular ability cues to perceive depth depends on visual experience, >2 moths worth, 10-16 weeks. Important for eating or breastfeeding.
      • Matter for matter survival, reducing impact of something, reflexes
      • Monocular cues can be used around 6 months.

The visual cliff to test depth perception

  • An apparatus with an apparent drop-off or cliff developed by Eleanor Gibson &Richard Walk
  • Infants (with crawling experience) crawled across the shallow side of the cliff but not the deep side, suggesting perception of depth.

Perceptual integration, intermodal perception, categorization

  • Very young infants are sensitive to temporal synchrony… things happening at the same time: like mouth movement& speech sounds, bouncing and the sound of it
  • Infant initially group items (form concepts) on the basis of perceptual similarity (shape) and gradually on the basis of function
    • Researchers proved this theory by giving kids plastic replicas of a plane and a bird and kids though that they were the same thing (like the place was a bird with big wings)
    • Habituation studies
    • Sequential touching studies

Full-term infants display a range of reflex behavior

  • Some have obvious survival value: rooting, sucking, swallowing, grasping, swimming, blinking reflexes
  • Some may have had survival value in the evolutionary past of our species (moro reflex)
  • Some may be precursors of later voluntary behaviors (like stepping-walking, tonic neck-reaching)
    • Swimming reflex has little survival value (the baby will move legs and arms to survive but it won’t last longer)
  • Others-Babinski reflex
  • Some of the reflexes don’t last forever
    • For example, rooting and sucking reflexes may last for 4-6 months.
    • Stepping reflex- typically disappear at 2 months
    • Thelen: babies get fatter faster than they get stronger
      • She took babies that stopped stepping and submerged in water (the baby showed stepping reflex)
      • She took babies that still had the reflex and pt them in water (the baby stopped showing the reflex)

Changes to the body-composition

  • During the first 2 years of life, children’s bodies change faster than at any other time after birth
  • Infants and toddlers grow in spurts, not in steady gains
    • The torso wades very much as babies put on fat on their body and their abdomen.
  • Baby fat peaks at about 9 months, helping infants maintain a constant body temperature
  • Muscle tissue increases very slowly during infancy and will not peak until adolescence.
  • Metabolism is at a life time high during the first 2 years.
  • Parts of the body grow at different rates, in two group patterns:
    • Cephalocaudal trend:
      • The head develops more rapidly than the lower part of the body
      • By age 2, the lower part of the body catches up
  • Growth norms: heigh and weight averages for children the same age
    • Some countries have food problems and many times kids do not live for long due to a lack of protein foods in their diets.
      • Marasmus: diet low in all essential nutrients
      • Kwashiorkor: unbalanced diet very low in protein, sufficient calories from carbohydrates, weaned children to age 5
  • Children of the same age differ in RATE of physical growth, reflecting genetics, nutrition, and parental care.
    • Heredity
    • Nutrition/malnutrition/undernutrition
    • Emotional nurturance and wellbeing/emotional deprivation
    • The role of genes is extremely strong.
  • Skeletal age, a measure of bone development, is the best estimate of a child’s physical maturity (physical age)

Sensitive periods in brain development

  • Extreme sensory deprivation early in life results In permanent brain damage and loss of functions
  • Examples of deprived early environments:
    • Babies born with cataracts in both eyes
    • Infants adopted after life in orphanages where they experienced severe neglect
      • Case studies like the Romanian orphans. Children in this country who because of stresses of one or both parents don’t get the care they need, they won’t develop a heavy, full, healthy and functional brain development
  • Appropriate early stimulation produces
    • Experience-expectant brain growth and plasticity, which depends on ordinary experiences
    • Experience-dependent brain growth and plasticity: additional growth as a result of specific learning experiences

Changes in sleep

  • Neonates often sleep 16-18 hours, but in 2-3 hours segments; bottle fed infants may sleep longer, earlier, by 3 months, many infants can sleep for 6-7 hours
  • Rapid brain growth means substantial change in sleep a d wakefulness patterns between birth and 2 years:
  • Also affected by cultural beliefs and practices and parents’ needs
  • At the end of the first year, infants approximate an adultlike sleep-wake schedule
  • Disturbed sleep and clinginess in toddlerhood come with awareness of the self as separate from others.
  • Restful sleep is vital for intants’ learning and memory
  • What is a good routine?
    • Reading, singing, rocking putting the sleepy but awake child down to sleep
    • Preschoolers: reading, signing, nighttime prayer if relevant, tucking the sleepy child in
  • What happens when babies wake up:
    • Kids wake up for the same reasons adults do: urination, bad dreams, or discomfort. Kids may wake up and cry, or wake up and get out of bed.

FFT

Failure to thrive is weight consistently <3rd -5th percentile for age and sex, progressive disease in weight to below the 3rd -5th percentile, or a decease in 2 major growth percentiles (height weight).

Motor development

  • Movement changes everything
  • Travel expands the mind- the social world of the infant is transformed by its ability to move where it wants to go. Even the language they are spoken to has changed by the parents.
  • Gesell-prehensile skills, motor development driven by maturation
  • Myrtle McGraw stressed the role of practice: jimmy &johnny
    • One twin received extensive motor practice (jumping, walking around, going up the stair)
    • The other one didn’t receive motor practice and the results were clear: one child was more athletic and stronger child compared to the other one.
  • Esther Thelen: dynamic systems
    • Argued that motor development proceeds by soft assembly. Emphasize interaction of many factors: neural mechanisms by also increases in strength, posture control, balance, perceptual skills, and motivation.
  • Reaching
    • For the first few months, infants are limited to preaching movement
    • At about 7 months, as infants gain the ability to sit independently, reaching becomes stable
    • Reaching shows signs of anticipation (grasping an object) and by 10 months of age, infant’s approach to an object is affected by what they intend to do with the
  • Locomotion
    • At around 8 months of age, infants become capable of self-locomotion for the first time as they (typically) begin to crawl
    • Infants begin walking independently at around 12 to 14 months of age, using a toddling gait
    • Withought diapers, gain is not toddling.

Cultural differences

Restriction of movement slows development

Promotion of sitting, strengthening of muscles, tendonds, ligaments ahastens development.