Introduction to Psychology/Child and Adolescent Psychology/Infants and Toddlers

Physical Developments

• Prematurity
  • occurs before 37 weeks of gestation or about 3 weeks earlier than the normal due date
  • Low birth weight is weight less than 5 ½ pounds at birth (2 pounds lighter than average); indicates potential for health risks
  • Very low birth weight is weight less than 3 ½ pounds at birth (4 pounds lighter than average); indicates greater potential for health risks
  • Small for gestational age (SGA) is born below the tenth percentile of birth weight for gestational age; indicates serious health risks
  • Prevention includes childbirth classes, healthy lifestyles and especially good prenatal care, but sometimes there is nothing you can do
• Infant Mortality
  • Refers to deaths that occur before the age of 1 year
• Having a Healthy Baby
  • Prenatal care is important
• Growth of the Body and Brain
  • Physical Growth
    • Average birth weight is 7 ½ pounds, with males bout ½ pound heavier than females
    • Baby's weight doubles in first 5 months
    • About 20 inches at birth and half of adult height by age 2
  • Feeding and Nutrition (Breastfeeding)
    • Sterile, cheap, “specially formulated”
    • Colostrums are a thick, yellowish substance in breast milk containing important antibodies (only for the first few days of breastfeeding)
    • Breastfed babies are at less risk of SIDS, asthma, and other illnesses
    • Breastfeeding helps mom lose weight faster, and lowers risk of breast and ovarian cancer
    • Infectious diseases can be spread via breast milk, so some mothers can’t (iron enriched formula)
    • Exclusively for 6 months, slowly introduce iron-rich foods from 6-12 months, judgment call after
    • More likely if mom married, higher income, and supported to breastfeed, but only ¼ by 6 mnths
• Structure of the Brain and Nervous System
  • Spinal cord is the “information superhighway”
  • Brain stem controls automatic functions
  • Cerebellum is on the back of the brain and controls posture, body orientation, and complex muscle movements
  • Neurons are specialized cells that process information and allow communication in the nervous system (form by 7 weeks)
  • Cerebral cortex is the “gray matter” that forms the top portion of brain and is divided into the 4 lobes (10 wks)
• Forming the Brain and Nervous System
  • Neural tube at about 4 weeks, which later develops into central nervous system
  • Synaptogenesis is one form of neuron maturation in which dendrites and axons branch out to form an enormously large number of connections with neighboring neurons (by 23 weeks)
  • Most neural connections (synapses) form AFTER birth, as a result of maturation and experiences
  • Myelination is a form of neuron maturation in which the fatty insulation (myelin sheath) grows around the axons; occurs in different parts of the brain at different times
  • Programmed cell death is a process by which many neurons die during periods of migration and heavy Synaptogenesis (we lose half before even born!)
• Sensory Capabilities
  • Vision
    • Visual acuity is the ability to see fine detail
    • Infants prefer faces
    • Newborns vision is somewhere between 20/150 and 20/600, reaches 20/20 by bout 6 months
    • Normal color vision by 3 months
    • Prefer to look at green, yellow, or red over gray
    • Depth perception by just under two months, but afraid of cliff by time can crawl
    • Binocular disparity is the difference between the images projected on the two eyes
    • Pictorial cues are relative size and density of the pattern elements shown beneath the glass
  • Hearing
    • Hearing is functional before birth
    • Recognize own names by 5 months
  • Smell and Taste
    • Facial expressions show that newborn babies react to certain odors and tastes similar to adults
    • The fetal system is well enough developed sometime near the end of gestation to sense and store information about odors encountered before birth
• Motor Development
  • Reflexes
    • Reflexes are involuntary movements elicited by environmental stimuli
    • Important early indicators of nervous system function
    • Primitive reflexes disappear around 4 months; help the infant to find nourishment or might have served protective functions during earlier periods of evolution
    • Postural reflexes disappear by 12 months; help infants to keep their heads upright, maintain balance, and roll their heads in the direction of their body motion
    • Locomotor reflexes disappear by 4 months; mimic locomotor movements such as crawling, stepping, and swimming
  • Voluntary Movements
    • Gross motor development is the process of coordinating movements with the large muscles in the body (first step around 1 year)
    • Fine motor development is the process of coordinating intricate movements with smaller muscles
  • Influences on Motor Development
    • Maturation of the muscles and brain
  • Opportunities for practice
    • culture differences in early experience

Cognitive Developments

• Perceptual Development
  • research techniques:
    • Preferential-looking
      • technique used to test infant visual perception. If infants consistently look longer at some patterns than at others, researchers infer that the infants can see a difference between the patterns
      • Babies prefer moving stimuli, sharp color contrasts, symmetrical patterns, curved patterns, patterns with some complexity or detail, and patterns that resemble the human face
      • Babies are already equipped at birth with an innate schema, or mental framework, of the human face
    • Habituation-dishabituation
      • technique used to test infant perception. Infants are shown a stimulus repeatedly until they respond less (habituate) to it. Then a new stimulus is presented.
      • Habituation is the tendency of infants to reduce their response to stimuli that are presented repeatedly.
      • Dishabituation= is the recovery or increase in infant’s response when a familiar stimulus is replaced by one that is novel.
      • Intermodal Perception is the process of combining or integrating ifnormatino across sensory modalities.
    • “Impossible events” (Renee Baillargeon)
    • Most recent method of assessing infant cognition is via neuroscience (wave imaging)
• Explaining Cognitive Development: Piaget’s Constructivist View
  • Mental processes (thought, memory, solving problems, language)
    • Children’s thoughts gradually becomes more organized and complex (cognitive development)