Human Development: Key Concepts in Physical, Perceptual, and Motor Development

Chapter 3: Tools for Exploring the World: Physical, Perceptual, and Motor Development

3.1 The Newborn

  • Reflexes: Unlearned responses triggered by specific stimuli; vital for survival.

    • Important reflexes include:
    • Rooting (search for food)
    • Sucking (feeding)
    • Eye blinks (protection)
    • Stepping as a precursor to walking.
    • Reflexes indicate health of the nervous system.

  • Assessing the Newborn:

    • Apgar Score: Quick assessment of the newborn's health based on:
    • Breathing
    • Heartbeat
    • Muscle tone
    • Reflexes
    • Skin color
    • Scored from 0 to 2, with total scores interpreted as:
    • 7+: good physical condition
    • 4-6: needs special attention
    • 3 or less: life-threatening.

  • Neonatal Behavioral Assessment Scale (NBAS):

    • Developed by Brazelton; assesses 28 behavioral and 18 reflex items across 4 systems:
    • Autonomic (body regulation)
    • Motor (activity level)
    • State (alertness)
    • Social (interpersonal interactions).

  • Newborn States:

    • Alert inactivity: calm, attentive, inspecting environment.
    • Waking activity: unfocused eyes, uncoordinated motions.
    • Crying: various types (e.g., basic, mad, pain cries).
    • Sleeping: averages 16-18 hours, follows a 4-hour cycle.

  • Sleeping Patterns:

    • Newborns have 4-hour sleep cycles: typically sleeping 3 hours, awake for 1.
    • REM sleep constitutes about 50% of newborn sleep.

  • Co-sleeping: Cultural practice outside North America; thought to enhance bonding. Potential dangers include increased SIDS risk if parents smoke, drink, or co-sleep unsafely.

  • Sudden Infant Death Syndrome (SIDS):

    • Sudden, unexplained death of an otherwise healthy infant.
    • Risk factors include:
    • Premature birth
    • Low birth weight
    • Parental smoking
    • Overheating during sleep
    • Certain ethnic backgrounds (African American, Native American).
    • Recommendations: Sleep babies on their backs.

  • Temperament:

    • Definition: consistent styles of behavior present from infancy; can affect later personality.
    • Rothbart’s three dimensions:
    • Surgency/extroversion (happiness, activity level)
    • Negative affect (fearfulness, frustration)
    • Effortful control (attention focus, impulse inhibition).
    • Temperament can be influenced by both hereditary and environmental factors.
3.2 Physical Development

  • Growth Patterns:

    • Rapid growth in the first year; doubles weight by 3 months, triples by 1 year.
    • Growth rates vary widely among children.

  • Nutrition:

    • Essential for supporting rapid growth; breastfeeding preferred for proper nourishment.
    • Bottle-feeding presents risks in developing nations due to contaminated water.

  • Malnutrition:

    • Affects 1 in 4 children under age 5; can lead to growth issues and brain damage. U.S. food insecurity affects around 11% of households.

  • Developing Nervous System:

    • Neurons are the building blocks; brain develops structures, synapses peak by 12 months, and pruning occurs over time.
    • Brain specialization principles:
    • Early specialization
    • Environmental stimulation importance
    • Experience-expectant vs. experience-dependent growth.
3.3 Moving and Grasping: Early Motor Skills

  • Locomotion Development:

    • Development of sitting, standing, and walking occurs over time, influenced by numerous skills.
    • Dynamic systems theory: Motor development involves organizing skills over time, adapting to specific tasks.

  • Coordination Skills: Learning to walk involves differentiation of skills, with unsupported walking beginning around 12-15 months.

  • Cultural influences: Training practices can accelerate or delay motor milestones.

  • Fine Motor Skills Development:

    • Involves reaching, grasping, and manipulating objects; develops progressively.
    • Handedness becomes evident in toddler and preschool years, influenced by culture.
3.4 Coming to Know the World: Perception

  • Senses:

    • Newborns excel at smell, taste, and touch, distinguishing between various stimuli.
    • Hearing: sensitive to sounds, prefer certain ranges, recognize names by 4 months.
    • Vision: development from 1 month to 1 year shows increased visual acuity, depth perception, and preference for faces.

  • Perceptual Integration: Infants integrate sensory information; intersensory redundancy enhances recognition and learning.

3.5 Becoming Self-Aware

  • Self-Concept:

    • Developing self-awareness measured through the mirror test.
    • Children start identifying themselves and reference personal pronouns.

  • Theory of Mind:

    • Understanding the relationship between desires and behavior evolves through different stages:
    • Recognizing desires by age 2.
    • Filing different beliefs and states of knowledge in subsequent years.
    • By age 4, children's understanding of behavior related to beliefs is well established.