PYSCHOLOGY 9/15

Development: Core Ideas

  • Development is not only growth; it encompasses both growth and decline across the lifespan, with periods of maturation in some domains and decline in others. A key takeaway: development involves dynamic change, not a simple, ongoing increase.
  • The biopsychosocial lens integrates three interconnected levels:
    • Biology (genetics, biology, brain development)
    • Psychology (cognition, emotion, behavior)
    • Social (environment, culture, relationships)
      These three interact across the lifespan (e.g., adolescence involves biological changes, psychological processing, and social context).
  • Nature vs. nurture debate
    • Nature = genetics and biology; nurture = environment and experience.
    • The blank slate (nurture-only) view is discussed as a contrasting perspective to genetic influence.
    • In reality, development reflects a complex interplay between biology and environment; often described as roughly balanced (not purely one or the other).
    • Personal anecdote used to illustrate nature vs. nurture: a family background in special education and the author’s upbringing affecting development and interests.
  • Research framing in development
    • Emphasis on the interaction of biology, psychology, and social factors, especially during adolescence.
    • Theory-to-practice note: research often uses the biopsychosocial lens to examine how different processes shape development over time.

Key Concepts and Terminology

  • Biopsychosocial lens (Biology, Psychology, Social)
  • Schemas (Piaget): mental blueprints or frameworks for organizing knowledge
  • Assimilation (misrepresented as “simulation” in some slides): applying old schemas to new information
  • Accommodation: changing or expanding schemas in light of new information
  • Object permanence: understanding that objects continue to exist even when not perceived (crucial in sensorimotor development)
  • Egocentrism: difficulty seeing the world from others’ viewpoints (Piaget’s concept in early stages)
  • Conservation: understanding that quantity remains the same despite visible changes in shape or arrangement (e.g., liquid in different glasses)
  • Sensorimotor stage: birth to ~2 years; coordination of senses with motor actions; foundation for object permanence and early schema formation
  • Preoperational stage: ~2 to 7 years; symbolic thinking, language development, intuitive reasoning; egocentrism prominent
  • Concrete operational stage: ~7 to 11 years; logical thinking about concrete events; development of conservation and classification skills
  • Formal operational stage: ~11+ years; abstract reasoning, hypothetical thinking, planning; emergence of justice and liberty as abstract concepts
  • Neonatal/infant development concepts: reflexes (persistent vs temporary), motor development (sitting, crawling, walking), preferential looking (attention biases, potential autism markers), myelination, brain mass changes, schema development, and the impact of early experiences on later cognition
  • Fetal development periods (prenatal): germinal, embryonic, and fetal stages
  • Social determinants of health: how social and environmental factors (e.g., access to resources) shape health outcomes

Prenatal Development: Periods and Factors

  • Germinal period (weeks 0–2):
    • Fertilization occurs and a zygote forms; early development begins here.
    • Important for the foundation of subsequent development.
    • extGerminalperiod:extweeks0extto2ext{Germinal period}: ext{ weeks } 0 ext{ to } 2
  • Embryonic period (weeks 3–8):
    • Major organogenesis begins; the embryo starts forming limbs, organs, and a rudimentary brain.
    • Organs begin to develop, and the brain starts differentiating.
    • This period is highly sensitive to environmental influences (teratogens) that can affect development.
    • extEmbryonicperiod:extweeks3extto8ext{Embryonic period}: ext{ weeks } 3 ext{ to } 8
  • Fetal period (weeks 9–birth):
    • Growth and maturation of organs and systems; brain mass increases dramatically; brain circuitry becomes more complex.
    • This period is particularly sensitive to environmental exposures and postnatal factors.
    • Alcohol exposure can produce fetal alcohol spectrum disorders (FASD).
    • Other factors: infections, viruses, and maternal health conditions can influence development; timing and dose of exposure, fetal genetics, and postnatal environment all matter.
    • extFetalperiod:extweeks9exttobirthext{Fetal period}: ext{ weeks } 9 ext{ to birth}
  • Environmental influences during prenatal development:
    • Alcohol use can disrupt development (FASD).
    • Maternal infections or viruses can affect development.
    • Epidurals, C-section versus natural birth, and other childbirth factors are studied for their potential impact on the infant; timing and interaction with genetics are important.
  • Social determinants of health (prenatal and postnatal):
    • Access to resources (e.g., medications, healthcare, pharmacies) and broader environmental context influence health outcomes.
    • Example: living in a town with limited access to pharmacies and transportation can affect postnatal care and overall health.
  • Postnatal environment and health outcomes:
    • After birth environment shapes outcomes, including access to resources and care, which interacts with prenatal biology.

Early Development and Infancy

  • Infant reflexes: three categories described
    • Persistent reflexes: remain across the lifespan; some reflexes are present early and persist.
    • Temporary reflexes: disappear with development (e.g., later integration of certain reflexes as motor and cognitive systems mature).
    • Examples mentioned include reflexes that persist (and others like grasping) and how early experiences influence later behavior.
  • Motor development milestones:
    • Locomotion milestones (sitting up, crawling, walking) emerge as motor and perceptual systems coordinate.
    • Infants explore the world through movement and object interaction; they reach, grab, and explore objects.
  • Preferential looking:
    • A measure showing infants’ eye gaze biases; used to predict developmental trajectories, including potential autism markers (e.g., preference for a caregiver’s face).
  • Brain development in infancy:
    • Myelination: growth of the myelin sheath around axons speeds neural transmission; begins prenatally and continues to develop in infancy.
    • Dramatic increase in brain mass early on, followed