Human Development Notes
Introduction to Human Development
What is Human Development?
- The study of HOW people develop across the lifespan.
- Lifespan perspective: 8 broad stages, all influenced by both nature & nurture (genetics and environment).
- Pre-natal (conception-birth)
- Infancy/toddlerhood (0-2)
- Early childhood (2-6)
- Middle childhood (6-11)
- Adolescence (11-18)
- Early adulthood (18-40)
- Middle adulthood (40-65)
- Late adulthood (65+)
Aspects of Human Development
- Human development includes multiple aspects:
- Social
- Biological
- Emotional
- Physical
Three Big Issues in Human Development
- Nature/Nurture?
- Stages/Continuous?
- Critical/sensitive periods & importance of early experiences?
Piaget's Stages of Cognitive Development
- Jean Piaget (1896-1980): Pioneering developmental psychologist.
- Stage 1 (0-2): Sensorimotor
- Infants explore the world with their senses and behaviours; child is in the centre (egocentric).
- Stage 2 (2-7): Preoperational
- Use of symbols (like language); object permanence; can consider different perspectives.
- Stage 3 (7-11): Concrete operational
- The child can apply some logic, understand conservation and perform reversible mental operations.
- Stage 4 (12+): Formal operational
- Adolescent/adult can apply logic abstractly & think hypothetically.
Vygotsky's Zone of Proximal Development (ZPD)
- Lev Vygotsky (1896-1934) proposed the zone of proximal development (ZPD).
- We learn best just beyond the zone of our current capabilities with the help of a capable other.
- Learning is more a continuum than stages.
- Learning is social.
Stages and Continuous Development
- Some theorists integrate an understanding of the broad stages of Piaget's theory with an information-processing approach.
Critical and Sensitive Periods
- Critical period: window when development MUST happen.
- Sensitive period: optimal window for development.
- The brain/nervous system can be particularly sensitive to certain environmental inputs at certain times.
- Pre-natal brain & alcohol (teratogens).
- Early childhood speech?
Research Designs in Human Development
- Three main types of research design:
- Cross-sectional studies
- Longitudinal studies
- Sequential studies
Cross-Sectional Studies
- Snapshot of single time-point.
- Compare between different age groups.
- Relatively simple and fast.
- Cannot determine causality.
- Example: “What’s the difference between 100-year-olds and 60-year-olds?”
Longitudinal Studies
- Same individuals over time.
- Useful for assessing age-related changes in behaviour.
- Take a long time.
- High cost.
- Risk of attrition (participants dropping out).
- Susceptible to cohort effects.
- Example: The Dunedin Multidisciplinary Health and Development Study (1972 – ongoing).
- 1037 newborn babies were assessed, then again at various ages up to 45 years and ongoing.
- Hundreds of journal articles published from this single longitudinal study; for example, looking at stress & biological aging, social isolation & brain age, oral health & quality of life.
Sequential Studies
- Minimise cohort effects by studying multiple cohorts longitudinally.
- Combine the strengths of cross-sectional and longitudinal designs.
- Allow researchers to distinguish between age effects, cohort effects, and time of measurement effects.
What is Age?
- Chronological age
- Biological age
- Psychological age
- Social age
- Functional age
Ageing as a Mindset
- Ellen Langer’s counterclockwise study: Can your beliefs/environment make you biologically younger?
Growth vs. Fixed Mindset
- Carol Dweck: A Growth Mindset Drives Motivation and Achievement.
- Growth Mindset:
- I can get smarter.
- Learning is my goal.
- Effort makes me stronger.
- I'd spend more time and work harder.
- Higher Achievement.
- Reference: Blackwell, Trzesniewski & Dweck (2007) Child Development
The Brain
- The brain isn't born, it's built.
- Billions of neurons & ongoing neuroplasticity.
Why the Study of Human Development Matters
- Reveals how experiences, biology and environment shape us across life.
- Helps us understand ourselves and others (why people do what they do).
- Can save and improve lives.
- Better parents, teachers, educators, practitioners, carers, friends etc.
- Can guide policy and practices, shaping environments where people can thrive.
- Reminds us that change is always possible.
Human Development Recap
- 3 main types of study.
- Stages & continuous development.
- Nature & nurture interact.
- Entire lifespan from pre-natal to end of life.
- Some critical or at least sensitive stages.
- Next three lectures will cover in more depth physical, cognitive & social development.
Social Development
- Secure attachment leads to stronger relationships & resilience.
- How a baby responds to being left alone predicts how they’ll handle stress years later.
- Next lecture (from me) will cover this topic.