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.