PSYC121 - Introduction to Human Development Notes

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

  1. Nature/Nurture?

  2. Stages/Continuous?

  3. Critical/sensitive periods & importance of early experiences?

Jean Piaget

  • Pioneering developmental Psychologist (1896-1980)

Piaget’s four stages of cognitive development

  • 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

    • Perform reversible mental operations.

  • Stage 4 (12+): Formal operational

    • Adolescent/adult can apply logic abstractly & think hypothetically.

Lev Vygotsky (1896-1934)

  • Proposed the zone of proximal development (ZPD)

What is a zone of proximal development?

  • 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/Sensitive Periods in Human Development

  • Critical period: window when development MUST happen

  • Sensitive period: optimal window for development

Critical/Sensitive Periods Examples

  • The brain/nervous system can be particularly sensitive to certain environmental inputs at certain times.

    • Pre-natal brain & alcohol (teratogens)

    • Early childhood speech?

3 Main Types of Research Design in Human Development

  • 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

  • Example: The Dunedin Multidisciplinary Health and Development Study

    • 1972 – ongoing

    • https://dunedinstudy.otago.ac.nz/

    • 1037 newborn babies were assessed, then again at various ages (5, 7, 9, 11, 13, 15, 18, 21, 26, 32, 38, 45 years)

    • Ongoing…

Longitudinal Study Outcomes

  • Hundreds of journal articles published from this single longitudinal study.

    • Examples: Stress & biological aging; Social isolation & brain age; Oral health & quality of life

Longitudinal Studies Characteristics

  • 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

Sequential Studies

  • Minimise cohort effects by studying multiple cohorts longitudinally.

  • Combine the strengths of cross-sectional and longitudinal designs

  • Minimise cohort effects by including multiple cohorts and tracking them over time

  • Allow researchers to distinguish between age effects, cohort effects, and time of measurement effects

  • Wave 1 participants, Wave 2 participants, Wave 3 participants, Wave 4 participants

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

    • I can get smarter

    • Learning is my goal

    • Effort makes me stronger

    • I'd spend more time and work harder

    • Higher Achievement

    • 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 Preview

  • 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)