Dev psych lecture #4: stability vs change

Main question

Do we remain fundamentally the same across life, or do we change in fundamental ways as we age?

Cross-sectional design description (1), pros (2), cons (2)

• Collects data from different age groups at the same time (thus different individuals)

• Pros: Quick, cost-effective

• Cons: Individual differences, cohort effects (cohort/generation effects (due to historical environmental influences) can confound age effects)

Longitudinal design description (1), pros (1), cons (4)

• Follows the same individuals over time

• Pros: Controls for cohort effects → changes more clearly linked to aging

• Cons: Expensive, time-consuming, dropout (attrition), practice/performance effects (improvement from repeated testing)

Ecological Systems Theory (Bronfenbrenner) empahsis + layers w/ description (4)

• Emphasises bidirectional influence between individuals and their environment.

• Layers:

  1. Microsystem – direct relationships (family, friends).

  2. Mesosystem – interactions between microsystems (e.g., home–school link).

  3. Exosystem – indirect influences (parent’s workplace, media).

  4. Macrosystem – cultural values, laws, politics

Crystallised intelligence def + example

• Knowledge acquired through learning

• E.g. verbal knowledge

Fluid intelligence def + example

• Novel problem-solving ability + adaption to new situations

• E.g. matrix reasoning

Cognitive change w/ age: crystallised vs fluid intelligence

• Crystallised intelligence (facts, vocabulary, skills): generally stable or increases slightly with age

• Fluid intelligence (problem-solving, reasoning speed): declines with age

Erikson’s psychosocial theory components of each stage (3)

Components of each stage

• Crisis to resolve.

• Significant event.

• Virtue gained when resolved well

Erikson’s psychosocial theory stages + ages (8)

1. Infancy (0–1)

2. Toddlerhood (1–3)

3. Early Childhood (3–5)

4. Middle Childhood (6–12)

5. Adolescence (12–18)

6. Early Adulthood (20s–30s)

7. Middle Adulthood (40s–60s)

8. Late Adulthood (65+)

Infancy (3)

Crisis: trust vs mistrust

Important event: e.g. feeding

Virtue: hope

Toddlerhood (3)

Crisis: autonomy vs shame/doubt

Important event: e.g. toilet training

Virtue: will (feelings of independence)

Early childhood (3)

Crisis: initiative vs guilt

Important event: exploration

Virtue: purpose

Middle childhood (3)

Crisis: industry vs inferiority

Important event: school

Virtue: confidence

Adolescence (3)

Crisis: identity (strong sense of self) vs role confusion (weak sense of self)

Important event: social relationships

Virtue: fidelity - ability to balance sense of self + live by society’s expectations

Early adulthood

Crisis: intimacy vs isolation

Important event: relationships

Virtue: love - ability to form meaningful + secure relationships

Middle adulthood (3)

Crisis: generativity (legacy) vs stagnation (unproductive/uninvolved)

Important event: work + parenthood

Virtue: care (pride in accomplishments + developing sense of unity with life)

Correlates of success in middle adulthood (2)

• Increased cognitive function

• Decreased mental health issues

Late adulthood (3)

Crisis: integrity (satisfaction) vs despair (regret)

Important event: reflection on life

Virtue: wisdom (pride in accomplishments)

Criticisms + modern considerations regarding psychoanalytic approach (3)

• Stages may overlap; progression isn’t always linear or age-bound.

• Heavy emphasis on marriage in intimacy stage may not reflect contemporary life.

• Technology and social media may shift the timing and nature of identity formation (earlier exposure, online identities).

Evidence on personality stability (2)

• Example study: teacher ratings at age 14 vs observer ratings at age 77 showed low correlations, suggesting limited stability.

• Other research finds higher correlations, so results are mixed

Final conclusions (3)

• Lifespan development shows both stability + change depending on domain (e.g. personality traits vs cognitive abilities)

• Social, cultural + technological environments shape developmental trajectories

• Cross-sectional and longitudinal designs can yield different results