Developmental Psychology
Analyze prenatal development, attachment, cognition, moral development, adolescence, adulthood, aging, and nature-nurture interactions.
A lesson of AP Psychology, in Development, Personality, Motivation, and Emotion, about 10 minutes.
Developmental Psychology: Key Theories and Stages
By the end of this lesson, you will be able to compare Piaget, Vygotsky, Erikson, and Kohlberg's developmental frameworks and apply them to specific situations.
Piaget's Cognitive Development
Core ideas: children actively construct their understanding of the world. Cognitive development proceeds through distinct stages.
Key processes:
- Schema: mental framework for organizing information
- Assimilation: fitting new information into existing schemas
- Accommodation: changing schemas to fit new information
- Equilibration: the drive to balance assimilation and accommodation
The Four Stages:
| Stage | Age | Hallmark |
|---|---|---|
| Sensorimotor | 0–2 | Object permanence develops |
| Preoperational | 2–7 | Language; egocentrism; NO conservation |
| Concrete operational | 7–11 | Conservation; reversibility; concrete logic |
| Formal operational | 12+ | Abstract reasoning; hypothetical thinking |
Key terms:
- Object permanence: objects exist even when out of sight (appears ~8–9 months)
- Conservation: substance remains the same despite changes in shape (appears ~7 years)
- Egocentrism: inability to see the world from another's perspective (three mountains task)
- Theory of mind: understanding others have different mental states (~4 years; false belief tasks)
Vygotsky's Sociocultural Theory
Cognitive development is fundamentally social.
Zone of Proximal Development (ZPD): the gap between what a child can do alone and with guidance. Learning occurs in this zone.