Developmental Psychology Across the Lifespan
What to know
Development is studied via cross-sectional (different ages at once) and longitudinal (same people over time) designs. Piaget's stages: sensorimotor (0–2; object permanence), preoperational (2–7; egocentrism, lack of conservation), concrete operational (7–11; conservation, logical thought about concrete things), formal operational (11+; abstract reasoning). Vygotsky emphasized social learning and the zone of proximal development. Kohlberg proposed moral stages: preconventional (reward/punishment), conventional (social approval/rules), postconventional (abstract principles). Erikson described psychosocial stages across life, each with a crisis (e.g., trust vs. mistrust, identity vs. role confusion).
Attachment and parenting
Ainsworth identified secure, avoidant, and ambivalent attachment; Harlow's monkeys showed contact comfort matters. Baumrind's parenting styles: authoritative (high warmth and control, best outcomes), authoritarian, permissive, and uninvolved. Temperament has biological roots.
Adult development
Physical changes include menopause and aging; cognitive changes vary. Kübler-Ross's stages of dying (denial, anger, bargaining, depression, acceptance) are not rigidly sequential. Prenatal development: germinal, embryonic, fetal stages; teratogens harm development.
Traps
Piaget's preoperational child fails conservation and is egocentric; concrete operational children conserve. Don't confuse Kohlberg's levels. Authoritative ≠ authoritarian.
Rule of thumb
For Piaget, ask "can the child conserve and think abstractly?" No conservation = preoperational; conservation but no abstraction = concrete operational.