Developmental Psychology
The Developmental domain covers change across the lifespan: prenatal development, cognitive stage theories, language acquisition, attachment and parenting, moral reasoning, and aging. Items usually present a child's behavior and ask which stage, concept, or theorist it demonstrates.
Cognitive development
- Piaget: sensorimotor (0–2, object permanence, transition to symbolic thought); preoperational (2–7, egocentrism, centration, irreversibility, failure at conservation); concrete operational (7–11, conservation, classification, seriation, but no abstract reasoning); formal operational (11+, hypothetical and abstract reasoning).
- Assimilation fits new information into an existing scheme; accommodation changes the scheme.
- Vygotsky: zone of proximal development and scaffolding; private speech is a self-regulatory tool, not egocentrism.
- Theory of mind, tested with false-belief tasks, typically emerges around age 4.
Language
- Sequence: cooing, babbling, one-word (holophrastic), telegraphic two-word speech, then grammar. Overregularization ("goed," "mouses") shows rule learning rather than imitation.
- Children deprived of language input during the critical period show persistent deficits.
Social and moral development
- Attachment (Bowlby; Ainsworth's Strange Situation): secure, insecure-avoidant, insecure-ambivalent, disorganized. Harlow's monkeys preferred the cloth mother, showing contact comfort beats feeding.
- Parenting styles: authoritative (high warmth, high control) predicts the best outcomes; authoritarian, permissive, and uninvolved are the alternatives.
- Kohlberg: preconventional (punishment, self-interest), conventional (approval, law and order), postconventional (social contract, universal principles). Gilligan criticized the framework for undervaluing an ethic of care.
- Erikson's psychosocial stages run from trust versus mistrust to integrity versus despair.
Worked example
A 4-year-old watches water poured from a short wide glass into a tall narrow one and insists the tall glass holds more. Reasoning: the child is preoperational. She centers on height, ignores width, and cannot mentally reverse the pouring; conservation of liquid typically appears in the concrete operational stage around age 7. This is not a perceptual problem, since she sees the same amount, but an inability to coordinate two dimensions at once.
Traps
- Confusing assimilation with accommodation.
- Assigning conservation to preoperational children, who fail it by definition.
- Confusing Erikson's industry versus inferiority (school age) with identity versus role confusion (adolescence).