Developmental psychology (lifespan physical, cognitive, and social development)
This domain asks you to place a described behavior at the right developmental stage and to distinguish normal variation from delay. Most items hinge on one signature milestone plus its underlying cognitive limit.
Physical and prenatal development
- Prenatal stages: germinal (about 2 weeks), embryonic (weeks 3 to 8, organogenesis, most vulnerable to teratogens), fetal (9 weeks to birth). Alcohol, rubella, and mercury do the most structural damage in the embryonic period.
- Motor milestones follow cephalocaudal (head to tail) and proximodistal (center to outward) sequences.
- Aging: vision and hearing decline, reaction time slows; crystallized intelligence holds while fluid declines. Dementia is pathological, not normal aging.
Cognitive development
- Piaget: sensorimotor (0 to 2, object permanence emerges around 8 months), preoperational (2 to 7, egocentrism, centration, failure of conservation), concrete operational (7 to 11, conservation, reversibility, classification), formal operational (11 and up, abstract and hypothetical reasoning).
- Vygotsky: development is social; zone of proximal development and scaffolding; language shapes thought.
- Information processing: working memory capacity and processing speed increase; automaticity frees resources.
Social and emotional development
- Attachment (Bowlby, Ainsworth): secure, insecure-avoidant, insecure-resistant, disorganized, classified with the Strange Situation. Harlow showed contact comfort outweighs feeding. Sensitive caregiving predicts secure attachment.
- Temperament (Thomas and Chess: easy, difficult, slow-to-warm-up) is biologically based but modifiable through goodness of fit.
- Baumrind parenting: authoritative (high warmth, high demand) predicts the best outcomes; authoritarian (low warmth, high demand); permissive (high warmth, low demand); uninvolved.
- Erikson: trust versus mistrust, autonomy versus shame, initiative versus guilt, industry versus inferiority, identity versus role confusion, intimacy versus isolation, generativity versus stagnation, integrity versus despair.
- Kohlberg: preconventional (punishment, self-interest), conventional (approval, law and order), postconventional (social contract, universal principles). Gilligan argued care-based reasoning was undervalued. Marcia's identity statuses: diffusion, foreclosure, moratorium, achievement.
Worked example
A 5-year-old watches liquid poured from a wide glass into a tall narrow one and says the tall glass holds more. Reasoning: this is a preoperational failure of conservation caused by centration on height and absent reversibility. If she says pouring it back makes it equal, she is using reversibility, a concrete-operational skill.
Traps
Putting object permanence in the preoperational stage; treating Piaget's stages as exact ages rather than a sequence; confusing conventional with postconventional reasoning; labeling disorganized attachment as merely clingy.