The document discusses key concepts in lifespan developmental psychology including:
1) Development involves biological, social, cognitive, and personality changes across the lifespan from conception to death.
2) There are debates around nature vs nurture and whether development is continuous or occurs in distinct stages.
3) Early prenatal development and environmental influences can impact lifelong physical and psychological development.
4) Infants progress from reflexes to language development and form attachments with caregivers that shape social and emotional development.