Studying development
Developmental psychologists study how people change and stay the same from conception to old age.
Key questions
Three debates shape the field. Nature versus nurture asks how much genes and environment each contribute. Continuity versus discontinuity asks whether development is gradual or happens in distinct stages. Stability versus change asks how much personality and traits remain the same over a lifetime. Most psychologists now see genes and environment interacting.
Prenatal development
Prenatal development has three stages: the germinal stage (the first two weeks), the embryonic stage (weeks 3 to 8, when major organs form), and the fetal stage (from week 9 to birth). Teratogens are harmful substances, such as alcohol, that can cause birth defects; fetal alcohol spectrum disorders are a preventable result of drinking during pregnancy.
Research designs
Cross-sectional studies compare people of different ages at one time, which is quick but can confuse age effects with generational differences. Longitudinal studies follow the same people over years, revealing true change but taking much longer and losing participants over time.
Flashcard
Debate over genes versus environment in development
Check your understanding
A researcher studies the same group of children from age 3 to age 30. This is a: