The whole human lifespan,
one unit at a time.

Go beyond the definitions. Each unit digs into the connective tissue: why a theory mattered, what modern research has shown, where the old ideas turned out to be wrong, and how concepts link together across the whole lifespan.

Do the interactives. Reading is recognition; retrieval is learning. The quizzes and matching drills are built for active recall — the single best-supported study tactic in cognitive science.

Look for the colored callouts. Go deeper boxes take an idea further, Update boxes flag where the science has moved, and Myth boxes bust the classics.

Work at your own pace. Units run birth to death, left to right, but each one stands on its own — start wherever your curiosity (or your syllabus) takes you.