Which Swiss psychologist who studied cognition in children identified stages of development and contributed to schema learning?

• A. Jean Piaget
• B. Noam Chomsky
• C. Lev Vygotsky
• D. B.F. Skinner

Answer: (A)

Understanding how children's thinking develops in distinct stages and how they build and revise mental structures is what this item tests. Jean Piaget, a Swiss psychologist, is the thinker behind that work. He described cognitive development as a sequence of stages—the sensorimotor, preoperational, concrete operational, and formal operational stages—each representing a qualitatively different way of thinking. Central to his theory is the idea that children organize knowledge into schemas (or schemes) and adapt those schemas as they interact with the world through assimilation and accommodation. This focus on internal cognitive change with age marks Piaget as the key figure in this area. The other names listed are important in related fields, but they did not lay out a stage-based theory of cognitive development or emphasize schema learning in the same way.