Developmental psychology – the study of neural, cognitive, and socioemotional human development – has provided us with some of our deepest insights into human plasticity, our ability to change even the physical structure of our brains to adapt to new challenges. The French psychologist Jean Piaget is generally recognized as the father of developmental psychology – and as our brains and consciousness are most flexible and rapidly developing during childhood, it’s not surprising that his research focused on children. Piaget mapped out stages of cognitive development through which the child grows from a sensory infant, to a toddler unsure of the boundaries between her imagination and the external world, to an older child able to manipulate complex abstractions like algebraic formulas.