Final answer:
Jean Piaget is the psychologist known for his theory of the four stages of cognitive development, focusing on children's cognitive growth and the impact of social interactions.
Step-by-step explanation:
The individual known for his stages of cognitive development, a framework describing how students intellectually develop through various stages, is Jean Piaget. Piaget's theory outlines four stages of cognitive development: sensorimotor, preoperational, concrete operational, and formal operational. His approach indicated a discontinuity in development, whereby as children progress to a new stage, there is a significant shift in how they think and reason. This stands in contrast to other developmental psychologists like Sigmund Freud, who highlighted the psychosexual stages of development, and Erik Erikson, who presented a theory of psychosocial development, with personality changes occurring throughout the lifespan. Piaget's focus was unique in that he concentrated primarily on children's cognitive growth and the role of social interactions in that development.