Dr. Chang's views reflect the perspective of developmental psychology. Developmental psychology is the scientific study of how and why human beings change over the course of their life. It focuses on the development of individuals from infancy to old age, including physical, cognitive, and social development. In Jiang's case, Dr. Chang suggests that his predisposition for ADHD may be due to his father's medical history, which is a developmental perspective that considers the influence of genetics and environment on an individual's development.