What field studies the changes throughout a person's lifespan?

Developmental psychology focuses specifically on the systematic study of the changes that individuals experience throughout their lifespan, from infancy through old age. This field examines a variety of aspects including physical, cognitive, emotional, and social development. Developmental psychologists are interested in how people change and grow in response to biological, environmental, and social influences.

The other areas of psychology, while important, concentrate on different aspects of human behavior and thought. Cognitive psychology primarily investigates mental processes such as perception, memory, and problem-solving. Behavioral psychology centers on observable behaviors and the ways they can be influenced by the environment. Social psychology studies how individuals' thoughts, feelings, and behaviors are influenced by the presence and actions of others, focusing on social contexts rather than individual development over time. Therefore, developmental psychology is the most appropriate field to study changes throughout a person's lifespan.