Final answer:
The scientific study of conscious experience within psychology is most closely associated with Wilhelm Wundt and the structuralist approach, which used introspection to analyze the components of consciousness. This contrasts with behaviorism, which focuses on observable behavior and was advanced by psychologists like John B. Watson.
Step-by-step explanation:
The notion that the subject matter of psychology should be the scientific study of conscious experience is most closely linked with Wilhelm Wundt and the approach known as structuralism. Wundt, often recognized as the father of experimental psychology, advocated for the study of consciousness using introspection, which involves examining one's own conscious experience as objectively as possible. This approach aimed to dissect the conscious experience into its basic elements.
Structuralism contrasted with behaviorism, an approach popularized by John B. Watson, which rejected the study of consciousness in favor of observable behavior. Watson, along with Ivan Pavlov and B.F. Skinner, believed that psychology should primarily involve the study of outward behavior since internal mental states were not objectively measurable. This focus on the external allowed for more empirical rigor and control in experimental design, commonly using animals as subjects in behavioral experiments.