Important Contributions to Psychology Give a brief definition of why each person is important to the category mentioned. History and Approaches Person Mary Whiton Calkins Importance Charles Darwin Dorothea Dix Sigmund Freud G. Stanley Hall William James Ivan Pavlov Jean Piaget Carl Rogers B.F. Skinner Margaret Floy Washburn John B. Watson Wilhelm Wundt Biological Bases of Behavior Person Paul Broca Importance Charles Darwin (repeat) Michael Gazzaniga Alexander Luria Roger Sperry Carl Wernicke Sensation and Perception Person Gustav Fechner Importance David Hubel (with Wiesel) Ernst Weber Torsten Wiesel (with Hubel) Cognition Person Noam Chomsky Hermann Ebbinghaus Wolfgang Kohler Importance Elizabeth Loftus George A. Miller George Sperling Benjamin Whorf