History

Beginning of Scientific Psychology
Wilhelm Wundt founded the first laboratory dedicated to psychological research in 1879 at Leipzig University in Germany. The book, "Principles of Psychology" was published on 1890 by William James. Sigmund Fraud invented the method called psychotherapy which focused on sexuality and the unconscious mind.
Behaviorism
Founded by John B. Watson in the early 20th century. It was considered as a psychological guiding theory that grounded in the studies of animal behavior.
Existential - Humanist Movement
It was developed in the 1950's in reaction to both behaviorism and psychoanalysis. It focuses on unique human issues and the fundamental issues of life like death. The important theories in this era was the human heirarchy of needs by Abraham Maslow and the Client centered therapy by Carl Rogers.
The Rise of Cognitivism
Links between the brain and the nervous system were being understood. Cognitive science was created to provide an umbrella that would construct the efforts of philosophy, computer science and neuroscience.