Psychology is considered a relatively new discipline in the study of behavior. The discipline as a science might be attributable to one Wilhelm Wundt, also considered the founder of structural psychology. His doctrine, which his student Edward Titchener called structuralism, stressed the framework through which thought and mind operate. It emphasizes three things: consciousness, the formation of experience and the mind's inner workings to project that experience.
Perhaps most famous of the schools of psychology is psychoanalysis as pioneered by Sigmund Freud. His theories were built on the work of others, but his summations became the most famous. He originally started out on a career in neurology research, though the private practice he would open later dealt in psychopathology. His most well-known ideas revolved around the unconscious mind and the sexual elements of individuals' upbringing. He extrapolated from the ideas of William James, theorizing that there was a consciousness and a repository for information and repressed memories that he termed the unconscious. He hypothesized that a pre-conscious stage served in bringing such repressed memories or new ideas into the conscious state. He later amended his ideas by adding the elements of the hedonistic, impulsive id and the moralistic, ethical part of the psyche called the super-ego. These two, almost akin to the shoulder-sitting demon and angel, are moderated by the ego, that produces a practical action based on the ideas from the other two elements of the psyche. His development of psychoanalysis relied primarily on the concept of repression, recommending a developed "talk therapy" that would seek out long dormant memories or ideas. Many of his methods were a response to hypnosis, which he deemed weak and unreliable as a method of uncovering psychological ills.
One of his most famous disciples was Carl Jung, who developed a number of core concepts in what is today considered basic psychology. The concepts of introversion and extraversion are attributed to his work. Additionally, he hypothesized that social norms are developed out of archetypes, a stereotypical perception of some concrete or abstract concepts that informs an individual's presumptive thoughts. This concept is viewed as critical in his theories of the collective unconscious, a concept in social psychology that hypothesizes that the histories and surroundings of a community inform its political views, aspirations and values. However, Jung believed there was a biologically inherited component to the idea and not merely a construct learned later. The ideas however resemble the idea of collective memory.
Behaviorism, pioneered by other major psychologists, underwent its most radical and notable shifts under B.F. Skinner. Skinner was a researcher of what is called radical behaviorism, which he distinguished in terms of positive reinforcement and negative reinforcement. Respectively, behavior would be conditioned via reinforcement. The positive reward of something abstract like praise or something tangible constitutes positive reinforcement, while the removal of a desirable or necessary thing would constitute negative reinforcement. He researched operant conditioning and is also famous for the invention of the operant conditioning chamber, the environment of which is altered by the researcher in response to the subject's behavior within the chamber.
The humanistic school of psychology is represented by Carl Rogers and Abraham Maslow. Humanistic psychology itself views every individual, thus every case, as unique, and every subject as having an achievable potential by way of making rational choices. Abraham Maslow emphasized a hierarchy of needs from which individuals obtained the tools and experience necessary for "self-actualization," realizing one's full and maximum potential. He worked with an emphasis on studying individuals whose life experiences varied; he particularly included the most highly achieving members of society. Rogers came to create the most widely used form of talk psychotherapy today, which emphasizes an unconditional positive regard for the patient from a non-judgmental therapist in an extremely comfortable environment. However, his colleague Rollo May came to form a more neutral, less than positive, view of human nature. His ideas formulated the basis of existentialist psychology, heavily influenced by existentialist philosophers. Viktor Frankl, a Holocaust survivor who emphasized the pursuit of meaning in life as a source of anxiety, developed logotherapy as a subsection of these views on psychology, which viewed all experience in life and all pursuits to be part of every individual's efforts to pursue meaning.