Through systematic observation of one's own conscious experience, subjects were exposed to different visual stimuli, optical illusions and auditory tones, and then made to analyze what they experienced ("Timeline," n.d.).
Functionalism evolved as a reaction to structuralism. This school of thought was greatly influenced by the work of William James, the father of American psychology, and the evolutionary theory of Charles Darwin (Wagner, n.d.[b]). Functionalism was a more systematic and accurate method than structuralism in that the former focused on the purpose of consciousness and behavior while the latter focused on the elements of consciousness. Functionalism gave due consideration to individual differences, with a great deal of impact on education, supporting the view that "children should learn at a level for which they are developmentally prepared" (Wagner, n.d.[b]).
According to behaviorism, all behaviors are acquired through conditioning, which happens through interaction with the environment, and behavior can be studied in a systematic, observable manner regardless of internal mental states (Wagner, n.d.[c]). There are two types of conditioning. Classical conditioning is a method whereby a naturally occurring stimulus is paired with a neutral stimulus so that eventually the latter evokes the same response as the former without the presence of the former. Operant conditioning uses rewards and punishments for behavior. Behaviorism does not consider free will or internal factors like moods, feelings and thoughts. The theory does not consider learning that does not use rewards and punishments. The adaptability of an individual in the face of new information is also not considered.
Psychoanalysis, founded by Sigmund Freud, focused on the influence of the unconscious mind on behavior (Wagner, n.d.[a]). The six basic assumptions of the psychoanalytic theory are that unconscious mental processes exist, that all human behavior is motivated and purposeful, that past experiences influence current changes and reactions, that personality functioning is very complex and can be understood through the Id, Ego and Superego, that thinking processes involve energy, strength and force, and that human behavior is influenced by interaction with the environment ("Timeline," n.d.).
Humanists like Carl Rogers consider people to be basically good or healthy and they see mental health as the normal progression of life; any distortion to this natural tendency is called self-actualization. According to Rogers, people naturally know what is good for them, and what leads them astray is the society with its conditions of worth, often leading to discontent when they do not reach the standards applied to them by others. This disparity between the real self and the ideal self is called incongruity (Boeree, 2003). A healthy individual involves the following qualities: openness to experience; living in the present; organismic trusting, doing what feels right and comes natural; freedom and taking responsibility for one's choices; and creativity.
Gestalt psychology evolved in response to the