Behaviorism
Behaviorism was introduced into American psychology by John B. Watson in the early 20th century. The behaviorists focused their study on observable behavior because they believed that the operation of mind was like an assembly line, which only processed concrete parts. They regarded the acquisition of information as discovering and retrieving outcomes rather than an internal process. These beliefs led them to formulate a stimulus - response theory of psychology. In this theory, all complex forms of behavior, including emotions and habits, should be observed and meaured with scientific method.
There are three theoriests mainly representing this school: John B. Watson, B. F Skinner, and Edward L. Thorndike. Watson was the father of behaviorism. Skinner, the radical behaviorist, invented his well-known "skinner box" as a device for faciliating experimental observations. Thorndike originated his theory of "connectionism" and formulated his laws of learning. Besides these, behaviorism made other contributions as well, such as the Audio-Lingual Method for foreign language teaching.
Other resources:
http://encarta.msn.com/index/conciseindex/00/00015000.htm
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