The early behaviorist John Watson described habits as behavioral patterns formed through the repeated association of stimulus and response pairs. The functionalist researcher B.F. Skinner preferred the term (operant) conditioning.
Watson devised classical conditioning experiments similar to Pavlov's work on dogs, but the American scientist used human subjects. His most famous subject is known as Little Albert, a baby whom Watson conditioned to produced a fear response to the stimulus of a white rate. Little Albert formed the habit of crying and moving away when shown the rat.
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