Classical conditioning changes reflex behavior that, in the absence of any learning, would occur only in response to specific stimuli, such as salivation in the presence of food (Kagan & Havemann, 1996). Classical conditioning capitalizes upon reflexes that are built in and not learned per se. It is defined by Kagan and Havemann (1996, p. 569) as "a type of learning process through which a response becomes attached to a conditioned or previously neutral stimuli." Operant conditioning, in contrast, refers to "the process by which, through learning, free operant behavior becomes attached to specific stimuli" (Kagan & Havemann, 1996, p. 578).
Classical conditioning procedures expose an individual to specific stimuli and then reinforce the desired response to those stimuli. Operant conditioning works on pre-existing behaviors, using stimuli to attach the behavior to specific inputs. They are both useful in learning environments and in fostering the development of new, desired behaviors; however, classical conditioning may be most useful in extinguishing undesired behaviors through negative reinforcement. Operant conditioning works on relatively free operant behavior as opposed to behaviors that are engendered in the subject through the application of some type of external stimuli or event that is then associated with a response (Kagan & Havemann, 1996).
Kagan,J., & Havemann, E. (1996). Psychology. New York: Harcourt
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