Classical conditioning The process of closely associating a neutral stimu- lus with one that evokes a reflexive response so that eventually the neutral stimulus alone will evoke the same response.
Classical conditioning is an important concept in the school of psychology known as behaviorism, and it forms the basis for some of the techniques used in be- havior therapy.
Classical conditioning was pioneered by the Russian physiologist Ivan Pavlov (1849-1936) in the 1890s in the course of experiments on the digestive systems of dogs (work which won him the Nobel Prize in 1904). Noticing that the dogs salivated at the mere sight of the person who fed them, Pavlov formulated a theory about the relationship between stimuli and responses that he believed could be applied to humans as well as to other animals. He called the dogs’ salivation in response to the actual taste and smell of meat an unconditioned re- sponse because it occurred through a natural reflex with- out any prior training (the meat itself was referred to as an unconditioned stimulus). A normally neutral act, such as the appearance of a lab assistant in a white coat or the ringing of a bell, could become associated with the ap- pearance of food, thus producing salivation as a condi- tioned response (in response to a conditioned stimulus).Pavlov believed that the conditioned reflex had a physiological basis in the creation of new pathways in the cortex of the brain by the conditioning process. In further research early in the 20th century, Pavlov found that in order for the conditioned response to be main- tained, it had to be paired periodically with the uncondi- tioned stimulus or the learned association would be for-
gotten (a process known as extinction). However, it could quickly be relearned if necessary.
In humans, classical conditioning can account for such complex phenomena as a person’s emotional reac- tion to a particular song or perfume based on a past expe- rience with which it is associated. Classical (sometimes called Pavlovian) conditioning is also the basis for many different types of fears or phobias, which can occur through a process called stimulus generalization (a child who has a bad experience with a particular dog may learn to fear all dogs). In addition to causing fears, however, classical conditioning can also help eliminate them through a variety of therapeutic techniques. One is sys- tematic desensitization, in which an anxiety-producing stimulus is deliberately associated with a positive re- sponse, usually relaxation produced through such tech- niques as deep breathing and progressive muscle relax- ation. The opposite result (making a desirable stimulus unpleasant) is obtained through aversion therapy, in which a behavior that a person wants to discontinue— often an addiction, such as alcoholism—is paired with an unpleasant stimulus, such as a nausea-producing drug.
Further Reading Gormezano, Isidore, William F. Prokasy, and Richard F.
Thompson. Classical Conditioning. 3rd ed. Hillsdale, NJ: L. Erlbaum, 1987.
Lieberman, David A. Learning: Behavior and Cognition. Bel- mont, CA: Wadsworth Publishing Co., 1990.
Mackintosh, N.J. Conditioning and Associative Learning. New York: Oxford University, 1983.
Client-centered therapy An approach to counseling and psychotherapy that places much of the responsibility for the treatment process on the patient, with the therapist taking a non-directive role.
Developed in the 1930s by the American psycholo- gist Carl Rogers, client-centered therapy—also known as non-directive or Rogerian therapy—departed from the typically formal, detached role of the therapist common to psychoanalysis and other forms of treatment. Rogers believed that therapy should take place in the supportive environment created by a close personal relationship between client and therapist. Rogers’s introduction of the term “client” rather than “patient” expresses his rejection of the traditionally authoritarian relationship between therapist and client and his view of them as equals. The client determines the general direction of therapy, while the therapist seeks to increase the client’s insightful self- understanding through informal clarifying questions.