Stampfl's approach is most easily understood in the light of recent experimental work on animal avoidance behavior. A dog, for example, is confined in a cage that is divided in two. A low wall separates the two halves of the cage, over which the dog can jump. On one side there is a bell that rings just before the dog receives an electric shock. The dog promptly learns that he can avoid the shock by jumping to the other side of the cage. Soon he will learn to do this automatically, whenever the bell rings. What is significant from a psychologist's point of view is that the dog will continue for a long time to jump to the opposite side of the cage, even once no further shocks are given. The dog's fear is maintained in force only by his own memory. Animal psychologists have found a quick way to end the dog's fear: ring the bell, but _prevent_ the dog from jumping to the other side of the cage. Once the anxiety-stricken animal realizes that he is no longer going to be shocked, the old habit based on fear simply disappears. Implosive therapists make use of an equivalent technique with human beings. Patients are asked to imagine, as vividly as {166} possible, that they are facing the very thing they chronically have tried to avoid. For example, an individual may have suffered from a terrifying fear of elevators for years. The therapist tries to use exaggerated imagery to produce maximum anxiety. He might ask the patient to imagine being stuck in an elevator fifty floors up, having the elevator shake and abruptly fall a foot, then have the lights go out, and so on. By _maintaining_ this contrived elevator nightmare long enough, implosive therapists claim that, frequently, the level of anxiety of patients quickly and dramatically falls, and they lose their exaggerated fears. Implosive therapists are therefore not primarily concerned with being genuine, sympathetic, or mothering. They focus their energy and attention on pushing clients to confront the worst fears and catastrophes they can imagine. All the while, clients are aware both that the intense anxiety they experience is an _intended_ goal of therapy and that the therapist is convinced they are much stronger than they have thought. Implosive therapy is usually done on an individual basis and is comparatively brief, usually lasting less than a dozen sessions. It should be mentioned that, when not successful, implosive therapy may occasionally _sensitize_ clients to feel even more anxiety than they did at the outset. It therefore tends to be a higher-risk treatment, but it can be remarkably effective. Visualizing anxiety-producing events also has successfully been used by individuals on their own. (For more information, see "Appendix B: Suggestions for Further Reading.") _Applications of Implosive Therapy_