While behavior therapies can be very effective, only two-thirds of patients complete treatment. Often, this occurs because patients are unwilling to experience the intense distress that can accompany an exposure exercise. In addition - and perhaps most importantly - many patients do not fully understand the rationale behind exposure-based treatments, and thus have trouble sticking with it when things get tough.
Habituation is a Natural Process
Exposure-based treatments take advantage of a natural process called habituation. Habituation is a form of learning whereby a person will stop responding or paying attention to a stimulus (e.g., thought, object, place, people or action) with repeated exposure.
Everyday life is full of examples of habituation. For instance, when people first move to a neighborhood they may be aggravated by the noise of a busy highway that runs near their house. However, with each passing day the noise from the highway fades into the background until it is no longer noticed. In this instance, the person has become habituated to the sound of the highway.
Habituation is the key to Exposure Therapy
Exposure-based behavior therapies work by promoting habituation to things that are feared (e.g., thoughts, objects, people or actions) through the creation of opportunities to "unlearn" dangerous or threatening associations.
At the same time, exposure-based therapies reduce avoidance, which reinforces fearful thoughts. Indeed, avoiding things we are afraid of sends a very powerful message that there really is good reason to fear such things and that we do not have the skills to cope with them. Let's look at a practical example to see how exposure works to promote habituation.
Imagine that you have a fear of dogs. Now picture yourself on a sidewalk as someone approaches you with their dog. As the dog approaches your anxiety will start to rise. If you run away, your anxiety will subside immediately but you will be teaching yourself that you cannot handle dogs, that the distress dogs cause you is intolerable and that avoidance is the only way to stay safe. Avoidance would keep you stuck being afraid of dogs forever, as you would never get a chance to unlearn this fear and challenge these beliefs.
If, on the other hand, you did not run away but instead let the dog come up to you, your anxiety would go higher than you are used to, for longer than you are used to; however, with time - provided the dog did not bite you - your anxiety would decrease through the natural process of habituation.
If you met this dog on the sidewalk every day for a month without incident, your brain would continue to "unlearn" its fear of dogs and your level of anxiety would decrease. At the same time, what distress you did experience would disappear more and more quickly. Eventually, you would feel no distress at all when encountering the dog - you might even enjoy spending time with him. In short, you would be habituated to the dog.
Using Habituation and Exposure in Treatment for OCD
Exposure exercises in behavior therapy for OCD operate on the same principles as those illustrated in the above example. Essentially, patients are exposed to feared objects (e.g., a contaminated door handle) or thoughts (e.g., thoughts of a loved one dying in a car crash) over and over again until their anxiety has decreased.
Importantly, patients are prevented from engaging in rituals or compulsions during the exposure. Rituals are a form of avoidance that prevents you from "unlearning" your fear and realizing that you can, in fact, cope with the anxiety caused by obsessions. As you are repeatedly exposed to the thing you are afraid of and no adverse consequences occur, your fear will dissipate.
Of course, as in the example of the dog, such exposures require you to tolerate your anxiety being higher than you are used to, for longer than you are used to. However, once this short-term discomfort passes, in the long term your fear will subside and you will no longer need to engage in the rituals or avoidance that dominate your life.
In summary, exposure-based therapies offer a simple and effective way to reduce symptoms of OCD - but they require courage and you have to be willing to give them a chance to work.