Exposure and response prevention (ERP) therapy, sometimes referred to as simply exposure therapy, is the treatment of choice in the professional literature and practice for helping individuals with OCD.
ERP is set up on a hierarchy, meaning patients work with a therapist to list all of their fears, and then they rank those fears from least to most anxiety-provoking. Starting with one of the lower level fears, a therapist works with the person, and together they engage the feared experiences. So if a therapist is treating someone with OCD related to fears of contamination, they will work together to create a hierarchy about what “dirty” things are feared. After they make and rank that list, they will then go and expose themselves to the listed items (most ERP therapists will do this with their patients).
Let’s say that touching the floor is a medium level of anxiety for a person because they feel that the floor is contaminated. A therapist will suggest to the person an exposure exercise and then get a level of anxiety from the person on a 0–10 scale; the therapist will then continue to assess the person’s anxiety at frequent intervals during the exposure.
They may start with kneeling on the floor and then sit on it. Next they may touch it with one finger, then two, then the whole hand, and then both hands, and so on until they are actually lying on the floor together. This may take an hour, or it may take twenty hours. Either way, the goal is to be constantly moving up the hierarchy to confront higher and higher levels of fear (see “Sample Hierarchy for Fear of Contamination” later in this answer).
Therapists hope to achieve a few things with ERP. First, they do not just expose a person to a situation and then run away, both patient and therapist have to stay in the situation until the person’s anxiety is reduced to at least half of what it was when they started. This allows people to realize that they can do what they fear and see their anxiety decrease. Further, the individual needs to do this repeatedly, one time is not enough. The goal is to change a behavior, and it can take many repetitions before a new behavior is really ingrained. Doing an exposure also shows the patient that what he is doing is not really dangerous, since the therapist is willing to do it with him. If it really were dangerous, the therapist would not do it because it would be too much of a risk.
So ERP works by having people do what they fear, stay in the situation until they are no longer anxious or have reduced their anxiety level by half, and realize that just because they experience fear does not mean that anything bad will happen to them. Doing ERP can decrease compulsive behaviors by both inhibiting the rituals and challenging the validity of the obsessional thoughts.
Sample Hierarchy for Fear of Contamination
• Putting on shoes
• Picking up items that have been on the floor for under five seconds
• Seeing people sit on the floor
• Kneeling on the floor
• Walking on the floor with socks on
• Vacuuming the floor
• Sitting on the floor, but not touching it
• Picking up items that have been on the floor for under twenty seconds
• Watching babies crawl on the floor
• Petting a dog that has been lying on the floor
• Touching the sides of shoes
• Touching the floor
• Sitting on the floor and touching it
• Lying on the floor
• Picking up items that have been on the floor for more than twenty seconds
• Touching the soles of shoes