This fear is then reduced by avoidance and compulsive rituals (for example, washing) that serve as an escape from distress and, in doing so, are negatively reinforced (that is, they become habitual). The entire emotional response was extinguished after several extinction trials in which the height of the hurdle made it impossible to jump over and the light was exposed. When the light was turned on and the dog realized he couldn’t jump over he displayed strong signs of a fear response until he finally calmed down without the slightest hint of distress. This experiment influenced behaviourally oriented researchers in adapting similar treatment to human beings with OCD. They were expected to confront for 2 hours each day situations and stimuli they usually avoided. The purpose of this confrontation was to induce obsessional fears and urges to ritualize. Patients were also asked to refrain from performing compulsive rituals such as washing, for example, after exposure. (Abramowitz)
Contemporary ERP (Exposure and Response Prevention) entails therapist-guided, systematic, repeated and prolonged exposure to situations that provoke obsessional fear, along with abstinence from compulsive behaviours. This can occur in the form of actual exposure or imaginal exposure. Refraining from compulsive rituals is a vital component of treatment because the performance of such rituals to reduce obsessional anxiety would prematurely discontinue exposure and rob the patient of learning two things. First, that the disorder is not truly dangerous and second that anxiety subsides on its own even if the ritual is not performed. Thus successful ERP requires the patient to remain in the exposure situation until the obsessional distress decreases spontaneously without attempting to reduce distress by withdrawing from the situation or by performing compulsive rituals or neutralizing strategies. (Abramowitz)
ERP is generally considered the treatment of choice for OCD with approximately 75-85% of patients experiencing a considerable reduction after taking on this type of treatment. There are two types of ways for administering ERP for OCD. Therapist-controlled ERP, as mentioned previously, is used if the response sought is prevention and it is administered by the patient being coached by the therapist, usually in his own home. The second type of ERP is self-controlled ERP which are sessions that are carried out as homework assignments in between therapy sessions. Data on which one of these two are the most effective have not yielded a clear-cut answer. (van Oppen)
A more detailed example of therapist-controlled ERP format follows a few hours of assessment and treatment planning followed by 16 twice-weekly treatment sessions lasting about 90 to 120 minutes each and spaced over about 8 weeks. Generally, the therapist supervises the exposure sessions and assigns self-exposure practice to be completed by the patient between sessions.