Exposure and response prevention for OCD

Summary

Exposure and response prevention (ERP) is the most clearly demonstrated evidence-based psychological treatment for OCD. It shares the same basic principles as other forms of exposure therapy, but its practice stresses certain elements that are particularly important in OCD. This includes the importance of response prevention and the resulting principle of re-exposure. ERP may by some therapists be perceived as more challenging than exposure therapy for other type of anxiety problems. This can be due to the patient’s poor insight or that certain themes such as religious and sexual obsessions may be experienced as more difficult to deal with by the therapist.

Background

In the 1960s Victor Meyer developed ERP which still today, with some modifications, is the primary evidence-based psychological treatment for obsessive-compulsive disorder. ERP has since been further developed by other clinical researchers, including Edna Foa and Jonathan Abramowitz.

Principles and practice

The specific exposure therapy for obsessive-compulsive disorder (OCD) is exposure and response prevention (ERP). As for other forms of exposure, the theoretical basis that guides ERP is functional analysis (see separate article). In such an analysis, an obsession is identified as the part of the antecedent that triggers anxiety or fear, whereas the compulsion is identified as the behavior, whose function is to relieve anxiety or discomfort. Another way to say the same thing is that compulsions become more and more frequent because they are negatively reinforced.

ERP mainly includes exposure in-vivo for external stimuli that evoke obsessions (such as touching something that evokes obsessions of contamination) but may also include imaginal exposure (such as imagining the door to one’s house being unlocked). So what is then different from “normal” exposure – more precisely, what is “response prevention”? The short answer to that question is that response prevention simply means helping the patient to abstain from what in other contexts are called safety behaviours (see separate article). In the context of OCD, this means refraining from doing compulsions.

The probably most common clinical example of an ERP exercise (for contamination OCD), would be helping the patient to touch for instance a door handle (which evokes obsessions about contamination within the patient such as “There is a lot of bacteria that will get on my hands, I will become sick”) and subsequently helping the patient _not_ to wash his hands afterwards (that is, prevention of the compulsion, or ritual – ERP can also mean “exposure with ritual prevention”). This will make it possible for the patient to experience something new: even if he doesn’t perform his washing ritual, his fears will subside with time, he will have learnt something new.

The five principles of exposure

As with all exposure, exposure with response preventionfollows 5 principles. For it to be effective, exposure should be:

• planned and structured (by the therapist, in collaboration with the patient)

• gradual (by way of a exposure hierarchy, introduced by the therapist in collaboration with the patient)

• prolonged (that is, be sufficiently long as to enable new non-fearful experiences)

• repeated (that is, be done a sufficient number of times, which also enables experiencing something new over time)

• without safety behaviours (without rituals or compulsions) - this is what "response prevention" means!

And as with all other exposure therapy, ERP has three main phases:

1. Initial assessment and preparatory phase

2. Exposure phase

3. Evaluation and relapse-prevention phase

(see separate article on Exposure in-vivo)

And as in all other exposure, during exposure, the therapist will ask questions like “What goes through your mind right now” (to help identifying safety behaviours or subtle mental compulsions, such as saying a prayer or repeating “It is only an obsession, It is only an obsession!”, “The doctor said I won’t get sick, The doctor said I won’t get sick!”). The therapist will also guide the patient by asking him or her to focus on the anxiety provoking stimulus (“Try to touch it with your hand and don’t let go until I say so”). The therapist also wants to continually assess the patient’s level of anxiety (“What is your level of anxiety at this moment?”) and provide support (“I can see how difficult this is for you, you are so brave!”).

In a strict sense, sometimes therapy consists mainly of response prevention, with no specific exposure exercises proposed by the therapist. Again, by “exposure” here is meant a specific therapeutic exercise (see separate article “Exposure”), not “exposure” in the everyday language sense of being randomly or naturally exposed to something during an ordinary day. An example of such “natural exposure” and consequent response prevention (that is, not including exposure as a specific, sought out therapeutic exercise) could be a patient working on leaving his house without checking 20 times that the door is actually locked. In this case, no formal exposure exercise is done, he is “naturally” exposed to obsessions about the door not being locked every time he leaves his house, and the therapeutic exercise is one of response prevention.

As with other types of exposure, ERP needs to be prolonged for it to actually work. In OCD, this often poses a practical problem: In the example of ERP for contamination OCD given above (the exercise when the patient touches the door handle, evoking obsessions and anxiety), sooner or later, the patient will eventually have to wash his hands (for instance, when he goes to use the bathroom, or before he prepares food for dinner). That is, it is self-evident that ERP cannot prevent the patient from ever washing his hands ever again. The fact that the patient sooner or later _will_ wash his hands, raises a challenge in ERP. This challenge can be stated like this: For the patient with OCD, the hand-washing has two very different functions (see separate article on Functional analysis): On the one hand, it has the same function as for all of us (after having been to the bathroom to defecate, we usually wash our hands). On the other hand, for the patient with OCD that made an exposure exercise of touching the therapist’s door handle two hours earlier going to the bathroom to defecate, the hand-washing also serves an additional function, not functionally related to the defecation but to the earlier exposure exercise: He will “wash away” his anxiety triggered by the exposure exercise, that is, the hand-washing will _also_, for the OCD-patient, constitute a compulsion. And all compulsions maintain the suffering by maintaining OCD.

Re-exposure

This practical problem (maintaining prolonged exposure in ERP while still of course not forbidding the patient to eventually during the day wash his hands after having been to the bathroom to defecate and/or before preparing food for dinner etc) is solved through the ERP technique of re-exposure. It simply involves instructing the patient to re-expose himself to a stimulus conditioned with fear and obsessions after having washed his hands. For instance, if the door handle in the patient’s home is also conditioned to anxiety, the instruction is to touch the door handle every time after he has washed his hands. If the anxiety conditioned stimulus is not at hand (for instance, if the exposure was to the door handle in the therapist’s office), re-exposure involves instructing the patient to choose an object that will be used as a ”re-exposure object” (if the patient has a mobile phone, it is the ideal re-exposure object) and then asking him to touch this object directly after having touched the door handle (the feared stimulus). In this way, the re-exposure object (the phone) takes over the anxiety-evoking function (it is now also “contaminated”) and it can thus be used as a therapeutic object: The patient is instructed to touch his phone after every time he has hand-washed. This technique was initially called the “rag technique”, simply because the re-exposure object (well before mobile phones became common) was usually simply a rag (a piece of cloth).

By using this technique of re-exposure, the OCD-related function of the hand-washing (what makes it a compulsion) is taken away, whereas the other, non-OCD-related function of handwashing (we all wash our hands having been to the bathroom to defecate) is not changed (there is no residual excrement on our hands).

Challenges in ERP

ERP is a challenging, but is also the most clearly effective evidence-based psychological treatment for OCD. More than other anxiety related problems, OCD may include so called “overvalued ideation” (a patient’s poor insight). It also touches on broad existential questions (as “What can we really be sure about in life?”. Moreover, certain obsessions, such as religious (for example “blasphemous thoughts”) and sexual obsessions (such as “forbidden” sexual mental images) touches on themes that are sensitive to most people, also those who do not suffer from OCD. Therefore, some aspects of doing ERP as a therapist may be more challenging than other forms of exposure therapy. Not because the principles of ERP would be different than other forms of exposure therapy (they are exactly the same), but because the themes worked on in therapy are more sensitive and challenging for us all. Fortunately, exposure is just as effective for therapists as it is for patients!

Mental rituals

Some therapists find OCD more demanding because some patients primarily have mental rituals (mental compulsions). Examples of this within the domain of religious OCD may be, as mentioned, saying a prayer several times (as compulsion) after having the obsession that one is “non pure” or that one could be punished by God. Because it’s usually not physically possible to _not_ do a mental ritual (it is impossible not to think, it comes automatically), in a way it is physically possible (although emotionally difficult) not to wash your hands (one can control ones muscles but not ones thoughts), for mental rituals the principle of re-exposure becomes particularly important: The patient that performs his compulsion of saying a prayer one more time is instructed to re-expose himself to the blasphemous thought or image. In this way, he will get the experience, exactly as in all prolonged exposure, that the anxiety will decline over time, and it will be possible to experience something new, even if the discomfort isn’t neutralised by a ritual.