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Your heart pounds, your stomach's in knots, and you're sweating even though the kitchen is cool. Someone might die, and it's your fault. While trying to clear your dining room table you set down a plate while thinking the word "crash," and now someone in your family could die in a plane crash. You've been trying to clear the table for an hour now, but every time your mind pairs an action with a "bad" thought, you have to redo the action. So much for having time to unwind before bed—another night, ruined by OCD.
How would exposure and response prevention, or ERP, treat this form of OCD? As I wrote in an earlier post, the treatment is about doing the opposite of what OCD says to do. All we have to do, then, is figure out what OCD is saying:
1. Don't think bad thoughts when you do things.
2. Don't think about what might happen if you have a bad thought while doing something.
3. If you think a bad thought when you do something, do it again while having a good thought. PS: If you fail, repeat until you get it right.
So now we know what you have to do:
1. Deliberately think bad thoughts when you do things (the exposure of ERP).
2. Deliberately think about the bad things that might happen because you had the bad thoughts (more exposure).
3. Don't repeat actions that are paired with bad thoughts (the ritual prevention).
As this example shows, therapists actually have two kinds of exposure at their disposal. The kind we probably think of first is real life or "in vivo" exposure, which just means doing the thing OCD doesn't want you to do. In this example that would mean doing lots of actions while intentionally thinking bad thoughts.
Part of what's super helpful about in vivo exposure is that it can show that the scary thing doesn't really happen—what psychologists call "disconfirmation of the feared consequence." In vivo can also teach you that your anxiety doesn't last forever even if you do the scary thing and don't do a compulsion.
The second kind of exposure is called "imaginal." As the name suggests, it involves imagining something rather than doing something. What you'll imagine is the thing you're afraid of happening because you didn't do a compulsion. The therapist will help you create a story about something awful that happens because you had a bad thought while putting something down and didn't neutralize the bad thought with a good one. You'll then make a recording of the story and will listen to it over and over. With enough repetition the story wil stop being frightening.
Imaginal exposure seems to help because it teaches you that thinking about bad things doesn't actually make them happen. Also, as the feared disaster become less scary, it causes fewer obsessions—if I'm not as afraid of the disaster, I'm less worried about things that could cause it. It can also be powerful to learn that thinking about one's worst fears doesn't make a person "go crazy" or "fall apart." On the contrary, nothing shrinks our fears like facing them.
So where do therapist mistakes come in? Sometimes therapists will ask the person with OCD to do an imaginal exposure when what's really needed is a real-life (in vivo) exposure. For example, the therapist might instruct a person with germ-related OCD to imagine touching a toilet. While it's probably unpleasant for the person to imagine touching the toilet, it's not nearly as effective as having the person actually touch a toilet.
If it's only done in imagination, the OCD can always say, "But you didn't actually do anything, so nothing bad can happen," which of course is true.
Choosing the right form of exposure is crucial for maximizing treatment success in ERP for OCD.
In a future post I'll address the related issue of failing to use imaginal exposure, which prevents getting at the core fear that drives the obsessions.
