One of the most common misconceptions about cognitive behavioural therapy (CBT) is that it involves challenging negative thoughts and replacing them with more positive or realistic ones. There are certainly situations where examining our thinking can be helpful. However, when it comes to obsessive-compulsive disorder (OCD), challenging intrusive thoughts can sometimes become part of the problem. To understand why, we need to look at what someone is trying to achieve by challenging a thought.
The problem with trying to prove OCD wrong
Imagine someone experiences an intrusive thought that they might hurt somebody they love. Naturally, this could be extremely distressing. They might try to reassure themselves that they’re a good person, remind themselves that they’ve never intentionally hurt anyone, or mentally review their past behaviour looking for evidence that they’re not dangerous. At first glance, these responses might sound perfectly reasonable. But what happens when the doubt returns? Perhaps the person begins questioning whether they really know themselves. What if they secretly wanted to act on the thought? What if they’ve overlooked something? They may then feel compelled to analyse the thought all over again. Although they’re attempting to challenge the original thought, the process has become a form of mental compulsion.
When does challenging a thought become compulsive?
I think the most useful distinction is often the function of the thinking. Are you considering a thought to understand something, develop a different perspective or make a practical decision? Or are you repeatedly analysing it because you feel you need certainty before you can move on? In OCD, thought challenging can become an attempt to eliminate doubt, reduce anxiety or prove that a feared outcome won't happen.
The problem is that trying to achieve certainty can reinforce the belief that certainty is necessary. And because absolute certainty is rarely possible, the analysis can continue indefinitely. Someone might spend hours going backwards and forwards over the same question, occasionally feeling reassured, only for another doubt to appear. In this way, the very strategy they're using to overcome OCD can end up maintaining it.
What should we do instead?
One of the central principles of exposure and response prevention (ERP) is learning to experience intrusive thoughts, feelings and uncertainty without performing compulsions. This doesn't mean agreeing with the thought, believing that it's true or deliberately trying to suppress it. Instead, we're learning that we don't always need to respond to an intrusive experience. For example, someone might notice the thought that they could be a dangerous person and practise allowing the associated uncertainty to remain, without reviewing memories, checking their feelings or reassuring themselves. They can then return their attention to whatever they were doing.
This can feel incredibly uncomfortable initially, particularly when OCD makes the question seem urgent or morally important. But with practice, the person can learn they don't need to resolve every intrusive doubt to get on with life. Importantly, the goal isn't to find a new statement that makes the thought feel less threatening. Even repeating something like "it's just OCD" can become compulsive if we're using it over and over again to obtain reassurance. We're learning to change our response to the thought, rather than trying to find the perfect answer.
Does this mean cognitive techniques are unhelpful?
Not at all. Cognitive approaches can be extremely valuable in OCD treatment, particularly when examining beliefs about responsibility, threat, uncertainty and the significance of thoughts. For example, someone might believe that having a thought about a terrible event makes that event more likely to happen, or that failing to prevent every possible risk would make them personally responsible for the outcome. Exploring these underlying beliefs can be a useful part of therapy. However, there's an important distinction between examining a general belief as part of treatment and repeatedly debating a particular obsession to obtain reassurance. The former can help us develop a different understanding of OCD. The latter can keep us trapped in the very cycle we're trying to overcome.
This is why CBT for OCD needs to be adapted to the particular processes that maintain the disorder, rather than simply applying generic thought-challenging techniques.
So, should intrusive thoughts be challenged?
Sometimes it can be helpful to examine the beliefs that influence how we interpret intrusive thoughts. But repeatedly trying to disprove or neutralise the thoughts themselves can become a mental compulsion. The aim of treatment isn't to develop a perfectly convincing argument against every intrusive thought. It's to change the relationship we have with those thoughts, so they no longer dictate our behaviour. And sometimes, the most helpful response to an intrusive thought is to allow it to remain unanswered.