Have you ever been in a shop and suddenly had the unexpected urge to knock all the items off the shelves? What about imagining yourself randomly insulting a stranger, or shouting something rude in public?

What are intrusive thoughts?

We experience thousands of thoughts per day, and often we are not even consciously aware of their content. Intrusive thoughts however are those thoughts and images that unexpectedly pop into our minds and are distressing enough for us to take notice of them.

Although particularly common in anxiety disorders, OCD and PTSD, most people will experience them at some time, even without any other symptoms of poor mental health. In fact, studies have shown that up to 94% of the population have these thoughts at some point.

When do they become a problem?

Intrusive thoughts are harmless; however, they can feel distressing if we attribute meaning or significance to them, particularly if their content is at odds with our personal beliefs or values. A religious person who has blasphemous thoughts and then believes this makes them a 'bad person' will have a tendency to experience more guilt and shame than a non-religious person, or a religious person who understands that these thoughts are meaningless and hold no value. They can therefore become problematic if we believe the thoughts say something about us as a person, we become overly focused on them, and change our behaviour as a result.

An example of this may be a new mother who suddenly has an intrusive thought of harming her child. This can trigger a perception of herself as a bad mother, fear that having the thought may mean she will act on it even though she can think of nothing worse , and subsequent avoidance perhaps refusing to spend time alone with her baby, or not picking her up in case she drops her .

Unfortunately, most of the time we keep these thoughts to ourselves. Many people fear that they will be judged, perceived as 'odd', or even dangerous. Lack of communication then perpetuates the belief that intrusive thoughts are uncommon, and that other people will not understand. There is often the concern that 'thinking it' must mean that deep down we must either want to do it, or that we are at risk of doing it, triggering feelings of confusion, anxiety, or shame, and the unspoken cycle continues.  This is particularly true if the thoughts are of a sexual or violent nature.

Some of the more common intrusive thoughts experienced within 'non-clinical subjects':

• Did I leave an electrical appliance on, that could cause a fire?
• Did I leave the door unlocked?
• Imagining people naked when talking to them
• Having the urge to say something rude, or insulting, to a friend, or a stranger