The link between thought suppression and anxiety
If you are suffering from an anxiety-related problem, or are just plain worried, you are likely to be plagued by anxiety-provoking, 'intrusive thoughts'. These commonly include things like:
-Everyone can tell how anxious I am (social phobia).
-If I don't keep checking the cooker, the house will set on fire (OCD).
-I just know I will get cancer (health anxiety).
-If I don't worry about the family all the time, who will? (generalised anxiety disorder).
You might also be troubled by intrusive images, which is especially common in post-traumatic stress disorder (PTSD). Images are more emotionally laden and often more powerful than the verbal thoughts, above, so a visual flashback of the traumatic incident you went through can bring all the emotions associated with it flooding back. So it's entirely natural to try and force these intrusive thoughts or images from your mind, perhaps by distracting yourself or, in the case of OCD, 'neutralising' them by carrying out a compulsive behaviour like checking or washing.
Unfortunately, although thought suppression is both natural and completely understandable, it actually makes the problem worse. That's because when we try to suppress a thought, rather than getting rid of it, we make it stronger - a process known as 'thought rebounding'. Try this simple experiment to see how this works for yourself:
-For the next minute, I want you to think of anything at all, but do not think about green polar bears. Whatever you do, don't think about green polar bears... keep thinking, about ANYTHING but green polar bears.
So, what happened? My strong hunch is that a certain large furry animal kept popping into your mind. So ask yourself this - have you ever thought about green polar bears before? I'm guessing not. So, ironically, it was only because you were trying so hard NOT to think about one that you did. A perfect example of how thought suppression leads to thought rebounding.
Instead of trying to suppress those upsetting thoughts, you need to learn how to either process the traumatic experience you are trying to forget (especially with PTSD), learn how to modify unhelpful beliefs or behaviours, or use mindfulness techniques to change your relationship to the thoughts themselves, so you can simply notice them and then let them go.