Ineffable Ontological Detanglement .: Introspective Assistance & Mental Analysis Manual
Thought looping is when you can't get rid of a repeating thought it's just happening over and over and over and over and taking over, sometimes entirely, your train of thought. You're losing control, you can't terminate. Something is very threatening, you've semi-consciously decided to engage in this and you're going to have to figure out how to semi-consciously get out of it, you're going to have to click your conscious mind in just the right manner that will convince you all the way semi-consciously that you need to stop, sometimes all you can do is give it time and let it fizzle as conscious panic isn't going to help you any. Attentional gating pretty much only wants the thought loop, you can bring other things into your attention however only about 50% and quickly dwindling, you have to really struggle to maintain that 50%.
Obviously anxiety puts you in a lot of trouble, you're going to have a hard time getting out of it, you're more likely to fall into it. Panic disorder leaves you helpless before it, the likelihood of you getting out of it is quite remote you'll probably need to figure out how to sleep it off. The less cognitive flexibility and lability you have the less chance you have of getting out of it.
Error correction has constructed a model, made it's predictions, found a solution. At this point the process is supposed to terminate, however the solution in no way matches the predictions, this is going to fail. There's no solution. Maybe the solution is too frightening, it opposes your identity, your morality. It could be a what if that brings you here, a why do I do this why am I like this, if this is true then that means. It could be based in a cognitive dissonance over something incredibly significant to your perception of self or reality.