I did use it for a while, because I had issues starting to work. It helped with that but like you said, 25m were not enough and the interruptions got quite annoying. I tried a 45m/10m work/pause ratio instead and it was a bit better, but I don't really use pomodoro anymore.
It helped me to form a "habit of starting" though.
I don't think that fear and anxiety are exactly the same thing. (fear being a very basic response to a very concrete (perceived) threat, while anxiety is more diffuse, constant, covering larger timeframes)
Assuming we are talking about the same thing (anxiety), why do you think that not everyone suffering from OCD has that as the cause? What other types do you know of?
It is possible that I was focusing too much on intrusive thoughts and related issue, but my current understanding is that the OCD mechanism described above is the same for any type of OCD and that it is by definition an anxiety disorder.
The discomfort you are describing could be the same thing as the anxiety I was speaking of, although discomfort is maybe not intense enough to describe the internal experience of the disorder.
As always: these things are distributed on a spectrum with better/worse days and cases between people. It only becomes a disorder if you suffer from it on a regular basis in some phase of your life.
Obsessive compulsive disorder is a form of anxiety disorder. You are afraid of something (sickness, death, loosing control) - then you get obsessive about it and then you do some compulsive action to mentally ease that thought/anxiety.
But now you have "learned" to behave in a certain way to feel better. And you are weighting the triggering thought as more important by giving that much attention to it. This is resulting in a self-enforcing feedback loop in the end.
Behavioral therapy is a way to "unlearn" this behavior. Mostly by working against the initial anxiety. If you are unconcerned/neutral/bored of something, you cannot gain that much obsessive/compulsive momentum.
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