Answer from Master Keisen
Open your eyes wide open and look at something (like the wall). That will send you back in the world of reality instead of your inner world of recurrent thoughts.
You may notice also that when you go in your thoughts your head will a bit fall forwards. Immediately observe it and straight up your neck with energy.
Breathe in strongly in one go, that will refresh your brain.
But ultimately it is difficult to stop the thoughts when they have appeared. So you should be attentive and cut them at the root before they develop. Do that, and then you will get used to it and it will be easier.
Mondo On the same theme : Thoughts
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