I also found writing useful to stop my head from circling around problems repetitively. Writing serves me not only to think, but to actually see the structure of that thinking process (a beginning and an end, argumentation), hence seeing the whole picture and how I am are not deliberately missing something.

This eventually frees me to focus in other things, feeling that I did as much as I could with the thinking at that moment. New ideas may come eventually, but for the moment that thinking "batch" is ok.