you're right, our ability to write code depends on "right and left brain activity" / creative energy. I learned a lot from TCM (Traditional Chinese Medicine) regarding the cause of such "blockage". It depends most time on a problem with the "liver energy". Our sedentary way of life is problem number one. This cause in us a blockage of liver energy and the creative energy depends on that on a long term.
One solution: move!
Sport or taking a walk helps a lot.
Another possible cause: We may think, without being conscious of it, that the entire project makes no sense. If this is true or not, our subconscious part will not release creative energy in an abundant manner.
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