I like what writer-director Rodrigo Garcia has to say about uninspiration or writer's block.
Writer's block is very many different things...Sometimes you're just writing too soon- meaning you are too tired from the last thing you were doing. [Or] you haven't replenished enough: you haven't seen enough films, heard enough music, gotten out into the world, gotten out of town...You have to energize. And ultimately the final thing is you sit down and you write no matter what. Sometimes I will dictate a scene into a recorder. Writer's block is not a virus; it's you. If you don't get yourself out of it, then that's it--that's where you're going to live.
Garcia said this during an interesting Creative Screenwriting Magazine podcast where he, producer Julie Lynn and Samuel L. Jackson discuss working on Mother and Child.