I didn't believe him (a.k.a. the dumbing down of Matt)

One of the first five things Michel told me when I arrived in Japan (he went on to tell me much more than these first five things - all good advice - but they don't come into this topic) was that I would start to slowly lose my vocabulary. He told me that when you spend your day simplifying your classroom English for your students, all those brilliant words not getting used drift back to the far recesses of your mind and are left forgotten like a ketchup packet at the bottom of a kitchen drawer. I didn't believe him at first. I love using words and finding the perfect word to use. I told myself that this would not happen to me. I even laughed on Monday when Alex couldn't remember the word "Zoo" ("It's that place with the animals..."). But I am forced to come to the frightening conclusion that this is happening to me as well, but I think on a grander scale. It's not just single words that are vanishing like socks in the laundry, it's whole phrases and ideas. And it comes at a point where I really want to do more writing. I sit down, open my notebook and uncap my pen and begin. Yet nothing substantial comes out. I have three good story ideas that are all in different stages and none of them is developing into anything substantial. I need to get out of this state of atrophy. Any ideas on how to do this?