I don't have cataplexy, but I have a very frustrating form of (undiagnosed) narcolepsy where I get REM episodes through the day while I'm awake. They make it very hard to concentrate or get any work done. If I close my eyes they are REM-ing (if that's a word), and if I'm in a place where I can lie down I will enter a semi-dream state and fall asleep pretty quickly. They consistently last about 20 minutes, just like the night-time REM episodes normal people have when they sleep.
I really wish I could get rid of them. (I'm in the middle of one right now.)
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