I've always been a late-onset insomniac, and my Mum has exactly the same problem. My body clock simply will not synchronise with the outside world - or rather, it does synchronise, but with a delay of several hours. I've tried medications, light-boxes, sleep-hygiene, diet, eliminating caffeine, napping etc., but nothing has ever been reliable or worked for any length of time.
At times when I'm able to live with the time offset, I settle into a perfectly stable sleep pattern, feel much more rested after sleeping, have more energy generally, and remember far more dreaming. When I try to synchronise with the outside world, even extreme amounts of sleep-deprivation will often not get me to sleep any easier nor make sleep any more restful on the night that follows (I was like this right through school and have had periods of working full-time.)
I was just describing in another thread how this has lead to me being mistaken for a drunk or a drug user due to how sluggish my brain gets as the work/school week drags on. I dread to think how hard it must have been for my Mum when I was little; getting me ready for school before work for years with both of us always "zombied" from multiple nights of only a few hours sleep. Having a Mum who understood the problem sure helped, though!
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