Insomnia and Zeitgebers

After trying to fall asleep for over half an hour with no success, my restless brain which has refused to shut down, has now ordered me to get up.  I often have trouble falling asleep.  Or if I do fall asleep I will awaken a few hours later and have trouble getting back to sleep.  Maybe my circadian rhythms are those of a night owl or maybe I march to a different Zeitgeber.  I had never heard of a Zeitgeber before reading about circadian rhythms on Wikipedia.  But there is such a thing as a Zeitgeber.  It is the time cue that synchronizes your biological, internal time clock to the earth's 24 hour light/dark cycle.  In other words, it's what helps you fall asleep when it gets dark and awaken when the sun comes up.  I'm not the only one in my family that has night owl tendencies.  I remember my father would often be up late, either working in his lab at the University or at home watching late night TV.  Then he would sleep late in the mornings, not getting up until after I had left for school.  But my brother is the one who seems to have the strongest affinity for night-time wakefulness.  From what he has told me, and from what I recall when he would stay with us while visiting our mom, he often stays up until 3 a.m. or later and sometimes doesn't get up until past noon.  Even on nights when I can't get to sleep for several hours or waken during the night and lay awake for hours, I always tend to wake up around 7:00 or 8:00, which means that many nights I only get around 5 or 6 hours of sleep, that's if I'm lucky.  On a bad night I might only get 4 hours.   When I'm not feeling sleepy and when I know after trying for awhile that I'm not going to fall asleep anytime soon, I will get up and either watch television or work on my computer.  So here it is, 1 a.m. and I think I'll work for a bit on my latest illustration.  More about it later . . . maybe in the morning?