The body has a clock governing the time of day certain activities should be done. It’s inevitable at some point in the modern world, you will want to compute late at night without messing up the body’s schedule. Below are some tricks I’ve discovered to keep my sleep/wake schedule somewhat intact over the years.
The human body clock has a number of input techniques to determine what time it is. One of these ways is the detection of light via photoreceptors in your eyes. The light passes through your eye (or eyelid if it’s closed) and triggers some very complicated chemical reactions in your brain. This is one of many time sensing algorithms the body uses, but it is probably the easiest to manipulate.
When I am computing late at night for a short period of time, I will set the computer to “reverse video” or set the background to a solid black color. This simple tweak causes the monitor to cast fewer lumens on my eyes. Since my eyes are detecting lower light levels, my body won’t work against the clock cycle and I will be able to fall asleep in a few hours. If I have my computer set to high light levels, or leave the lights on, I have found it is much easier to stay awake.
To set an Apple Mac to Reverse Video display in OS X Leopard, click on the Apple in the upper lefthand corner, then System Preferences, then Universal Access. Then click “White on Black” under Display. This essentially makes everything look like a film negative, which is a little fun. I would not watch a movie or do photo editing with the display set to this mode however for obvious color based reasons. It might be fun for a little while but I think it would get old fast. Usually I set the background to a solid dark color for color sensitive applications. You can also turn the brightness and contrast down on the monitor and turn all the room lights off.
I read about another technique regarding body clock shifting. The theory is that the entire clock can be shifted forward or backwards by regulating light using sunglasses. Late risers looking to wake up earlier wear sunglasses in the afternoon and evening. People who are early risers looking to wake up later can wear sunglasses in the early morning.
Whatever you can do to throw less light at your eye late at night, the better your clock will stay in sync with natural sunlight. This can be used to great benefit if your a late sleeper and you need to clock shift. I’m not sure how much sway the clock is susceptible to with regard to free will, but it might be fun to try.
Sleep well!