There have been a number of psychology studies that indicate the usefulness of both short and long breaks.
Nevermind preventing damage to your eyes by not looking at a screen, but a 10-15 minute break will allow you new stimuli (to keep your mind fresh), and a chance to push that problem you've been turning over into your subconscious. It's not by coincidence that 'sleeping on it' often makes whatever hard problem we have to deal with a little clearer and less complex. By distracting our consciousness from the problem it allows our powerful subconsious to take it over (the same subconscious that's capable of comprehending speech's sound waves and turning them into meaningful concepts, as well as many other amazing feats).
In short, I stay focused by not staying focused.
Aside: While caffeine can make you feel more awake, it's much more of a detriment in the long run. You'll get a burst of clarity but then be left largely befuddled by the drug itself... best to stay away from it.
Slashdot Mirror
There have been a number of psychology studies that indicate the usefulness of both short and long breaks. Nevermind preventing damage to your eyes by not looking at a screen, but a 10-15 minute break will allow you new stimuli (to keep your mind fresh), and a chance to push that problem you've been turning over into your subconscious. It's not by coincidence that 'sleeping on it' often makes whatever hard problem we have to deal with a little clearer and less complex. By distracting our consciousness from the problem it allows our powerful subconsious to take it over (the same subconscious that's capable of comprehending speech's sound waves and turning them into meaningful concepts, as well as many other amazing feats). In short, I stay focused by not staying focused. Aside: While caffeine can make you feel more awake, it's much more of a detriment in the long run. You'll get a burst of clarity but then be left largely befuddled by the drug itself... best to stay away from it.