Often someone who is bone-tired will lay down in bed and flip on the TV or his laptop thinking that it would be nice to relax for a few minutes before going to sleep.
And often, he'll end up catching a second wind and stay awake another hour or two watching some old movie or reading some web-site.
Whence blows this second wind?
Light emitted from televisions and computers that shines directly into the eyes suppresses the sleep inducing hormone melatonin.
- The End of Illness (2011) by David B. Agus, page 254