Yes, for sure. If I spend too much time on the computer my mind races with what I was just researching. (I like researching things that I become interested in, whatever my mini-interest at the time is). Sometimes I'll just be thinking about all of the stuff I saw/read, sometimes I'll be depressed or scared if the content was depressing or sometimes if I was on a social networking site I'll be thinking about friends and possibly my past relationship which will end up making me depressed.
Also, whenever you look at a bright screen, so basically your computer or your cell phone it does something to your brain that kind of distracts you I guess and causes you to be less tired. I don't know what it's called and I don't know how to explain it, I just know that it's a fact. I used to randomly check my cell phone in the middle of the night and my boyfriend at the time would get mad and explain what I basically just told you. It's true if you think about it though. I guess the light and the distraction stimulates your mind which causes you to be more alert.