When I don't sleep enough, which has been a staple of my adolescence, everything is just slower. My brain feels foggy, and my memory is out of whack. If I ever try and cram for an exam the next day and get little sleep because of it, I'll forget most of the stuff I reviewed the night before. My vision even feels like it's worse, and my blinks will feel like slow motion. I even find it harder to perform athletically, like my muscles are tired and even my lungs are saying they need sleep.