I found this article after my 13-year-old had a harder time memorizing lines in his month long musical theater camp this summer when he had always in the past been able to memorize his lines faster than most of the other kids. He was only getting five or six hours of sleep at night because he had a really hard time sleeping in the painful brace he has to wear and although melatonin would make him a little sleepy it wasn't enough to help him relax enough to fall asleep when he hurt.

http://nymag.com/news/features/38951/index2.html

He did manage to memorize all of his lines but he very definitely had more trouble concentrating when he was so tired, and I think it probably looked a little like ADD.

When the play was over he went back to sleeping later in the mornings and his temporary "ADD" disappeared.

He has always been able to get away with one or two nights without sleep. It is when he gets less than six hours of sleep for more than three nights that he starts having trouble.

I have an even harder time with lack of sleep than my son does and when he doesn't sleep I don't sleep well. I get very grouchy and depressed when I don't get enough sleep and it makes my anxiety worse.