I have become kind of curious about ADHD recently, and my general understanding is that people with ADHD have problems focusing on specific things, and feel overwhelmed by a lot of information and also are often very restless.
Then I also realised that the popular show South Park actually has a character (Tweek) with a confirmed ADHD diagnosis, and this is what I have noticed in that character:
*eye tics that make him blink randomly
*very jumpy, and gets scared easily
*easily gets frustrated
*trouble sleeping
*uses relaxation techniques to help him with stress
Here are a few videos with him that show some examples of how he acts - what do you think?
Of course, I should probably also point out that his parents give him lots of coffee very often since they think that it helps him relax, but they give him so much of it that it seems to make him even more jumpy instead.
I would say that it's probably not entirely accurate, but it doesn't seem totally inaccurate either;
some factors definitely seem reasonably believable.