If he is a hyperactive subtype, by far the research has extensively proved stimulants to be much more effective.

I don't have time to scan through all this but check into links on this on the ADDitude.mag site. It is completely linked to ADHD and the fact that her brain is different. I am an adult with ADHD and remember doing this as a child almost like an involuntary response. Remember kids with ADHD have about 10 negative interactions for every positive one, especially if they are unmediated and don't have much control over impulses or even know what it feels like. They may even be still reeling from the thing you are asking them about trying to figure out if THEY even know why they did it.