I'm glad to know that a central issue has been covered. Just was worried thinking about it.

Here's an article that may be of interest:
http://brainposts.blogspot.com/2011/11/neuropsychology-and-cerebellum-part-ii.html#!/2011/11/neuropsychology-and-cerebellum-part-ii.html

One quote from there:
"Greater decrease in cerebellar volumes are seen in children with ADHD not treated with stimulants suggesting stimulant medication may reduce cerebellar abnormalities in ADHD"