ADHD is the big word.

ADD is just the inattentive type.

ADHD (combined can be any of three attention, impulsivity or hyperactivity) (DSM)

Dr. Daniel Amen has done some brain imaging on ADHD. Many docs and therapists think he is a quack. I am just glad that some docs are taking an interest in ADD and ADHD.

He has broken ADHD into 7 subtypes. His link is below.

Attention Deficit Disorder ADD/ADHD - Amen Clinics