In research not yet published, Barkley has found new elements associated with attention deficit. We're beginning to think of ADHD as more of a problem with self-control, not just with inhibiting. People with attention deficit lack good working memory, the ability to hold in your head bits and pieces of information needed to get through the day. Working memory is also where you get time control. Lack of time control is devastating.
Western culture worships time.
By age 8 or so, we've learned not to speak those instructions aloud, but that little internalized voice still helps control our actions. Children with attention deficit quiet that voice 30 percent later than normal and don't appear to ever fully internalize it. Although most people don't think of it this way, part of self-control is being able to readjust your plans when you hit an obstacle. In problem-solving, and in many academic pursuits, attention deficits drags down a person's potential. Someone who has normal to high potential intelligence is more likely to find ways to compensate for the deficit.