All this is starting to get interesting. I'm especially interested by what Gardener and cwoodgold said - I'd never really thought about it properly though I'd be lying if I said it wasn't on my radar.
Let me explain. I have a 4 year old boy - he is the light of my life and has been diagnosed with autism. Now he has a moderate case - the largest concern was that he - at 4 and a half years old - is now only really beginning to talk in earnest - and even now we're only at one and two word phrases intermingled with sign language.
Now I talked early and being born in a small village in the 70's I don't think anyone there knew what autism was. But as the pediatrician was talking us through her concerns for my son I sat there silently going "I do that.", "That sounds like me", etc. Not as severe - but the tendencies are there.
I need to do more research but my over-simplistic view is that ADHD, ADD and autism are all in the same realm - they are most certainly not the same but for example with my little boy I know he is really really bright. BUT - and it's a big but - he's really bright only when you can get his attention and hold it. If you can motivate him (reward?) then he can learn things that I think he's struggled with for ages in a matter of minutes only having been shown once. It's not that he's deficient in his mental capacity - rather getting enough of his "brain time" for it to process what you need him to learn is the challenge.
And so it is with me - if I go back to my school days - I could never handle subjects like history - to sit through and hour of listening to facts was impossible for me. I'd be lucky if I made it 5 minutes in before my brain switched off. I was constantly doodling to keep my brain going and to stave off the feeling of going out of my mind with boredom. However maths - that I could do - pay attention for 5 minutes and learn the formula and then apply it ad infinitum - easy peasy. I excelled in maths, science, computer studies. At university I trained to be an electronic engineer (applied maths).
Now here I am in my mid thirties and in some ways I have grown hugely. In other ways little has changed.
I am known at work for my lack of attention span. For me meetings are a death sentence unless I am actually involved in a lively debate or the centre of attention. But I work in IT. And it would be easy to sound conceited but I'm good at it. Very good. To the point where I'm viewed of as more or less indispensible (as was proved the other day when I talked to my superiors about leaving the company).
But my level of skill is all based around my ability to work round my "condition" - I can store enough information in my head to attack most things - but I can't remember all the specifics. For that I use Evernote - it's like my brain stores the clues or crumbs and then I rely on something to store the detail.
I am guilty of procrastination. And I do feel good when I let up a bit and give myself some play time.
I do seem to work well under pressure and when the adrenalin is flowing - however as is the case with adrenalin sooner or later it burns out and then I'm left feeling listless, directionless, and back into procrastination mode.
I feel like I'm really onto something here - haven't had time to do any reading yet but the next question in my mind if naturally "ok - if this is me then what do I do next?".